fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/jbd2.h>
  24 #include <linux/slab.h>
  25 #include <linux/init.h>
  26 #include <linux/blkdev.h>
  27 #include <linux/parser.h>
  28 #include <linux/smp_lock.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/marker.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <asm/uaccess.h>
  42
  43 #include "ext4.h"
  44 #include "ext4_jbd2.h"
  45 #include "xattr.h"
  46 #include "acl.h"
  47 #include "namei.h"
  48 #include "group.h"
  49
  50 struct proc_dir_entry *ext4_proc_root;
  51
  52 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  53                              unsigned long journal_devnum);
  54 static int ext4_create_journal(struct super_block *, struct ext4_super_block *,
  55                                unsigned int);
  56 static void ext4_commit_super(struct super_block *sb,
  57                               struct ext4_super_block *es, int sync);
  58 static void ext4_mark_recovery_complete(struct super_block *sb,
  59                                         struct ext4_super_block *es);
  60 static void ext4_clear_journal_err(struct super_block *sb,
  61                                    struct ext4_super_block *es);
  62 static int ext4_sync_fs(struct super_block *sb, int wait);
  63 static const char *ext4_decode_error(struct super_block *sb, int errno,
  64                                      char nbuf[16]);
  65 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  66 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  67 static void ext4_unlockfs(struct super_block *sb);
  68 static void ext4_write_super(struct super_block *sb);
  69 static void ext4_write_super_lockfs(struct super_block *sb);
  70
  71
  72 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
  73                                struct ext4_group_desc *bg)
  74 {
  75         return le32_to_cpu(bg->bg_block_bitmap_lo) |
  76                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  77                 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
  78 }
  79
  80 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
  81                                struct ext4_group_desc *bg)
  82 {
  83         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
  84                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  85                 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
  86 }
  87
  88 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
  89                               struct ext4_group_desc *bg)
  90 {
  91         return le32_to_cpu(bg->bg_inode_table_lo) |
  92                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  93                 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
  94 }
  95
  96 void ext4_block_bitmap_set(struct super_block *sb,
  97                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
  98 {
  99         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 100         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 101                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 102 }
 103
 104 void ext4_inode_bitmap_set(struct super_block *sb,
 105                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 106 {
 107         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 108         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 109                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 110 }
 111
 112 void ext4_inode_table_set(struct super_block *sb,
 113                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 114 {
 115         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 116         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 117                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 118 }
 119
 120 /*
 121  * Wrappers for jbd2_journal_start/end.
 122  *
 123  * The only special thing we need to do here is to make sure that all
 124  * journal_end calls result in the superblock being marked dirty, so
 125  * that sync() will call the filesystem's write_super callback if
 126  * appropriate.
 127  */
 128 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 129 {
 130         journal_t *journal;
 131
 132         if (sb->s_flags & MS_RDONLY)
 133                 return ERR_PTR(-EROFS);
 134
 135         /* Special case here: if the journal has aborted behind our
 136          * backs (eg. EIO in the commit thread), then we still need to
 137          * take the FS itself readonly cleanly. */
 138         journal = EXT4_SB(sb)->s_journal;
 139         if (is_journal_aborted(journal)) {
 140                 ext4_abort(sb, __func__,
 141                            "Detected aborted journal");
 142                 return ERR_PTR(-EROFS);
 143         }
 144
 145         return jbd2_journal_start(journal, nblocks);
 146 }
 147
 148 /*
 149  * The only special thing we need to do here is to make sure that all
 150  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 151  * that sync() will call the filesystem's write_super callback if
 152  * appropriate.
 153  */
 154 int __ext4_journal_stop(const char *where, handle_t *handle)
 155 {
 156         struct super_block *sb;
 157         int err;
 158         int rc;
 159
 160         sb = handle->h_transaction->t_journal->j_private;
 161         err = handle->h_err;
 162         rc = jbd2_journal_stop(handle);
 163
 164         if (!err)
 165                 err = rc;
 166         if (err)
 167                 __ext4_std_error(sb, where, err);
 168         return err;
 169 }
 170
 171 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 172                 struct buffer_head *bh, handle_t *handle, int err)
 173 {
 174         char nbuf[16];
 175         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 176
 177         if (bh)
 178                 BUFFER_TRACE(bh, "abort");
 179
 180         if (!handle->h_err)
 181                 handle->h_err = err;
 182
 183         if (is_handle_aborted(handle))
 184                 return;
 185
 186         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
 187                caller, errstr, err_fn);
 188
 189         jbd2_journal_abort_handle(handle);
 190 }
 191
 192 /* Deal with the reporting of failure conditions on a filesystem such as
 193  * inconsistencies detected or read IO failures.
 194  *
 195  * On ext2, we can store the error state of the filesystem in the
 196  * superblock.  That is not possible on ext4, because we may have other
 197  * write ordering constraints on the superblock which prevent us from
 198  * writing it out straight away; and given that the journal is about to
 199  * be aborted, we can't rely on the current, or future, transactions to
 200  * write out the superblock safely.
 201  *
 202  * We'll just use the jbd2_journal_abort() error code to record an error in
 203  * the journal instead.  On recovery, the journal will compain about
 204  * that error until we've noted it down and cleared it.
 205  */
 206
 207 static void ext4_handle_error(struct super_block *sb)
 208 {
 209         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 210
 211         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 212         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 213
 214         if (sb->s_flags & MS_RDONLY)
 215                 return;
 216
 217         if (!test_opt(sb, ERRORS_CONT)) {
 218                 journal_t *journal = EXT4_SB(sb)->s_journal;
 219
 220                 EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 221                 if (journal)
 222                         jbd2_journal_abort(journal, -EIO);
 223         }
 224         if (test_opt(sb, ERRORS_RO)) {
 225                 printk(KERN_CRIT "Remounting filesystem read-only\n");
 226                 sb->s_flags |= MS_RDONLY;
 227         }
 228         ext4_commit_super(sb, es, 1);
 229         if (test_opt(sb, ERRORS_PANIC))
 230                 panic("EXT4-fs (device %s): panic forced after error\n",
 231                         sb->s_id);
 232 }
 233
 234 void ext4_error(struct super_block *sb, const char *function,
 235                 const char *fmt, ...)
 236 {
 237         va_list args;
 238
 239         va_start(args, fmt);
 240         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 241         vprintk(fmt, args);
 242         printk("\n");
 243         va_end(args);
 244
 245         ext4_handle_error(sb);
 246 }
 247
 248 static const char *ext4_decode_error(struct super_block *sb, int errno,
 249                                      char nbuf[16])
 250 {
 251         char *errstr = NULL;
 252
 253         switch (errno) {
 254         case -EIO:
 255                 errstr = "IO failure";
 256                 break;
 257         case -ENOMEM:
 258                 errstr = "Out of memory";
 259                 break;
 260         case -EROFS:
 261                 if (!sb || EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT)
 262                         errstr = "Journal has aborted";
 263                 else
 264                         errstr = "Readonly filesystem";
 265                 break;
 266         default:
 267                 /* If the caller passed in an extra buffer for unknown
 268                  * errors, textualise them now.  Else we just return
 269                  * NULL. */
 270                 if (nbuf) {
 271                         /* Check for truncated error codes... */
 272                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 273                                 errstr = nbuf;
 274                 }
 275                 break;
 276         }
 277
 278         return errstr;
 279 }
 280
 281 /* __ext4_std_error decodes expected errors from journaling functions
 282  * automatically and invokes the appropriate error response.  */
 283
 284 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
 285 {
 286         char nbuf[16];
 287         const char *errstr;
 288
 289         /* Special case: if the error is EROFS, and we're not already
 290          * inside a transaction, then there's really no point in logging
 291          * an error. */
 292         if (errno == -EROFS && journal_current_handle() == NULL &&
 293             (sb->s_flags & MS_RDONLY))
 294                 return;
 295
 296         errstr = ext4_decode_error(sb, errno, nbuf);
 297         printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
 298                sb->s_id, function, errstr);
 299
 300         ext4_handle_error(sb);
 301 }
 302
 303 /*
 304  * ext4_abort is a much stronger failure handler than ext4_error.  The
 305  * abort function may be used to deal with unrecoverable failures such
 306  * as journal IO errors or ENOMEM at a critical moment in log management.
 307  *
 308  * We unconditionally force the filesystem into an ABORT|READONLY state,
 309  * unless the error response on the fs has been set to panic in which
 310  * case we take the easy way out and panic immediately.
 311  */
 312
 313 void ext4_abort(struct super_block *sb, const char *function,
 314                 const char *fmt, ...)
 315 {
 316         va_list args;
 317
 318         printk(KERN_CRIT "ext4_abort called.\n");
 319
 320         va_start(args, fmt);
 321         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 322         vprintk(fmt, args);
 323         printk("\n");
 324         va_end(args);
 325
 326         if (test_opt(sb, ERRORS_PANIC))
 327                 panic("EXT4-fs panic from previous error\n");
 328
 329         if (sb->s_flags & MS_RDONLY)
 330                 return;
 331
 332         printk(KERN_CRIT "Remounting filesystem read-only\n");
 333         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 334         sb->s_flags |= MS_RDONLY;
 335         EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 336         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 337 }
 338
 339 void ext4_warning(struct super_block *sb, const char *function,
 340                   const char *fmt, ...)
 341 {
 342         va_list args;
 343
 344         va_start(args, fmt);
 345         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
 346                sb->s_id, function);
 347         vprintk(fmt, args);
 348         printk("\n");
 349         va_end(args);
 350 }
 351
 352 void ext4_update_dynamic_rev(struct super_block *sb)
 353 {
 354         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 355
 356         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 357                 return;
 358
 359         ext4_warning(sb, __func__,
 360                      "updating to rev %d because of new feature flag, "
 361                      "running e2fsck is recommended",
 362                      EXT4_DYNAMIC_REV);
 363
 364         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 365         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 366         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 367         /* leave es->s_feature_*compat flags alone */
 368         /* es->s_uuid will be set by e2fsck if empty */
 369
 370         /*
 371          * The rest of the superblock fields should be zero, and if not it
 372          * means they are likely already in use, so leave them alone.  We
 373          * can leave it up to e2fsck to clean up any inconsistencies there.
 374          */
 375 }
 376
 377 int ext4_update_compat_feature(handle_t *handle,
 378                                         struct super_block *sb, __u32 compat)
 379 {
 380         int err = 0;
 381         if (!EXT4_HAS_COMPAT_FEATURE(sb, compat)) {
 382                 err = ext4_journal_get_write_access(handle,
 383                                 EXT4_SB(sb)->s_sbh);
 384                 if (err)
 385                         return err;
 386                 EXT4_SET_COMPAT_FEATURE(sb, compat);
 387                 sb->s_dirt = 1;
 388                 handle->h_sync = 1;
 389                 BUFFER_TRACE(EXT4_SB(sb)->s_sbh,
 390                                         "call ext4_journal_dirty_met adata");
 391                 err = ext4_journal_dirty_metadata(handle,
 392                                 EXT4_SB(sb)->s_sbh);
 393         }
 394         return err;
 395 }
 396
 397 int ext4_update_rocompat_feature(handle_t *handle,
 398                                         struct super_block *sb, __u32 rocompat)
 399 {
 400         int err = 0;
 401         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, rocompat)) {
 402                 err = ext4_journal_get_write_access(handle,
 403                                 EXT4_SB(sb)->s_sbh);
 404                 if (err)
 405                         return err;
 406                 EXT4_SET_RO_COMPAT_FEATURE(sb, rocompat);
 407                 sb->s_dirt = 1;
 408                 handle->h_sync = 1;
 409                 BUFFER_TRACE(EXT4_SB(sb)->s_sbh,
 410                                         "call ext4_journal_dirty_met adata");
 411                 err = ext4_journal_dirty_metadata(handle,
 412                                 EXT4_SB(sb)->s_sbh);
 413         }
 414         return err;
 415 }
 416
 417 int ext4_update_incompat_feature(handle_t *handle,
 418                                         struct super_block *sb, __u32 incompat)
 419 {
 420         int err = 0;
 421         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, incompat)) {
 422                 err = ext4_journal_get_write_access(handle,
 423                                 EXT4_SB(sb)->s_sbh);
 424                 if (err)
 425                         return err;
 426                 EXT4_SET_INCOMPAT_FEATURE(sb, incompat);
 427                 sb->s_dirt = 1;
 428                 handle->h_sync = 1;
 429                 BUFFER_TRACE(EXT4_SB(sb)->s_sbh,
 430                                         "call ext4_journal_dirty_met adata");
 431                 err = ext4_journal_dirty_metadata(handle,
 432                                 EXT4_SB(sb)->s_sbh);
 433         }
 434         return err;
 435 }
 436
 437 /*
 438  * Open the external journal device
 439  */
 440 static struct block_device *ext4_blkdev_get(dev_t dev)
 441 {
 442         struct block_device *bdev;
 443         char b[BDEVNAME_SIZE];
 444
 445         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 446         if (IS_ERR(bdev))
 447                 goto fail;
 448         return bdev;
 449
 450 fail:
 451         printk(KERN_ERR "EXT4: failed to open journal device %s: %ld\n",
 452                         __bdevname(dev, b), PTR_ERR(bdev));
 453         return NULL;
 454 }
 455
 456 /*
 457  * Release the journal device
 458  */
 459 static int ext4_blkdev_put(struct block_device *bdev)
 460 {
 461         bd_release(bdev);
 462         return blkdev_put(bdev);
 463 }
 464
 465 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 466 {
 467         struct block_device *bdev;
 468         int ret = -ENODEV;
 469
 470         bdev = sbi->journal_bdev;
 471         if (bdev) {
 472                 ret = ext4_blkdev_put(bdev);
 473                 sbi->journal_bdev = NULL;
 474         }
 475         return ret;
 476 }
 477
 478 static inline struct inode *orphan_list_entry(struct list_head *l)
 479 {
 480         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 481 }
 482
 483 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 484 {
 485         struct list_head *l;
 486
 487         printk(KERN_ERR "sb orphan head is %d\n",
 488                le32_to_cpu(sbi->s_es->s_last_orphan));
 489
 490         printk(KERN_ERR "sb_info orphan list:\n");
 491         list_for_each(l, &sbi->s_orphan) {
 492                 struct inode *inode = orphan_list_entry(l);
 493                 printk(KERN_ERR "  "
 494                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 495                        inode->i_sb->s_id, inode->i_ino, inode,
 496                        inode->i_mode, inode->i_nlink,
 497                        NEXT_ORPHAN(inode));
 498         }
 499 }
 500
 501 static void ext4_put_super(struct super_block *sb)
 502 {
 503         struct ext4_sb_info *sbi = EXT4_SB(sb);
 504         struct ext4_super_block *es = sbi->s_es;
 505         int i;
 506
 507         ext4_mb_release(sb);
 508         ext4_ext_release(sb);
 509         ext4_xattr_put_super(sb);
 510         jbd2_journal_destroy(sbi->s_journal);
 511         sbi->s_journal = NULL;
 512         if (!(sb->s_flags & MS_RDONLY)) {
 513                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 514                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 515                 ext4_commit_super(sb, es, 1);
 516         }
 517         if (sbi->s_proc) {
 518                 remove_proc_entry("inode_readahead_blks", sbi->s_proc);
 519                 remove_proc_entry(sb->s_id, ext4_proc_root);
 520         }
 521
 522         for (i = 0; i < sbi->s_gdb_count; i++)
 523                 brelse(sbi->s_group_desc[i]);
 524         kfree(sbi->s_group_desc);
 525         kfree(sbi->s_flex_groups);
 526         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 527         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 528         percpu_counter_destroy(&sbi->s_dirs_counter);
 529         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
 530         brelse(sbi->s_sbh);
 531 #ifdef CONFIG_QUOTA
 532         for (i = 0; i < MAXQUOTAS; i++)
 533                 kfree(sbi->s_qf_names[i]);
 534 #endif
 535
 536         /* Debugging code just in case the in-memory inode orphan list
 537          * isn't empty.  The on-disk one can be non-empty if we've
 538          * detected an error and taken the fs readonly, but the
 539          * in-memory list had better be clean by this point. */
 540         if (!list_empty(&sbi->s_orphan))
 541                 dump_orphan_list(sb, sbi);
 542         J_ASSERT(list_empty(&sbi->s_orphan));
 543
 544         invalidate_bdev(sb->s_bdev);
 545         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 546                 /*
 547                  * Invalidate the journal device's buffers.  We don't want them
 548                  * floating about in memory - the physical journal device may
 549                  * hotswapped, and it breaks the `ro-after' testing code.
 550                  */
 551                 sync_blockdev(sbi->journal_bdev);
 552                 invalidate_bdev(sbi->journal_bdev);
 553                 ext4_blkdev_remove(sbi);
 554         }
 555         sb->s_fs_info = NULL;
 556         kfree(sbi);
 557         return;
 558 }
 559
 560 static struct kmem_cache *ext4_inode_cachep;
 561
 562 /*
 563  * Called inside transaction, so use GFP_NOFS
 564  */
 565 static struct inode *ext4_alloc_inode(struct super_block *sb)
 566 {
 567         struct ext4_inode_info *ei;
 568
 569         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 570         if (!ei)
 571                 return NULL;
 572 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 573         ei->i_acl = EXT4_ACL_NOT_CACHED;
 574         ei->i_default_acl = EXT4_ACL_NOT_CACHED;
 575 #endif
 576         ei->vfs_inode.i_version = 1;
 577         ei->vfs_inode.i_data.writeback_index = 0;
 578         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 579         INIT_LIST_HEAD(&ei->i_prealloc_list);
 580         spin_lock_init(&ei->i_prealloc_lock);
 581         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
 582         ei->i_reserved_data_blocks = 0;
 583         ei->i_reserved_meta_blocks = 0;
 584         ei->i_allocated_meta_blocks = 0;
 585         ei->i_delalloc_reserved_flag = 0;
 586         spin_lock_init(&(ei->i_block_reservation_lock));
 587         return &ei->vfs_inode;
 588 }
 589
 590 static void ext4_destroy_inode(struct inode *inode)
 591 {
 592         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 593                 printk("EXT4 Inode %p: orphan list check failed!\n",
 594                         EXT4_I(inode));
 595                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 596                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 597                                 true);
 598                 dump_stack();
 599         }
 600         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 601 }
 602
 603 static void init_once(void *foo)
 604 {
 605         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 606
 607         INIT_LIST_HEAD(&ei->i_orphan);
 608 #ifdef CONFIG_EXT4_FS_XATTR
 609         init_rwsem(&ei->xattr_sem);
 610 #endif
 611         init_rwsem(&ei->i_data_sem);
 612         inode_init_once(&ei->vfs_inode);
 613 }
 614
 615 static int init_inodecache(void)
 616 {
 617         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 618                                              sizeof(struct ext4_inode_info),
 619                                              0, (SLAB_RECLAIM_ACCOUNT|
 620                                                 SLAB_MEM_SPREAD),
 621                                              init_once);
 622         if (ext4_inode_cachep == NULL)
 623                 return -ENOMEM;
 624         return 0;
 625 }
 626
 627 static void destroy_inodecache(void)
 628 {
 629         kmem_cache_destroy(ext4_inode_cachep);
 630 }
 631
 632 static void ext4_clear_inode(struct inode *inode)
 633 {
 634 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 635         if (EXT4_I(inode)->i_acl &&
 636                         EXT4_I(inode)->i_acl != EXT4_ACL_NOT_CACHED) {
 637                 posix_acl_release(EXT4_I(inode)->i_acl);
 638                 EXT4_I(inode)->i_acl = EXT4_ACL_NOT_CACHED;
 639         }
 640         if (EXT4_I(inode)->i_default_acl &&
 641                         EXT4_I(inode)->i_default_acl != EXT4_ACL_NOT_CACHED) {
 642                 posix_acl_release(EXT4_I(inode)->i_default_acl);
 643                 EXT4_I(inode)->i_default_acl = EXT4_ACL_NOT_CACHED;
 644         }
 645 #endif
 646         ext4_discard_preallocations(inode);
 647         jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
 648                                        &EXT4_I(inode)->jinode);
 649 }
 650
 651 static inline void ext4_show_quota_options(struct seq_file *seq,
 652                                            struct super_block *sb)
 653 {
 654 #if defined(CONFIG_QUOTA)
 655         struct ext4_sb_info *sbi = EXT4_SB(sb);
 656
 657         if (sbi->s_jquota_fmt)
 658                 seq_printf(seq, ",jqfmt=%s",
 659                 (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold" : "vfsv0");
 660
 661         if (sbi->s_qf_names[USRQUOTA])
 662                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 663
 664         if (sbi->s_qf_names[GRPQUOTA])
 665                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 666
 667         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
 668                 seq_puts(seq, ",usrquota");
 669
 670         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
 671                 seq_puts(seq, ",grpquota");
 672 #endif
 673 }
 674
 675 /*
 676  * Show an option if
 677  *  - it's set to a non-default value OR
 678  *  - if the per-sb default is different from the global default
 679  */
 680 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 681 {
 682         int def_errors;
 683         unsigned long def_mount_opts;
 684         struct super_block *sb = vfs->mnt_sb;
 685         struct ext4_sb_info *sbi = EXT4_SB(sb);
 686         struct ext4_super_block *es = sbi->s_es;
 687
 688         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 689         def_errors     = le16_to_cpu(es->s_errors);
 690
 691         if (sbi->s_sb_block != 1)
 692                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
 693         if (test_opt(sb, MINIX_DF))
 694                 seq_puts(seq, ",minixdf");
 695         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
 696                 seq_puts(seq, ",grpid");
 697         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
 698                 seq_puts(seq, ",nogrpid");
 699         if (sbi->s_resuid != EXT4_DEF_RESUID ||
 700             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
 701                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
 702         }
 703         if (sbi->s_resgid != EXT4_DEF_RESGID ||
 704             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
 705                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
 706         }
 707         if (test_opt(sb, ERRORS_RO)) {
 708                 if (def_errors == EXT4_ERRORS_PANIC ||
 709                     def_errors == EXT4_ERRORS_CONTINUE) {
 710                         seq_puts(seq, ",errors=remount-ro");
 711                 }
 712         }
 713         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
 714                 seq_puts(seq, ",errors=continue");
 715         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
 716                 seq_puts(seq, ",errors=panic");
 717         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
 718                 seq_puts(seq, ",nouid32");
 719         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
 720                 seq_puts(seq, ",debug");
 721         if (test_opt(sb, OLDALLOC))
 722                 seq_puts(seq, ",oldalloc");
 723 #ifdef CONFIG_EXT4_FS_XATTR
 724         if (test_opt(sb, XATTR_USER) &&
 725                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
 726                 seq_puts(seq, ",user_xattr");
 727         if (!test_opt(sb, XATTR_USER) &&
 728             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
 729                 seq_puts(seq, ",nouser_xattr");
 730         }
 731 #endif
 732 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 733         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
 734                 seq_puts(seq, ",acl");
 735         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
 736                 seq_puts(seq, ",noacl");
 737 #endif
 738         if (!test_opt(sb, RESERVATION))
 739                 seq_puts(seq, ",noreservation");
 740         if (sbi->s_commit_interval) {
 741                 seq_printf(seq, ",commit=%u",
 742                            (unsigned) (sbi->s_commit_interval / HZ));
 743         }
 744         /*
 745          * We're changing the default of barrier mount option, so
 746          * let's always display its mount state so it's clear what its
 747          * status is.
 748          */
 749         seq_puts(seq, ",barrier=");
 750         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
 751         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
 752                 seq_puts(seq, ",journal_async_commit");
 753         if (test_opt(sb, NOBH))
 754                 seq_puts(seq, ",nobh");
 755         if (!test_opt(sb, EXTENTS))
 756                 seq_puts(seq, ",noextents");
 757         if (test_opt(sb, I_VERSION))
 758                 seq_puts(seq, ",i_version");
 759         if (!test_opt(sb, DELALLOC))
 760                 seq_puts(seq, ",nodelalloc");
 761
 762
 763         if (sbi->s_stripe)
 764                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
 765         /*
 766          * journal mode get enabled in different ways
 767          * So just print the value even if we didn't specify it
 768          */
 769         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 770                 seq_puts(seq, ",data=journal");
 771         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 772                 seq_puts(seq, ",data=ordered");
 773         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 774                 seq_puts(seq, ",data=writeback");
 775
 776         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
 777                 seq_printf(seq, ",inode_readahead_blks=%u",
 778                            sbi->s_inode_readahead_blks);
 779
 780         ext4_show_quota_options(seq, sb);
 781         return 0;
 782 }
 783
 784
 785 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 786                 u64 ino, u32 generation)
 787 {
 788         struct inode *inode;
 789
 790         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 791                 return ERR_PTR(-ESTALE);
 792         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 793                 return ERR_PTR(-ESTALE);
 794
 795         /* iget isn't really right if the inode is currently unallocated!!
 796          *
 797          * ext4_read_inode will return a bad_inode if the inode had been
 798          * deleted, so we should be safe.
 799          *
 800          * Currently we don't know the generation for parent directory, so
 801          * a generation of 0 means "accept any"
 802          */
 803         inode = ext4_iget(sb, ino);
 804         if (IS_ERR(inode))
 805                 return ERR_CAST(inode);
 806         if (generation && inode->i_generation != generation) {
 807                 iput(inode);
 808                 return ERR_PTR(-ESTALE);
 809         }
 810
 811         return inode;
 812 }
 813
 814 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
 815                 int fh_len, int fh_type)
 816 {
 817         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 818                                     ext4_nfs_get_inode);
 819 }
 820
 821 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
 822                 int fh_len, int fh_type)
 823 {
 824         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 825                                     ext4_nfs_get_inode);
 826 }
 827
 828 #ifdef CONFIG_QUOTA
 829 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
 830 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
 831
 832 static int ext4_dquot_initialize(struct inode *inode, int type);
 833 static int ext4_dquot_drop(struct inode *inode);
 834 static int ext4_write_dquot(struct dquot *dquot);
 835 static int ext4_acquire_dquot(struct dquot *dquot);
 836 static int ext4_release_dquot(struct dquot *dquot);
 837 static int ext4_mark_dquot_dirty(struct dquot *dquot);
 838 static int ext4_write_info(struct super_block *sb, int type);
 839 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
 840                                 char *path, int remount);
 841 static int ext4_quota_on_mount(struct super_block *sb, int type);
 842 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
 843                                size_t len, loff_t off);
 844 static ssize_t ext4_quota_write(struct super_block *sb, int type,
 845                                 const char *data, size_t len, loff_t off);
 846
 847 static struct dquot_operations ext4_quota_operations = {
 848         .initialize     = ext4_dquot_initialize,
 849         .drop           = ext4_dquot_drop,
 850         .alloc_space    = dquot_alloc_space,
 851         .alloc_inode    = dquot_alloc_inode,
 852         .free_space     = dquot_free_space,
 853         .free_inode     = dquot_free_inode,
 854         .transfer       = dquot_transfer,
 855         .write_dquot    = ext4_write_dquot,
 856         .acquire_dquot  = ext4_acquire_dquot,
 857         .release_dquot  = ext4_release_dquot,
 858         .mark_dirty     = ext4_mark_dquot_dirty,
 859         .write_info     = ext4_write_info
 860 };
 861
 862 static struct quotactl_ops ext4_qctl_operations = {
 863         .quota_on       = ext4_quota_on,
 864         .quota_off      = vfs_quota_off,
 865         .quota_sync     = vfs_quota_sync,
 866         .get_info       = vfs_get_dqinfo,
 867         .set_info       = vfs_set_dqinfo,
 868         .get_dqblk      = vfs_get_dqblk,
 869         .set_dqblk      = vfs_set_dqblk
 870 };
 871 #endif
 872
 873 static const struct super_operations ext4_sops = {
 874         .alloc_inode    = ext4_alloc_inode,
 875         .destroy_inode  = ext4_destroy_inode,
 876         .write_inode    = ext4_write_inode,
 877         .dirty_inode    = ext4_dirty_inode,
 878         .delete_inode   = ext4_delete_inode,
 879         .put_super      = ext4_put_super,
 880         .write_super    = ext4_write_super,
 881         .sync_fs        = ext4_sync_fs,
 882         .write_super_lockfs = ext4_write_super_lockfs,
 883         .unlockfs       = ext4_unlockfs,
 884         .statfs         = ext4_statfs,
 885         .remount_fs     = ext4_remount,
 886         .clear_inode    = ext4_clear_inode,
 887         .show_options   = ext4_show_options,
 888 #ifdef CONFIG_QUOTA
 889         .quota_read     = ext4_quota_read,
 890         .quota_write    = ext4_quota_write,
 891 #endif
 892 };
 893
 894 static const struct export_operations ext4_export_ops = {
 895         .fh_to_dentry = ext4_fh_to_dentry,
 896         .fh_to_parent = ext4_fh_to_parent,
 897         .get_parent = ext4_get_parent,
 898 };
 899
 900 enum {
 901         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
 902         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
 903         Opt_nouid32, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov,
 904         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
 905         Opt_reservation, Opt_noreservation, Opt_noload, Opt_nobh, Opt_bh,
 906         Opt_commit, Opt_journal_update, Opt_journal_inum, Opt_journal_dev,
 907         Opt_journal_checksum, Opt_journal_async_commit,
 908         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
 909         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
 910         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
 911         Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
 912         Opt_grpquota, Opt_extents, Opt_noextents, Opt_i_version,
 913         Opt_mballoc, Opt_nomballoc, Opt_stripe, Opt_delalloc, Opt_nodelalloc,
 914         Opt_inode_readahead_blks
 915 };
 916
 917 static match_table_t tokens = {
 918         {Opt_bsd_df, "bsddf"},
 919         {Opt_minix_df, "minixdf"},
 920         {Opt_grpid, "grpid"},
 921         {Opt_grpid, "bsdgroups"},
 922         {Opt_nogrpid, "nogrpid"},
 923         {Opt_nogrpid, "sysvgroups"},
 924         {Opt_resgid, "resgid=%u"},
 925         {Opt_resuid, "resuid=%u"},
 926         {Opt_sb, "sb=%u"},
 927         {Opt_err_cont, "errors=continue"},
 928         {Opt_err_panic, "errors=panic"},
 929         {Opt_err_ro, "errors=remount-ro"},
 930         {Opt_nouid32, "nouid32"},
 931         {Opt_nocheck, "nocheck"},
 932         {Opt_nocheck, "check=none"},
 933         {Opt_debug, "debug"},
 934         {Opt_oldalloc, "oldalloc"},
 935         {Opt_orlov, "orlov"},
 936         {Opt_user_xattr, "user_xattr"},
 937         {Opt_nouser_xattr, "nouser_xattr"},
 938         {Opt_acl, "acl"},
 939         {Opt_noacl, "noacl"},
 940         {Opt_reservation, "reservation"},
 941         {Opt_noreservation, "noreservation"},
 942         {Opt_noload, "noload"},
 943         {Opt_nobh, "nobh"},
 944         {Opt_bh, "bh"},
 945         {Opt_commit, "commit=%u"},
 946         {Opt_journal_update, "journal=update"},
 947         {Opt_journal_inum, "journal=%u"},
 948         {Opt_journal_dev, "journal_dev=%u"},
 949         {Opt_journal_checksum, "journal_checksum"},
 950         {Opt_journal_async_commit, "journal_async_commit"},
 951         {Opt_abort, "abort"},
 952         {Opt_data_journal, "data=journal"},
 953         {Opt_data_ordered, "data=ordered"},
 954         {Opt_data_writeback, "data=writeback"},
 955         {Opt_offusrjquota, "usrjquota="},
 956         {Opt_usrjquota, "usrjquota=%s"},
 957         {Opt_offgrpjquota, "grpjquota="},
 958         {Opt_grpjquota, "grpjquota=%s"},
 959         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
 960         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
 961         {Opt_grpquota, "grpquota"},
 962         {Opt_noquota, "noquota"},
 963         {Opt_quota, "quota"},
 964         {Opt_usrquota, "usrquota"},
 965         {Opt_barrier, "barrier=%u"},
 966         {Opt_extents, "extents"},
 967         {Opt_noextents, "noextents"},
 968         {Opt_i_version, "i_version"},
 969         {Opt_mballoc, "mballoc"},
 970         {Opt_nomballoc, "nomballoc"},
 971         {Opt_stripe, "stripe=%u"},
 972         {Opt_resize, "resize"},
 973         {Opt_delalloc, "delalloc"},
 974         {Opt_nodelalloc, "nodelalloc"},
 975         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
 976         {Opt_err, NULL},
 977 };
 978
 979 static ext4_fsblk_t get_sb_block(void **data)
 980 {
 981         ext4_fsblk_t    sb_block;
 982         char            *options = (char *) *data;
 983
 984         if (!options || strncmp(options, "sb=", 3) != 0)
 985                 return 1;       /* Default location */
 986         options += 3;
 987         /*todo: use simple_strtoll with >32bit ext4 */
 988         sb_block = simple_strtoul(options, &options, 0);
 989         if (*options && *options != ',') {
 990                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
 991                        (char *) *data);
 992                 return 1;
 993         }
 994         if (*options == ',')
 995                 options++;
 996         *data = (void *) options;
 997         return sb_block;
 998 }
 999
1000 static int parse_options(char *options, struct super_block *sb,
1001                          unsigned int *inum, unsigned long *journal_devnum,
1002                          ext4_fsblk_t *n_blocks_count, int is_remount)
1003 {
1004         struct ext4_sb_info *sbi = EXT4_SB(sb);
1005         char *p;
1006         substring_t args[MAX_OPT_ARGS];
1007         int data_opt = 0;
1008         int option;
1009 #ifdef CONFIG_QUOTA
1010         int qtype, qfmt;
1011         char *qname;
1012 #endif
1013         ext4_fsblk_t last_block;
1014
1015         if (!options)
1016                 return 1;
1017
1018         while ((p = strsep(&options, ",")) != NULL) {
1019                 int token;
1020                 if (!*p)
1021                         continue;
1022
1023                 token = match_token(p, tokens, args);
1024                 switch (token) {
1025                 case Opt_bsd_df:
1026                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1027                         break;
1028                 case Opt_minix_df:
1029                         set_opt(sbi->s_mount_opt, MINIX_DF);
1030                         break;
1031                 case Opt_grpid:
1032                         set_opt(sbi->s_mount_opt, GRPID);
1033                         break;
1034                 case Opt_nogrpid:
1035                         clear_opt(sbi->s_mount_opt, GRPID);
1036                         break;
1037                 case Opt_resuid:
1038                         if (match_int(&args[0], &option))
1039                                 return 0;
1040                         sbi->s_resuid = option;
1041                         break;
1042                 case Opt_resgid:
1043                         if (match_int(&args[0], &option))
1044                                 return 0;
1045                         sbi->s_resgid = option;
1046                         break;
1047                 case Opt_sb:
1048                         /* handled by get_sb_block() instead of here */
1049                         /* *sb_block = match_int(&args[0]); */
1050                         break;
1051                 case Opt_err_panic:
1052                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1053                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1054                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1055                         break;
1056                 case Opt_err_ro:
1057                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1058                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1059                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1060                         break;
1061                 case Opt_err_cont:
1062                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1063                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1064                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1065                         break;
1066                 case Opt_nouid32:
1067                         set_opt(sbi->s_mount_opt, NO_UID32);
1068                         break;
1069                 case Opt_nocheck:
1070                         clear_opt(sbi->s_mount_opt, CHECK);
1071                         break;
1072                 case Opt_debug:
1073                         set_opt(sbi->s_mount_opt, DEBUG);
1074                         break;
1075                 case Opt_oldalloc:
1076                         set_opt(sbi->s_mount_opt, OLDALLOC);
1077                         break;
1078                 case Opt_orlov:
1079                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1080                         break;
1081 #ifdef CONFIG_EXT4_FS_XATTR
1082                 case Opt_user_xattr:
1083                         set_opt(sbi->s_mount_opt, XATTR_USER);
1084                         break;
1085                 case Opt_nouser_xattr:
1086                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1087                         break;
1088 #else
1089                 case Opt_user_xattr:
1090                 case Opt_nouser_xattr:
1091                         printk(KERN_ERR "EXT4 (no)user_xattr options "
1092                                "not supported\n");
1093                         break;
1094 #endif
1095 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1096                 case Opt_acl:
1097                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1098                         break;
1099                 case Opt_noacl:
1100                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1101                         break;
1102 #else
1103                 case Opt_acl:
1104                 case Opt_noacl:
1105                         printk(KERN_ERR "EXT4 (no)acl options "
1106                                "not supported\n");
1107                         break;
1108 #endif
1109                 case Opt_reservation:
1110                         set_opt(sbi->s_mount_opt, RESERVATION);
1111                         break;
1112                 case Opt_noreservation:
1113                         clear_opt(sbi->s_mount_opt, RESERVATION);
1114                         break;
1115                 case Opt_journal_update:
1116                         /* @@@ FIXME */
1117                         /* Eventually we will want to be able to create
1118                            a journal file here.  For now, only allow the
1119                            user to specify an existing inode to be the
1120                            journal file. */
1121                         if (is_remount) {
1122                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1123                                        "journal on remount\n");
1124                                 return 0;
1125                         }
1126                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1127                         break;
1128                 case Opt_journal_inum:
1129                         if (is_remount) {
1130                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1131                                        "journal on remount\n");
1132                                 return 0;
1133                         }
1134                         if (match_int(&args[0], &option))
1135                                 return 0;
1136                         *inum = option;
1137                         break;
1138                 case Opt_journal_dev:
1139                         if (is_remount) {
1140                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1141                                        "journal on remount\n");
1142                                 return 0;
1143                         }
1144                         if (match_int(&args[0], &option))
1145                                 return 0;
1146                         *journal_devnum = option;
1147                         break;
1148                 case Opt_journal_checksum:
1149                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1150                         break;
1151                 case Opt_journal_async_commit:
1152                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1153                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1154                         break;
1155                 case Opt_noload:
1156                         set_opt(sbi->s_mount_opt, NOLOAD);
1157                         break;
1158                 case Opt_commit:
1159                         if (match_int(&args[0], &option))
1160                                 return 0;
1161                         if (option < 0)
1162                                 return 0;
1163                         if (option == 0)
1164                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1165                         sbi->s_commit_interval = HZ * option;
1166                         break;
1167                 case Opt_data_journal:
1168                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1169                         goto datacheck;
1170                 case Opt_data_ordered:
1171                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1172                         goto datacheck;
1173                 case Opt_data_writeback:
1174                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1175                 datacheck:
1176                         if (is_remount) {
1177                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1178                                                 != data_opt) {
1179                                         printk(KERN_ERR
1180                                                 "EXT4-fs: cannot change data "
1181                                                 "mode on remount\n");
1182                                         return 0;
1183                                 }
1184                         } else {
1185                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1186                                 sbi->s_mount_opt |= data_opt;
1187                         }
1188                         break;
1189 #ifdef CONFIG_QUOTA
1190                 case Opt_usrjquota:
1191                         qtype = USRQUOTA;
1192                         goto set_qf_name;
1193                 case Opt_grpjquota:
1194                         qtype = GRPQUOTA;
1195 set_qf_name:
1196                         if ((sb_any_quota_enabled(sb) ||
1197                              sb_any_quota_suspended(sb)) &&
1198                             !sbi->s_qf_names[qtype]) {
1199                                 printk(KERN_ERR
1200                                        "EXT4-fs: Cannot change journaled "
1201                                        "quota options when quota turned on.\n");
1202                                 return 0;
1203                         }
1204                         qname = match_strdup(&args[0]);
1205                         if (!qname) {
1206                                 printk(KERN_ERR
1207                                         "EXT4-fs: not enough memory for "
1208                                         "storing quotafile name.\n");
1209                                 return 0;
1210                         }
1211                         if (sbi->s_qf_names[qtype] &&
1212                             strcmp(sbi->s_qf_names[qtype], qname)) {
1213                                 printk(KERN_ERR
1214                                         "EXT4-fs: %s quota file already "
1215                                         "specified.\n", QTYPE2NAME(qtype));
1216                                 kfree(qname);
1217                                 return 0;
1218                         }
1219                         sbi->s_qf_names[qtype] = qname;
1220                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1221                                 printk(KERN_ERR
1222                                         "EXT4-fs: quotafile must be on "
1223                                         "filesystem root.\n");
1224                                 kfree(sbi->s_qf_names[qtype]);
1225                                 sbi->s_qf_names[qtype] = NULL;
1226                                 return 0;
1227                         }
1228                         set_opt(sbi->s_mount_opt, QUOTA);
1229                         break;
1230                 case Opt_offusrjquota:
1231                         qtype = USRQUOTA;
1232                         goto clear_qf_name;
1233                 case Opt_offgrpjquota:
1234                         qtype = GRPQUOTA;
1235 clear_qf_name:
1236                         if ((sb_any_quota_enabled(sb) ||
1237                              sb_any_quota_suspended(sb)) &&
1238                             sbi->s_qf_names[qtype]) {
1239                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1240                                         "journaled quota options when "
1241                                         "quota turned on.\n");
1242                                 return 0;
1243                         }
1244                         /*
1245                          * The space will be released later when all options
1246                          * are confirmed to be correct
1247                          */
1248                         sbi->s_qf_names[qtype] = NULL;
1249                         break;
1250                 case Opt_jqfmt_vfsold:
1251                         qfmt = QFMT_VFS_OLD;
1252                         goto set_qf_format;
1253                 case Opt_jqfmt_vfsv0:
1254                         qfmt = QFMT_VFS_V0;
1255 set_qf_format:
1256                         if ((sb_any_quota_enabled(sb) ||
1257                              sb_any_quota_suspended(sb)) &&
1258                             sbi->s_jquota_fmt != qfmt) {
1259                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1260                                         "journaled quota options when "
1261                                         "quota turned on.\n");
1262                                 return 0;
1263                         }
1264                         sbi->s_jquota_fmt = qfmt;
1265                         break;
1266                 case Opt_quota:
1267                 case Opt_usrquota:
1268                         set_opt(sbi->s_mount_opt, QUOTA);
1269                         set_opt(sbi->s_mount_opt, USRQUOTA);
1270                         break;
1271                 case Opt_grpquota:
1272                         set_opt(sbi->s_mount_opt, QUOTA);
1273                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1274                         break;
1275                 case Opt_noquota:
1276                         if (sb_any_quota_enabled(sb)) {
1277                                 printk(KERN_ERR "EXT4-fs: Cannot change quota "
1278                                         "options when quota turned on.\n");
1279                                 return 0;
1280                         }
1281                         clear_opt(sbi->s_mount_opt, QUOTA);
1282                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1283                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1284                         break;
1285 #else
1286                 case Opt_quota:
1287                 case Opt_usrquota:
1288                 case Opt_grpquota:
1289                         printk(KERN_ERR
1290                                 "EXT4-fs: quota options not supported.\n");
1291                         break;
1292                 case Opt_usrjquota:
1293                 case Opt_grpjquota:
1294                 case Opt_offusrjquota:
1295                 case Opt_offgrpjquota:
1296                 case Opt_jqfmt_vfsold:
1297                 case Opt_jqfmt_vfsv0:
1298                         printk(KERN_ERR
1299                                 "EXT4-fs: journaled quota options not "
1300                                 "supported.\n");
1301                         break;
1302                 case Opt_noquota:
1303                         break;
1304 #endif
1305                 case Opt_abort:
1306                         set_opt(sbi->s_mount_opt, ABORT);
1307                         break;
1308                 case Opt_barrier:
1309                         if (match_int(&args[0], &option))
1310                                 return 0;
1311                         if (option)
1312                                 set_opt(sbi->s_mount_opt, BARRIER);
1313                         else
1314                                 clear_opt(sbi->s_mount_opt, BARRIER);
1315                         break;
1316                 case Opt_ignore:
1317                         break;
1318                 case Opt_resize:
1319                         if (!is_remount) {
1320                                 printk("EXT4-fs: resize option only available "
1321                                         "for remount\n");
1322                                 return 0;
1323                         }
1324                         if (match_int(&args[0], &option) != 0)
1325                                 return 0;
1326                         *n_blocks_count = option;
1327                         break;
1328                 case Opt_nobh:
1329                         set_opt(sbi->s_mount_opt, NOBH);
1330                         break;
1331                 case Opt_bh:
1332                         clear_opt(sbi->s_mount_opt, NOBH);
1333                         break;
1334                 case Opt_extents:
1335                         if (!EXT4_HAS_INCOMPAT_FEATURE(sb,
1336                                         EXT4_FEATURE_INCOMPAT_EXTENTS)) {
1337                                 ext4_warning(sb, __func__,
1338                                         "extents feature not enabled "
1339                                         "on this filesystem, use tune2fs\n");
1340                                 return 0;
1341                         }
1342                         set_opt(sbi->s_mount_opt, EXTENTS);
1343                         break;
1344                 case Opt_noextents:
1345                         /*
1346                          * When e2fsprogs support resizing an already existing
1347                          * ext3 file system to greater than 2**32 we need to
1348                          * add support to block allocator to handle growing
1349                          * already existing block  mapped inode so that blocks
1350                          * allocated for them fall within 2**32
1351                          */
1352                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1353                         if (last_block  > 0xffffffffULL) {
1354                                 printk(KERN_ERR "EXT4-fs: Filesystem too "
1355                                                 "large to mount with "
1356                                                 "-o noextents options\n");
1357                                 return 0;
1358                         }
1359                         clear_opt(sbi->s_mount_opt, EXTENTS);
1360                         break;
1361                 case Opt_i_version:
1362                         set_opt(sbi->s_mount_opt, I_VERSION);
1363                         sb->s_flags |= MS_I_VERSION;
1364                         break;
1365                 case Opt_nodelalloc:
1366                         clear_opt(sbi->s_mount_opt, DELALLOC);
1367                         break;
1368                 case Opt_stripe:
1369                         if (match_int(&args[0], &option))
1370                                 return 0;
1371                         if (option < 0)
1372                                 return 0;
1373                         sbi->s_stripe = option;
1374                         break;
1375                 case Opt_delalloc:
1376                         set_opt(sbi->s_mount_opt, DELALLOC);
1377                         break;
1378                 case Opt_inode_readahead_blks:
1379                         if (match_int(&args[0], &option))
1380                                 return 0;
1381                         if (option < 0 || option > (1 << 30))
1382                                 return 0;
1383                         sbi->s_inode_readahead_blks = option;
1384                         break;
1385                 default:
1386                         printk(KERN_ERR
1387                                "EXT4-fs: Unrecognized mount option \"%s\" "
1388                                "or missing value\n", p);
1389                         return 0;
1390                 }
1391         }
1392 #ifdef CONFIG_QUOTA
1393         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1394                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1395                      sbi->s_qf_names[USRQUOTA])
1396                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1397
1398                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1399                      sbi->s_qf_names[GRPQUOTA])
1400                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1401
1402                 if ((sbi->s_qf_names[USRQUOTA] &&
1403                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1404                     (sbi->s_qf_names[GRPQUOTA] &&
1405                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1406                         printk(KERN_ERR "EXT4-fs: old and new quota "
1407                                         "format mixing.\n");
1408                         return 0;
1409                 }
1410
1411                 if (!sbi->s_jquota_fmt) {
1412                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1413                                         "not specified.\n");
1414                         return 0;
1415                 }
1416         } else {
1417                 if (sbi->s_jquota_fmt) {
1418                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1419                                         "specified with no journaling "
1420                                         "enabled.\n");
1421                         return 0;
1422                 }
1423         }
1424 #endif
1425         return 1;
1426 }
1427
1428 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1429                             int read_only)
1430 {
1431         struct ext4_sb_info *sbi = EXT4_SB(sb);
1432         int res = 0;
1433
1434         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1435                 printk(KERN_ERR "EXT4-fs warning: revision level too high, "
1436                        "forcing read-only mode\n");
1437                 res = MS_RDONLY;
1438         }
1439         if (read_only)
1440                 return res;
1441         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1442                 printk(KERN_WARNING "EXT4-fs warning: mounting unchecked fs, "
1443                        "running e2fsck is recommended\n");
1444         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1445                 printk(KERN_WARNING
1446                        "EXT4-fs warning: mounting fs with errors, "
1447                        "running e2fsck is recommended\n");
1448         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1449                  le16_to_cpu(es->s_mnt_count) >=
1450                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1451                 printk(KERN_WARNING
1452                        "EXT4-fs warning: maximal mount count reached, "
1453                        "running e2fsck is recommended\n");
1454         else if (le32_to_cpu(es->s_checkinterval) &&
1455                 (le32_to_cpu(es->s_lastcheck) +
1456                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1457                 printk(KERN_WARNING
1458                        "EXT4-fs warning: checktime reached, "
1459                        "running e2fsck is recommended\n");
1460 #if 0
1461                 /* @@@ We _will_ want to clear the valid bit if we find
1462                  * inconsistencies, to force a fsck at reboot.  But for
1463                  * a plain journaled filesystem we can keep it set as
1464                  * valid forever! :)
1465                  */
1466         es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1467 #endif
1468         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1469                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1470         le16_add_cpu(&es->s_mnt_count, 1);
1471         es->s_mtime = cpu_to_le32(get_seconds());
1472         ext4_update_dynamic_rev(sb);
1473         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1474
1475         ext4_commit_super(sb, es, 1);
1476         if (test_opt(sb, DEBUG))
1477                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%lu, "
1478                                 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
1479                         sb->s_blocksize,
1480                         sbi->s_groups_count,
1481                         EXT4_BLOCKS_PER_GROUP(sb),
1482                         EXT4_INODES_PER_GROUP(sb),
1483                         sbi->s_mount_opt);
1484
1485         printk(KERN_INFO "EXT4 FS on %s, %s journal on %s\n",
1486                sb->s_id, EXT4_SB(sb)->s_journal->j_inode ? "internal" :
1487                "external", EXT4_SB(sb)->s_journal->j_devname);
1488         return res;
1489 }
1490
1491 static int ext4_fill_flex_info(struct super_block *sb)
1492 {
1493         struct ext4_sb_info *sbi = EXT4_SB(sb);
1494         struct ext4_group_desc *gdp = NULL;
1495         struct buffer_head *bh;
1496         ext4_group_t flex_group_count;
1497         ext4_group_t flex_group;
1498         int groups_per_flex = 0;
1499         __u64 block_bitmap = 0;
1500         int i;
1501
1502         if (!sbi->s_es->s_log_groups_per_flex) {
1503                 sbi->s_log_groups_per_flex = 0;
1504                 return 1;
1505         }
1506
1507         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1508         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1509
1510         /* We allocate both existing and potentially added groups */
1511         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1512                             ((sbi->s_es->s_reserved_gdt_blocks +1 ) <<
1513                               EXT4_DESC_PER_BLOCK_BITS(sb))) /
1514                            groups_per_flex;
1515         sbi->s_flex_groups = kzalloc(flex_group_count *
1516                                      sizeof(struct flex_groups), GFP_KERNEL);
1517         if (sbi->s_flex_groups == NULL) {
1518                 printk(KERN_ERR "EXT4-fs: not enough memory for "
1519                                 "%lu flex groups\n", flex_group_count);
1520                 goto failed;
1521         }
1522
1523         gdp = ext4_get_group_desc(sb, 1, &bh);
1524         block_bitmap = ext4_block_bitmap(sb, gdp) - 1;
1525
1526         for (i = 0; i < sbi->s_groups_count; i++) {
1527                 gdp = ext4_get_group_desc(sb, i, &bh);
1528
1529                 flex_group = ext4_flex_group(sbi, i);
1530                 sbi->s_flex_groups[flex_group].free_inodes +=
1531                         le16_to_cpu(gdp->bg_free_inodes_count);
1532                 sbi->s_flex_groups[flex_group].free_blocks +=
1533                         le16_to_cpu(gdp->bg_free_blocks_count);
1534         }
1535
1536         return 1;
1537 failed:
1538         return 0;
1539 }
1540
1541 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1542                             struct ext4_group_desc *gdp)
1543 {
1544         __u16 crc = 0;
1545
1546         if (sbi->s_es->s_feature_ro_compat &
1547             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1548                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1549                 __le32 le_group = cpu_to_le32(block_group);
1550
1551                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1552                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1553                 crc = crc16(crc, (__u8 *)gdp, offset);
1554                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1555                 /* for checksum of struct ext4_group_desc do the rest...*/
1556                 if ((sbi->s_es->s_feature_incompat &
1557                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1558                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1559                         crc = crc16(crc, (__u8 *)gdp + offset,
1560                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1561                                         offset);
1562         }
1563
1564         return cpu_to_le16(crc);
1565 }
1566
1567 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1568                                 struct ext4_group_desc *gdp)
1569 {
1570         if ((sbi->s_es->s_feature_ro_compat &
1571              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1572             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1573                 return 0;
1574
1575         return 1;
1576 }
1577
1578 /* Called at mount-time, super-block is locked */
1579 static int ext4_check_descriptors(struct super_block *sb)
1580 {
1581         struct ext4_sb_info *sbi = EXT4_SB(sb);
1582         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1583         ext4_fsblk_t last_block;
1584         ext4_fsblk_t block_bitmap;
1585         ext4_fsblk_t inode_bitmap;
1586         ext4_fsblk_t inode_table;
1587         int flexbg_flag = 0;
1588         ext4_group_t i;
1589
1590         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1591                 flexbg_flag = 1;
1592
1593         ext4_debug("Checking group descriptors");
1594
1595         for (i = 0; i < sbi->s_groups_count; i++) {
1596                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1597
1598                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1599                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1600                 else
1601                         last_block = first_block +
1602                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1603
1604                 block_bitmap = ext4_block_bitmap(sb, gdp);
1605                 if (block_bitmap < first_block || block_bitmap > last_block) {
1606                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1607                                "Block bitmap for group %lu not in group "
1608                                "(block %llu)!", i, block_bitmap);
1609                         return 0;
1610                 }
1611                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1612                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1613                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1614                                "Inode bitmap for group %lu not in group "
1615                                "(block %llu)!", i, inode_bitmap);
1616                         return 0;
1617                 }
1618                 inode_table = ext4_inode_table(sb, gdp);
1619                 if (inode_table < first_block ||
1620                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1621                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1622                                "Inode table for group %lu not in group "
1623                                "(block %llu)!", i, inode_table);
1624                         return 0;
1625                 }
1626                 spin_lock(sb_bgl_lock(sbi, i));
1627                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1628                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1629                                "Checksum for group %lu failed (%u!=%u)\n",
1630                                i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1631                                gdp)), le16_to_cpu(gdp->bg_checksum));
1632                         if (!(sb->s_flags & MS_RDONLY)) {
1633                                 spin_unlock(sb_bgl_lock(sbi, i));
1634                                 return 0;
1635                         }
1636                 }
1637                 spin_unlock(sb_bgl_lock(sbi, i));
1638                 if (!flexbg_flag)
1639                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1640         }
1641
1642         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1643         sbi->s_es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
1644         return 1;
1645 }
1646
1647 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1648  * the superblock) which were deleted from all directories, but held open by
1649  * a process at the time of a crash.  We walk the list and try to delete these
1650  * inodes at recovery time (only with a read-write filesystem).
1651  *
1652  * In order to keep the orphan inode chain consistent during traversal (in
1653  * case of crash during recovery), we link each inode into the superblock
1654  * orphan list_head and handle it the same way as an inode deletion during
1655  * normal operation (which journals the operations for us).
1656  *
1657  * We only do an iget() and an iput() on each inode, which is very safe if we
1658  * accidentally point at an in-use or already deleted inode.  The worst that
1659  * can happen in this case is that we get a "bit already cleared" message from
1660  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1661  * e2fsck was run on this filesystem, and it must have already done the orphan
1662  * inode cleanup for us, so we can safely abort without any further action.
1663  */
1664 static void ext4_orphan_cleanup(struct super_block *sb,
1665                                 struct ext4_super_block *es)
1666 {
1667         unsigned int s_flags = sb->s_flags;
1668         int nr_orphans = 0, nr_truncates = 0;
1669 #ifdef CONFIG_QUOTA
1670         int i;
1671 #endif
1672         if (!es->s_last_orphan) {
1673                 jbd_debug(4, "no orphan inodes to clean up\n");
1674                 return;
1675         }
1676
1677         if (bdev_read_only(sb->s_bdev)) {
1678                 printk(KERN_ERR "EXT4-fs: write access "
1679                         "unavailable, skipping orphan cleanup.\n");
1680                 return;
1681         }
1682
1683         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1684                 if (es->s_last_orphan)
1685                         jbd_debug(1, "Errors on filesystem, "
1686                                   "clearing orphan list.\n");
1687                 es->s_last_orphan = 0;
1688                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1689                 return;
1690         }
1691
1692         if (s_flags & MS_RDONLY) {
1693                 printk(KERN_INFO "EXT4-fs: %s: orphan cleanup on readonly fs\n",
1694                        sb->s_id);
1695                 sb->s_flags &= ~MS_RDONLY;
1696         }
1697 #ifdef CONFIG_QUOTA
1698         /* Needed for iput() to work correctly and not trash data */
1699         sb->s_flags |= MS_ACTIVE;
1700         /* Turn on quotas so that they are updated correctly */
1701         for (i = 0; i < MAXQUOTAS; i++) {
1702                 if (EXT4_SB(sb)->s_qf_names[i]) {
1703                         int ret = ext4_quota_on_mount(sb, i);
1704                         if (ret < 0)
1705                                 printk(KERN_ERR
1706                                         "EXT4-fs: Cannot turn on journaled "
1707                                         "quota: error %d\n", ret);
1708                 }
1709         }
1710 #endif
1711
1712         while (es->s_last_orphan) {
1713                 struct inode *inode;
1714
1715                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1716                 if (IS_ERR(inode)) {
1717                         es->s_last_orphan = 0;
1718                         break;
1719                 }
1720
1721                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1722                 DQUOT_INIT(inode);
1723                 if (inode->i_nlink) {
1724                         printk(KERN_DEBUG
1725                                 "%s: truncating inode %lu to %lld bytes\n",
1726                                 __func__, inode->i_ino, inode->i_size);
1727                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1728                                   inode->i_ino, inode->i_size);
1729                         ext4_truncate(inode);
1730                         nr_truncates++;
1731                 } else {
1732                         printk(KERN_DEBUG
1733                                 "%s: deleting unreferenced inode %lu\n",
1734                                 __func__, inode->i_ino);
1735                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1736                                   inode->i_ino);
1737                         nr_orphans++;
1738                 }
1739                 iput(inode);  /* The delete magic happens here! */
1740         }
1741
1742 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1743
1744         if (nr_orphans)
1745                 printk(KERN_INFO "EXT4-fs: %s: %d orphan inode%s deleted\n",
1746                        sb->s_id, PLURAL(nr_orphans));
1747         if (nr_truncates)
1748                 printk(KERN_INFO "EXT4-fs: %s: %d truncate%s cleaned up\n",
1749                        sb->s_id, PLURAL(nr_truncates));
1750 #ifdef CONFIG_QUOTA
1751         /* Turn quotas off */
1752         for (i = 0; i < MAXQUOTAS; i++) {
1753                 if (sb_dqopt(sb)->files[i])
1754                         vfs_quota_off(sb, i, 0);
1755         }
1756 #endif
1757         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1758 }
1759 /*
1760  * Maximal extent format file size.
1761  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1762  * extent format containers, within a sector_t, and within i_blocks
1763  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1764  * so that won't be a limiting factor.
1765  *
1766  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1767  */
1768 static loff_t ext4_max_size(int blkbits)
1769 {
1770         loff_t res;
1771         loff_t upper_limit = MAX_LFS_FILESIZE;
1772
1773         /* small i_blocks in vfs inode? */
1774         if (sizeof(blkcnt_t) < sizeof(u64)) {
1775                 /*
1776                  * CONFIG_LSF is not enabled implies the inode
1777                  * i_block represent total blocks in 512 bytes
1778                  * 32 == size of vfs inode i_blocks * 8
1779                  */
1780                 upper_limit = (1LL << 32) - 1;
1781
1782                 /* total blocks in file system block size */
1783                 upper_limit >>= (blkbits - 9);
1784                 upper_limit <<= blkbits;
1785         }
1786
1787         /* 32-bit extent-start container, ee_block */
1788         res = 1LL << 32;
1789         res <<= blkbits;
1790         res -= 1;
1791
1792         /* Sanity check against vm- & vfs- imposed limits */
1793         if (res > upper_limit)
1794                 res = upper_limit;
1795
1796         return res;
1797 }
1798
1799 /*
1800  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
1801  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
1802  * We need to be 1 filesystem block less than the 2^48 sector limit.
1803  */
1804 static loff_t ext4_max_bitmap_size(int bits)
1805 {
1806         loff_t res = EXT4_NDIR_BLOCKS;
1807         int meta_blocks;
1808         loff_t upper_limit;
1809         /* This is calculated to be the largest file size for a
1810          * dense, bitmapped file such that the total number of
1811          * sectors in the file, including data and all indirect blocks,
1812          * does not exceed 2^48 -1
1813          * __u32 i_blocks_lo and _u16 i_blocks_high representing the
1814          * total number of  512 bytes blocks of the file
1815          */
1816
1817         if (sizeof(blkcnt_t) < sizeof(u64)) {
1818                 /*
1819                  * CONFIG_LSF is not enabled implies the inode
1820                  * i_block represent total blocks in 512 bytes
1821                  * 32 == size of vfs inode i_blocks * 8
1822                  */
1823                 upper_limit = (1LL << 32) - 1;
1824
1825                 /* total blocks in file system block size */
1826                 upper_limit >>= (bits - 9);
1827
1828         } else {
1829                 /*
1830                  * We use 48 bit ext4_inode i_blocks
1831                  * With EXT4_HUGE_FILE_FL set the i_blocks
1832                  * represent total number of blocks in
1833                  * file system block size
1834                  */
1835                 upper_limit = (1LL << 48) - 1;
1836
1837         }
1838
1839         /* indirect blocks */
1840         meta_blocks = 1;
1841         /* double indirect blocks */
1842         meta_blocks += 1 + (1LL << (bits-2));
1843         /* tripple indirect blocks */
1844         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
1845
1846         upper_limit -= meta_blocks;
1847         upper_limit <<= bits;
1848
1849         res += 1LL << (bits-2);
1850         res += 1LL << (2*(bits-2));
1851         res += 1LL << (3*(bits-2));
1852         res <<= bits;
1853         if (res > upper_limit)
1854                 res = upper_limit;
1855
1856         if (res > MAX_LFS_FILESIZE)
1857                 res = MAX_LFS_FILESIZE;
1858
1859         return res;
1860 }
1861
1862 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
1863                                 ext4_fsblk_t logical_sb_block, int nr)
1864 {
1865         struct ext4_sb_info *sbi = EXT4_SB(sb);
1866         ext4_group_t bg, first_meta_bg;
1867         int has_super = 0;
1868
1869         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
1870
1871         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
1872             nr < first_meta_bg)
1873                 return logical_sb_block + nr + 1;
1874         bg = sbi->s_desc_per_block * nr;
1875         if (ext4_bg_has_super(sb, bg))
1876                 has_super = 1;
1877         return (has_super + ext4_group_first_block_no(sb, bg));
1878 }
1879
1880 /**
1881  * ext4_get_stripe_size: Get the stripe size.
1882  * @sbi: In memory super block info
1883  *
1884  * If we have specified it via mount option, then
1885  * use the mount option value. If the value specified at mount time is
1886  * greater than the blocks per group use the super block value.
1887  * If the super block value is greater than blocks per group return 0.
1888  * Allocator needs it be less than blocks per group.
1889  *
1890  */
1891 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
1892 {
1893         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
1894         unsigned long stripe_width =
1895                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
1896
1897         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
1898                 return sbi->s_stripe;
1899
1900         if (stripe_width <= sbi->s_blocks_per_group)
1901                 return stripe_width;
1902
1903         if (stride <= sbi->s_blocks_per_group)
1904                 return stride;
1905
1906         return 0;
1907 }
1908
1909 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
1910                                 __releases(kernel_lock)
1911                                 __acquires(kernel_lock)
1912
1913 {
1914         struct buffer_head *bh;
1915         struct ext4_super_block *es = NULL;
1916         struct ext4_sb_info *sbi;
1917         ext4_fsblk_t block;
1918         ext4_fsblk_t sb_block = get_sb_block(&data);
1919         ext4_fsblk_t logical_sb_block;
1920         unsigned long offset = 0;
1921         unsigned int journal_inum = 0;
1922         unsigned long journal_devnum = 0;
1923         unsigned long def_mount_opts;
1924         struct inode *root;
1925         char *cp;
1926         int ret = -EINVAL;
1927         int blocksize;
1928         int db_count;
1929         int i;
1930         int needs_recovery;
1931         __le32 features;
1932         __u64 blocks_count;
1933         int err;
1934
1935         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
1936         if (!sbi)
1937                 return -ENOMEM;
1938         sb->s_fs_info = sbi;
1939         sbi->s_mount_opt = 0;
1940         sbi->s_resuid = EXT4_DEF_RESUID;
1941         sbi->s_resgid = EXT4_DEF_RESGID;
1942         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
1943         sbi->s_sb_block = sb_block;
1944
1945         unlock_kernel();
1946
1947         /* Cleanup superblock name */
1948         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
1949                 *cp = '!';
1950
1951         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
1952         if (!blocksize) {
1953                 printk(KERN_ERR "EXT4-fs: unable to set blocksize\n");
1954                 goto out_fail;
1955         }
1956
1957         /*
1958          * The ext4 superblock will not be buffer aligned for other than 1kB
1959          * block sizes.  We need to calculate the offset from buffer start.
1960          */
1961         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
1962                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
1963                 offset = do_div(logical_sb_block, blocksize);
1964         } else {
1965                 logical_sb_block = sb_block;
1966         }
1967
1968         if (!(bh = sb_bread(sb, logical_sb_block))) {
1969                 printk(KERN_ERR "EXT4-fs: unable to read superblock\n");
1970                 goto out_fail;
1971         }
1972         /*
1973          * Note: s_es must be initialized as soon as possible because
1974          *       some ext4 macro-instructions depend on its value
1975          */
1976         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
1977         sbi->s_es = es;
1978         sb->s_magic = le16_to_cpu(es->s_magic);
1979         if (sb->s_magic != EXT4_SUPER_MAGIC)
1980                 goto cantfind_ext4;
1981
1982         /* Set defaults before we parse the mount options */
1983         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
1984         if (def_mount_opts & EXT4_DEFM_DEBUG)
1985                 set_opt(sbi->s_mount_opt, DEBUG);
1986         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
1987                 set_opt(sbi->s_mount_opt, GRPID);
1988         if (def_mount_opts & EXT4_DEFM_UID16)
1989                 set_opt(sbi->s_mount_opt, NO_UID32);
1990 #ifdef CONFIG_EXT4_FS_XATTR
1991         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
1992                 set_opt(sbi->s_mount_opt, XATTR_USER);
1993 #endif
1994 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1995         if (def_mount_opts & EXT4_DEFM_ACL)
1996                 set_opt(sbi->s_mount_opt, POSIX_ACL);
1997 #endif
1998         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
1999                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
2000         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2001                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
2002         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2003                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2004
2005         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2006                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2007         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2008                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2009         else
2010                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2011
2012         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2013         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2014
2015         set_opt(sbi->s_mount_opt, RESERVATION);
2016         set_opt(sbi->s_mount_opt, BARRIER);
2017
2018         /*
2019          * turn on extents feature by default in ext4 filesystem
2020          * only if feature flag already set by mkfs or tune2fs.
2021          * Use -o noextents to turn it off
2022          */
2023         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
2024                 set_opt(sbi->s_mount_opt, EXTENTS);
2025         else
2026                 ext4_warning(sb, __func__,
2027                         "extents feature not enabled on this filesystem, "
2028                         "use tune2fs.\n");
2029
2030         /*
2031          * enable delayed allocation by default
2032          * Use -o nodelalloc to turn it off
2033          */
2034         set_opt(sbi->s_mount_opt, DELALLOC);
2035
2036
2037         if (!parse_options((char *) data, sb, &journal_inum, &journal_devnum,
2038                            NULL, 0))
2039                 goto failed_mount;
2040
2041         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2042                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2043
2044         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2045             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2046              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2047              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2048                 printk(KERN_WARNING
2049                        "EXT4-fs warning: feature flags set on rev 0 fs, "
2050                        "running e2fsck is recommended\n");
2051
2052         /*
2053          * Check feature flags regardless of the revision level, since we
2054          * previously didn't change the revision level when setting the flags,
2055          * so there is a chance incompat flags are set on a rev 0 filesystem.
2056          */
2057         features = EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP);
2058         if (features) {
2059                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount because of "
2060                        "unsupported optional features (%x).\n",
2061                        sb->s_id, le32_to_cpu(features));
2062                 goto failed_mount;
2063         }
2064         features = EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP);
2065         if (!(sb->s_flags & MS_RDONLY) && features) {
2066                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount RDWR because of "
2067                        "unsupported optional features (%x).\n",
2068                        sb->s_id, le32_to_cpu(features));
2069                 goto failed_mount;
2070         }
2071         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2072                 /*
2073                  * Large file size enabled file system can only be
2074                  * mount if kernel is build with CONFIG_LSF
2075                  */
2076                 if (sizeof(root->i_blocks) < sizeof(u64) &&
2077                                 !(sb->s_flags & MS_RDONLY)) {
2078                         printk(KERN_ERR "EXT4-fs: %s: Filesystem with huge "
2079                                         "files cannot be mounted read-write "
2080                                         "without CONFIG_LSF.\n", sb->s_id);
2081                         goto failed_mount;
2082                 }
2083         }
2084         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2085
2086         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2087             blocksize > EXT4_MAX_BLOCK_SIZE) {
2088                 printk(KERN_ERR
2089                        "EXT4-fs: Unsupported filesystem blocksize %d on %s.\n",
2090                        blocksize, sb->s_id);
2091                 goto failed_mount;
2092         }
2093
2094         if (sb->s_blocksize != blocksize) {
2095
2096                 /* Validate the filesystem blocksize */
2097                 if (!sb_set_blocksize(sb, blocksize)) {
2098                         printk(KERN_ERR "EXT4-fs: bad block size %d.\n",
2099                                         blocksize);
2100                         goto failed_mount;
2101                 }
2102
2103                 brelse(bh);
2104                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2105                 offset = do_div(logical_sb_block, blocksize);
2106                 bh = sb_bread(sb, logical_sb_block);
2107                 if (!bh) {
2108                         printk(KERN_ERR
2109                                "EXT4-fs: Can't read superblock on 2nd try.\n");
2110                         goto failed_mount;
2111                 }
2112                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2113                 sbi->s_es = es;
2114                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2115                         printk(KERN_ERR
2116                                "EXT4-fs: Magic mismatch, very weird !\n");
2117                         goto failed_mount;
2118                 }
2119         }
2120
2121         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits);
2122         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits);
2123
2124         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2125                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2126                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2127         } else {
2128                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2129                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2130                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2131                     (!is_power_of_2(sbi->s_inode_size)) ||
2132                     (sbi->s_inode_size > blocksize)) {
2133                         printk(KERN_ERR
2134                                "EXT4-fs: unsupported inode size: %d\n",
2135                                sbi->s_inode_size);
2136                         goto failed_mount;
2137                 }
2138                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2139                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2140         }
2141         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2142         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2143                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2144                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2145                     !is_power_of_2(sbi->s_desc_size)) {
2146                         printk(KERN_ERR
2147                                "EXT4-fs: unsupported descriptor size %lu\n",
2148                                sbi->s_desc_size);
2149                         goto failed_mount;
2150                 }
2151         } else
2152                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2153         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2154         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2155         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2156                 goto cantfind_ext4;
2157         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2158         if (sbi->s_inodes_per_block == 0)
2159                 goto cantfind_ext4;
2160         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2161                                         sbi->s_inodes_per_block;
2162         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2163         sbi->s_sbh = bh;
2164         sbi->s_mount_state = le16_to_cpu(es->s_state);
2165         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2166         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2167         for (i = 0; i < 4; i++)
2168                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2169         sbi->s_def_hash_version = es->s_def_hash_version;
2170
2171         if (sbi->s_blocks_per_group > blocksize * 8) {
2172                 printk(KERN_ERR
2173                        "EXT4-fs: #blocks per group too big: %lu\n",
2174                        sbi->s_blocks_per_group);
2175                 goto failed_mount;
2176         }
2177         if (sbi->s_inodes_per_group > blocksize * 8) {
2178                 printk(KERN_ERR
2179                        "EXT4-fs: #inodes per group too big: %lu\n",
2180                        sbi->s_inodes_per_group);
2181                 goto failed_mount;
2182         }
2183
2184         if (ext4_blocks_count(es) >
2185                     (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
2186                 printk(KERN_ERR "EXT4-fs: filesystem on %s:"
2187                         " too large to mount safely\n", sb->s_id);
2188                 if (sizeof(sector_t) < 8)
2189                         printk(KERN_WARNING "EXT4-fs: CONFIG_LBD not "
2190                                         "enabled\n");
2191                 goto failed_mount;
2192         }
2193
2194         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2195                 goto cantfind_ext4;
2196
2197         /* ensure blocks_count calculation below doesn't sign-extend */
2198         if (ext4_blocks_count(es) + EXT4_BLOCKS_PER_GROUP(sb) <
2199             le32_to_cpu(es->s_first_data_block) + 1) {
2200                 printk(KERN_WARNING "EXT4-fs: bad geometry: block count %llu, "
2201                        "first data block %u, blocks per group %lu\n",
2202                         ext4_blocks_count(es),
2203                         le32_to_cpu(es->s_first_data_block),
2204                         EXT4_BLOCKS_PER_GROUP(sb));
2205                 goto failed_mount;
2206         }
2207         blocks_count = (ext4_blocks_count(es) -
2208                         le32_to_cpu(es->s_first_data_block) +
2209                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2210         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2211         sbi->s_groups_count = blocks_count;
2212         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2213                    EXT4_DESC_PER_BLOCK(sb);
2214         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2215                                     GFP_KERNEL);
2216         if (sbi->s_group_desc == NULL) {
2217                 printk(KERN_ERR "EXT4-fs: not enough memory\n");
2218                 goto failed_mount;
2219         }
2220
2221         if (ext4_proc_root)
2222                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2223
2224         if (sbi->s_proc)
2225                 proc_create_data("inode_readahead_blks", 0644, sbi->s_proc,
2226                                  &ext4_ui_proc_fops,
2227                                  &sbi->s_inode_readahead_blks);
2228
2229         bgl_lock_init(&sbi->s_blockgroup_lock);
2230
2231         for (i = 0; i < db_count; i++) {
2232                 block = descriptor_loc(sb, logical_sb_block, i);
2233                 sbi->s_group_desc[i] = sb_bread(sb, block);
2234                 if (!sbi->s_group_desc[i]) {
2235                         printk(KERN_ERR "EXT4-fs: "
2236                                "can't read group descriptor %d\n", i);
2237                         db_count = i;
2238                         goto failed_mount2;
2239                 }
2240         }
2241         if (!ext4_check_descriptors(sb)) {
2242                 printk(KERN_ERR "EXT4-fs: group descriptors corrupted!\n");
2243                 goto failed_mount2;
2244         }
2245         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2246                 if (!ext4_fill_flex_info(sb)) {
2247                         printk(KERN_ERR
2248                                "EXT4-fs: unable to initialize "
2249                                "flex_bg meta info!\n");
2250                         goto failed_mount2;
2251                 }
2252
2253         sbi->s_gdb_count = db_count;
2254         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2255         spin_lock_init(&sbi->s_next_gen_lock);
2256
2257         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2258                         ext4_count_free_blocks(sb));
2259         if (!err) {
2260                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2261                                 ext4_count_free_inodes(sb));
2262         }
2263         if (!err) {
2264                 err = percpu_counter_init(&sbi->s_dirs_counter,
2265                                 ext4_count_dirs(sb));
2266         }
2267         if (!err) {
2268                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2269         }
2270         if (err) {
2271                 printk(KERN_ERR "EXT4-fs: insufficient memory\n");
2272                 goto failed_mount3;
2273         }
2274
2275         sbi->s_stripe = ext4_get_stripe_size(sbi);
2276
2277         /*
2278          * set up enough so that it can read an inode
2279          */
2280         sb->s_op = &ext4_sops;
2281         sb->s_export_op = &ext4_export_ops;
2282         sb->s_xattr = ext4_xattr_handlers;
2283 #ifdef CONFIG_QUOTA
2284         sb->s_qcop = &ext4_qctl_operations;
2285         sb->dq_op = &ext4_quota_operations;
2286 #endif
2287         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2288
2289         sb->s_root = NULL;
2290
2291         needs_recovery = (es->s_last_orphan != 0 ||
2292                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2293                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2294
2295         /*
2296          * The first inode we look at is the journal inode.  Don't try
2297          * root first: it may be modified in the journal!
2298          */
2299         if (!test_opt(sb, NOLOAD) &&
2300             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2301                 if (ext4_load_journal(sb, es, journal_devnum))
2302                         goto failed_mount3;
2303                 if (!(sb->s_flags & MS_RDONLY) &&
2304                     EXT4_SB(sb)->s_journal->j_failed_commit) {
2305                         printk(KERN_CRIT "EXT4-fs error (device %s): "
2306                                "ext4_fill_super: Journal transaction "
2307                                "%u is corrupt\n", sb->s_id,
2308                                EXT4_SB(sb)->s_journal->j_failed_commit);
2309                         if (test_opt(sb, ERRORS_RO)) {
2310                                 printk(KERN_CRIT
2311                                        "Mounting filesystem read-only\n");
2312                                 sb->s_flags |= MS_RDONLY;
2313                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2314                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2315                         }
2316                         if (test_opt(sb, ERRORS_PANIC)) {
2317                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2318                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2319                                 ext4_commit_super(sb, es, 1);
2320                                 printk(KERN_CRIT
2321                                        "EXT4-fs (device %s): mount failed\n",
2322                                       sb->s_id);
2323                                 goto failed_mount4;
2324                         }
2325                 }
2326         } else if (journal_inum) {
2327                 if (ext4_create_journal(sb, es, journal_inum))
2328                         goto failed_mount3;
2329         } else {
2330                 if (!silent)
2331                         printk(KERN_ERR
2332                                "ext4: No journal on filesystem on %s\n",
2333                                sb->s_id);
2334                 goto failed_mount3;
2335         }
2336
2337         if (ext4_blocks_count(es) > 0xffffffffULL &&
2338             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2339                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2340                 printk(KERN_ERR "ext4: Failed to set 64-bit journal feature\n");
2341                 goto failed_mount4;
2342         }
2343
2344         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2345                 jbd2_journal_set_features(sbi->s_journal,
2346                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2347                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2348         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2349                 jbd2_journal_set_features(sbi->s_journal,
2350                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2351                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2352                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2353         } else {
2354                 jbd2_journal_clear_features(sbi->s_journal,
2355                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2356                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2357         }
2358
2359         /* We have now updated the journal if required, so we can
2360          * validate the data journaling mode. */
2361         switch (test_opt(sb, DATA_FLAGS)) {
2362         case 0:
2363                 /* No mode set, assume a default based on the journal
2364                  * capabilities: ORDERED_DATA if the journal can
2365                  * cope, else JOURNAL_DATA
2366                  */
2367                 if (jbd2_journal_check_available_features
2368                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2369                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2370                 else
2371                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2372                 break;
2373
2374         case EXT4_MOUNT_ORDERED_DATA:
2375         case EXT4_MOUNT_WRITEBACK_DATA:
2376                 if (!jbd2_journal_check_available_features
2377                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2378                         printk(KERN_ERR "EXT4-fs: Journal does not support "
2379                                "requested data journaling mode\n");
2380                         goto failed_mount4;
2381                 }
2382         default:
2383                 break;
2384         }
2385
2386         if (test_opt(sb, NOBH)) {
2387                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2388                         printk(KERN_WARNING "EXT4-fs: Ignoring nobh option - "
2389                                 "its supported only with writeback mode\n");
2390                         clear_opt(sbi->s_mount_opt, NOBH);
2391                 }
2392         }
2393         /*
2394          * The jbd2_journal_load will have done any necessary log recovery,
2395          * so we can safely mount the rest of the filesystem now.
2396          */
2397
2398         root = ext4_iget(sb, EXT4_ROOT_INO);
2399         if (IS_ERR(root)) {
2400                 printk(KERN_ERR "EXT4-fs: get root inode failed\n");
2401                 ret = PTR_ERR(root);
2402                 goto failed_mount4;
2403         }
2404         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2405                 iput(root);
2406                 printk(KERN_ERR "EXT4-fs: corrupt root inode, run e2fsck\n");
2407                 goto failed_mount4;
2408         }
2409         sb->s_root = d_alloc_root(root);
2410         if (!sb->s_root) {
2411                 printk(KERN_ERR "EXT4-fs: get root dentry failed\n");
2412                 iput(root);
2413                 ret = -ENOMEM;
2414                 goto failed_mount4;
2415         }
2416
2417         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2418
2419         /* determine the minimum size of new large inodes, if present */
2420         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2421                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2422                                                      EXT4_GOOD_OLD_INODE_SIZE;
2423                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2424                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2425                         if (sbi->s_want_extra_isize <
2426                             le16_to_cpu(es->s_want_extra_isize))
2427                                 sbi->s_want_extra_isize =
2428                                         le16_to_cpu(es->s_want_extra_isize);
2429                         if (sbi->s_want_extra_isize <
2430                             le16_to_cpu(es->s_min_extra_isize))
2431                                 sbi->s_want_extra_isize =
2432                                         le16_to_cpu(es->s_min_extra_isize);
2433                 }
2434         }
2435         /* Check if enough inode space is available */
2436         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2437                                                         sbi->s_inode_size) {
2438                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2439                                                        EXT4_GOOD_OLD_INODE_SIZE;
2440                 printk(KERN_INFO "EXT4-fs: required extra inode space not"
2441                         "available.\n");
2442         }
2443
2444         /*
2445          * akpm: core read_super() calls in here with the superblock locked.
2446          * That deadlocks, because orphan cleanup needs to lock the superblock
2447          * in numerous places.  Here we just pop the lock - it's relatively
2448          * harmless, because we are now ready to accept write_super() requests,
2449          * and aviro says that's the only reason for hanging onto the
2450          * superblock lock.
2451          */
2452         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2453         ext4_orphan_cleanup(sb, es);
2454         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2455         if (needs_recovery)
2456                 printk(KERN_INFO "EXT4-fs: recovery complete.\n");
2457         ext4_mark_recovery_complete(sb, es);
2458         printk(KERN_INFO "EXT4-fs: mounted filesystem with %s data mode.\n",
2459                test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ? "journal":
2460                test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA ? "ordered":
2461                "writeback");
2462
2463         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
2464                 printk(KERN_WARNING "EXT4-fs: Ignoring delalloc option - "
2465                                 "requested data journaling mode\n");
2466                 clear_opt(sbi->s_mount_opt, DELALLOC);
2467         } else if (test_opt(sb, DELALLOC))
2468                 printk(KERN_INFO "EXT4-fs: delayed allocation enabled\n");
2469
2470         ext4_ext_init(sb);
2471         err = ext4_mb_init(sb, needs_recovery);
2472         if (err) {
2473                 printk(KERN_ERR "EXT4-fs: failed to initalize mballoc (%d)\n",
2474                        err);
2475                 goto failed_mount4;
2476         }
2477
2478         lock_kernel();
2479         return 0;
2480
2481 cantfind_ext4:
2482         if (!silent)
2483                 printk(KERN_ERR "VFS: Can't find ext4 filesystem on dev %s.\n",
2484                        sb->s_id);
2485         goto failed_mount;
2486
2487 failed_mount4:
2488         jbd2_journal_destroy(sbi->s_journal);
2489         sbi->s_journal = NULL;
2490 failed_mount3:
2491         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2492         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2493         percpu_counter_destroy(&sbi->s_dirs_counter);
2494         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2495 failed_mount2:
2496         for (i = 0; i < db_count; i++)
2497                 brelse(sbi->s_group_desc[i]);
2498         kfree(sbi->s_group_desc);
2499 failed_mount:
2500         if (sbi->s_proc) {
2501                 remove_proc_entry("inode_readahead_blks", sbi->s_proc);
2502                 remove_proc_entry(sb->s_id, ext4_proc_root);
2503         }
2504 #ifdef CONFIG_QUOTA
2505         for (i = 0; i < MAXQUOTAS; i++)
2506                 kfree(sbi->s_qf_names[i]);
2507 #endif
2508         ext4_blkdev_remove(sbi);
2509         brelse(bh);
2510 out_fail:
2511         sb->s_fs_info = NULL;
2512         kfree(sbi);
2513         lock_kernel();
2514         return ret;
2515 }
2516
2517 /*
2518  * Setup any per-fs journal parameters now.  We'll do this both on
2519  * initial mount, once the journal has been initialised but before we've
2520  * done any recovery; and again on any subsequent remount.
2521  */
2522 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2523 {
2524         struct ext4_sb_info *sbi = EXT4_SB(sb);
2525
2526         if (sbi->s_commit_interval)
2527                 journal->j_commit_interval = sbi->s_commit_interval;
2528         /* We could also set up an ext4-specific default for the commit
2529          * interval here, but for now we'll just fall back to the jbd
2530          * default. */
2531
2532         spin_lock(&journal->j_state_lock);
2533         if (test_opt(sb, BARRIER))
2534                 journal->j_flags |= JBD2_BARRIER;
2535         else
2536                 journal->j_flags &= ~JBD2_BARRIER;
2537         spin_unlock(&journal->j_state_lock);
2538 }
2539
2540 static journal_t *ext4_get_journal(struct super_block *sb,
2541                                    unsigned int journal_inum)
2542 {
2543         struct inode *journal_inode;
2544         journal_t *journal;
2545
2546         /* First, test for the existence of a valid inode on disk.  Bad
2547          * things happen if we iget() an unused inode, as the subsequent
2548          * iput() will try to delete it. */
2549
2550         journal_inode = ext4_iget(sb, journal_inum);
2551         if (IS_ERR(journal_inode)) {
2552                 printk(KERN_ERR "EXT4-fs: no journal found.\n");
2553                 return NULL;
2554         }
2555         if (!journal_inode->i_nlink) {
2556                 make_bad_inode(journal_inode);
2557                 iput(journal_inode);
2558                 printk(KERN_ERR "EXT4-fs: journal inode is deleted.\n");
2559                 return NULL;
2560         }
2561
2562         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
2563                   journal_inode, journal_inode->i_size);
2564         if (!S_ISREG(journal_inode->i_mode)) {
2565                 printk(KERN_ERR "EXT4-fs: invalid journal inode.\n");
2566                 iput(journal_inode);
2567                 return NULL;
2568         }
2569
2570         journal = jbd2_journal_init_inode(journal_inode);
2571         if (!journal) {
2572                 printk(KERN_ERR "EXT4-fs: Could not load journal inode\n");
2573                 iput(journal_inode);
2574                 return NULL;
2575         }
2576         journal->j_private = sb;
2577         ext4_init_journal_params(sb, journal);
2578         return journal;
2579 }
2580
2581 static journal_t *ext4_get_dev_journal(struct super_block *sb,
2582                                        dev_t j_dev)
2583 {
2584         struct buffer_head *bh;
2585         journal_t *journal;
2586         ext4_fsblk_t start;
2587         ext4_fsblk_t len;
2588         int hblock, blocksize;
2589         ext4_fsblk_t sb_block;
2590         unsigned long offset;
2591         struct ext4_super_block *es;
2592         struct block_device *bdev;
2593
2594         bdev = ext4_blkdev_get(j_dev);
2595         if (bdev == NULL)
2596                 return NULL;
2597
2598         if (bd_claim(bdev, sb)) {
2599                 printk(KERN_ERR
2600                         "EXT4: failed to claim external journal device.\n");
2601                 blkdev_put(bdev);
2602                 return NULL;
2603         }
2604
2605         blocksize = sb->s_blocksize;
2606         hblock = bdev_hardsect_size(bdev);
2607         if (blocksize < hblock) {
2608                 printk(KERN_ERR
2609                         "EXT4-fs: blocksize too small for journal device.\n");
2610                 goto out_bdev;
2611         }
2612
2613         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
2614         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
2615         set_blocksize(bdev, blocksize);
2616         if (!(bh = __bread(bdev, sb_block, blocksize))) {
2617                 printk(KERN_ERR "EXT4-fs: couldn't read superblock of "
2618                        "external journal\n");
2619                 goto out_bdev;
2620         }
2621
2622         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2623         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
2624             !(le32_to_cpu(es->s_feature_incompat) &
2625               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
2626                 printk(KERN_ERR "EXT4-fs: external journal has "
2627                                         "bad superblock\n");
2628                 brelse(bh);
2629                 goto out_bdev;
2630         }
2631
2632         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
2633                 printk(KERN_ERR "EXT4-fs: journal UUID does not match\n");
2634                 brelse(bh);
2635                 goto out_bdev;
2636         }
2637
2638         len = ext4_blocks_count(es);
2639         start = sb_block + 1;
2640         brelse(bh);     /* we're done with the superblock */
2641
2642         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
2643                                         start, len, blocksize);
2644         if (!journal) {
2645                 printk(KERN_ERR "EXT4-fs: failed to create device journal\n");
2646                 goto out_bdev;
2647         }
2648         journal->j_private = sb;
2649         ll_rw_block(READ, 1, &journal->j_sb_buffer);
2650         wait_on_buffer(journal->j_sb_buffer);
2651         if (!buffer_uptodate(journal->j_sb_buffer)) {
2652                 printk(KERN_ERR "EXT4-fs: I/O error on journal device\n");
2653                 goto out_journal;
2654         }
2655         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
2656                 printk(KERN_ERR "EXT4-fs: External journal has more than one "
2657                                         "user (unsupported) - %d\n",
2658                         be32_to_cpu(journal->j_superblock->s_nr_users));
2659                 goto out_journal;
2660         }
2661         EXT4_SB(sb)->journal_bdev = bdev;
2662         ext4_init_journal_params(sb, journal);
2663         return journal;
2664 out_journal:
2665         jbd2_journal_destroy(journal);
2666 out_bdev:
2667         ext4_blkdev_put(bdev);
2668         return NULL;
2669 }
2670
2671 static int ext4_load_journal(struct super_block *sb,
2672                              struct ext4_super_block *es,
2673                              unsigned long journal_devnum)
2674 {
2675         journal_t *journal;
2676         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
2677         dev_t journal_dev;
2678         int err = 0;
2679         int really_read_only;
2680
2681         if (journal_devnum &&
2682             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2683                 printk(KERN_INFO "EXT4-fs: external journal device major/minor "
2684                         "numbers have changed\n");
2685                 journal_dev = new_decode_dev(journal_devnum);
2686         } else
2687                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
2688
2689         really_read_only = bdev_read_only(sb->s_bdev);
2690
2691         /*
2692          * Are we loading a blank journal or performing recovery after a
2693          * crash?  For recovery, we need to check in advance whether we
2694          * can get read-write access to the device.
2695          */
2696
2697         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2698                 if (sb->s_flags & MS_RDONLY) {
2699                         printk(KERN_INFO "EXT4-fs: INFO: recovery "
2700                                         "required on readonly filesystem.\n");
2701                         if (really_read_only) {
2702                                 printk(KERN_ERR "EXT4-fs: write access "
2703                                         "unavailable, cannot proceed.\n");
2704                                 return -EROFS;
2705                         }
2706                         printk(KERN_INFO "EXT4-fs: write access will "
2707                                "be enabled during recovery.\n");
2708                 }
2709         }
2710
2711         if (journal_inum && journal_dev) {
2712                 printk(KERN_ERR "EXT4-fs: filesystem has both journal "
2713                        "and inode journals!\n");
2714                 return -EINVAL;
2715         }
2716
2717         if (journal_inum) {
2718                 if (!(journal = ext4_get_journal(sb, journal_inum)))
2719                         return -EINVAL;
2720         } else {
2721                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
2722                         return -EINVAL;
2723         }
2724
2725         if (journal->j_flags & JBD2_BARRIER)
2726                 printk(KERN_INFO "EXT4-fs: barriers enabled\n");
2727         else
2728                 printk(KERN_INFO "EXT4-fs: barriers disabled\n");
2729
2730         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
2731                 err = jbd2_journal_update_format(journal);
2732                 if (err)  {
2733                         printk(KERN_ERR "EXT4-fs: error updating journal.\n");
2734                         jbd2_journal_destroy(journal);
2735                         return err;
2736                 }
2737         }
2738
2739         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
2740                 err = jbd2_journal_wipe(journal, !really_read_only);
2741         if (!err)
2742                 err = jbd2_journal_load(journal);
2743
2744         if (err) {
2745                 printk(KERN_ERR "EXT4-fs: error loading journal.\n");
2746                 jbd2_journal_destroy(journal);
2747                 return err;
2748         }
2749
2750         EXT4_SB(sb)->s_journal = journal;
2751         ext4_clear_journal_err(sb, es);
2752
2753         if (journal_devnum &&
2754             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2755                 es->s_journal_dev = cpu_to_le32(journal_devnum);
2756                 sb->s_dirt = 1;
2757
2758                 /* Make sure we flush the recovery flag to disk. */
2759                 ext4_commit_super(sb, es, 1);
2760         }
2761
2762         return 0;
2763 }
2764
2765 static int ext4_create_journal(struct super_block *sb,
2766                                struct ext4_super_block *es,
2767                                unsigned int journal_inum)
2768 {
2769         journal_t *journal;
2770         int err;
2771
2772         if (sb->s_flags & MS_RDONLY) {
2773                 printk(KERN_ERR "EXT4-fs: readonly filesystem when trying to "
2774                                 "create journal.\n");
2775                 return -EROFS;
2776         }
2777
2778         journal = ext4_get_journal(sb, journal_inum);
2779         if (!journal)
2780                 return -EINVAL;
2781
2782         printk(KERN_INFO "EXT4-fs: creating new journal on inode %u\n",
2783                journal_inum);
2784
2785         err = jbd2_journal_create(journal);
2786         if (err) {
2787                 printk(KERN_ERR "EXT4-fs: error creating journal.\n");
2788                 jbd2_journal_destroy(journal);
2789                 return -EIO;
2790         }
2791
2792         EXT4_SB(sb)->s_journal = journal;
2793
2794         ext4_update_dynamic_rev(sb);
2795         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2796         EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL);
2797
2798         es->s_journal_inum = cpu_to_le32(journal_inum);
2799         sb->s_dirt = 1;
2800
2801         /* Make sure we flush the recovery flag to disk. */
2802         ext4_commit_super(sb, es, 1);
2803
2804         return 0;
2805 }
2806
2807 static void ext4_commit_super(struct super_block *sb,
2808                               struct ext4_super_block *es, int sync)
2809 {
2810         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
2811
2812         if (!sbh)
2813                 return;
2814         if (buffer_write_io_error(sbh)) {
2815                 /*
2816                  * Oh, dear.  A previous attempt to write the
2817                  * superblock failed.  This could happen because the
2818                  * USB device was yanked out.  Or it could happen to
2819                  * be a transient write error and maybe the block will
2820                  * be remapped.  Nothing we can do but to retry the
2821                  * write and hope for the best.
2822                  */
2823                 printk(KERN_ERR "ext4: previous I/O error to "
2824                        "superblock detected for %s.\n", sb->s_id);
2825                 clear_buffer_write_io_error(sbh);
2826                 set_buffer_uptodate(sbh);
2827         }
2828         es->s_wtime = cpu_to_le32(get_seconds());
2829         ext4_free_blocks_count_set(es, ext4_count_free_blocks(sb));
2830         es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
2831         BUFFER_TRACE(sbh, "marking dirty");
2832         mark_buffer_dirty(sbh);
2833         if (sync) {
2834                 sync_dirty_buffer(sbh);
2835                 if (buffer_write_io_error(sbh)) {
2836                         printk(KERN_ERR "ext4: I/O error while writing "
2837                                "superblock for %s.\n", sb->s_id);
2838                         clear_buffer_write_io_error(sbh);
2839                         set_buffer_uptodate(sbh);
2840                 }
2841         }
2842 }
2843
2844
2845 /*
2846  * Have we just finished recovery?  If so, and if we are mounting (or
2847  * remounting) the filesystem readonly, then we will end up with a
2848  * consistent fs on disk.  Record that fact.
2849  */
2850 static void ext4_mark_recovery_complete(struct super_block *sb,
2851                                         struct ext4_super_block *es)
2852 {
2853         journal_t *journal = EXT4_SB(sb)->s_journal;
2854
2855         jbd2_journal_lock_updates(journal);
2856         jbd2_journal_flush(journal);
2857         lock_super(sb);
2858         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
2859             sb->s_flags & MS_RDONLY) {
2860                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2861                 sb->s_dirt = 0;
2862                 ext4_commit_super(sb, es, 1);
2863         }
2864         unlock_super(sb);
2865         jbd2_journal_unlock_updates(journal);
2866 }
2867
2868 /*
2869  * If we are mounting (or read-write remounting) a filesystem whose journal
2870  * has recorded an error from a previous lifetime, move that error to the
2871  * main filesystem now.
2872  */
2873 static void ext4_clear_journal_err(struct super_block *sb,
2874                                    struct ext4_super_block *es)
2875 {
2876         journal_t *journal;
2877         int j_errno;
2878         const char *errstr;
2879
2880         journal = EXT4_SB(sb)->s_journal;
2881
2882         /*
2883          * Now check for any error status which may have been recorded in the
2884          * journal by a prior ext4_error() or ext4_abort()
2885          */
2886
2887         j_errno = jbd2_journal_errno(journal);
2888         if (j_errno) {
2889                 char nbuf[16];
2890
2891                 errstr = ext4_decode_error(sb, j_errno, nbuf);
2892                 ext4_warning(sb, __func__, "Filesystem error recorded "
2893                              "from previous mount: %s", errstr);
2894                 ext4_warning(sb, __func__, "Marking fs in need of "
2895                              "filesystem check.");
2896
2897                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2898                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2899                 ext4_commit_super(sb, es, 1);
2900
2901                 jbd2_journal_clear_err(journal);
2902         }
2903 }
2904
2905 /*
2906  * Force the running and committing transactions to commit,
2907  * and wait on the commit.
2908  */
2909 int ext4_force_commit(struct super_block *sb)
2910 {
2911         journal_t *journal;
2912         int ret;
2913
2914         if (sb->s_flags & MS_RDONLY)
2915                 return 0;
2916
2917         journal = EXT4_SB(sb)->s_journal;
2918         sb->s_dirt = 0;
2919         ret = ext4_journal_force_commit(journal);
2920         return ret;
2921 }
2922
2923 /*
2924  * Ext4 always journals updates to the superblock itself, so we don't
2925  * have to propagate any other updates to the superblock on disk at this
2926  * point.  Just start an async writeback to get the buffers on their way
2927  * to the disk.
2928  *
2929  * This implicitly triggers the writebehind on sync().
2930  */
2931
2932 static void ext4_write_super(struct super_block *sb)
2933 {
2934         if (mutex_trylock(&sb->s_lock) != 0)
2935                 BUG();
2936         sb->s_dirt = 0;
2937 }
2938
2939 static int ext4_sync_fs(struct super_block *sb, int wait)
2940 {
2941         tid_t target;
2942
2943         trace_mark(ext4_sync_fs, "dev %s wait %d", sb->s_id, wait);
2944         sb->s_dirt = 0;
2945         if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, &target)) {
2946                 if (wait)
2947                         jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, target);
2948         }
2949         return 0;
2950 }
2951
2952 /*
2953  * LVM calls this function before a (read-only) snapshot is created.  This
2954  * gives us a chance to flush the journal completely and mark the fs clean.
2955  */
2956 static void ext4_write_super_lockfs(struct super_block *sb)
2957 {
2958         sb->s_dirt = 0;
2959
2960         if (!(sb->s_flags & MS_RDONLY)) {
2961                 journal_t *journal = EXT4_SB(sb)->s_journal;
2962
2963                 /* Now we set up the journal barrier. */
2964                 jbd2_journal_lock_updates(journal);
2965                 jbd2_journal_flush(journal);
2966
2967                 /* Journal blocked and flushed, clear needs_recovery flag. */
2968                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2969                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2970         }
2971 }
2972
2973 /*
2974  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
2975  * flag here, even though the filesystem is not technically dirty yet.
2976  */
2977 static void ext4_unlockfs(struct super_block *sb)
2978 {
2979         if (!(sb->s_flags & MS_RDONLY)) {
2980                 lock_super(sb);
2981                 /* Reser the needs_recovery flag before the fs is unlocked. */
2982                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2983                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2984                 unlock_super(sb);
2985                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
2986         }
2987 }
2988
2989 static int ext4_remount(struct super_block *sb, int *flags, char *data)
2990 {
2991         struct ext4_super_block *es;
2992         struct ext4_sb_info *sbi = EXT4_SB(sb);
2993         ext4_fsblk_t n_blocks_count = 0;
2994         unsigned long old_sb_flags;
2995         struct ext4_mount_options old_opts;
2996         ext4_group_t g;
2997         int err;
2998 #ifdef CONFIG_QUOTA
2999         int i;
3000 #endif
3001
3002         /* Store the original options */
3003         old_sb_flags = sb->s_flags;
3004         old_opts.s_mount_opt = sbi->s_mount_opt;
3005         old_opts.s_resuid = sbi->s_resuid;
3006         old_opts.s_resgid = sbi->s_resgid;
3007         old_opts.s_commit_interval = sbi->s_commit_interval;
3008 #ifdef CONFIG_QUOTA
3009         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
3010         for (i = 0; i < MAXQUOTAS; i++)
3011                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
3012 #endif
3013
3014         /*
3015          * Allow the "check" option to be passed as a remount option.
3016          */
3017         if (!parse_options(data, sb, NULL, NULL, &n_blocks_count, 1)) {
3018                 err = -EINVAL;
3019                 goto restore_opts;
3020         }
3021
3022         if (sbi->s_mount_opt & EXT4_MOUNT_ABORT)
3023                 ext4_abort(sb, __func__, "Abort forced by user");
3024
3025         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3026                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
3027
3028         es = sbi->s_es;
3029
3030         ext4_init_journal_params(sb, sbi->s_journal);
3031
3032         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3033                 n_blocks_count > ext4_blocks_count(es)) {
3034                 if (sbi->s_mount_opt & EXT4_MOUNT_ABORT) {
3035                         err = -EROFS;
3036                         goto restore_opts;
3037                 }
3038
3039                 if (*flags & MS_RDONLY) {
3040                         /*
3041                          * First of all, the unconditional stuff we have to do
3042                          * to disable replay of the journal when we next remount
3043                          */
3044                         sb->s_flags |= MS_RDONLY;
3045
3046                         /*
3047                          * OK, test if we are remounting a valid rw partition
3048                          * readonly, and if so set the rdonly flag and then
3049                          * mark the partition as valid again.
3050                          */
3051                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3052                             (sbi->s_mount_state & EXT4_VALID_FS))
3053                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3054
3055                         /*
3056                          * We have to unlock super so that we can wait for
3057                          * transactions.
3058                          */
3059                         unlock_super(sb);
3060                         ext4_mark_recovery_complete(sb, es);
3061                         lock_super(sb);
3062                 } else {
3063                         __le32 ret;
3064                         if ((ret = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3065                                         ~EXT4_FEATURE_RO_COMPAT_SUPP))) {
3066                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3067                                        "remount RDWR because of unsupported "
3068                                        "optional features (%x).\n",
3069                                        sb->s_id, le32_to_cpu(ret));
3070                                 err = -EROFS;
3071                                 goto restore_opts;
3072                         }
3073
3074                         /*
3075                          * Make sure the group descriptor checksums
3076                          * are sane.  If they aren't, refuse to
3077                          * remount r/w.
3078                          */
3079                         for (g = 0; g < sbi->s_groups_count; g++) {
3080                                 struct ext4_group_desc *gdp =
3081                                         ext4_get_group_desc(sb, g, NULL);
3082
3083                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3084                                         printk(KERN_ERR
3085                "EXT4-fs: ext4_remount: "
3086                 "Checksum for group %lu failed (%u!=%u)\n",
3087                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3088                                                le16_to_cpu(gdp->bg_checksum));
3089                                         err = -EINVAL;
3090                                         goto restore_opts;
3091                                 }
3092                         }
3093
3094                         /*
3095                          * If we have an unprocessed orphan list hanging
3096                          * around from a previously readonly bdev mount,
3097                          * require a full umount/remount for now.
3098                          */
3099                         if (es->s_last_orphan) {
3100                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3101                                        "remount RDWR because of unprocessed "
3102                                        "orphan inode list.  Please "
3103                                        "umount/remount instead.\n",
3104                                        sb->s_id);
3105                                 err = -EINVAL;
3106                                 goto restore_opts;
3107                         }
3108
3109                         /*
3110                          * Mounting a RDONLY partition read-write, so reread
3111                          * and store the current valid flag.  (It may have
3112                          * been changed by e2fsck since we originally mounted
3113                          * the partition.)
3114                          */
3115                         ext4_clear_journal_err(sb, es);
3116                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3117                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3118                                 goto restore_opts;
3119                         if (!ext4_setup_super(sb, es, 0))
3120                                 sb->s_flags &= ~MS_RDONLY;
3121                 }
3122         }
3123 #ifdef CONFIG_QUOTA
3124         /* Release old quota file names */
3125         for (i = 0; i < MAXQUOTAS; i++)
3126                 if (old_opts.s_qf_names[i] &&
3127                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3128                         kfree(old_opts.s_qf_names[i]);
3129 #endif
3130         return 0;
3131 restore_opts:
3132         sb->s_flags = old_sb_flags;
3133         sbi->s_mount_opt = old_opts.s_mount_opt;
3134         sbi->s_resuid = old_opts.s_resuid;
3135         sbi->s_resgid = old_opts.s_resgid;
3136         sbi->s_commit_interval = old_opts.s_commit_interval;
3137 #ifdef CONFIG_QUOTA
3138         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3139         for (i = 0; i < MAXQUOTAS; i++) {
3140                 if (sbi->s_qf_names[i] &&
3141                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3142                         kfree(sbi->s_qf_names[i]);
3143                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3144         }
3145 #endif
3146         return err;
3147 }
3148
3149 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3150 {
3151         struct super_block *sb = dentry->d_sb;
3152         struct ext4_sb_info *sbi = EXT4_SB(sb);
3153         struct ext4_super_block *es = sbi->s_es;
3154         u64 fsid;
3155
3156         if (test_opt(sb, MINIX_DF)) {
3157                 sbi->s_overhead_last = 0;
3158         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3159                 ext4_group_t ngroups = sbi->s_groups_count, i;
3160                 ext4_fsblk_t overhead = 0;
3161                 smp_rmb();
3162
3163                 /*
3164                  * Compute the overhead (FS structures).  This is constant
3165                  * for a given filesystem unless the number of block groups
3166                  * changes so we cache the previous value until it does.
3167                  */
3168
3169                 /*
3170                  * All of the blocks before first_data_block are
3171                  * overhead
3172                  */
3173                 overhead = le32_to_cpu(es->s_first_data_block);
3174
3175                 /*
3176                  * Add the overhead attributed to the superblock and
3177                  * block group descriptors.  If the sparse superblocks
3178                  * feature is turned on, then not all groups have this.
3179                  */
3180                 for (i = 0; i < ngroups; i++) {
3181                         overhead += ext4_bg_has_super(sb, i) +
3182                                 ext4_bg_num_gdb(sb, i);
3183                         cond_resched();
3184                 }
3185
3186                 /*
3187                  * Every block group has an inode bitmap, a block
3188                  * bitmap, and an inode table.
3189                  */
3190                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3191                 sbi->s_overhead_last = overhead;
3192                 smp_wmb();
3193                 sbi->s_blocks_last = ext4_blocks_count(es);
3194         }
3195
3196         buf->f_type = EXT4_SUPER_MAGIC;
3197         buf->f_bsize = sb->s_blocksize;
3198         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3199         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3200                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3201         ext4_free_blocks_count_set(es, buf->f_bfree);
3202         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3203         if (buf->f_bfree < ext4_r_blocks_count(es))
3204                 buf->f_bavail = 0;
3205         buf->f_files = le32_to_cpu(es->s_inodes_count);
3206         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3207         es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
3208         buf->f_namelen = EXT4_NAME_LEN;
3209         fsid = le64_to_cpup((void *)es->s_uuid) ^
3210                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3211         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3212         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3213         return 0;
3214 }
3215
3216 /* Helper function for writing quotas on sync - we need to start transaction before quota file
3217  * is locked for write. Otherwise the are possible deadlocks:
3218  * Process 1                         Process 2
3219  * ext4_create()                     quota_sync()
3220  *   jbd2_journal_start()                   write_dquot()
3221  *   DQUOT_INIT()                        down(dqio_mutex)
3222  *     down(dqio_mutex)                    jbd2_journal_start()
3223  *
3224  */
3225
3226 #ifdef CONFIG_QUOTA
3227
3228 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3229 {
3230         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3231 }
3232
3233 static int ext4_dquot_initialize(struct inode *inode, int type)
3234 {
3235         handle_t *handle;
3236         int ret, err;
3237
3238         /* We may create quota structure so we need to reserve enough blocks */
3239         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_INIT_BLOCKS(inode->i_sb));
3240         if (IS_ERR(handle))
3241                 return PTR_ERR(handle);
3242         ret = dquot_initialize(inode, type);
3243         err = ext4_journal_stop(handle);
3244         if (!ret)
3245                 ret = err;
3246         return ret;
3247 }
3248
3249 static int ext4_dquot_drop(struct inode *inode)
3250 {
3251         handle_t *handle;
3252         int ret, err;
3253
3254         /* We may delete quota structure so we need to reserve enough blocks */
3255         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_DEL_BLOCKS(inode->i_sb));
3256         if (IS_ERR(handle)) {
3257                 /*
3258                  * We call dquot_drop() anyway to at least release references
3259                  * to quota structures so that umount does not hang.
3260                  */
3261                 dquot_drop(inode);
3262                 return PTR_ERR(handle);
3263         }
3264         ret = dquot_drop(inode);
3265         err = ext4_journal_stop(handle);
3266         if (!ret)
3267                 ret = err;
3268         return ret;
3269 }
3270
3271 static int ext4_write_dquot(struct dquot *dquot)
3272 {
3273         int ret, err;
3274         handle_t *handle;
3275         struct inode *inode;
3276
3277         inode = dquot_to_inode(dquot);
3278         handle = ext4_journal_start(inode,
3279                                         EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3280         if (IS_ERR(handle))
3281                 return PTR_ERR(handle);
3282         ret = dquot_commit(dquot);
3283         err = ext4_journal_stop(handle);
3284         if (!ret)
3285                 ret = err;
3286         return ret;
3287 }
3288
3289 static int ext4_acquire_dquot(struct dquot *dquot)
3290 {
3291         int ret, err;
3292         handle_t *handle;
3293
3294         handle = ext4_journal_start(dquot_to_inode(dquot),
3295                                         EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3296         if (IS_ERR(handle))
3297                 return PTR_ERR(handle);
3298         ret = dquot_acquire(dquot);
3299         err = ext4_journal_stop(handle);
3300         if (!ret)
3301                 ret = err;
3302         return ret;
3303 }
3304
3305 static int ext4_release_dquot(struct dquot *dquot)
3306 {
3307         int ret, err;
3308         handle_t *handle;
3309
3310         handle = ext4_journal_start(dquot_to_inode(dquot),
3311                                         EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3312         if (IS_ERR(handle)) {
3313                 /* Release dquot anyway to avoid endless cycle in dqput() */
3314                 dquot_release(dquot);
3315                 return PTR_ERR(handle);
3316         }
3317         ret = dquot_release(dquot);
3318         err = ext4_journal_stop(handle);
3319         if (!ret)
3320                 ret = err;
3321         return ret;
3322 }
3323
3324 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3325 {
3326         /* Are we journaling quotas? */
3327         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3328             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3329                 dquot_mark_dquot_dirty(dquot);
3330                 return ext4_write_dquot(dquot);
3331         } else {
3332                 return dquot_mark_dquot_dirty(dquot);
3333         }
3334 }
3335
3336 static int ext4_write_info(struct super_block *sb, int type)
3337 {
3338         int ret, err;
3339         handle_t *handle;
3340
3341         /* Data block + inode block */
3342         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3343         if (IS_ERR(handle))
3344                 return PTR_ERR(handle);
3345         ret = dquot_commit_info(sb, type);
3346         err = ext4_journal_stop(handle);
3347         if (!ret)
3348                 ret = err;
3349         return ret;
3350 }
3351
3352 /*
3353  * Turn on quotas during mount time - we need to find
3354  * the quota file and such...
3355  */
3356 static int ext4_quota_on_mount(struct super_block *sb, int type)
3357 {
3358         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3359                         EXT4_SB(sb)->s_jquota_fmt, type);
3360 }
3361
3362 /*
3363  * Standard function to be called on quota_on
3364  */
3365 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3366                          char *path, int remount)
3367 {
3368         int err;
3369         struct nameidata nd;
3370
3371         if (!test_opt(sb, QUOTA))
3372                 return -EINVAL;
3373         /* When remounting, no checks are needed and in fact, path is NULL */
3374         if (remount)
3375                 return vfs_quota_on(sb, type, format_id, path, remount);
3376
3377         err = path_lookup(path, LOOKUP_FOLLOW, &nd);
3378         if (err)
3379                 return err;
3380
3381         /* Quotafile not on the same filesystem? */
3382         if (nd.path.mnt->mnt_sb != sb) {
3383                 path_put(&nd.path);
3384                 return -EXDEV;
3385         }
3386         /* Journaling quota? */
3387         if (EXT4_SB(sb)->s_qf_names[type]) {
3388                 /* Quotafile not in fs root? */
3389                 if (nd.path.dentry->d_parent->d_inode != sb->s_root->d_inode)
3390                         printk(KERN_WARNING
3391                                 "EXT4-fs: Quota file not on filesystem root. "
3392                                 "Journaled quota will not work.\n");
3393         }
3394
3395         /*
3396          * When we journal data on quota file, we have to flush journal to see
3397          * all updates to the file when we bypass pagecache...
3398          */
3399         if (ext4_should_journal_data(nd.path.dentry->d_inode)) {
3400                 /*
3401                  * We don't need to lock updates but journal_flush() could
3402                  * otherwise be livelocked...
3403                  */
3404                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3405                 jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3406                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3407         }
3408
3409         err = vfs_quota_on_path(sb, type, format_id, &nd.path);
3410         path_put(&nd.path);
3411         return err;
3412 }
3413
3414 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3415  * acquiring the locks... As quota files are never truncated and quota code
3416  * itself serializes the operations (and noone else should touch the files)
3417  * we don't have to be afraid of races */
3418 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3419                                size_t len, loff_t off)
3420 {
3421         struct inode *inode = sb_dqopt(sb)->files[type];
3422         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3423         int err = 0;
3424         int offset = off & (sb->s_blocksize - 1);
3425         int tocopy;
3426         size_t toread;
3427         struct buffer_head *bh;
3428         loff_t i_size = i_size_read(inode);
3429
3430         if (off > i_size)
3431                 return 0;
3432         if (off+len > i_size)
3433                 len = i_size-off;
3434         toread = len;
3435         while (toread > 0) {
3436                 tocopy = sb->s_blocksize - offset < toread ?
3437                                 sb->s_blocksize - offset : toread;
3438                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3439                 if (err)
3440                         return err;
3441                 if (!bh)        /* A hole? */
3442                         memset(data, 0, tocopy);
3443                 else
3444                         memcpy(data, bh->b_data+offset, tocopy);
3445                 brelse(bh);
3446                 offset = 0;
3447                 toread -= tocopy;
3448                 data += tocopy;
3449                 blk++;
3450         }
3451         return len;
3452 }
3453
3454 /* Write to quotafile (we know the transaction is already started and has
3455  * enough credits) */
3456 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3457                                 const char *data, size_t len, loff_t off)
3458 {
3459         struct inode *inode = sb_dqopt(sb)->files[type];
3460         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3461         int err = 0;
3462         int offset = off & (sb->s_blocksize - 1);
3463         int tocopy;
3464         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3465         size_t towrite = len;
3466         struct buffer_head *bh;
3467         handle_t *handle = journal_current_handle();
3468
3469         if (!handle) {
3470                 printk(KERN_WARNING "EXT4-fs: Quota write (off=%llu, len=%llu)"
3471                         " cancelled because transaction is not started.\n",
3472                         (unsigned long long)off, (unsigned long long)len);
3473                 return -EIO;
3474         }
3475         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3476         while (towrite > 0) {
3477                 tocopy = sb->s_blocksize - offset < towrite ?
3478                                 sb->s_blocksize - offset : towrite;
3479                 bh = ext4_bread(handle, inode, blk, 1, &err);
3480                 if (!bh)
3481                         goto out;
3482                 if (journal_quota) {
3483                         err = ext4_journal_get_write_access(handle, bh);
3484                         if (err) {
3485                                 brelse(bh);
3486                                 goto out;
3487                         }
3488                 }
3489                 lock_buffer(bh);
3490                 memcpy(bh->b_data+offset, data, tocopy);
3491                 flush_dcache_page(bh->b_page);
3492                 unlock_buffer(bh);
3493                 if (journal_quota)
3494                         err = ext4_journal_dirty_metadata(handle, bh);
3495                 else {
3496                         /* Always do at least ordered writes for quotas */
3497                         err = ext4_jbd2_file_inode(handle, inode);
3498                         mark_buffer_dirty(bh);
3499                 }
3500                 brelse(bh);
3501                 if (err)
3502                         goto out;
3503                 offset = 0;
3504                 towrite -= tocopy;
3505                 data += tocopy;
3506                 blk++;
3507         }
3508 out:
3509         if (len == towrite) {
3510                 mutex_unlock(&inode->i_mutex);
3511                 return err;
3512         }
3513         if (inode->i_size < off+len-towrite) {
3514                 i_size_write(inode, off+len-towrite);
3515                 EXT4_I(inode)->i_disksize = inode->i_size;
3516         }
3517         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3518         ext4_mark_inode_dirty(handle, inode);
3519         mutex_unlock(&inode->i_mutex);
3520         return len - towrite;
3521 }
3522
3523 #endif
3524
3525 static int ext4_get_sb(struct file_system_type *fs_type,
3526         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
3527 {
3528         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
3529 }
3530
3531 #ifdef CONFIG_PROC_FS
3532 static int ext4_ui_proc_show(struct seq_file *m, void *v)
3533 {
3534         unsigned int *p = m->private;
3535
3536         seq_printf(m, "%u\n", *p);
3537         return 0;
3538 }
3539
3540 static int ext4_ui_proc_open(struct inode *inode, struct file *file)
3541 {
3542         return single_open(file, ext4_ui_proc_show, PDE(inode)->data);
3543 }
3544
3545 static ssize_t ext4_ui_proc_write(struct file *file, const char __user *buf,
3546                                size_t cnt, loff_t *ppos)
3547 {
3548         unsigned int *p = PDE(file->f_path.dentry->d_inode)->data;
3549         char str[32];
3550         unsigned long value;
3551
3552         if (cnt >= sizeof(str))
3553                 return -EINVAL;
3554         if (copy_from_user(str, buf, cnt))
3555                 return -EFAULT;
3556         value = simple_strtol(str, NULL, 0);
3557         if (value < 0)
3558                 return -ERANGE;
3559         *p = value;
3560         return cnt;
3561 }
3562
3563 const struct file_operations ext4_ui_proc_fops = {
3564         .owner          = THIS_MODULE,
3565         .open           = ext4_ui_proc_open,
3566         .read           = seq_read,
3567         .llseek         = seq_lseek,
3568         .release        = single_release,
3569         .write          = ext4_ui_proc_write,
3570 };
3571 #endif
3572
3573 static struct file_system_type ext4_fs_type = {
3574         .owner          = THIS_MODULE,
3575         .name           = "ext4",
3576         .get_sb         = ext4_get_sb,
3577         .kill_sb        = kill_block_super,
3578         .fs_flags       = FS_REQUIRES_DEV,
3579 };
3580
3581 #ifdef CONFIG_EXT4DEV_COMPAT
3582 static int ext4dev_get_sb(struct file_system_type *fs_type,
3583         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
3584 {
3585         printk(KERN_WARNING "EXT4-fs: Update your userspace programs "
3586                "to mount using ext4\n");
3587         printk(KERN_WARNING "EXT4-fs: ext4dev backwards compatibility "
3588                "will go away by 2.6.31\n");
3589         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
3590 }
3591
3592 static struct file_system_type ext4dev_fs_type = {
3593         .owner          = THIS_MODULE,
3594         .name           = "ext4dev",
3595         .get_sb         = ext4dev_get_sb,
3596         .kill_sb        = kill_block_super,
3597         .fs_flags       = FS_REQUIRES_DEV,
3598 };
3599 MODULE_ALIAS("ext4dev");
3600 #endif
3601
3602 static int __init init_ext4_fs(void)
3603 {
3604         int err;
3605
3606         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
3607         err = init_ext4_mballoc();
3608         if (err)
3609                 return err;
3610
3611         err = init_ext4_xattr();
3612         if (err)
3613                 goto out2;
3614         err = init_inodecache();
3615         if (err)
3616                 goto out1;
3617         err = register_filesystem(&ext4_fs_type);
3618         if (err)
3619                 goto out;
3620 #ifdef CONFIG_EXT4DEV_COMPAT
3621         err = register_filesystem(&ext4dev_fs_type);
3622         if (err) {
3623                 unregister_filesystem(&ext4_fs_type);
3624                 goto out;
3625         }
3626 #endif
3627         return 0;
3628 out:
3629         destroy_inodecache();
3630 out1:
3631         exit_ext4_xattr();
3632 out2:
3633         exit_ext4_mballoc();
3634         return err;
3635 }
3636
3637 static void __exit exit_ext4_fs(void)
3638 {
3639         unregister_filesystem(&ext4_fs_type);
3640 #ifdef CONFIG_EXT4DEV_COMPAT
3641         unregister_filesystem(&ext4dev_fs_type);
3642 #endif
3643         destroy_inodecache();
3644         exit_ext4_xattr();
3645         exit_ext4_mballoc();
3646         remove_proc_entry("fs/ext4", NULL);
3647 }
3648
3649 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
3650 MODULE_DESCRIPTION("Fourth Extended Filesystem with extents");
3651 MODULE_LICENSE("GPL");
3652 module_init(init_ext4_fs)
3653 module_exit(exit_ext4_fs)