fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/jbd2.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/parser.h>
  29 #include <linux/smp_lock.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/proc_fs.h>
  39 #include <linux/ctype.h>
  40 #include <linux/log2.h>
  41 #include <linux/crc16.h>
  42 #include <asm/uaccess.h>
  43
  44 #include "ext4.h"
  45 #include "ext4_jbd2.h"
  46 #include "xattr.h"
  47 #include "acl.h"
  48 #include "mballoc.h"
  49
  50 #define CREATE_TRACE_POINTS
  51 #include <trace/events/ext4.h>
  52
  53 struct proc_dir_entry *ext4_proc_root;
  54 static struct kset *ext4_kset;
  55
  56 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  57                              unsigned long journal_devnum);
  58 static int ext4_commit_super(struct super_block *sb, int sync);
  59 static void ext4_mark_recovery_complete(struct super_block *sb,
  60                                         struct ext4_super_block *es);
  61 static void ext4_clear_journal_err(struct super_block *sb,
  62                                    struct ext4_super_block *es);
  63 static int ext4_sync_fs(struct super_block *sb, int wait);
  64 static const char *ext4_decode_error(struct super_block *sb, int errno,
  65                                      char nbuf[16]);
  66 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  67 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  68 static int ext4_unfreeze(struct super_block *sb);
  69 static void ext4_write_super(struct super_block *sb);
  70 static int ext4_freeze(struct super_block *sb);
  71
  72
  73 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
  74                                struct ext4_group_desc *bg)
  75 {
  76         return le32_to_cpu(bg->bg_block_bitmap_lo) |
  77                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  78                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
  79 }
  80
  81 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
  82                                struct ext4_group_desc *bg)
  83 {
  84         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
  85                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  86                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
  87 }
  88
  89 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
  90                               struct ext4_group_desc *bg)
  91 {
  92         return le32_to_cpu(bg->bg_inode_table_lo) |
  93                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  94                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
  95 }
  96
  97 __u32 ext4_free_blks_count(struct super_block *sb,
  98                               struct ext4_group_desc *bg)
  99 {
 100         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 101                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 102                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 103 }
 104
 105 __u32 ext4_free_inodes_count(struct super_block *sb,
 106                               struct ext4_group_desc *bg)
 107 {
 108         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 109                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 110                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 111 }
 112
 113 __u32 ext4_used_dirs_count(struct super_block *sb,
 114                               struct ext4_group_desc *bg)
 115 {
 116         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 117                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 118                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 119 }
 120
 121 __u32 ext4_itable_unused_count(struct super_block *sb,
 122                               struct ext4_group_desc *bg)
 123 {
 124         return le16_to_cpu(bg->bg_itable_unused_lo) |
 125                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 126                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 127 }
 128
 129 void ext4_block_bitmap_set(struct super_block *sb,
 130                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 131 {
 132         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 133         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 134                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 135 }
 136
 137 void ext4_inode_bitmap_set(struct super_block *sb,
 138                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 139 {
 140         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 141         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 142                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 143 }
 144
 145 void ext4_inode_table_set(struct super_block *sb,
 146                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 147 {
 148         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 149         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 150                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 151 }
 152
 153 void ext4_free_blks_set(struct super_block *sb,
 154                           struct ext4_group_desc *bg, __u32 count)
 155 {
 156         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 157         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 158                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 159 }
 160
 161 void ext4_free_inodes_set(struct super_block *sb,
 162                           struct ext4_group_desc *bg, __u32 count)
 163 {
 164         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 165         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 166                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 167 }
 168
 169 void ext4_used_dirs_set(struct super_block *sb,
 170                           struct ext4_group_desc *bg, __u32 count)
 171 {
 172         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 173         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 174                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 175 }
 176
 177 void ext4_itable_unused_set(struct super_block *sb,
 178                           struct ext4_group_desc *bg, __u32 count)
 179 {
 180         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 181         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 182                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 183 }
 184
 185
 186 /* Just increment the non-pointer handle value */
 187 static handle_t *ext4_get_nojournal(void)
 188 {
 189         handle_t *handle = current->journal_info;
 190         unsigned long ref_cnt = (unsigned long)handle;
 191
 192         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
 193
 194         ref_cnt++;
 195         handle = (handle_t *)ref_cnt;
 196
 197         current->journal_info = handle;
 198         return handle;
 199 }
 200
 201
 202 /* Decrement the non-pointer handle value */
 203 static void ext4_put_nojournal(handle_t *handle)
 204 {
 205         unsigned long ref_cnt = (unsigned long)handle;
 206
 207         BUG_ON(ref_cnt == 0);
 208
 209         ref_cnt--;
 210         handle = (handle_t *)ref_cnt;
 211
 212         current->journal_info = handle;
 213 }
 214
 215 /*
 216  * Wrappers for jbd2_journal_start/end.
 217  *
 218  * The only special thing we need to do here is to make sure that all
 219  * journal_end calls result in the superblock being marked dirty, so
 220  * that sync() will call the filesystem's write_super callback if
 221  * appropriate.
 222  */
 223 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 224 {
 225         journal_t *journal;
 226
 227         if (sb->s_flags & MS_RDONLY)
 228                 return ERR_PTR(-EROFS);
 229
 230         /* Special case here: if the journal has aborted behind our
 231          * backs (eg. EIO in the commit thread), then we still need to
 232          * take the FS itself readonly cleanly. */
 233         journal = EXT4_SB(sb)->s_journal;
 234         if (journal) {
 235                 if (is_journal_aborted(journal)) {
 236                         ext4_abort(sb, __func__, "Detected aborted journal");
 237                         return ERR_PTR(-EROFS);
 238                 }
 239                 return jbd2_journal_start(journal, nblocks);
 240         }
 241         return ext4_get_nojournal();
 242 }
 243
 244 /*
 245  * The only special thing we need to do here is to make sure that all
 246  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 247  * that sync() will call the filesystem's write_super callback if
 248  * appropriate.
 249  */
 250 int __ext4_journal_stop(const char *where, handle_t *handle)
 251 {
 252         struct super_block *sb;
 253         int err;
 254         int rc;
 255
 256         if (!ext4_handle_valid(handle)) {
 257                 ext4_put_nojournal(handle);
 258                 return 0;
 259         }
 260         sb = handle->h_transaction->t_journal->j_private;
 261         err = handle->h_err;
 262         rc = jbd2_journal_stop(handle);
 263
 264         if (!err)
 265                 err = rc;
 266         if (err)
 267                 __ext4_std_error(sb, where, err);
 268         return err;
 269 }
 270
 271 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 272                 struct buffer_head *bh, handle_t *handle, int err)
 273 {
 274         char nbuf[16];
 275         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 276
 277         BUG_ON(!ext4_handle_valid(handle));
 278
 279         if (bh)
 280                 BUFFER_TRACE(bh, "abort");
 281
 282         if (!handle->h_err)
 283                 handle->h_err = err;
 284
 285         if (is_handle_aborted(handle))
 286                 return;
 287
 288         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
 289                caller, errstr, err_fn);
 290
 291         jbd2_journal_abort_handle(handle);
 292 }
 293
 294 /* Deal with the reporting of failure conditions on a filesystem such as
 295  * inconsistencies detected or read IO failures.
 296  *
 297  * On ext2, we can store the error state of the filesystem in the
 298  * superblock.  That is not possible on ext4, because we may have other
 299  * write ordering constraints on the superblock which prevent us from
 300  * writing it out straight away; and given that the journal is about to
 301  * be aborted, we can't rely on the current, or future, transactions to
 302  * write out the superblock safely.
 303  *
 304  * We'll just use the jbd2_journal_abort() error code to record an error in
 305  * the journal instead.  On recovery, the journal will compain about
 306  * that error until we've noted it down and cleared it.
 307  */
 308
 309 static void ext4_handle_error(struct super_block *sb)
 310 {
 311         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 312
 313         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 314         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 315
 316         if (sb->s_flags & MS_RDONLY)
 317                 return;
 318
 319         if (!test_opt(sb, ERRORS_CONT)) {
 320                 journal_t *journal = EXT4_SB(sb)->s_journal;
 321
 322                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 323                 if (journal)
 324                         jbd2_journal_abort(journal, -EIO);
 325         }
 326         if (test_opt(sb, ERRORS_RO)) {
 327                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 328                 sb->s_flags |= MS_RDONLY;
 329         }
 330         ext4_commit_super(sb, 1);
 331         if (test_opt(sb, ERRORS_PANIC))
 332                 panic("EXT4-fs (device %s): panic forced after error\n",
 333                         sb->s_id);
 334 }
 335
 336 void ext4_error(struct super_block *sb, const char *function,
 337                 const char *fmt, ...)
 338 {
 339         va_list args;
 340
 341         va_start(args, fmt);
 342         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 343         vprintk(fmt, args);
 344         printk("\n");
 345         va_end(args);
 346
 347         ext4_handle_error(sb);
 348 }
 349
 350 static const char *ext4_decode_error(struct super_block *sb, int errno,
 351                                      char nbuf[16])
 352 {
 353         char *errstr = NULL;
 354
 355         switch (errno) {
 356         case -EIO:
 357                 errstr = "IO failure";
 358                 break;
 359         case -ENOMEM:
 360                 errstr = "Out of memory";
 361                 break;
 362         case -EROFS:
 363                 if (!sb || (EXT4_SB(sb)->s_journal &&
 364                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 365                         errstr = "Journal has aborted";
 366                 else
 367                         errstr = "Readonly filesystem";
 368                 break;
 369         default:
 370                 /* If the caller passed in an extra buffer for unknown
 371                  * errors, textualise them now.  Else we just return
 372                  * NULL. */
 373                 if (nbuf) {
 374                         /* Check for truncated error codes... */
 375                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 376                                 errstr = nbuf;
 377                 }
 378                 break;
 379         }
 380
 381         return errstr;
 382 }
 383
 384 /* __ext4_std_error decodes expected errors from journaling functions
 385  * automatically and invokes the appropriate error response.  */
 386
 387 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
 388 {
 389         char nbuf[16];
 390         const char *errstr;
 391
 392         /* Special case: if the error is EROFS, and we're not already
 393          * inside a transaction, then there's really no point in logging
 394          * an error. */
 395         if (errno == -EROFS && journal_current_handle() == NULL &&
 396             (sb->s_flags & MS_RDONLY))
 397                 return;
 398
 399         errstr = ext4_decode_error(sb, errno, nbuf);
 400         printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
 401                sb->s_id, function, errstr);
 402
 403         ext4_handle_error(sb);
 404 }
 405
 406 /*
 407  * ext4_abort is a much stronger failure handler than ext4_error.  The
 408  * abort function may be used to deal with unrecoverable failures such
 409  * as journal IO errors or ENOMEM at a critical moment in log management.
 410  *
 411  * We unconditionally force the filesystem into an ABORT|READONLY state,
 412  * unless the error response on the fs has been set to panic in which
 413  * case we take the easy way out and panic immediately.
 414  */
 415
 416 void ext4_abort(struct super_block *sb, const char *function,
 417                 const char *fmt, ...)
 418 {
 419         va_list args;
 420
 421         va_start(args, fmt);
 422         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 423         vprintk(fmt, args);
 424         printk("\n");
 425         va_end(args);
 426
 427         if (test_opt(sb, ERRORS_PANIC))
 428                 panic("EXT4-fs panic from previous error\n");
 429
 430         if (sb->s_flags & MS_RDONLY)
 431                 return;
 432
 433         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 434         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 435         sb->s_flags |= MS_RDONLY;
 436         EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 437         if (EXT4_SB(sb)->s_journal)
 438                 jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 439 }
 440
 441 void ext4_msg (struct super_block * sb, const char *prefix,
 442                    const char *fmt, ...)
 443 {
 444         va_list args;
 445
 446         va_start(args, fmt);
 447         printk("%sEXT4-fs (%s): ", prefix, sb->s_id);
 448         vprintk(fmt, args);
 449         printk("\n");
 450         va_end(args);
 451 }
 452
 453 void ext4_warning(struct super_block *sb, const char *function,
 454                   const char *fmt, ...)
 455 {
 456         va_list args;
 457
 458         va_start(args, fmt);
 459         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
 460                sb->s_id, function);
 461         vprintk(fmt, args);
 462         printk("\n");
 463         va_end(args);
 464 }
 465
 466 void ext4_grp_locked_error(struct super_block *sb, ext4_group_t grp,
 467                            const char *function, const char *fmt, ...)
 468 __releases(bitlock)
 469 __acquires(bitlock)
 470 {
 471         va_list args;
 472         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 473
 474         va_start(args, fmt);
 475         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 476         vprintk(fmt, args);
 477         printk("\n");
 478         va_end(args);
 479
 480         if (test_opt(sb, ERRORS_CONT)) {
 481                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 482                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 483                 ext4_commit_super(sb, 0);
 484                 return;
 485         }
 486         ext4_unlock_group(sb, grp);
 487         ext4_handle_error(sb);
 488         /*
 489          * We only get here in the ERRORS_RO case; relocking the group
 490          * may be dangerous, but nothing bad will happen since the
 491          * filesystem will have already been marked read/only and the
 492          * journal has been aborted.  We return 1 as a hint to callers
 493          * who might what to use the return value from
 494          * ext4_grp_locked_error() to distinguish beween the
 495          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 496          * aggressively from the ext4 function in question, with a
 497          * more appropriate error code.
 498          */
 499         ext4_lock_group(sb, grp);
 500         return;
 501 }
 502
 503 void ext4_update_dynamic_rev(struct super_block *sb)
 504 {
 505         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 506
 507         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 508                 return;
 509
 510         ext4_warning(sb, __func__,
 511                      "updating to rev %d because of new feature flag, "
 512                      "running e2fsck is recommended",
 513                      EXT4_DYNAMIC_REV);
 514
 515         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 516         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 517         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 518         /* leave es->s_feature_*compat flags alone */
 519         /* es->s_uuid will be set by e2fsck if empty */
 520
 521         /*
 522          * The rest of the superblock fields should be zero, and if not it
 523          * means they are likely already in use, so leave them alone.  We
 524          * can leave it up to e2fsck to clean up any inconsistencies there.
 525          */
 526 }
 527
 528 /*
 529  * Open the external journal device
 530  */
 531 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 532 {
 533         struct block_device *bdev;
 534         char b[BDEVNAME_SIZE];
 535
 536         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 537         if (IS_ERR(bdev))
 538                 goto fail;
 539         return bdev;
 540
 541 fail:
 542         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 543                         __bdevname(dev, b), PTR_ERR(bdev));
 544         return NULL;
 545 }
 546
 547 /*
 548  * Release the journal device
 549  */
 550 static int ext4_blkdev_put(struct block_device *bdev)
 551 {
 552         bd_release(bdev);
 553         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
 554 }
 555
 556 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 557 {
 558         struct block_device *bdev;
 559         int ret = -ENODEV;
 560
 561         bdev = sbi->journal_bdev;
 562         if (bdev) {
 563                 ret = ext4_blkdev_put(bdev);
 564                 sbi->journal_bdev = NULL;
 565         }
 566         return ret;
 567 }
 568
 569 static inline struct inode *orphan_list_entry(struct list_head *l)
 570 {
 571         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 572 }
 573
 574 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 575 {
 576         struct list_head *l;
 577
 578         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 579                  le32_to_cpu(sbi->s_es->s_last_orphan));
 580
 581         printk(KERN_ERR "sb_info orphan list:\n");
 582         list_for_each(l, &sbi->s_orphan) {
 583                 struct inode *inode = orphan_list_entry(l);
 584                 printk(KERN_ERR "  "
 585                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 586                        inode->i_sb->s_id, inode->i_ino, inode,
 587                        inode->i_mode, inode->i_nlink,
 588                        NEXT_ORPHAN(inode));
 589         }
 590 }
 591
 592 static void ext4_put_super(struct super_block *sb)
 593 {
 594         struct ext4_sb_info *sbi = EXT4_SB(sb);
 595         struct ext4_super_block *es = sbi->s_es;
 596         int i, err;
 597
 598         flush_workqueue(sbi->dio_unwritten_wq);
 599         destroy_workqueue(sbi->dio_unwritten_wq);
 600
 601         lock_super(sb);
 602         lock_kernel();
 603         if (sb->s_dirt)
 604                 ext4_commit_super(sb, 1);
 605
 606         if (sbi->s_journal) {
 607                 err = jbd2_journal_destroy(sbi->s_journal);
 608                 sbi->s_journal = NULL;
 609                 if (err < 0)
 610                         ext4_abort(sb, __func__,
 611                                    "Couldn't clean up the journal");
 612         }
 613
 614         ext4_release_system_zone(sb);
 615         ext4_mb_release(sb);
 616         ext4_ext_release(sb);
 617         ext4_xattr_put_super(sb);
 618
 619         if (!(sb->s_flags & MS_RDONLY)) {
 620                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 621                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 622                 ext4_commit_super(sb, 1);
 623         }
 624         if (sbi->s_proc) {
 625                 remove_proc_entry(sb->s_id, ext4_proc_root);
 626         }
 627         kobject_del(&sbi->s_kobj);
 628
 629         for (i = 0; i < sbi->s_gdb_count; i++)
 630                 brelse(sbi->s_group_desc[i]);
 631         kfree(sbi->s_group_desc);
 632         if (is_vmalloc_addr(sbi->s_flex_groups))
 633                 vfree(sbi->s_flex_groups);
 634         else
 635                 kfree(sbi->s_flex_groups);
 636         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 637         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 638         percpu_counter_destroy(&sbi->s_dirs_counter);
 639         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
 640         brelse(sbi->s_sbh);
 641 #ifdef CONFIG_QUOTA
 642         for (i = 0; i < MAXQUOTAS; i++)
 643                 kfree(sbi->s_qf_names[i]);
 644 #endif
 645
 646         /* Debugging code just in case the in-memory inode orphan list
 647          * isn't empty.  The on-disk one can be non-empty if we've
 648          * detected an error and taken the fs readonly, but the
 649          * in-memory list had better be clean by this point. */
 650         if (!list_empty(&sbi->s_orphan))
 651                 dump_orphan_list(sb, sbi);
 652         J_ASSERT(list_empty(&sbi->s_orphan));
 653
 654         invalidate_bdev(sb->s_bdev);
 655         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 656                 /*
 657                  * Invalidate the journal device's buffers.  We don't want them
 658                  * floating about in memory - the physical journal device may
 659                  * hotswapped, and it breaks the `ro-after' testing code.
 660                  */
 661                 sync_blockdev(sbi->journal_bdev);
 662                 invalidate_bdev(sbi->journal_bdev);
 663                 ext4_blkdev_remove(sbi);
 664         }
 665         sb->s_fs_info = NULL;
 666         /*
 667          * Now that we are completely done shutting down the
 668          * superblock, we need to actually destroy the kobject.
 669          */
 670         unlock_kernel();
 671         unlock_super(sb);
 672         kobject_put(&sbi->s_kobj);
 673         wait_for_completion(&sbi->s_kobj_unregister);
 674         kfree(sbi->s_blockgroup_lock);
 675         kfree(sbi);
 676 }
 677
 678 static struct kmem_cache *ext4_inode_cachep;
 679
 680 /*
 681  * Called inside transaction, so use GFP_NOFS
 682  */
 683 static struct inode *ext4_alloc_inode(struct super_block *sb)
 684 {
 685         struct ext4_inode_info *ei;
 686
 687         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 688         if (!ei)
 689                 return NULL;
 690
 691         ei->vfs_inode.i_version = 1;
 692         ei->vfs_inode.i_data.writeback_index = 0;
 693         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 694         INIT_LIST_HEAD(&ei->i_prealloc_list);
 695         spin_lock_init(&ei->i_prealloc_lock);
 696         /*
 697          * Note:  We can be called before EXT4_SB(sb)->s_journal is set,
 698          * therefore it can be null here.  Don't check it, just initialize
 699          * jinode.
 700          */
 701         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
 702         ei->i_reserved_data_blocks = 0;
 703         ei->i_reserved_meta_blocks = 0;
 704         ei->i_allocated_meta_blocks = 0;
 705         ei->i_da_metadata_calc_len = 0;
 706         ei->i_delalloc_reserved_flag = 0;
 707         spin_lock_init(&(ei->i_block_reservation_lock));
 708 #ifdef CONFIG_QUOTA
 709         ei->i_reserved_quota = 0;
 710 #endif
 711         INIT_LIST_HEAD(&ei->i_aio_dio_complete_list);
 712         ei->cur_aio_dio = NULL;
 713         ei->i_sync_tid = 0;
 714         ei->i_datasync_tid = 0;
 715
 716         return &ei->vfs_inode;
 717 }
 718
 719 static void ext4_destroy_inode(struct inode *inode)
 720 {
 721         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 722                 ext4_msg(inode->i_sb, KERN_ERR,
 723                          "Inode %lu (%p): orphan list check failed!",
 724                          inode->i_ino, EXT4_I(inode));
 725                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 726                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 727                                 true);
 728                 dump_stack();
 729         }
 730         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 731 }
 732
 733 static void init_once(void *foo)
 734 {
 735         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 736
 737         INIT_LIST_HEAD(&ei->i_orphan);
 738 #ifdef CONFIG_EXT4_FS_XATTR
 739         init_rwsem(&ei->xattr_sem);
 740 #endif
 741         init_rwsem(&ei->i_data_sem);
 742         inode_init_once(&ei->vfs_inode);
 743 }
 744
 745 static int init_inodecache(void)
 746 {
 747         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 748                                              sizeof(struct ext4_inode_info),
 749                                              0, (SLAB_RECLAIM_ACCOUNT|
 750                                                 SLAB_MEM_SPREAD),
 751                                              init_once);
 752         if (ext4_inode_cachep == NULL)
 753                 return -ENOMEM;
 754         return 0;
 755 }
 756
 757 static void destroy_inodecache(void)
 758 {
 759         kmem_cache_destroy(ext4_inode_cachep);
 760 }
 761
 762 static void ext4_clear_inode(struct inode *inode)
 763 {
 764         ext4_discard_preallocations(inode);
 765         if (EXT4_JOURNAL(inode))
 766                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
 767                                        &EXT4_I(inode)->jinode);
 768 }
 769
 770 static inline void ext4_show_quota_options(struct seq_file *seq,
 771                                            struct super_block *sb)
 772 {
 773 #if defined(CONFIG_QUOTA)
 774         struct ext4_sb_info *sbi = EXT4_SB(sb);
 775
 776         if (sbi->s_jquota_fmt) {
 777                 char *fmtname = "";
 778
 779                 switch (sbi->s_jquota_fmt) {
 780                 case QFMT_VFS_OLD:
 781                         fmtname = "vfsold";
 782                         break;
 783                 case QFMT_VFS_V0:
 784                         fmtname = "vfsv0";
 785                         break;
 786                 case QFMT_VFS_V1:
 787                         fmtname = "vfsv1";
 788                         break;
 789                 }
 790                 seq_printf(seq, ",jqfmt=%s", fmtname);
 791         }
 792
 793         if (sbi->s_qf_names[USRQUOTA])
 794                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 795
 796         if (sbi->s_qf_names[GRPQUOTA])
 797                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 798
 799         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
 800                 seq_puts(seq, ",usrquota");
 801
 802         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
 803                 seq_puts(seq, ",grpquota");
 804 #endif
 805 }
 806
 807 /*
 808  * Show an option if
 809  *  - it's set to a non-default value OR
 810  *  - if the per-sb default is different from the global default
 811  */
 812 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 813 {
 814         int def_errors;
 815         unsigned long def_mount_opts;
 816         struct super_block *sb = vfs->mnt_sb;
 817         struct ext4_sb_info *sbi = EXT4_SB(sb);
 818         struct ext4_super_block *es = sbi->s_es;
 819
 820         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 821         def_errors     = le16_to_cpu(es->s_errors);
 822
 823         if (sbi->s_sb_block != 1)
 824                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
 825         if (test_opt(sb, MINIX_DF))
 826                 seq_puts(seq, ",minixdf");
 827         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
 828                 seq_puts(seq, ",grpid");
 829         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
 830                 seq_puts(seq, ",nogrpid");
 831         if (sbi->s_resuid != EXT4_DEF_RESUID ||
 832             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
 833                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
 834         }
 835         if (sbi->s_resgid != EXT4_DEF_RESGID ||
 836             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
 837                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
 838         }
 839         if (test_opt(sb, ERRORS_RO)) {
 840                 if (def_errors == EXT4_ERRORS_PANIC ||
 841                     def_errors == EXT4_ERRORS_CONTINUE) {
 842                         seq_puts(seq, ",errors=remount-ro");
 843                 }
 844         }
 845         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
 846                 seq_puts(seq, ",errors=continue");
 847         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
 848                 seq_puts(seq, ",errors=panic");
 849         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
 850                 seq_puts(seq, ",nouid32");
 851         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
 852                 seq_puts(seq, ",debug");
 853         if (test_opt(sb, OLDALLOC))
 854                 seq_puts(seq, ",oldalloc");
 855 #ifdef CONFIG_EXT4_FS_XATTR
 856         if (test_opt(sb, XATTR_USER) &&
 857                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
 858                 seq_puts(seq, ",user_xattr");
 859         if (!test_opt(sb, XATTR_USER) &&
 860             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
 861                 seq_puts(seq, ",nouser_xattr");
 862         }
 863 #endif
 864 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 865         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
 866                 seq_puts(seq, ",acl");
 867         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
 868                 seq_puts(seq, ",noacl");
 869 #endif
 870         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
 871                 seq_printf(seq, ",commit=%u",
 872                            (unsigned) (sbi->s_commit_interval / HZ));
 873         }
 874         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
 875                 seq_printf(seq, ",min_batch_time=%u",
 876                            (unsigned) sbi->s_min_batch_time);
 877         }
 878         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
 879                 seq_printf(seq, ",max_batch_time=%u",
 880                            (unsigned) sbi->s_min_batch_time);
 881         }
 882
 883         /*
 884          * We're changing the default of barrier mount option, so
 885          * let's always display its mount state so it's clear what its
 886          * status is.
 887          */
 888         seq_puts(seq, ",barrier=");
 889         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
 890         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
 891                 seq_puts(seq, ",journal_async_commit");
 892         if (test_opt(sb, NOBH))
 893                 seq_puts(seq, ",nobh");
 894         if (test_opt(sb, I_VERSION))
 895                 seq_puts(seq, ",i_version");
 896         if (!test_opt(sb, DELALLOC))
 897                 seq_puts(seq, ",nodelalloc");
 898
 899
 900         if (sbi->s_stripe)
 901                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
 902         /*
 903          * journal mode get enabled in different ways
 904          * So just print the value even if we didn't specify it
 905          */
 906         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 907                 seq_puts(seq, ",data=journal");
 908         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 909                 seq_puts(seq, ",data=ordered");
 910         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 911                 seq_puts(seq, ",data=writeback");
 912
 913         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
 914                 seq_printf(seq, ",inode_readahead_blks=%u",
 915                            sbi->s_inode_readahead_blks);
 916
 917         if (test_opt(sb, DATA_ERR_ABORT))
 918                 seq_puts(seq, ",data_err=abort");
 919
 920         if (test_opt(sb, NO_AUTO_DA_ALLOC))
 921                 seq_puts(seq, ",noauto_da_alloc");
 922
 923         if (test_opt(sb, DISCARD))
 924                 seq_puts(seq, ",discard");
 925
 926         if (test_opt(sb, NOLOAD))
 927                 seq_puts(seq, ",norecovery");
 928
 929         ext4_show_quota_options(seq, sb);
 930
 931         return 0;
 932 }
 933
 934 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 935                                         u64 ino, u32 generation)
 936 {
 937         struct inode *inode;
 938
 939         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 940                 return ERR_PTR(-ESTALE);
 941         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 942                 return ERR_PTR(-ESTALE);
 943
 944         /* iget isn't really right if the inode is currently unallocated!!
 945          *
 946          * ext4_read_inode will return a bad_inode if the inode had been
 947          * deleted, so we should be safe.
 948          *
 949          * Currently we don't know the generation for parent directory, so
 950          * a generation of 0 means "accept any"
 951          */
 952         inode = ext4_iget(sb, ino);
 953         if (IS_ERR(inode))
 954                 return ERR_CAST(inode);
 955         if (generation && inode->i_generation != generation) {
 956                 iput(inode);
 957                 return ERR_PTR(-ESTALE);
 958         }
 959
 960         return inode;
 961 }
 962
 963 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
 964                                         int fh_len, int fh_type)
 965 {
 966         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 967                                     ext4_nfs_get_inode);
 968 }
 969
 970 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
 971                                         int fh_len, int fh_type)
 972 {
 973         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 974                                     ext4_nfs_get_inode);
 975 }
 976
 977 /*
 978  * Try to release metadata pages (indirect blocks, directories) which are
 979  * mapped via the block device.  Since these pages could have journal heads
 980  * which would prevent try_to_free_buffers() from freeing them, we must use
 981  * jbd2 layer's try_to_free_buffers() function to release them.
 982  */
 983 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
 984                                  gfp_t wait)
 985 {
 986         journal_t *journal = EXT4_SB(sb)->s_journal;
 987
 988         WARN_ON(PageChecked(page));
 989         if (!page_has_buffers(page))
 990                 return 0;
 991         if (journal)
 992                 return jbd2_journal_try_to_free_buffers(journal, page,
 993                                                         wait & ~__GFP_WAIT);
 994         return try_to_free_buffers(page);
 995 }
 996
 997 #ifdef CONFIG_QUOTA
 998 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
 999 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1000
1001 static int ext4_write_dquot(struct dquot *dquot);
1002 static int ext4_acquire_dquot(struct dquot *dquot);
1003 static int ext4_release_dquot(struct dquot *dquot);
1004 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1005 static int ext4_write_info(struct super_block *sb, int type);
1006 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1007                                 char *path, int remount);
1008 static int ext4_quota_on_mount(struct super_block *sb, int type);
1009 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1010                                size_t len, loff_t off);
1011 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1012                                 const char *data, size_t len, loff_t off);
1013
1014 static const struct dquot_operations ext4_quota_operations = {
1015         .initialize     = dquot_initialize,
1016         .drop           = dquot_drop,
1017 #ifdef CONFIG_QUOTA
1018         .get_reserved_space = ext4_get_reserved_space,
1019 #endif
1020         .transfer       = dquot_transfer,
1021         .write_dquot    = ext4_write_dquot,
1022         .acquire_dquot  = ext4_acquire_dquot,
1023         .release_dquot  = ext4_release_dquot,
1024         .mark_dirty     = ext4_mark_dquot_dirty,
1025         .write_info     = ext4_write_info,
1026         .alloc_dquot    = dquot_alloc,
1027         .destroy_dquot  = dquot_destroy,
1028 };
1029
1030 static const struct quotactl_ops ext4_qctl_operations = {
1031         .quota_on       = ext4_quota_on,
1032         .quota_off      = vfs_quota_off,
1033         .quota_sync     = vfs_quota_sync,
1034         .get_info       = vfs_get_dqinfo,
1035         .set_info       = vfs_set_dqinfo,
1036         .get_dqblk      = vfs_get_dqblk,
1037         .set_dqblk      = vfs_set_dqblk
1038 };
1039 #endif
1040
1041 static const struct super_operations ext4_sops = {
1042         .alloc_inode    = ext4_alloc_inode,
1043         .destroy_inode  = ext4_destroy_inode,
1044         .write_inode    = ext4_write_inode,
1045         .dirty_inode    = ext4_dirty_inode,
1046         .delete_inode   = ext4_delete_inode,
1047         .put_super      = ext4_put_super,
1048         .sync_fs        = ext4_sync_fs,
1049         .freeze_fs      = ext4_freeze,
1050         .unfreeze_fs    = ext4_unfreeze,
1051         .statfs         = ext4_statfs,
1052         .remount_fs     = ext4_remount,
1053         .clear_inode    = ext4_clear_inode,
1054         .show_options   = ext4_show_options,
1055 #ifdef CONFIG_QUOTA
1056         .quota_read     = ext4_quota_read,
1057         .quota_write    = ext4_quota_write,
1058 #endif
1059         .bdev_try_to_free_page = bdev_try_to_free_page,
1060 };
1061
1062 static const struct super_operations ext4_nojournal_sops = {
1063         .alloc_inode    = ext4_alloc_inode,
1064         .destroy_inode  = ext4_destroy_inode,
1065         .write_inode    = ext4_write_inode,
1066         .dirty_inode    = ext4_dirty_inode,
1067         .delete_inode   = ext4_delete_inode,
1068         .write_super    = ext4_write_super,
1069         .put_super      = ext4_put_super,
1070         .statfs         = ext4_statfs,
1071         .remount_fs     = ext4_remount,
1072         .clear_inode    = ext4_clear_inode,
1073         .show_options   = ext4_show_options,
1074 #ifdef CONFIG_QUOTA
1075         .quota_read     = ext4_quota_read,
1076         .quota_write    = ext4_quota_write,
1077 #endif
1078         .bdev_try_to_free_page = bdev_try_to_free_page,
1079 };
1080
1081 static const struct export_operations ext4_export_ops = {
1082         .fh_to_dentry = ext4_fh_to_dentry,
1083         .fh_to_parent = ext4_fh_to_parent,
1084         .get_parent = ext4_get_parent,
1085 };
1086
1087 enum {
1088         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1089         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1090         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1091         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1092         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1093         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1094         Opt_journal_update, Opt_journal_dev,
1095         Opt_journal_checksum, Opt_journal_async_commit,
1096         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1097         Opt_data_err_abort, Opt_data_err_ignore,
1098         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1099         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1100         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1101         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1102         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1103         Opt_block_validity, Opt_noblock_validity,
1104         Opt_inode_readahead_blks, Opt_journal_ioprio,
1105         Opt_discard, Opt_nodiscard,
1106 };
1107
1108 static const match_table_t tokens = {
1109         {Opt_bsd_df, "bsddf"},
1110         {Opt_minix_df, "minixdf"},
1111         {Opt_grpid, "grpid"},
1112         {Opt_grpid, "bsdgroups"},
1113         {Opt_nogrpid, "nogrpid"},
1114         {Opt_nogrpid, "sysvgroups"},
1115         {Opt_resgid, "resgid=%u"},
1116         {Opt_resuid, "resuid=%u"},
1117         {Opt_sb, "sb=%u"},
1118         {Opt_err_cont, "errors=continue"},
1119         {Opt_err_panic, "errors=panic"},
1120         {Opt_err_ro, "errors=remount-ro"},
1121         {Opt_nouid32, "nouid32"},
1122         {Opt_debug, "debug"},
1123         {Opt_oldalloc, "oldalloc"},
1124         {Opt_orlov, "orlov"},
1125         {Opt_user_xattr, "user_xattr"},
1126         {Opt_nouser_xattr, "nouser_xattr"},
1127         {Opt_acl, "acl"},
1128         {Opt_noacl, "noacl"},
1129         {Opt_noload, "noload"},
1130         {Opt_noload, "norecovery"},
1131         {Opt_nobh, "nobh"},
1132         {Opt_bh, "bh"},
1133         {Opt_commit, "commit=%u"},
1134         {Opt_min_batch_time, "min_batch_time=%u"},
1135         {Opt_max_batch_time, "max_batch_time=%u"},
1136         {Opt_journal_update, "journal=update"},
1137         {Opt_journal_dev, "journal_dev=%u"},
1138         {Opt_journal_checksum, "journal_checksum"},
1139         {Opt_journal_async_commit, "journal_async_commit"},
1140         {Opt_abort, "abort"},
1141         {Opt_data_journal, "data=journal"},
1142         {Opt_data_ordered, "data=ordered"},
1143         {Opt_data_writeback, "data=writeback"},
1144         {Opt_data_err_abort, "data_err=abort"},
1145         {Opt_data_err_ignore, "data_err=ignore"},
1146         {Opt_offusrjquota, "usrjquota="},
1147         {Opt_usrjquota, "usrjquota=%s"},
1148         {Opt_offgrpjquota, "grpjquota="},
1149         {Opt_grpjquota, "grpjquota=%s"},
1150         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1151         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1152         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1153         {Opt_grpquota, "grpquota"},
1154         {Opt_noquota, "noquota"},
1155         {Opt_quota, "quota"},
1156         {Opt_usrquota, "usrquota"},
1157         {Opt_barrier, "barrier=%u"},
1158         {Opt_barrier, "barrier"},
1159         {Opt_nobarrier, "nobarrier"},
1160         {Opt_i_version, "i_version"},
1161         {Opt_stripe, "stripe=%u"},
1162         {Opt_resize, "resize"},
1163         {Opt_delalloc, "delalloc"},
1164         {Opt_nodelalloc, "nodelalloc"},
1165         {Opt_block_validity, "block_validity"},
1166         {Opt_noblock_validity, "noblock_validity"},
1167         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1168         {Opt_journal_ioprio, "journal_ioprio=%u"},
1169         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1170         {Opt_auto_da_alloc, "auto_da_alloc"},
1171         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1172         {Opt_discard, "discard"},
1173         {Opt_nodiscard, "nodiscard"},
1174         {Opt_err, NULL},
1175 };
1176
1177 static ext4_fsblk_t get_sb_block(void **data)
1178 {
1179         ext4_fsblk_t    sb_block;
1180         char            *options = (char *) *data;
1181
1182         if (!options || strncmp(options, "sb=", 3) != 0)
1183                 return 1;       /* Default location */
1184
1185         options += 3;
1186         /* TODO: use simple_strtoll with >32bit ext4 */
1187         sb_block = simple_strtoul(options, &options, 0);
1188         if (*options && *options != ',') {
1189                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1190                        (char *) *data);
1191                 return 1;
1192         }
1193         if (*options == ',')
1194                 options++;
1195         *data = (void *) options;
1196
1197         return sb_block;
1198 }
1199
1200 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1201
1202 static int parse_options(char *options, struct super_block *sb,
1203                          unsigned long *journal_devnum,
1204                          unsigned int *journal_ioprio,
1205                          ext4_fsblk_t *n_blocks_count, int is_remount)
1206 {
1207         struct ext4_sb_info *sbi = EXT4_SB(sb);
1208         char *p;
1209         substring_t args[MAX_OPT_ARGS];
1210         int data_opt = 0;
1211         int option;
1212 #ifdef CONFIG_QUOTA
1213         int qtype, qfmt;
1214         char *qname;
1215 #endif
1216
1217         if (!options)
1218                 return 1;
1219
1220         while ((p = strsep(&options, ",")) != NULL) {
1221                 int token;
1222                 if (!*p)
1223                         continue;
1224
1225                 token = match_token(p, tokens, args);
1226                 switch (token) {
1227                 case Opt_bsd_df:
1228                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1229                         break;
1230                 case Opt_minix_df:
1231                         set_opt(sbi->s_mount_opt, MINIX_DF);
1232                         break;
1233                 case Opt_grpid:
1234                         set_opt(sbi->s_mount_opt, GRPID);
1235                         break;
1236                 case Opt_nogrpid:
1237                         clear_opt(sbi->s_mount_opt, GRPID);
1238                         break;
1239                 case Opt_resuid:
1240                         if (match_int(&args[0], &option))
1241                                 return 0;
1242                         sbi->s_resuid = option;
1243                         break;
1244                 case Opt_resgid:
1245                         if (match_int(&args[0], &option))
1246                                 return 0;
1247                         sbi->s_resgid = option;
1248                         break;
1249                 case Opt_sb:
1250                         /* handled by get_sb_block() instead of here */
1251                         /* *sb_block = match_int(&args[0]); */
1252                         break;
1253                 case Opt_err_panic:
1254                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1255                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1256                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1257                         break;
1258                 case Opt_err_ro:
1259                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1260                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1261                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1262                         break;
1263                 case Opt_err_cont:
1264                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1265                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1266                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1267                         break;
1268                 case Opt_nouid32:
1269                         set_opt(sbi->s_mount_opt, NO_UID32);
1270                         break;
1271                 case Opt_debug:
1272                         set_opt(sbi->s_mount_opt, DEBUG);
1273                         break;
1274                 case Opt_oldalloc:
1275                         set_opt(sbi->s_mount_opt, OLDALLOC);
1276                         break;
1277                 case Opt_orlov:
1278                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1279                         break;
1280 #ifdef CONFIG_EXT4_FS_XATTR
1281                 case Opt_user_xattr:
1282                         set_opt(sbi->s_mount_opt, XATTR_USER);
1283                         break;
1284                 case Opt_nouser_xattr:
1285                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1286                         break;
1287 #else
1288                 case Opt_user_xattr:
1289                 case Opt_nouser_xattr:
1290                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1291                         break;
1292 #endif
1293 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1294                 case Opt_acl:
1295                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1296                         break;
1297                 case Opt_noacl:
1298                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1299                         break;
1300 #else
1301                 case Opt_acl:
1302                 case Opt_noacl:
1303                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1304                         break;
1305 #endif
1306                 case Opt_journal_update:
1307                         /* @@@ FIXME */
1308                         /* Eventually we will want to be able to create
1309                            a journal file here.  For now, only allow the
1310                            user to specify an existing inode to be the
1311                            journal file. */
1312                         if (is_remount) {
1313                                 ext4_msg(sb, KERN_ERR,
1314                                          "Cannot specify journal on remount");
1315                                 return 0;
1316                         }
1317                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1318                         break;
1319                 case Opt_journal_dev:
1320                         if (is_remount) {
1321                                 ext4_msg(sb, KERN_ERR,
1322                                         "Cannot specify journal on remount");
1323                                 return 0;
1324                         }
1325                         if (match_int(&args[0], &option))
1326                                 return 0;
1327                         *journal_devnum = option;
1328                         break;
1329                 case Opt_journal_checksum:
1330                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1331                         break;
1332                 case Opt_journal_async_commit:
1333                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1334                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1335                         break;
1336                 case Opt_noload:
1337                         set_opt(sbi->s_mount_opt, NOLOAD);
1338                         break;
1339                 case Opt_commit:
1340                         if (match_int(&args[0], &option))
1341                                 return 0;
1342                         if (option < 0)
1343                                 return 0;
1344                         if (option == 0)
1345                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1346                         sbi->s_commit_interval = HZ * option;
1347                         break;
1348                 case Opt_max_batch_time:
1349                         if (match_int(&args[0], &option))
1350                                 return 0;
1351                         if (option < 0)
1352                                 return 0;
1353                         if (option == 0)
1354                                 option = EXT4_DEF_MAX_BATCH_TIME;
1355                         sbi->s_max_batch_time = option;
1356                         break;
1357                 case Opt_min_batch_time:
1358                         if (match_int(&args[0], &option))
1359                                 return 0;
1360                         if (option < 0)
1361                                 return 0;
1362                         sbi->s_min_batch_time = option;
1363                         break;
1364                 case Opt_data_journal:
1365                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1366                         goto datacheck;
1367                 case Opt_data_ordered:
1368                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1369                         goto datacheck;
1370                 case Opt_data_writeback:
1371                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1372                 datacheck:
1373                         if (is_remount) {
1374                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1375                                                 != data_opt) {
1376                                         ext4_msg(sb, KERN_ERR,
1377                                                 "Cannot change data mode on remount");
1378                                         return 0;
1379                                 }
1380                         } else {
1381                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1382                                 sbi->s_mount_opt |= data_opt;
1383                         }
1384                         break;
1385                 case Opt_data_err_abort:
1386                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1387                         break;
1388                 case Opt_data_err_ignore:
1389                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1390                         break;
1391 #ifdef CONFIG_QUOTA
1392                 case Opt_usrjquota:
1393                         qtype = USRQUOTA;
1394                         goto set_qf_name;
1395                 case Opt_grpjquota:
1396                         qtype = GRPQUOTA;
1397 set_qf_name:
1398                         if (sb_any_quota_loaded(sb) &&
1399                             !sbi->s_qf_names[qtype]) {
1400                                 ext4_msg(sb, KERN_ERR,
1401                                        "Cannot change journaled "
1402                                        "quota options when quota turned on");
1403                                 return 0;
1404                         }
1405                         qname = match_strdup(&args[0]);
1406                         if (!qname) {
1407                                 ext4_msg(sb, KERN_ERR,
1408                                         "Not enough memory for "
1409                                         "storing quotafile name");
1410                                 return 0;
1411                         }
1412                         if (sbi->s_qf_names[qtype] &&
1413                             strcmp(sbi->s_qf_names[qtype], qname)) {
1414                                 ext4_msg(sb, KERN_ERR,
1415                                         "%s quota file already "
1416                                         "specified", QTYPE2NAME(qtype));
1417                                 kfree(qname);
1418                                 return 0;
1419                         }
1420                         sbi->s_qf_names[qtype] = qname;
1421                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1422                                 ext4_msg(sb, KERN_ERR,
1423                                         "quotafile must be on "
1424                                         "filesystem root");
1425                                 kfree(sbi->s_qf_names[qtype]);
1426                                 sbi->s_qf_names[qtype] = NULL;
1427                                 return 0;
1428                         }
1429                         set_opt(sbi->s_mount_opt, QUOTA);
1430                         break;
1431                 case Opt_offusrjquota:
1432                         qtype = USRQUOTA;
1433                         goto clear_qf_name;
1434                 case Opt_offgrpjquota:
1435                         qtype = GRPQUOTA;
1436 clear_qf_name:
1437                         if (sb_any_quota_loaded(sb) &&
1438                             sbi->s_qf_names[qtype]) {
1439                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1440                                         "journaled quota options when "
1441                                         "quota turned on");
1442                                 return 0;
1443                         }
1444                         /*
1445                          * The space will be released later when all options
1446                          * are confirmed to be correct
1447                          */
1448                         sbi->s_qf_names[qtype] = NULL;
1449                         break;
1450                 case Opt_jqfmt_vfsold:
1451                         qfmt = QFMT_VFS_OLD;
1452                         goto set_qf_format;
1453                 case Opt_jqfmt_vfsv0:
1454                         qfmt = QFMT_VFS_V0;
1455                         goto set_qf_format;
1456                 case Opt_jqfmt_vfsv1:
1457                         qfmt = QFMT_VFS_V1;
1458 set_qf_format:
1459                         if (sb_any_quota_loaded(sb) &&
1460                             sbi->s_jquota_fmt != qfmt) {
1461                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1462                                         "journaled quota options when "
1463                                         "quota turned on");
1464                                 return 0;
1465                         }
1466                         sbi->s_jquota_fmt = qfmt;
1467                         break;
1468                 case Opt_quota:
1469                 case Opt_usrquota:
1470                         set_opt(sbi->s_mount_opt, QUOTA);
1471                         set_opt(sbi->s_mount_opt, USRQUOTA);
1472                         break;
1473                 case Opt_grpquota:
1474                         set_opt(sbi->s_mount_opt, QUOTA);
1475                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1476                         break;
1477                 case Opt_noquota:
1478                         if (sb_any_quota_loaded(sb)) {
1479                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1480                                         "options when quota turned on");
1481                                 return 0;
1482                         }
1483                         clear_opt(sbi->s_mount_opt, QUOTA);
1484                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1485                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1486                         break;
1487 #else
1488                 case Opt_quota:
1489                 case Opt_usrquota:
1490                 case Opt_grpquota:
1491                         ext4_msg(sb, KERN_ERR,
1492                                 "quota options not supported");
1493                         break;
1494                 case Opt_usrjquota:
1495                 case Opt_grpjquota:
1496                 case Opt_offusrjquota:
1497                 case Opt_offgrpjquota:
1498                 case Opt_jqfmt_vfsold:
1499                 case Opt_jqfmt_vfsv0:
1500                 case Opt_jqfmt_vfsv1:
1501                         ext4_msg(sb, KERN_ERR,
1502                                 "journaled quota options not supported");
1503                         break;
1504                 case Opt_noquota:
1505                         break;
1506 #endif
1507                 case Opt_abort:
1508                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1509                         break;
1510                 case Opt_nobarrier:
1511                         clear_opt(sbi->s_mount_opt, BARRIER);
1512                         break;
1513                 case Opt_barrier:
1514                         if (match_int(&args[0], &option)) {
1515                                 set_opt(sbi->s_mount_opt, BARRIER);
1516                                 break;
1517                         }
1518                         if (option)
1519                                 set_opt(sbi->s_mount_opt, BARRIER);
1520                         else
1521                                 clear_opt(sbi->s_mount_opt, BARRIER);
1522                         break;
1523                 case Opt_ignore:
1524                         break;
1525                 case Opt_resize:
1526                         if (!is_remount) {
1527                                 ext4_msg(sb, KERN_ERR,
1528                                         "resize option only available "
1529                                         "for remount");
1530                                 return 0;
1531                         }
1532                         if (match_int(&args[0], &option) != 0)
1533                                 return 0;
1534                         *n_blocks_count = option;
1535                         break;
1536                 case Opt_nobh:
1537                         set_opt(sbi->s_mount_opt, NOBH);
1538                         break;
1539                 case Opt_bh:
1540                         clear_opt(sbi->s_mount_opt, NOBH);
1541                         break;
1542                 case Opt_i_version:
1543                         set_opt(sbi->s_mount_opt, I_VERSION);
1544                         sb->s_flags |= MS_I_VERSION;
1545                         break;
1546                 case Opt_nodelalloc:
1547                         clear_opt(sbi->s_mount_opt, DELALLOC);
1548                         break;
1549                 case Opt_stripe:
1550                         if (match_int(&args[0], &option))
1551                                 return 0;
1552                         if (option < 0)
1553                                 return 0;
1554                         sbi->s_stripe = option;
1555                         break;
1556                 case Opt_delalloc:
1557                         set_opt(sbi->s_mount_opt, DELALLOC);
1558                         break;
1559                 case Opt_block_validity:
1560                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1561                         break;
1562                 case Opt_noblock_validity:
1563                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1564                         break;
1565                 case Opt_inode_readahead_blks:
1566                         if (match_int(&args[0], &option))
1567                                 return 0;
1568                         if (option < 0 || option > (1 << 30))
1569                                 return 0;
1570                         if (!is_power_of_2(option)) {
1571                                 ext4_msg(sb, KERN_ERR,
1572                                          "EXT4-fs: inode_readahead_blks"
1573                                          " must be a power of 2");
1574                                 return 0;
1575                         }
1576                         sbi->s_inode_readahead_blks = option;
1577                         break;
1578                 case Opt_journal_ioprio:
1579                         if (match_int(&args[0], &option))
1580                                 return 0;
1581                         if (option < 0 || option > 7)
1582                                 break;
1583                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1584                                                             option);
1585                         break;
1586                 case Opt_noauto_da_alloc:
1587                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1588                         break;
1589                 case Opt_auto_da_alloc:
1590                         if (match_int(&args[0], &option)) {
1591                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1592                                 break;
1593                         }
1594                         if (option)
1595                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1596                         else
1597                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1598                         break;
1599                 case Opt_discard:
1600                         set_opt(sbi->s_mount_opt, DISCARD);
1601                         break;
1602                 case Opt_nodiscard:
1603                         clear_opt(sbi->s_mount_opt, DISCARD);
1604                         break;
1605                 default:
1606                         ext4_msg(sb, KERN_ERR,
1607                                "Unrecognized mount option \"%s\" "
1608                                "or missing value", p);
1609                         return 0;
1610                 }
1611         }
1612 #ifdef CONFIG_QUOTA
1613         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1614                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1615                      sbi->s_qf_names[USRQUOTA])
1616                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1617
1618                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1619                      sbi->s_qf_names[GRPQUOTA])
1620                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1621
1622                 if ((sbi->s_qf_names[USRQUOTA] &&
1623                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1624                     (sbi->s_qf_names[GRPQUOTA] &&
1625                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1626                         ext4_msg(sb, KERN_ERR, "old and new quota "
1627                                         "format mixing");
1628                         return 0;
1629                 }
1630
1631                 if (!sbi->s_jquota_fmt) {
1632                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1633                                         "not specified");
1634                         return 0;
1635                 }
1636         } else {
1637                 if (sbi->s_jquota_fmt) {
1638                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1639                                         "specified with no journaling "
1640                                         "enabled");
1641                         return 0;
1642                 }
1643         }
1644 #endif
1645         return 1;
1646 }
1647
1648 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1649                             int read_only)
1650 {
1651         struct ext4_sb_info *sbi = EXT4_SB(sb);
1652         int res = 0;
1653
1654         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1655                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1656                          "forcing read-only mode");
1657                 res = MS_RDONLY;
1658         }
1659         if (read_only)
1660                 return res;
1661         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1662                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1663                          "running e2fsck is recommended");
1664         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1665                 ext4_msg(sb, KERN_WARNING,
1666                          "warning: mounting fs with errors, "
1667                          "running e2fsck is recommended");
1668         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1669                  le16_to_cpu(es->s_mnt_count) >=
1670                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1671                 ext4_msg(sb, KERN_WARNING,
1672                          "warning: maximal mount count reached, "
1673                          "running e2fsck is recommended");
1674         else if (le32_to_cpu(es->s_checkinterval) &&
1675                 (le32_to_cpu(es->s_lastcheck) +
1676                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1677                 ext4_msg(sb, KERN_WARNING,
1678                          "warning: checktime reached, "
1679                          "running e2fsck is recommended");
1680         if (!sbi->s_journal)
1681                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1682         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1683                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1684         le16_add_cpu(&es->s_mnt_count, 1);
1685         es->s_mtime = cpu_to_le32(get_seconds());
1686         ext4_update_dynamic_rev(sb);
1687         if (sbi->s_journal)
1688                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1689
1690         ext4_commit_super(sb, 1);
1691         if (test_opt(sb, DEBUG))
1692                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1693                                 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1694                         sb->s_blocksize,
1695                         sbi->s_groups_count,
1696                         EXT4_BLOCKS_PER_GROUP(sb),
1697                         EXT4_INODES_PER_GROUP(sb),
1698                         sbi->s_mount_opt);
1699
1700         return res;
1701 }
1702
1703 static int ext4_fill_flex_info(struct super_block *sb)
1704 {
1705         struct ext4_sb_info *sbi = EXT4_SB(sb);
1706         struct ext4_group_desc *gdp = NULL;
1707         ext4_group_t flex_group_count;
1708         ext4_group_t flex_group;
1709         int groups_per_flex = 0;
1710         size_t size;
1711         int i;
1712
1713         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1714         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1715
1716         if (groups_per_flex < 2) {
1717                 sbi->s_log_groups_per_flex = 0;
1718                 return 1;
1719         }
1720
1721         /* We allocate both existing and potentially added groups */
1722         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1723                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1724                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1725         size = flex_group_count * sizeof(struct flex_groups);
1726         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1727         if (sbi->s_flex_groups == NULL) {
1728                 sbi->s_flex_groups = vmalloc(size);
1729                 if (sbi->s_flex_groups)
1730                         memset(sbi->s_flex_groups, 0, size);
1731         }
1732         if (sbi->s_flex_groups == NULL) {
1733                 ext4_msg(sb, KERN_ERR, "not enough memory for "
1734                                 "%u flex groups", flex_group_count);
1735                 goto failed;
1736         }
1737
1738         for (i = 0; i < sbi->s_groups_count; i++) {
1739                 gdp = ext4_get_group_desc(sb, i, NULL);
1740
1741                 flex_group = ext4_flex_group(sbi, i);
1742                 atomic_add(ext4_free_inodes_count(sb, gdp),
1743                            &sbi->s_flex_groups[flex_group].free_inodes);
1744                 atomic_add(ext4_free_blks_count(sb, gdp),
1745                            &sbi->s_flex_groups[flex_group].free_blocks);
1746                 atomic_add(ext4_used_dirs_count(sb, gdp),
1747                            &sbi->s_flex_groups[flex_group].used_dirs);
1748         }
1749
1750         return 1;
1751 failed:
1752         return 0;
1753 }
1754
1755 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1756                             struct ext4_group_desc *gdp)
1757 {
1758         __u16 crc = 0;
1759
1760         if (sbi->s_es->s_feature_ro_compat &
1761             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1762                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1763                 __le32 le_group = cpu_to_le32(block_group);
1764
1765                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1766                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1767                 crc = crc16(crc, (__u8 *)gdp, offset);
1768                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1769                 /* for checksum of struct ext4_group_desc do the rest...*/
1770                 if ((sbi->s_es->s_feature_incompat &
1771                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1772                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1773                         crc = crc16(crc, (__u8 *)gdp + offset,
1774                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1775                                         offset);
1776         }
1777
1778         return cpu_to_le16(crc);
1779 }
1780
1781 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1782                                 struct ext4_group_desc *gdp)
1783 {
1784         if ((sbi->s_es->s_feature_ro_compat &
1785              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1786             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1787                 return 0;
1788
1789         return 1;
1790 }
1791
1792 /* Called at mount-time, super-block is locked */
1793 static int ext4_check_descriptors(struct super_block *sb)
1794 {
1795         struct ext4_sb_info *sbi = EXT4_SB(sb);
1796         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1797         ext4_fsblk_t last_block;
1798         ext4_fsblk_t block_bitmap;
1799         ext4_fsblk_t inode_bitmap;
1800         ext4_fsblk_t inode_table;
1801         int flexbg_flag = 0;
1802         ext4_group_t i;
1803
1804         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1805                 flexbg_flag = 1;
1806
1807         ext4_debug("Checking group descriptors");
1808
1809         for (i = 0; i < sbi->s_groups_count; i++) {
1810                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1811
1812                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1813                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1814                 else
1815                         last_block = first_block +
1816                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1817
1818                 block_bitmap = ext4_block_bitmap(sb, gdp);
1819                 if (block_bitmap < first_block || block_bitmap > last_block) {
1820                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1821                                "Block bitmap for group %u not in group "
1822                                "(block %llu)!", i, block_bitmap);
1823                         return 0;
1824                 }
1825                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1826                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1827                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1828                                "Inode bitmap for group %u not in group "
1829                                "(block %llu)!", i, inode_bitmap);
1830                         return 0;
1831                 }
1832                 inode_table = ext4_inode_table(sb, gdp);
1833                 if (inode_table < first_block ||
1834                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1835                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1836                                "Inode table for group %u not in group "
1837                                "(block %llu)!", i, inode_table);
1838                         return 0;
1839                 }
1840                 ext4_lock_group(sb, i);
1841                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1842                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1843                                  "Checksum for group %u failed (%u!=%u)",
1844                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1845                                      gdp)), le16_to_cpu(gdp->bg_checksum));
1846                         if (!(sb->s_flags & MS_RDONLY)) {
1847                                 ext4_unlock_group(sb, i);
1848                                 return 0;
1849                         }
1850                 }
1851                 ext4_unlock_group(sb, i);
1852                 if (!flexbg_flag)
1853                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1854         }
1855
1856         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1857         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1858         return 1;
1859 }
1860
1861 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1862  * the superblock) which were deleted from all directories, but held open by
1863  * a process at the time of a crash.  We walk the list and try to delete these
1864  * inodes at recovery time (only with a read-write filesystem).
1865  *
1866  * In order to keep the orphan inode chain consistent during traversal (in
1867  * case of crash during recovery), we link each inode into the superblock
1868  * orphan list_head and handle it the same way as an inode deletion during
1869  * normal operation (which journals the operations for us).
1870  *
1871  * We only do an iget() and an iput() on each inode, which is very safe if we
1872  * accidentally point at an in-use or already deleted inode.  The worst that
1873  * can happen in this case is that we get a "bit already cleared" message from
1874  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1875  * e2fsck was run on this filesystem, and it must have already done the orphan
1876  * inode cleanup for us, so we can safely abort without any further action.
1877  */
1878 static void ext4_orphan_cleanup(struct super_block *sb,
1879                                 struct ext4_super_block *es)
1880 {
1881         unsigned int s_flags = sb->s_flags;
1882         int nr_orphans = 0, nr_truncates = 0;
1883 #ifdef CONFIG_QUOTA
1884         int i;
1885 #endif
1886         if (!es->s_last_orphan) {
1887                 jbd_debug(4, "no orphan inodes to clean up\n");
1888                 return;
1889         }
1890
1891         if (bdev_read_only(sb->s_bdev)) {
1892                 ext4_msg(sb, KERN_ERR, "write access "
1893                         "unavailable, skipping orphan cleanup");
1894                 return;
1895         }
1896
1897         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1898                 if (es->s_last_orphan)
1899                         jbd_debug(1, "Errors on filesystem, "
1900                                   "clearing orphan list.\n");
1901                 es->s_last_orphan = 0;
1902                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1903                 return;
1904         }
1905
1906         if (s_flags & MS_RDONLY) {
1907                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
1908                 sb->s_flags &= ~MS_RDONLY;
1909         }
1910 #ifdef CONFIG_QUOTA
1911         /* Needed for iput() to work correctly and not trash data */
1912         sb->s_flags |= MS_ACTIVE;
1913         /* Turn on quotas so that they are updated correctly */
1914         for (i = 0; i < MAXQUOTAS; i++) {
1915                 if (EXT4_SB(sb)->s_qf_names[i]) {
1916                         int ret = ext4_quota_on_mount(sb, i);
1917                         if (ret < 0)
1918                                 ext4_msg(sb, KERN_ERR,
1919                                         "Cannot turn on journaled "
1920                                         "quota: error %d", ret);
1921                 }
1922         }
1923 #endif
1924
1925         while (es->s_last_orphan) {
1926                 struct inode *inode;
1927
1928                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1929                 if (IS_ERR(inode)) {
1930                         es->s_last_orphan = 0;
1931                         break;
1932                 }
1933
1934                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1935                 vfs_dq_init(inode);
1936                 if (inode->i_nlink) {
1937                         ext4_msg(sb, KERN_DEBUG,
1938                                 "%s: truncating inode %lu to %lld bytes",
1939                                 __func__, inode->i_ino, inode->i_size);
1940                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1941                                   inode->i_ino, inode->i_size);
1942                         ext4_truncate(inode);
1943                         nr_truncates++;
1944                 } else {
1945                         ext4_msg(sb, KERN_DEBUG,
1946                                 "%s: deleting unreferenced inode %lu",
1947                                 __func__, inode->i_ino);
1948                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1949                                   inode->i_ino);
1950                         nr_orphans++;
1951                 }
1952                 iput(inode);  /* The delete magic happens here! */
1953         }
1954
1955 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1956
1957         if (nr_orphans)
1958                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
1959                        PLURAL(nr_orphans));
1960         if (nr_truncates)
1961                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
1962                        PLURAL(nr_truncates));
1963 #ifdef CONFIG_QUOTA
1964         /* Turn quotas off */
1965         for (i = 0; i < MAXQUOTAS; i++) {
1966                 if (sb_dqopt(sb)->files[i])
1967                         vfs_quota_off(sb, i, 0);
1968         }
1969 #endif
1970         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1971 }
1972
1973 /*
1974  * Maximal extent format file size.
1975  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1976  * extent format containers, within a sector_t, and within i_blocks
1977  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1978  * so that won't be a limiting factor.
1979  *
1980  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1981  */
1982 static loff_t ext4_max_size(int blkbits, int has_huge_files)
1983 {
1984         loff_t res;
1985         loff_t upper_limit = MAX_LFS_FILESIZE;
1986
1987         /* small i_blocks in vfs inode? */
1988         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1989                 /*
1990                  * CONFIG_LBDAF is not enabled implies the inode
1991                  * i_block represent total blocks in 512 bytes
1992                  * 32 == size of vfs inode i_blocks * 8
1993                  */
1994                 upper_limit = (1LL << 32) - 1;
1995
1996                 /* total blocks in file system block size */
1997                 upper_limit >>= (blkbits - 9);
1998                 upper_limit <<= blkbits;
1999         }
2000
2001         /* 32-bit extent-start container, ee_block */
2002         res = 1LL << 32;
2003         res <<= blkbits;
2004         res -= 1;
2005
2006         /* Sanity check against vm- & vfs- imposed limits */
2007         if (res > upper_limit)
2008                 res = upper_limit;
2009
2010         return res;
2011 }
2012
2013 /*
2014  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2015  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2016  * We need to be 1 filesystem block less than the 2^48 sector limit.
2017  */
2018 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2019 {
2020         loff_t res = EXT4_NDIR_BLOCKS;
2021         int meta_blocks;
2022         loff_t upper_limit;
2023         /* This is calculated to be the largest file size for a dense, block
2024          * mapped file such that the file's total number of 512-byte sectors,
2025          * including data and all indirect blocks, does not exceed (2^48 - 1).
2026          *
2027          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2028          * number of 512-byte sectors of the file.
2029          */
2030
2031         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2032                 /*
2033                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2034                  * the inode i_block field represents total file blocks in
2035                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2036                  */
2037                 upper_limit = (1LL << 32) - 1;
2038
2039                 /* total blocks in file system block size */
2040                 upper_limit >>= (bits - 9);
2041
2042         } else {
2043                 /*
2044                  * We use 48 bit ext4_inode i_blocks
2045                  * With EXT4_HUGE_FILE_FL set the i_blocks
2046                  * represent total number of blocks in
2047                  * file system block size
2048                  */
2049                 upper_limit = (1LL << 48) - 1;
2050
2051         }
2052
2053         /* indirect blocks */
2054         meta_blocks = 1;
2055         /* double indirect blocks */
2056         meta_blocks += 1 + (1LL << (bits-2));
2057         /* tripple indirect blocks */
2058         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2059
2060         upper_limit -= meta_blocks;
2061         upper_limit <<= bits;
2062
2063         res += 1LL << (bits-2);
2064         res += 1LL << (2*(bits-2));
2065         res += 1LL << (3*(bits-2));
2066         res <<= bits;
2067         if (res > upper_limit)
2068                 res = upper_limit;
2069
2070         if (res > MAX_LFS_FILESIZE)
2071                 res = MAX_LFS_FILESIZE;
2072
2073         return res;
2074 }
2075
2076 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2077                                    ext4_fsblk_t logical_sb_block, int nr)
2078 {
2079         struct ext4_sb_info *sbi = EXT4_SB(sb);
2080         ext4_group_t bg, first_meta_bg;
2081         int has_super = 0;
2082
2083         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2084
2085         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2086             nr < first_meta_bg)
2087                 return logical_sb_block + nr + 1;
2088         bg = sbi->s_desc_per_block * nr;
2089         if (ext4_bg_has_super(sb, bg))
2090                 has_super = 1;
2091
2092         return (has_super + ext4_group_first_block_no(sb, bg));
2093 }
2094
2095 /**
2096  * ext4_get_stripe_size: Get the stripe size.
2097  * @sbi: In memory super block info
2098  *
2099  * If we have specified it via mount option, then
2100  * use the mount option value. If the value specified at mount time is
2101  * greater than the blocks per group use the super block value.
2102  * If the super block value is greater than blocks per group return 0.
2103  * Allocator needs it be less than blocks per group.
2104  *
2105  */
2106 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2107 {
2108         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2109         unsigned long stripe_width =
2110                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2111
2112         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2113                 return sbi->s_stripe;
2114
2115         if (stripe_width <= sbi->s_blocks_per_group)
2116                 return stripe_width;
2117
2118         if (stride <= sbi->s_blocks_per_group)
2119                 return stride;
2120
2121         return 0;
2122 }
2123
2124 /* sysfs supprt */
2125
2126 struct ext4_attr {
2127         struct attribute attr;
2128         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2129         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2130                          const char *, size_t);
2131         int offset;
2132 };
2133
2134 static int parse_strtoul(const char *buf,
2135                 unsigned long max, unsigned long *value)
2136 {
2137         char *endp;
2138
2139         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2140         endp = skip_spaces(endp);
2141         if (*endp || *value > max)
2142                 return -EINVAL;
2143
2144         return 0;
2145 }
2146
2147 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2148                                               struct ext4_sb_info *sbi,
2149                                               char *buf)
2150 {
2151         return snprintf(buf, PAGE_SIZE, "%llu\n",
2152                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2153 }
2154
2155 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2156                                          struct ext4_sb_info *sbi, char *buf)
2157 {
2158         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2159
2160         return snprintf(buf, PAGE_SIZE, "%lu\n",
2161                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2162                          sbi->s_sectors_written_start) >> 1);
2163 }
2164
2165 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2166                                           struct ext4_sb_info *sbi, char *buf)
2167 {
2168         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2169
2170         return snprintf(buf, PAGE_SIZE, "%llu\n",
2171                         (unsigned long long)(sbi->s_kbytes_written +
2172                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2173                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2174 }
2175
2176 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2177                                           struct ext4_sb_info *sbi,
2178                                           const char *buf, size_t count)
2179 {
2180         unsigned long t;
2181
2182         if (parse_strtoul(buf, 0x40000000, &t))
2183                 return -EINVAL;
2184
2185         if (!is_power_of_2(t))
2186                 return -EINVAL;
2187
2188         sbi->s_inode_readahead_blks = t;
2189         return count;
2190 }
2191
2192 static ssize_t sbi_ui_show(struct ext4_attr *a,
2193                            struct ext4_sb_info *sbi, char *buf)
2194 {
2195         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2196
2197         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2198 }
2199
2200 static ssize_t sbi_ui_store(struct ext4_attr *a,
2201                             struct ext4_sb_info *sbi,
2202                             const char *buf, size_t count)
2203 {
2204         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2205         unsigned long t;
2206
2207         if (parse_strtoul(buf, 0xffffffff, &t))
2208                 return -EINVAL;
2209         *ui = t;
2210         return count;
2211 }
2212
2213 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2214 static struct ext4_attr ext4_attr_##_name = {                   \
2215         .attr = {.name = __stringify(_name), .mode = _mode },   \
2216         .show   = _show,                                        \
2217         .store  = _store,                                       \
2218         .offset = offsetof(struct ext4_sb_info, _elname),       \
2219 }
2220 #define EXT4_ATTR(name, mode, show, store) \
2221 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2222
2223 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2224 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2225 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2226         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2227 #define ATTR_LIST(name) &ext4_attr_##name.attr
2228
2229 EXT4_RO_ATTR(delayed_allocation_blocks);
2230 EXT4_RO_ATTR(session_write_kbytes);
2231 EXT4_RO_ATTR(lifetime_write_kbytes);
2232 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2233                  inode_readahead_blks_store, s_inode_readahead_blks);
2234 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2235 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2236 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2237 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2238 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2239 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2240 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2241 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2242
2243 static struct attribute *ext4_attrs[] = {
2244         ATTR_LIST(delayed_allocation_blocks),
2245         ATTR_LIST(session_write_kbytes),
2246         ATTR_LIST(lifetime_write_kbytes),
2247         ATTR_LIST(inode_readahead_blks),
2248         ATTR_LIST(inode_goal),
2249         ATTR_LIST(mb_stats),
2250         ATTR_LIST(mb_max_to_scan),
2251         ATTR_LIST(mb_min_to_scan),
2252         ATTR_LIST(mb_order2_req),
2253         ATTR_LIST(mb_stream_req),
2254         ATTR_LIST(mb_group_prealloc),
2255         ATTR_LIST(max_writeback_mb_bump),
2256         NULL,
2257 };
2258
2259 static ssize_t ext4_attr_show(struct kobject *kobj,
2260                               struct attribute *attr, char *buf)
2261 {
2262         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2263                                                 s_kobj);
2264         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2265
2266         return a->show ? a->show(a, sbi, buf) : 0;
2267 }
2268
2269 static ssize_t ext4_attr_store(struct kobject *kobj,
2270                                struct attribute *attr,
2271                                const char *buf, size_t len)
2272 {
2273         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2274                                                 s_kobj);
2275         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2276
2277         return a->store ? a->store(a, sbi, buf, len) : 0;
2278 }
2279
2280 static void ext4_sb_release(struct kobject *kobj)
2281 {
2282         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2283                                                 s_kobj);
2284         complete(&sbi->s_kobj_unregister);
2285 }
2286
2287
2288 static struct sysfs_ops ext4_attr_ops = {
2289         .show   = ext4_attr_show,
2290         .store  = ext4_attr_store,
2291 };
2292
2293 static struct kobj_type ext4_ktype = {
2294         .default_attrs  = ext4_attrs,
2295         .sysfs_ops      = &ext4_attr_ops,
2296         .release        = ext4_sb_release,
2297 };
2298
2299 /*
2300  * Check whether this filesystem can be mounted based on
2301  * the features present and the RDONLY/RDWR mount requested.
2302  * Returns 1 if this filesystem can be mounted as requested,
2303  * 0 if it cannot be.
2304  */
2305 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2306 {
2307         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2308                 ext4_msg(sb, KERN_ERR,
2309                         "Couldn't mount because of "
2310                         "unsupported optional features (%x)",
2311                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2312                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2313                 return 0;
2314         }
2315
2316         if (readonly)
2317                 return 1;
2318
2319         /* Check that feature set is OK for a read-write mount */
2320         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2321                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2322                          "unsupported optional features (%x)",
2323                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2324                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2325                 return 0;
2326         }
2327         /*
2328          * Large file size enabled file system can only be mounted
2329          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2330          */
2331         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2332                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2333                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2334                                  "cannot be mounted RDWR without "
2335                                  "CONFIG_LBDAF");
2336                         return 0;
2337                 }
2338         }
2339         return 1;
2340 }
2341
2342 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2343                                 __releases(kernel_lock)
2344                                 __acquires(kernel_lock)
2345 {
2346         struct buffer_head *bh;
2347         struct ext4_super_block *es = NULL;
2348         struct ext4_sb_info *sbi;
2349         ext4_fsblk_t block;
2350         ext4_fsblk_t sb_block = get_sb_block(&data);
2351         ext4_fsblk_t logical_sb_block;
2352         unsigned long offset = 0;
2353         unsigned long journal_devnum = 0;
2354         unsigned long def_mount_opts;
2355         struct inode *root;
2356         char *cp;
2357         const char *descr;
2358         int ret = -EINVAL;
2359         int blocksize;
2360         unsigned int db_count;
2361         unsigned int i;
2362         int needs_recovery, has_huge_files;
2363         __u64 blocks_count;
2364         int err;
2365         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2366
2367         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2368         if (!sbi)
2369                 return -ENOMEM;
2370
2371         sbi->s_blockgroup_lock =
2372                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2373         if (!sbi->s_blockgroup_lock) {
2374                 kfree(sbi);
2375                 return -ENOMEM;
2376         }
2377         sb->s_fs_info = sbi;
2378         sbi->s_mount_opt = 0;
2379         sbi->s_resuid = EXT4_DEF_RESUID;
2380         sbi->s_resgid = EXT4_DEF_RESGID;
2381         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2382         sbi->s_sb_block = sb_block;
2383         sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2384                                                       sectors[1]);
2385
2386         unlock_kernel();
2387
2388         /* Cleanup superblock name */
2389         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2390                 *cp = '!';
2391
2392         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2393         if (!blocksize) {
2394                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2395                 goto out_fail;
2396         }
2397
2398         /*
2399          * The ext4 superblock will not be buffer aligned for other than 1kB
2400          * block sizes.  We need to calculate the offset from buffer start.
2401          */
2402         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2403                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2404                 offset = do_div(logical_sb_block, blocksize);
2405         } else {
2406                 logical_sb_block = sb_block;
2407         }
2408
2409         if (!(bh = sb_bread(sb, logical_sb_block))) {
2410                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
2411                 goto out_fail;
2412         }
2413         /*
2414          * Note: s_es must be initialized as soon as possible because
2415          *       some ext4 macro-instructions depend on its value
2416          */
2417         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2418         sbi->s_es = es;
2419         sb->s_magic = le16_to_cpu(es->s_magic);
2420         if (sb->s_magic != EXT4_SUPER_MAGIC)
2421                 goto cantfind_ext4;
2422         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2423
2424         /* Set defaults before we parse the mount options */
2425         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2426         if (def_mount_opts & EXT4_DEFM_DEBUG)
2427                 set_opt(sbi->s_mount_opt, DEBUG);
2428         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
2429                 set_opt(sbi->s_mount_opt, GRPID);
2430         if (def_mount_opts & EXT4_DEFM_UID16)
2431                 set_opt(sbi->s_mount_opt, NO_UID32);
2432 #ifdef CONFIG_EXT4_FS_XATTR
2433         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2434                 set_opt(sbi->s_mount_opt, XATTR_USER);
2435 #endif
2436 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2437         if (def_mount_opts & EXT4_DEFM_ACL)
2438                 set_opt(sbi->s_mount_opt, POSIX_ACL);
2439 #endif
2440         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2441                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
2442         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2443                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
2444         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2445                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2446
2447         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2448                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2449         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2450                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2451         else
2452                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2453
2454         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2455         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2456         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2457         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2458         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2459
2460         set_opt(sbi->s_mount_opt, BARRIER);
2461
2462         /*
2463          * enable delayed allocation by default
2464          * Use -o nodelalloc to turn it off
2465          */
2466         set_opt(sbi->s_mount_opt, DELALLOC);
2467
2468         if (!parse_options((char *) data, sb, &journal_devnum,
2469                            &journal_ioprio, NULL, 0))
2470                 goto failed_mount;
2471
2472         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2473                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2474
2475         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2476             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2477              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2478              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2479                 ext4_msg(sb, KERN_WARNING,
2480                        "feature flags set on rev 0 fs, "
2481                        "running e2fsck is recommended");
2482
2483         /*
2484          * Check feature flags regardless of the revision level, since we
2485          * previously didn't change the revision level when setting the flags,
2486          * so there is a chance incompat flags are set on a rev 0 filesystem.
2487          */
2488         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
2489                 goto failed_mount;
2490
2491         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2492
2493         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2494             blocksize > EXT4_MAX_BLOCK_SIZE) {
2495                 ext4_msg(sb, KERN_ERR,
2496                        "Unsupported filesystem blocksize %d", blocksize);
2497                 goto failed_mount;
2498         }
2499
2500         if (sb->s_blocksize != blocksize) {
2501                 /* Validate the filesystem blocksize */
2502                 if (!sb_set_blocksize(sb, blocksize)) {
2503                         ext4_msg(sb, KERN_ERR, "bad block size %d",
2504                                         blocksize);
2505                         goto failed_mount;
2506                 }
2507
2508                 brelse(bh);
2509                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2510                 offset = do_div(logical_sb_block, blocksize);
2511                 bh = sb_bread(sb, logical_sb_block);
2512                 if (!bh) {
2513                         ext4_msg(sb, KERN_ERR,
2514                                "Can't read superblock on 2nd try");
2515                         goto failed_mount;
2516                 }
2517                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2518                 sbi->s_es = es;
2519                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2520                         ext4_msg(sb, KERN_ERR,
2521                                "Magic mismatch, very weird!");
2522                         goto failed_mount;
2523                 }
2524         }
2525
2526         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2527                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2528         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2529                                                       has_huge_files);
2530         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2531
2532         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2533                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2534                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2535         } else {
2536                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2537                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2538                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2539                     (!is_power_of_2(sbi->s_inode_size)) ||
2540                     (sbi->s_inode_size > blocksize)) {
2541                         ext4_msg(sb, KERN_ERR,
2542                                "unsupported inode size: %d",
2543                                sbi->s_inode_size);
2544                         goto failed_mount;
2545                 }
2546                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2547                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2548         }
2549
2550         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2551         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2552                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2553                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2554                     !is_power_of_2(sbi->s_desc_size)) {
2555                         ext4_msg(sb, KERN_ERR,
2556                                "unsupported descriptor size %lu",
2557                                sbi->s_desc_size);
2558                         goto failed_mount;
2559                 }
2560         } else
2561                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2562
2563         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2564         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2565         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2566                 goto cantfind_ext4;
2567
2568         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2569         if (sbi->s_inodes_per_block == 0)
2570                 goto cantfind_ext4;
2571         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2572                                         sbi->s_inodes_per_block;
2573         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2574         sbi->s_sbh = bh;
2575         sbi->s_mount_state = le16_to_cpu(es->s_state);
2576         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2577         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2578
2579         for (i = 0; i < 4; i++)
2580                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2581         sbi->s_def_hash_version = es->s_def_hash_version;
2582         i = le32_to_cpu(es->s_flags);
2583         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2584                 sbi->s_hash_unsigned = 3;
2585         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2586 #ifdef __CHAR_UNSIGNED__
2587                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2588                 sbi->s_hash_unsigned = 3;
2589 #else
2590                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2591 #endif
2592                 sb->s_dirt = 1;
2593         }
2594
2595         if (sbi->s_blocks_per_group > blocksize * 8) {
2596                 ext4_msg(sb, KERN_ERR,
2597                        "#blocks per group too big: %lu",
2598                        sbi->s_blocks_per_group);
2599                 goto failed_mount;
2600         }
2601         if (sbi->s_inodes_per_group > blocksize * 8) {
2602                 ext4_msg(sb, KERN_ERR,
2603                        "#inodes per group too big: %lu",
2604                        sbi->s_inodes_per_group);
2605                 goto failed_mount;
2606         }
2607
2608         /*
2609          * Test whether we have more sectors than will fit in sector_t,
2610          * and whether the max offset is addressable by the page cache.
2611          */
2612         if ((ext4_blocks_count(es) >
2613              (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) ||
2614             (ext4_blocks_count(es) >
2615              (pgoff_t)(~0ULL) >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits))) {
2616                 ext4_msg(sb, KERN_ERR, "filesystem"
2617                          " too large to mount safely on this system");
2618                 if (sizeof(sector_t) < 8)
2619                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
2620                 ret = -EFBIG;
2621                 goto failed_mount;
2622         }
2623
2624         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2625                 goto cantfind_ext4;
2626
2627         /* check blocks count against device size */
2628         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2629         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2630                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
2631                        "exceeds size of device (%llu blocks)",
2632                        ext4_blocks_count(es), blocks_count);
2633                 goto failed_mount;
2634         }
2635
2636         /*
2637          * It makes no sense for the first data block to be beyond the end
2638          * of the filesystem.
2639          */
2640         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2641                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
2642                          "block %u is beyond end of filesystem (%llu)",
2643                          le32_to_cpu(es->s_first_data_block),
2644                          ext4_blocks_count(es));
2645                 goto failed_mount;
2646         }
2647         blocks_count = (ext4_blocks_count(es) -
2648                         le32_to_cpu(es->s_first_data_block) +
2649                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2650         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2651         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2652                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
2653                        "(block count %llu, first data block %u, "
2654                        "blocks per group %lu)", sbi->s_groups_count,
2655                        ext4_blocks_count(es),
2656                        le32_to_cpu(es->s_first_data_block),
2657                        EXT4_BLOCKS_PER_GROUP(sb));
2658                 goto failed_mount;
2659         }
2660         sbi->s_groups_count = blocks_count;
2661         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
2662                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
2663         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2664                    EXT4_DESC_PER_BLOCK(sb);
2665         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2666                                     GFP_KERNEL);
2667         if (sbi->s_group_desc == NULL) {
2668                 ext4_msg(sb, KERN_ERR, "not enough memory");
2669                 goto failed_mount;
2670         }
2671
2672 #ifdef CONFIG_PROC_FS
2673         if (ext4_proc_root)
2674                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2675 #endif
2676
2677         bgl_lock_init(sbi->s_blockgroup_lock);
2678
2679         for (i = 0; i < db_count; i++) {
2680                 block = descriptor_loc(sb, logical_sb_block, i);
2681                 sbi->s_group_desc[i] = sb_bread(sb, block);
2682                 if (!sbi->s_group_desc[i]) {
2683                         ext4_msg(sb, KERN_ERR,
2684                                "can't read group descriptor %d", i);
2685                         db_count = i;
2686                         goto failed_mount2;
2687                 }
2688         }
2689         if (!ext4_check_descriptors(sb)) {
2690                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
2691                 goto failed_mount2;
2692         }
2693         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2694                 if (!ext4_fill_flex_info(sb)) {
2695                         ext4_msg(sb, KERN_ERR,
2696                                "unable to initialize "
2697                                "flex_bg meta info!");
2698                         goto failed_mount2;
2699                 }
2700
2701         sbi->s_gdb_count = db_count;
2702         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2703         spin_lock_init(&sbi->s_next_gen_lock);
2704
2705         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2706                         ext4_count_free_blocks(sb));
2707         if (!err) {
2708                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2709                                 ext4_count_free_inodes(sb));
2710         }
2711         if (!err) {
2712                 err = percpu_counter_init(&sbi->s_dirs_counter,
2713                                 ext4_count_dirs(sb));
2714         }
2715         if (!err) {
2716                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2717         }
2718         if (err) {
2719                 ext4_msg(sb, KERN_ERR, "insufficient memory");
2720                 goto failed_mount3;
2721         }
2722
2723         sbi->s_stripe = ext4_get_stripe_size(sbi);
2724         sbi->s_max_writeback_mb_bump = 128;
2725
2726         /*
2727          * set up enough so that it can read an inode
2728          */
2729         if (!test_opt(sb, NOLOAD) &&
2730             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2731                 sb->s_op = &ext4_sops;
2732         else
2733                 sb->s_op = &ext4_nojournal_sops;
2734         sb->s_export_op = &ext4_export_ops;
2735         sb->s_xattr = ext4_xattr_handlers;
2736 #ifdef CONFIG_QUOTA
2737         sb->s_qcop = &ext4_qctl_operations;
2738         sb->dq_op = &ext4_quota_operations;
2739 #endif
2740         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2741         mutex_init(&sbi->s_orphan_lock);
2742         mutex_init(&sbi->s_resize_lock);
2743
2744         sb->s_root = NULL;
2745
2746         needs_recovery = (es->s_last_orphan != 0 ||
2747                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2748                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2749
2750         /*
2751          * The first inode we look at is the journal inode.  Don't try
2752          * root first: it may be modified in the journal!
2753          */
2754         if (!test_opt(sb, NOLOAD) &&
2755             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2756                 if (ext4_load_journal(sb, es, journal_devnum))
2757                         goto failed_mount3;
2758         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2759               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2760                 ext4_msg(sb, KERN_ERR, "required journal recovery "
2761                        "suppressed and not mounted read-only");
2762                 goto failed_mount4;
2763         } else {
2764                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2765                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2766                 sbi->s_journal = NULL;
2767                 needs_recovery = 0;
2768                 goto no_journal;
2769         }
2770
2771         if (ext4_blocks_count(es) > 0xffffffffULL &&
2772             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2773                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2774                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
2775                 goto failed_mount4;
2776         }
2777
2778         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2779                 jbd2_journal_set_features(sbi->s_journal,
2780                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2781                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2782         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2783                 jbd2_journal_set_features(sbi->s_journal,
2784                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2785                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2786                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2787         } else {
2788                 jbd2_journal_clear_features(sbi->s_journal,
2789                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2790                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2791         }
2792
2793         /* We have now updated the journal if required, so we can
2794          * validate the data journaling mode. */
2795         switch (test_opt(sb, DATA_FLAGS)) {
2796         case 0:
2797                 /* No mode set, assume a default based on the journal
2798                  * capabilities: ORDERED_DATA if the journal can
2799                  * cope, else JOURNAL_DATA
2800                  */
2801                 if (jbd2_journal_check_available_features
2802                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2803                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2804                 else
2805                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2806                 break;
2807
2808         case EXT4_MOUNT_ORDERED_DATA:
2809         case EXT4_MOUNT_WRITEBACK_DATA:
2810                 if (!jbd2_journal_check_available_features
2811                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2812                         ext4_msg(sb, KERN_ERR, "Journal does not support "
2813                                "requested data journaling mode");
2814                         goto failed_mount4;
2815                 }
2816         default:
2817                 break;
2818         }
2819         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
2820
2821 no_journal:
2822
2823         if (test_opt(sb, NOBH)) {
2824                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2825                         ext4_msg(sb, KERN_WARNING, "Ignoring nobh option - "
2826                                 "its supported only with writeback mode");
2827                         clear_opt(sbi->s_mount_opt, NOBH);
2828                 }
2829         }
2830         EXT4_SB(sb)->dio_unwritten_wq = create_workqueue("ext4-dio-unwritten");
2831         if (!EXT4_SB(sb)->dio_unwritten_wq) {
2832                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
2833                 goto failed_mount_wq;
2834         }
2835
2836         /*
2837          * The jbd2_journal_load will have done any necessary log recovery,
2838          * so we can safely mount the rest of the filesystem now.
2839          */
2840
2841         root = ext4_iget(sb, EXT4_ROOT_INO);
2842         if (IS_ERR(root)) {
2843                 ext4_msg(sb, KERN_ERR, "get root inode failed");
2844                 ret = PTR_ERR(root);
2845                 goto failed_mount4;
2846         }
2847         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2848                 iput(root);
2849                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
2850                 goto failed_mount4;
2851         }
2852         sb->s_root = d_alloc_root(root);
2853         if (!sb->s_root) {
2854                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
2855                 iput(root);
2856                 ret = -ENOMEM;
2857                 goto failed_mount4;
2858         }
2859
2860         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2861
2862         /* determine the minimum size of new large inodes, if present */
2863         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2864                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2865                                                      EXT4_GOOD_OLD_INODE_SIZE;
2866                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2867                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2868                         if (sbi->s_want_extra_isize <
2869                             le16_to_cpu(es->s_want_extra_isize))
2870                                 sbi->s_want_extra_isize =
2871                                         le16_to_cpu(es->s_want_extra_isize);
2872                         if (sbi->s_want_extra_isize <
2873                             le16_to_cpu(es->s_min_extra_isize))
2874                                 sbi->s_want_extra_isize =
2875                                         le16_to_cpu(es->s_min_extra_isize);
2876                 }
2877         }
2878         /* Check if enough inode space is available */
2879         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2880                                                         sbi->s_inode_size) {
2881                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2882                                                        EXT4_GOOD_OLD_INODE_SIZE;
2883                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
2884                          "available");
2885         }
2886
2887         if (test_opt(sb, DELALLOC) &&
2888             (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2889                 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
2890                          "requested data journaling mode");
2891                 clear_opt(sbi->s_mount_opt, DELALLOC);
2892         }
2893
2894         err = ext4_setup_system_zone(sb);
2895         if (err) {
2896                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
2897                          "zone (%d)\n", err);
2898                 goto failed_mount4;
2899         }
2900
2901         ext4_ext_init(sb);
2902         err = ext4_mb_init(sb, needs_recovery);
2903         if (err) {
2904                 ext4_msg(sb, KERN_ERR, "failed to initalize mballoc (%d)",
2905                          err);
2906                 goto failed_mount4;
2907         }
2908
2909         sbi->s_kobj.kset = ext4_kset;
2910         init_completion(&sbi->s_kobj_unregister);
2911         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
2912                                    "%s", sb->s_id);
2913         if (err) {
2914                 ext4_mb_release(sb);
2915                 ext4_ext_release(sb);
2916                 goto failed_mount4;
2917         };
2918
2919         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2920         ext4_orphan_cleanup(sb, es);
2921         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2922         if (needs_recovery) {
2923                 ext4_msg(sb, KERN_INFO, "recovery complete");
2924                 ext4_mark_recovery_complete(sb, es);
2925         }
2926         if (EXT4_SB(sb)->s_journal) {
2927                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2928                         descr = " journalled data mode";
2929                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2930                         descr = " ordered data mode";
2931                 else
2932                         descr = " writeback data mode";
2933         } else
2934                 descr = "out journal";
2935
2936         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s", descr);
2937
2938         lock_kernel();
2939         return 0;
2940
2941 cantfind_ext4:
2942         if (!silent)
2943                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
2944         goto failed_mount;
2945
2946 failed_mount4:
2947         ext4_msg(sb, KERN_ERR, "mount failed");
2948         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
2949 failed_mount_wq:
2950         ext4_release_system_zone(sb);
2951         if (sbi->s_journal) {
2952                 jbd2_journal_destroy(sbi->s_journal);
2953                 sbi->s_journal = NULL;
2954         }
2955 failed_mount3:
2956         if (sbi->s_flex_groups) {
2957                 if (is_vmalloc_addr(sbi->s_flex_groups))
2958                         vfree(sbi->s_flex_groups);
2959                 else
2960                         kfree(sbi->s_flex_groups);
2961         }
2962         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2963         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2964         percpu_counter_destroy(&sbi->s_dirs_counter);
2965         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2966 failed_mount2:
2967         for (i = 0; i < db_count; i++)
2968                 brelse(sbi->s_group_desc[i]);
2969         kfree(sbi->s_group_desc);
2970 failed_mount:
2971         if (sbi->s_proc) {
2972                 remove_proc_entry(sb->s_id, ext4_proc_root);
2973         }
2974 #ifdef CONFIG_QUOTA
2975         for (i = 0; i < MAXQUOTAS; i++)
2976                 kfree(sbi->s_qf_names[i]);
2977 #endif
2978         ext4_blkdev_remove(sbi);
2979         brelse(bh);
2980 out_fail:
2981         sb->s_fs_info = NULL;
2982         kfree(sbi->s_blockgroup_lock);
2983         kfree(sbi);
2984         lock_kernel();
2985         return ret;
2986 }
2987
2988 /*
2989  * Setup any per-fs journal parameters now.  We'll do this both on
2990  * initial mount, once the journal has been initialised but before we've
2991  * done any recovery; and again on any subsequent remount.
2992  */
2993 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2994 {
2995         struct ext4_sb_info *sbi = EXT4_SB(sb);
2996
2997         journal->j_commit_interval = sbi->s_commit_interval;
2998         journal->j_min_batch_time = sbi->s_min_batch_time;
2999         journal->j_max_batch_time = sbi->s_max_batch_time;
3000
3001         spin_lock(&journal->j_state_lock);
3002         if (test_opt(sb, BARRIER))
3003                 journal->j_flags |= JBD2_BARRIER;
3004         else
3005                 journal->j_flags &= ~JBD2_BARRIER;
3006         if (test_opt(sb, DATA_ERR_ABORT))
3007                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3008         else
3009                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3010         spin_unlock(&journal->j_state_lock);
3011 }
3012
3013 static journal_t *ext4_get_journal(struct super_block *sb,
3014                                    unsigned int journal_inum)
3015 {
3016         struct inode *journal_inode;
3017         journal_t *journal;
3018
3019         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3020
3021         /* First, test for the existence of a valid inode on disk.  Bad
3022          * things happen if we iget() an unused inode, as the subsequent
3023          * iput() will try to delete it. */
3024
3025         journal_inode = ext4_iget(sb, journal_inum);
3026         if (IS_ERR(journal_inode)) {
3027                 ext4_msg(sb, KERN_ERR, "no journal found");
3028                 return NULL;
3029         }
3030         if (!journal_inode->i_nlink) {
3031                 make_bad_inode(journal_inode);
3032                 iput(journal_inode);
3033                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3034                 return NULL;
3035         }
3036
3037         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3038                   journal_inode, journal_inode->i_size);
3039         if (!S_ISREG(journal_inode->i_mode)) {
3040                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3041                 iput(journal_inode);
3042                 return NULL;
3043         }
3044
3045         journal = jbd2_journal_init_inode(journal_inode);
3046         if (!journal) {
3047                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3048                 iput(journal_inode);
3049                 return NULL;
3050         }
3051         journal->j_private = sb;
3052         ext4_init_journal_params(sb, journal);
3053         return journal;
3054 }
3055
3056 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3057                                        dev_t j_dev)
3058 {
3059         struct buffer_head *bh;
3060         journal_t *journal;
3061         ext4_fsblk_t start;
3062         ext4_fsblk_t len;
3063         int hblock, blocksize;
3064         ext4_fsblk_t sb_block;
3065         unsigned long offset;
3066         struct ext4_super_block *es;
3067         struct block_device *bdev;
3068
3069         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3070
3071         bdev = ext4_blkdev_get(j_dev, sb);
3072         if (bdev == NULL)
3073                 return NULL;
3074
3075         if (bd_claim(bdev, sb)) {
3076                 ext4_msg(sb, KERN_ERR,
3077                         "failed to claim external journal device");
3078                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3079                 return NULL;
3080         }
3081
3082         blocksize = sb->s_blocksize;
3083         hblock = bdev_logical_block_size(bdev);
3084         if (blocksize < hblock) {
3085                 ext4_msg(sb, KERN_ERR,
3086                         "blocksize too small for journal device");
3087                 goto out_bdev;
3088         }
3089
3090         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3091         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3092         set_blocksize(bdev, blocksize);
3093         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3094                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3095                        "external journal");
3096                 goto out_bdev;
3097         }
3098
3099         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3100         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3101             !(le32_to_cpu(es->s_feature_incompat) &
3102               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3103                 ext4_msg(sb, KERN_ERR, "external journal has "
3104                                         "bad superblock");
3105                 brelse(bh);
3106                 goto out_bdev;
3107         }
3108
3109         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3110                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3111                 brelse(bh);
3112                 goto out_bdev;
3113         }
3114
3115         len = ext4_blocks_count(es);
3116         start = sb_block + 1;
3117         brelse(bh);     /* we're done with the superblock */
3118
3119         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3120                                         start, len, blocksize);
3121         if (!journal) {
3122                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3123                 goto out_bdev;
3124         }
3125         journal->j_private = sb;
3126         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3127         wait_on_buffer(journal->j_sb_buffer);
3128         if (!buffer_uptodate(journal->j_sb_buffer)) {
3129                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3130                 goto out_journal;
3131         }
3132         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3133                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3134                                         "user (unsupported) - %d",
3135                         be32_to_cpu(journal->j_superblock->s_nr_users));
3136                 goto out_journal;
3137         }
3138         EXT4_SB(sb)->journal_bdev = bdev;
3139         ext4_init_journal_params(sb, journal);
3140         return journal;
3141
3142 out_journal:
3143         jbd2_journal_destroy(journal);
3144 out_bdev:
3145         ext4_blkdev_put(bdev);
3146         return NULL;
3147 }
3148
3149 static int ext4_load_journal(struct super_block *sb,
3150                              struct ext4_super_block *es,
3151                              unsigned long journal_devnum)
3152 {
3153         journal_t *journal;
3154         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3155         dev_t journal_dev;
3156         int err = 0;
3157         int really_read_only;
3158
3159         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3160
3161         if (journal_devnum &&
3162             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3163                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3164                         "numbers have changed");
3165                 journal_dev = new_decode_dev(journal_devnum);
3166         } else
3167                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3168
3169         really_read_only = bdev_read_only(sb->s_bdev);
3170
3171         /*
3172          * Are we loading a blank journal or performing recovery after a
3173          * crash?  For recovery, we need to check in advance whether we
3174          * can get read-write access to the device.
3175          */
3176         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3177                 if (sb->s_flags & MS_RDONLY) {
3178                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3179                                         "required on readonly filesystem");
3180                         if (really_read_only) {
3181                                 ext4_msg(sb, KERN_ERR, "write access "
3182                                         "unavailable, cannot proceed");
3183                                 return -EROFS;
3184                         }
3185                         ext4_msg(sb, KERN_INFO, "write access will "
3186                                "be enabled during recovery");
3187                 }
3188         }
3189
3190         if (journal_inum && journal_dev) {
3191                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3192                        "and inode journals!");
3193                 return -EINVAL;
3194         }
3195
3196         if (journal_inum) {
3197                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3198                         return -EINVAL;
3199         } else {
3200                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3201                         return -EINVAL;
3202         }
3203
3204         if (!(journal->j_flags & JBD2_BARRIER))
3205                 ext4_msg(sb, KERN_INFO, "barriers disabled");
3206
3207         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3208                 err = jbd2_journal_update_format(journal);
3209                 if (err)  {
3210                         ext4_msg(sb, KERN_ERR, "error updating journal");
3211                         jbd2_journal_destroy(journal);
3212                         return err;
3213                 }
3214         }
3215
3216         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3217                 err = jbd2_journal_wipe(journal, !really_read_only);
3218         if (!err)
3219                 err = jbd2_journal_load(journal);
3220
3221         if (err) {
3222                 ext4_msg(sb, KERN_ERR, "error loading journal");
3223                 jbd2_journal_destroy(journal);
3224                 return err;
3225         }
3226
3227         EXT4_SB(sb)->s_journal = journal;
3228         ext4_clear_journal_err(sb, es);
3229
3230         if (journal_devnum &&
3231             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3232                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3233
3234                 /* Make sure we flush the recovery flag to disk. */
3235                 ext4_commit_super(sb, 1);
3236         }
3237
3238         return 0;
3239 }
3240
3241 static int ext4_commit_super(struct super_block *sb, int sync)
3242 {
3243         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3244         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3245         int error = 0;
3246
3247         if (!sbh)
3248                 return error;
3249         if (buffer_write_io_error(sbh)) {
3250                 /*
3251                  * Oh, dear.  A previous attempt to write the
3252                  * superblock failed.  This could happen because the
3253                  * USB device was yanked out.  Or it could happen to
3254                  * be a transient write error and maybe the block will
3255                  * be remapped.  Nothing we can do but to retry the
3256                  * write and hope for the best.
3257                  */
3258                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
3259                        "superblock detected");
3260                 clear_buffer_write_io_error(sbh);
3261                 set_buffer_uptodate(sbh);
3262         }
3263         /*
3264          * If the file system is mounted read-only, don't update the
3265          * superblock write time.  This avoids updating the superblock
3266          * write time when we are mounting the root file system
3267          * read/only but we need to replay the journal; at that point,
3268          * for people who are east of GMT and who make their clock
3269          * tick in localtime for Windows bug-for-bug compatibility,
3270          * the clock is set in the future, and this will cause e2fsck
3271          * to complain and force a full file system check.
3272          */
3273         if (!(sb->s_flags & MS_RDONLY))
3274                 es->s_wtime = cpu_to_le32(get_seconds());
3275         es->s_kbytes_written =
3276                 cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
3277                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
3278                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
3279         ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
3280                                         &EXT4_SB(sb)->s_freeblocks_counter));
3281         es->s_free_inodes_count = cpu_to_le32(percpu_counter_sum_positive(
3282                                         &EXT4_SB(sb)->s_freeinodes_counter));
3283         sb->s_dirt = 0;
3284         BUFFER_TRACE(sbh, "marking dirty");
3285         mark_buffer_dirty(sbh);
3286         if (sync) {
3287                 error = sync_dirty_buffer(sbh);
3288                 if (error)
3289                         return error;
3290
3291                 error = buffer_write_io_error(sbh);
3292                 if (error) {
3293                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
3294                                "superblock");
3295                         clear_buffer_write_io_error(sbh);
3296                         set_buffer_uptodate(sbh);
3297                 }
3298         }
3299         return error;
3300 }
3301
3302 /*
3303  * Have we just finished recovery?  If so, and if we are mounting (or
3304  * remounting) the filesystem readonly, then we will end up with a
3305  * consistent fs on disk.  Record that fact.
3306  */
3307 static void ext4_mark_recovery_complete(struct super_block *sb,
3308                                         struct ext4_super_block *es)
3309 {
3310         journal_t *journal = EXT4_SB(sb)->s_journal;
3311
3312         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3313                 BUG_ON(journal != NULL);
3314                 return;
3315         }
3316         jbd2_journal_lock_updates(journal);
3317         if (jbd2_journal_flush(journal) < 0)
3318                 goto out;
3319
3320         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
3321             sb->s_flags & MS_RDONLY) {
3322                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3323                 ext4_commit_super(sb, 1);
3324         }
3325
3326 out:
3327         jbd2_journal_unlock_updates(journal);
3328 }
3329
3330 /*
3331  * If we are mounting (or read-write remounting) a filesystem whose journal
3332  * has recorded an error from a previous lifetime, move that error to the
3333  * main filesystem now.
3334  */
3335 static void ext4_clear_journal_err(struct super_block *sb,
3336                                    struct ext4_super_block *es)
3337 {
3338         journal_t *journal;
3339         int j_errno;
3340         const char *errstr;
3341
3342         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3343
3344         journal = EXT4_SB(sb)->s_journal;
3345
3346         /*
3347          * Now check for any error status which may have been recorded in the
3348          * journal by a prior ext4_error() or ext4_abort()
3349          */
3350
3351         j_errno = jbd2_journal_errno(journal);
3352         if (j_errno) {
3353                 char nbuf[16];
3354
3355                 errstr = ext4_decode_error(sb, j_errno, nbuf);
3356                 ext4_warning(sb, __func__, "Filesystem error recorded "
3357                              "from previous mount: %s", errstr);
3358                 ext4_warning(sb, __func__, "Marking fs in need of "
3359                              "filesystem check.");
3360
3361                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
3362                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
3363                 ext4_commit_super(sb, 1);
3364
3365                 jbd2_journal_clear_err(journal);
3366         }
3367 }
3368
3369 /*
3370  * Force the running and committing transactions to commit,
3371  * and wait on the commit.
3372  */
3373 int ext4_force_commit(struct super_block *sb)
3374 {
3375         journal_t *journal;
3376         int ret = 0;
3377
3378         if (sb->s_flags & MS_RDONLY)
3379                 return 0;
3380
3381         journal = EXT4_SB(sb)->s_journal;
3382         if (journal)
3383                 ret = ext4_journal_force_commit(journal);
3384
3385         return ret;
3386 }
3387
3388 static void ext4_write_super(struct super_block *sb)
3389 {
3390         lock_super(sb);
3391         ext4_commit_super(sb, 1);
3392         unlock_super(sb);
3393 }
3394
3395 static int ext4_sync_fs(struct super_block *sb, int wait)
3396 {
3397         int ret = 0;
3398         tid_t target;
3399         struct ext4_sb_info *sbi = EXT4_SB(sb);
3400
3401         trace_ext4_sync_fs(sb, wait);
3402         flush_workqueue(sbi->dio_unwritten_wq);
3403         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
3404                 if (wait)
3405                         jbd2_log_wait_commit(sbi->s_journal, target);
3406         }
3407         return ret;
3408 }
3409
3410 /*
3411  * LVM calls this function before a (read-only) snapshot is created.  This
3412  * gives us a chance to flush the journal completely and mark the fs clean.
3413  */
3414 static int ext4_freeze(struct super_block *sb)
3415 {
3416         int error = 0;
3417         journal_t *journal;
3418
3419         if (sb->s_flags & MS_RDONLY)
3420                 return 0;
3421
3422         journal = EXT4_SB(sb)->s_journal;
3423
3424         /* Now we set up the journal barrier. */
3425         jbd2_journal_lock_updates(journal);
3426
3427         /*
3428          * Don't clear the needs_recovery flag if we failed to flush
3429          * the journal.
3430          */
3431         error = jbd2_journal_flush(journal);
3432         if (error < 0) {
3433         out:
3434                 jbd2_journal_unlock_updates(journal);
3435                 return error;
3436         }
3437
3438         /* Journal blocked and flushed, clear needs_recovery flag. */
3439         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3440         error = ext4_commit_super(sb, 1);
3441         if (error)
3442                 goto out;
3443         return 0;
3444 }
3445
3446 /*
3447  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
3448  * flag here, even though the filesystem is not technically dirty yet.
3449  */
3450 static int ext4_unfreeze(struct super_block *sb)
3451 {
3452         if (sb->s_flags & MS_RDONLY)
3453                 return 0;
3454
3455         lock_super(sb);
3456         /* Reset the needs_recovery flag before the fs is unlocked. */
3457         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3458         ext4_commit_super(sb, 1);
3459         unlock_super(sb);
3460         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3461         return 0;
3462 }
3463
3464 static int ext4_remount(struct super_block *sb, int *flags, char *data)
3465 {
3466         struct ext4_super_block *es;
3467         struct ext4_sb_info *sbi = EXT4_SB(sb);
3468         ext4_fsblk_t n_blocks_count = 0;
3469         unsigned long old_sb_flags;
3470         struct ext4_mount_options old_opts;
3471         ext4_group_t g;
3472         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3473         int err;
3474 #ifdef CONFIG_QUOTA
3475         int i;
3476 #endif
3477
3478         lock_kernel();
3479
3480         /* Store the original options */
3481         lock_super(sb);
3482         old_sb_flags = sb->s_flags;
3483         old_opts.s_mount_opt = sbi->s_mount_opt;
3484         old_opts.s_resuid = sbi->s_resuid;
3485         old_opts.s_resgid = sbi->s_resgid;
3486         old_opts.s_commit_interval = sbi->s_commit_interval;
3487         old_opts.s_min_batch_time = sbi->s_min_batch_time;
3488         old_opts.s_max_batch_time = sbi->s_max_batch_time;
3489 #ifdef CONFIG_QUOTA
3490         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
3491         for (i = 0; i < MAXQUOTAS; i++)
3492                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
3493 #endif
3494         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
3495                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
3496
3497         /*
3498          * Allow the "check" option to be passed as a remount option.
3499          */
3500         if (!parse_options(data, sb, NULL, &journal_ioprio,
3501                            &n_blocks_count, 1)) {
3502                 err = -EINVAL;
3503                 goto restore_opts;
3504         }
3505
3506         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
3507                 ext4_abort(sb, __func__, "Abort forced by user");
3508
3509         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3510                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
3511
3512         es = sbi->s_es;
3513
3514         if (sbi->s_journal) {
3515                 ext4_init_journal_params(sb, sbi->s_journal);
3516                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3517         }
3518
3519         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3520                 n_blocks_count > ext4_blocks_count(es)) {
3521                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
3522                         err = -EROFS;
3523                         goto restore_opts;
3524                 }
3525
3526                 if (*flags & MS_RDONLY) {
3527                         /*
3528                          * First of all, the unconditional stuff we have to do
3529                          * to disable replay of the journal when we next remount
3530                          */
3531                         sb->s_flags |= MS_RDONLY;
3532
3533                         /*
3534                          * OK, test if we are remounting a valid rw partition
3535                          * readonly, and if so set the rdonly flag and then
3536                          * mark the partition as valid again.
3537                          */
3538                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3539                             (sbi->s_mount_state & EXT4_VALID_FS))
3540                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3541
3542                         if (sbi->s_journal)
3543                                 ext4_mark_recovery_complete(sb, es);
3544                 } else {
3545                         /* Make sure we can mount this feature set readwrite */
3546                         if (!ext4_feature_set_ok(sb, 0)) {
3547                                 err = -EROFS;
3548                                 goto restore_opts;
3549                         }
3550                         /*
3551                          * Make sure the group descriptor checksums
3552                          * are sane.  If they aren't, refuse to remount r/w.
3553                          */
3554                         for (g = 0; g < sbi->s_groups_count; g++) {
3555                                 struct ext4_group_desc *gdp =
3556                                         ext4_get_group_desc(sb, g, NULL);
3557
3558                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3559                                         ext4_msg(sb, KERN_ERR,
3560                "ext4_remount: Checksum for group %u failed (%u!=%u)",
3561                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3562                                                le16_to_cpu(gdp->bg_checksum));
3563                                         err = -EINVAL;
3564                                         goto restore_opts;
3565                                 }
3566                         }
3567
3568                         /*
3569                          * If we have an unprocessed orphan list hanging
3570                          * around from a previously readonly bdev mount,
3571                          * require a full umount/remount for now.
3572                          */
3573                         if (es->s_last_orphan) {
3574                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
3575                                        "remount RDWR because of unprocessed "
3576                                        "orphan inode list.  Please "
3577                                        "umount/remount instead");
3578                                 err = -EINVAL;
3579                                 goto restore_opts;
3580                         }
3581
3582                         /*
3583                          * Mounting a RDONLY partition read-write, so reread
3584                          * and store the current valid flag.  (It may have
3585                          * been changed by e2fsck since we originally mounted
3586                          * the partition.)
3587                          */
3588                         if (sbi->s_journal)
3589                                 ext4_clear_journal_err(sb, es);
3590                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3591                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3592                                 goto restore_opts;
3593                         if (!ext4_setup_super(sb, es, 0))
3594                                 sb->s_flags &= ~MS_RDONLY;
3595                 }
3596         }
3597         ext4_setup_system_zone(sb);
3598         if (sbi->s_journal == NULL)
3599                 ext4_commit_super(sb, 1);
3600
3601 #ifdef CONFIG_QUOTA
3602         /* Release old quota file names */
3603         for (i = 0; i < MAXQUOTAS; i++)
3604                 if (old_opts.s_qf_names[i] &&
3605                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3606                         kfree(old_opts.s_qf_names[i]);
3607 #endif
3608         unlock_super(sb);
3609         unlock_kernel();
3610         return 0;
3611
3612 restore_opts:
3613         sb->s_flags = old_sb_flags;
3614         sbi->s_mount_opt = old_opts.s_mount_opt;
3615         sbi->s_resuid = old_opts.s_resuid;
3616         sbi->s_resgid = old_opts.s_resgid;
3617         sbi->s_commit_interval = old_opts.s_commit_interval;
3618         sbi->s_min_batch_time = old_opts.s_min_batch_time;
3619         sbi->s_max_batch_time = old_opts.s_max_batch_time;
3620 #ifdef CONFIG_QUOTA
3621         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3622         for (i = 0; i < MAXQUOTAS; i++) {
3623                 if (sbi->s_qf_names[i] &&
3624                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3625                         kfree(sbi->s_qf_names[i]);
3626                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3627         }
3628 #endif
3629         unlock_super(sb);
3630         unlock_kernel();
3631         return err;
3632 }
3633
3634 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3635 {
3636         struct super_block *sb = dentry->d_sb;
3637         struct ext4_sb_info *sbi = EXT4_SB(sb);
3638         struct ext4_super_block *es = sbi->s_es;
3639         u64 fsid;
3640
3641         if (test_opt(sb, MINIX_DF)) {
3642                 sbi->s_overhead_last = 0;
3643         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3644                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3645                 ext4_fsblk_t overhead = 0;
3646
3647                 /*
3648                  * Compute the overhead (FS structures).  This is constant
3649                  * for a given filesystem unless the number of block groups
3650                  * changes so we cache the previous value until it does.
3651                  */
3652
3653                 /*
3654                  * All of the blocks before first_data_block are
3655                  * overhead
3656                  */
3657                 overhead = le32_to_cpu(es->s_first_data_block);
3658
3659                 /*
3660                  * Add the overhead attributed to the superblock and
3661                  * block group descriptors.  If the sparse superblocks
3662                  * feature is turned on, then not all groups have this.
3663                  */
3664                 for (i = 0; i < ngroups; i++) {
3665                         overhead += ext4_bg_has_super(sb, i) +
3666                                 ext4_bg_num_gdb(sb, i);
3667                         cond_resched();
3668                 }
3669
3670                 /*
3671                  * Every block group has an inode bitmap, a block
3672                  * bitmap, and an inode table.
3673                  */
3674                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3675                 sbi->s_overhead_last = overhead;
3676                 smp_wmb();
3677                 sbi->s_blocks_last = ext4_blocks_count(es);
3678         }
3679
3680         buf->f_type = EXT4_SUPER_MAGIC;
3681         buf->f_bsize = sb->s_blocksize;
3682         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3683         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3684                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3685         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3686         if (buf->f_bfree < ext4_r_blocks_count(es))
3687                 buf->f_bavail = 0;
3688         buf->f_files = le32_to_cpu(es->s_inodes_count);
3689         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3690         buf->f_namelen = EXT4_NAME_LEN;
3691         fsid = le64_to_cpup((void *)es->s_uuid) ^
3692                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3693         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3694         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3695
3696         return 0;
3697 }
3698
3699 /* Helper function for writing quotas on sync - we need to start transaction
3700  * before quota file is locked for write. Otherwise the are possible deadlocks:
3701  * Process 1                         Process 2
3702  * ext4_create()                     quota_sync()
3703  *   jbd2_journal_start()                  write_dquot()
3704  *   vfs_dq_init()                         down(dqio_mutex)
3705  *     down(dqio_mutex)                    jbd2_journal_start()
3706  *
3707  */
3708
3709 #ifdef CONFIG_QUOTA
3710
3711 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3712 {
3713         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3714 }
3715
3716 static int ext4_write_dquot(struct dquot *dquot)
3717 {
3718         int ret, err;
3719         handle_t *handle;
3720         struct inode *inode;
3721
3722         inode = dquot_to_inode(dquot);
3723         handle = ext4_journal_start(inode,
3724                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3725         if (IS_ERR(handle))
3726                 return PTR_ERR(handle);
3727         ret = dquot_commit(dquot);
3728         err = ext4_journal_stop(handle);
3729         if (!ret)
3730                 ret = err;
3731         return ret;
3732 }
3733
3734 static int ext4_acquire_dquot(struct dquot *dquot)
3735 {
3736         int ret, err;
3737         handle_t *handle;
3738
3739         handle = ext4_journal_start(dquot_to_inode(dquot),
3740                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3741         if (IS_ERR(handle))
3742                 return PTR_ERR(handle);
3743         ret = dquot_acquire(dquot);
3744         err = ext4_journal_stop(handle);
3745         if (!ret)
3746                 ret = err;
3747         return ret;
3748 }
3749
3750 static int ext4_release_dquot(struct dquot *dquot)
3751 {
3752         int ret, err;
3753         handle_t *handle;
3754
3755         handle = ext4_journal_start(dquot_to_inode(dquot),
3756                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3757         if (IS_ERR(handle)) {
3758                 /* Release dquot anyway to avoid endless cycle in dqput() */
3759                 dquot_release(dquot);
3760                 return PTR_ERR(handle);
3761         }
3762         ret = dquot_release(dquot);
3763         err = ext4_journal_stop(handle);
3764         if (!ret)
3765                 ret = err;
3766         return ret;
3767 }
3768
3769 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3770 {
3771         /* Are we journaling quotas? */
3772         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3773             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3774                 dquot_mark_dquot_dirty(dquot);
3775                 return ext4_write_dquot(dquot);
3776         } else {
3777                 return dquot_mark_dquot_dirty(dquot);
3778         }
3779 }
3780
3781 static int ext4_write_info(struct super_block *sb, int type)
3782 {
3783         int ret, err;
3784         handle_t *handle;
3785
3786         /* Data block + inode block */
3787         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3788         if (IS_ERR(handle))
3789                 return PTR_ERR(handle);
3790         ret = dquot_commit_info(sb, type);
3791         err = ext4_journal_stop(handle);
3792         if (!ret)
3793                 ret = err;
3794         return ret;
3795 }
3796
3797 /*
3798  * Turn on quotas during mount time - we need to find
3799  * the quota file and such...
3800  */
3801 static int ext4_quota_on_mount(struct super_block *sb, int type)
3802 {
3803         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3804                                   EXT4_SB(sb)->s_jquota_fmt, type);
3805 }
3806
3807 /*
3808  * Standard function to be called on quota_on
3809  */
3810 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3811                          char *name, int remount)
3812 {
3813         int err;
3814         struct path path;
3815
3816         if (!test_opt(sb, QUOTA))
3817                 return -EINVAL;
3818         /* When remounting, no checks are needed and in fact, name is NULL */
3819         if (remount)
3820                 return vfs_quota_on(sb, type, format_id, name, remount);
3821
3822         err = kern_path(name, LOOKUP_FOLLOW, &path);
3823         if (err)
3824                 return err;
3825
3826         /* Quotafile not on the same filesystem? */
3827         if (path.mnt->mnt_sb != sb) {
3828                 path_put(&path);
3829                 return -EXDEV;
3830         }
3831         /* Journaling quota? */
3832         if (EXT4_SB(sb)->s_qf_names[type]) {
3833                 /* Quotafile not in fs root? */
3834                 if (path.dentry->d_parent != sb->s_root)
3835                         ext4_msg(sb, KERN_WARNING,
3836                                 "Quota file not on filesystem root. "
3837                                 "Journaled quota will not work");
3838         }
3839
3840         /*
3841          * When we journal data on quota file, we have to flush journal to see
3842          * all updates to the file when we bypass pagecache...
3843          */
3844         if (EXT4_SB(sb)->s_journal &&
3845             ext4_should_journal_data(path.dentry->d_inode)) {
3846                 /*
3847                  * We don't need to lock updates but journal_flush() could
3848                  * otherwise be livelocked...
3849                  */
3850                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3851                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3852                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3853                 if (err) {
3854                         path_put(&path);
3855                         return err;
3856                 }
3857         }
3858
3859         err = vfs_quota_on_path(sb, type, format_id, &path);
3860         path_put(&path);
3861         return err;
3862 }
3863
3864 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3865  * acquiring the locks... As quota files are never truncated and quota code
3866  * itself serializes the operations (and noone else should touch the files)
3867  * we don't have to be afraid of races */
3868 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3869                                size_t len, loff_t off)
3870 {
3871         struct inode *inode = sb_dqopt(sb)->files[type];
3872         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3873         int err = 0;
3874         int offset = off & (sb->s_blocksize - 1);
3875         int tocopy;
3876         size_t toread;
3877         struct buffer_head *bh;
3878         loff_t i_size = i_size_read(inode);
3879
3880         if (off > i_size)
3881                 return 0;
3882         if (off+len > i_size)
3883                 len = i_size-off;
3884         toread = len;
3885         while (toread > 0) {
3886                 tocopy = sb->s_blocksize - offset < toread ?
3887                                 sb->s_blocksize - offset : toread;
3888                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3889                 if (err)
3890                         return err;
3891                 if (!bh)        /* A hole? */
3892                         memset(data, 0, tocopy);
3893                 else
3894                         memcpy(data, bh->b_data+offset, tocopy);
3895                 brelse(bh);
3896                 offset = 0;
3897                 toread -= tocopy;
3898                 data += tocopy;
3899                 blk++;
3900         }
3901         return len;
3902 }
3903
3904 /* Write to quotafile (we know the transaction is already started and has
3905  * enough credits) */
3906 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3907                                 const char *data, size_t len, loff_t off)
3908 {
3909         struct inode *inode = sb_dqopt(sb)->files[type];
3910         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3911         int err = 0;
3912         int offset = off & (sb->s_blocksize - 1);
3913         int tocopy;
3914         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3915         size_t towrite = len;
3916         struct buffer_head *bh;
3917         handle_t *handle = journal_current_handle();
3918
3919         if (EXT4_SB(sb)->s_journal && !handle) {
3920                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
3921                         " cancelled because transaction is not started",
3922                         (unsigned long long)off, (unsigned long long)len);
3923                 return -EIO;
3924         }
3925         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3926         while (towrite > 0) {
3927                 tocopy = sb->s_blocksize - offset < towrite ?
3928                                 sb->s_blocksize - offset : towrite;
3929                 bh = ext4_bread(handle, inode, blk, 1, &err);
3930                 if (!bh)
3931                         goto out;
3932                 if (journal_quota) {
3933                         err = ext4_journal_get_write_access(handle, bh);
3934                         if (err) {
3935                                 brelse(bh);
3936                                 goto out;
3937                         }
3938                 }
3939                 lock_buffer(bh);
3940                 memcpy(bh->b_data+offset, data, tocopy);
3941                 flush_dcache_page(bh->b_page);
3942                 unlock_buffer(bh);
3943                 if (journal_quota)
3944                         err = ext4_handle_dirty_metadata(handle, NULL, bh);
3945                 else {
3946                         /* Always do at least ordered writes for quotas */
3947                         err = ext4_jbd2_file_inode(handle, inode);
3948                         mark_buffer_dirty(bh);
3949                 }
3950                 brelse(bh);
3951                 if (err)
3952                         goto out;
3953                 offset = 0;
3954                 towrite -= tocopy;
3955                 data += tocopy;
3956                 blk++;
3957         }
3958 out:
3959         if (len == towrite) {
3960                 mutex_unlock(&inode->i_mutex);
3961                 return err;
3962         }
3963         if (inode->i_size < off+len-towrite) {
3964                 i_size_write(inode, off+len-towrite);
3965                 EXT4_I(inode)->i_disksize = inode->i_size;
3966         }
3967         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3968         ext4_mark_inode_dirty(handle, inode);
3969         mutex_unlock(&inode->i_mutex);
3970         return len - towrite;
3971 }
3972
3973 #endif
3974
3975 static int ext4_get_sb(struct file_system_type *fs_type, int flags,
3976                        const char *dev_name, void *data, struct vfsmount *mnt)
3977 {
3978         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
3979 }
3980
3981 #if !defined(CONTIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
3982 static struct file_system_type ext2_fs_type = {
3983         .owner          = THIS_MODULE,
3984         .name           = "ext2",
3985         .get_sb         = ext4_get_sb,
3986         .kill_sb        = kill_block_super,
3987         .fs_flags       = FS_REQUIRES_DEV,
3988 };
3989
3990 static inline void register_as_ext2(void)
3991 {
3992         int err = register_filesystem(&ext2_fs_type);
3993         if (err)
3994                 printk(KERN_WARNING
3995                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
3996 }
3997
3998 static inline void unregister_as_ext2(void)
3999 {
4000         unregister_filesystem(&ext2_fs_type);
4001 }
4002 MODULE_ALIAS("ext2");
4003 #else
4004 static inline void register_as_ext2(void) { }
4005 static inline void unregister_as_ext2(void) { }
4006 #endif
4007
4008 #if !defined(CONTIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4009 static struct file_system_type ext3_fs_type = {
4010         .owner          = THIS_MODULE,
4011         .name           = "ext3",
4012         .get_sb         = ext4_get_sb,
4013         .kill_sb        = kill_block_super,
4014         .fs_flags       = FS_REQUIRES_DEV,
4015 };
4016
4017 static inline void register_as_ext3(void)
4018 {
4019         int err = register_filesystem(&ext3_fs_type);
4020         if (err)
4021                 printk(KERN_WARNING
4022                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
4023 }
4024
4025 static inline void unregister_as_ext3(void)
4026 {
4027         unregister_filesystem(&ext3_fs_type);
4028 }
4029 MODULE_ALIAS("ext3");
4030 #else
4031 static inline void register_as_ext3(void) { }
4032 static inline void unregister_as_ext3(void) { }
4033 #endif
4034
4035 static struct file_system_type ext4_fs_type = {
4036         .owner          = THIS_MODULE,
4037         .name           = "ext4",
4038         .get_sb         = ext4_get_sb,
4039         .kill_sb        = kill_block_super,
4040         .fs_flags       = FS_REQUIRES_DEV,
4041 };
4042
4043 static int __init init_ext4_fs(void)
4044 {
4045         int err;
4046
4047         err = init_ext4_system_zone();
4048         if (err)
4049                 return err;
4050         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
4051         if (!ext4_kset)
4052                 goto out4;
4053         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
4054         err = init_ext4_mballoc();
4055         if (err)
4056                 goto out3;
4057
4058         err = init_ext4_xattr();
4059         if (err)
4060                 goto out2;
4061         err = init_inodecache();
4062         if (err)
4063                 goto out1;
4064         register_as_ext2();
4065         register_as_ext3();
4066         err = register_filesystem(&ext4_fs_type);
4067         if (err)
4068                 goto out;
4069         return 0;
4070 out:
4071         unregister_as_ext2();
4072         unregister_as_ext3();
4073         destroy_inodecache();
4074 out1:
4075         exit_ext4_xattr();
4076 out2:
4077         exit_ext4_mballoc();
4078 out3:
4079         remove_proc_entry("fs/ext4", NULL);
4080         kset_unregister(ext4_kset);
4081 out4:
4082         exit_ext4_system_zone();
4083         return err;
4084 }
4085
4086 static void __exit exit_ext4_fs(void)
4087 {
4088         unregister_as_ext2();
4089         unregister_as_ext3();
4090         unregister_filesystem(&ext4_fs_type);
4091         destroy_inodecache();
4092         exit_ext4_xattr();
4093         exit_ext4_mballoc();
4094         remove_proc_entry("fs/ext4", NULL);
4095         kset_unregister(ext4_kset);
4096         exit_ext4_system_zone();
4097 }
4098
4099 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
4100 MODULE_DESCRIPTION("Fourth Extended Filesystem");
4101 MODULE_LICENSE("GPL");
4102 module_init(init_ext4_fs)
4103 module_exit(exit_ext4_fs)