err.no Git - linux-2.6/blob - 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/ext4_fs.h>
  25 #include <linux/ext4_jbd2.h>
  26 #include <linux/slab.h>
  27 #include <linux/init.h>
  28 #include <linux/blkdev.h>
  29 #include <linux/parser.h>
  30 #include <linux/smp_lock.h>
  31 #include <linux/buffer_head.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38
  39 #include <asm/uaccess.h>
  40
  41 #include "xattr.h"
  42 #include "acl.h"
  43 #include "namei.h"
  44
  45 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  46                              unsigned long journal_devnum);
  47 static int ext4_create_journal(struct super_block *, struct ext4_super_block *,
  48                                unsigned int);
  49 static void ext4_commit_super (struct super_block * sb,
  50                                struct ext4_super_block * es,
  51                                int sync);
  52 static void ext4_mark_recovery_complete(struct super_block * sb,
  53                                         struct ext4_super_block * es);
  54 static void ext4_clear_journal_err(struct super_block * sb,
  55                                    struct ext4_super_block * es);
  56 static int ext4_sync_fs(struct super_block *sb, int wait);
  57 static const char *ext4_decode_error(struct super_block * sb, int errno,
  58                                      char nbuf[16]);
  59 static int ext4_remount (struct super_block * sb, int * flags, char * data);
  60 static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf);
  61 static void ext4_unlockfs(struct super_block *sb);
  62 static void ext4_write_super (struct super_block * sb);
  63 static void ext4_write_super_lockfs(struct super_block *sb);
  64
  65 /*
  66  * Wrappers for jbd2_journal_start/end.
  67  *
  68  * The only special thing we need to do here is to make sure that all
  69  * journal_end calls result in the superblock being marked dirty, so
  70  * that sync() will call the filesystem's write_super callback if
  71  * appropriate.
  72  */
  73 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
  74 {
  75         journal_t *journal;
  76
  77         if (sb->s_flags & MS_RDONLY)
  78                 return ERR_PTR(-EROFS);
  79
  80         /* Special case here: if the journal has aborted behind our
  81          * backs (eg. EIO in the commit thread), then we still need to
  82          * take the FS itself readonly cleanly. */
  83         journal = EXT4_SB(sb)->s_journal;
  84         if (is_journal_aborted(journal)) {
  85                 ext4_abort(sb, __FUNCTION__,
  86                            "Detected aborted journal");
  87                 return ERR_PTR(-EROFS);
  88         }
  89
  90         return jbd2_journal_start(journal, nblocks);
  91 }
  92
  93 /*
  94  * The only special thing we need to do here is to make sure that all
  95  * jbd2_journal_stop calls result in the superblock being marked dirty, so
  96  * that sync() will call the filesystem's write_super callback if
  97  * appropriate.
  98  */
  99 int __ext4_journal_stop(const char *where, handle_t *handle)
 100 {
 101         struct super_block *sb;
 102         int err;
 103         int rc;
 104
 105         sb = handle->h_transaction->t_journal->j_private;
 106         err = handle->h_err;
 107         rc = jbd2_journal_stop(handle);
 108
 109         if (!err)
 110                 err = rc;
 111         if (err)
 112                 __ext4_std_error(sb, where, err);
 113         return err;
 114 }
 115
 116 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 117                 struct buffer_head *bh, handle_t *handle, int err)
 118 {
 119         char nbuf[16];
 120         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 121
 122         if (bh)
 123                 BUFFER_TRACE(bh, "abort");
 124
 125         if (!handle->h_err)
 126                 handle->h_err = err;
 127
 128         if (is_handle_aborted(handle))
 129                 return;
 130
 131         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
 132                caller, errstr, err_fn);
 133
 134         jbd2_journal_abort_handle(handle);
 135 }
 136
 137 /* Deal with the reporting of failure conditions on a filesystem such as
 138  * inconsistencies detected or read IO failures.
 139  *
 140  * On ext2, we can store the error state of the filesystem in the
 141  * superblock.  That is not possible on ext4, because we may have other
 142  * write ordering constraints on the superblock which prevent us from
 143  * writing it out straight away; and given that the journal is about to
 144  * be aborted, we can't rely on the current, or future, transactions to
 145  * write out the superblock safely.
 146  *
 147  * We'll just use the jbd2_journal_abort() error code to record an error in
 148  * the journal instead.  On recovery, the journal will compain about
 149  * that error until we've noted it down and cleared it.
 150  */
 151
 152 static void ext4_handle_error(struct super_block *sb)
 153 {
 154         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 155
 156         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 157         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 158
 159         if (sb->s_flags & MS_RDONLY)
 160                 return;
 161
 162         if (!test_opt (sb, ERRORS_CONT)) {
 163                 journal_t *journal = EXT4_SB(sb)->s_journal;
 164
 165                 EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 166                 if (journal)
 167                         jbd2_journal_abort(journal, -EIO);
 168         }
 169         if (test_opt (sb, ERRORS_RO)) {
 170                 printk (KERN_CRIT "Remounting filesystem read-only\n");
 171                 sb->s_flags |= MS_RDONLY;
 172         }
 173         ext4_commit_super(sb, es, 1);
 174         if (test_opt(sb, ERRORS_PANIC))
 175                 panic("EXT4-fs (device %s): panic forced after error\n",
 176                         sb->s_id);
 177 }
 178
 179 void ext4_error (struct super_block * sb, const char * function,
 180                  const char * fmt, ...)
 181 {
 182         va_list args;
 183
 184         va_start(args, fmt);
 185         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ",sb->s_id, function);
 186         vprintk(fmt, args);
 187         printk("\n");
 188         va_end(args);
 189
 190         ext4_handle_error(sb);
 191 }
 192
 193 static const char *ext4_decode_error(struct super_block * sb, int errno,
 194                                      char nbuf[16])
 195 {
 196         char *errstr = NULL;
 197
 198         switch (errno) {
 199         case -EIO:
 200                 errstr = "IO failure";
 201                 break;
 202         case -ENOMEM:
 203                 errstr = "Out of memory";
 204                 break;
 205         case -EROFS:
 206                 if (!sb || EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT)
 207                         errstr = "Journal has aborted";
 208                 else
 209                         errstr = "Readonly filesystem";
 210                 break;
 211         default:
 212                 /* If the caller passed in an extra buffer for unknown
 213                  * errors, textualise them now.  Else we just return
 214                  * NULL. */
 215                 if (nbuf) {
 216                         /* Check for truncated error codes... */
 217                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 218                                 errstr = nbuf;
 219                 }
 220                 break;
 221         }
 222
 223         return errstr;
 224 }
 225
 226 /* __ext4_std_error decodes expected errors from journaling functions
 227  * automatically and invokes the appropriate error response.  */
 228
 229 void __ext4_std_error (struct super_block * sb, const char * function,
 230                        int errno)
 231 {
 232         char nbuf[16];
 233         const char *errstr;
 234
 235         /* Special case: if the error is EROFS, and we're not already
 236          * inside a transaction, then there's really no point in logging
 237          * an error. */
 238         if (errno == -EROFS && journal_current_handle() == NULL &&
 239             (sb->s_flags & MS_RDONLY))
 240                 return;
 241
 242         errstr = ext4_decode_error(sb, errno, nbuf);
 243         printk (KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
 244                 sb->s_id, function, errstr);
 245
 246         ext4_handle_error(sb);
 247 }
 248
 249 /*
 250  * ext4_abort is a much stronger failure handler than ext4_error.  The
 251  * abort function may be used to deal with unrecoverable failures such
 252  * as journal IO errors or ENOMEM at a critical moment in log management.
 253  *
 254  * We unconditionally force the filesystem into an ABORT|READONLY state,
 255  * unless the error response on the fs has been set to panic in which
 256  * case we take the easy way out and panic immediately.
 257  */
 258
 259 void ext4_abort (struct super_block * sb, const char * function,
 260                  const char * fmt, ...)
 261 {
 262         va_list args;
 263
 264         printk (KERN_CRIT "ext4_abort called.\n");
 265
 266         va_start(args, fmt);
 267         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ",sb->s_id, function);
 268         vprintk(fmt, args);
 269         printk("\n");
 270         va_end(args);
 271
 272         if (test_opt(sb, ERRORS_PANIC))
 273                 panic("EXT4-fs panic from previous error\n");
 274
 275         if (sb->s_flags & MS_RDONLY)
 276                 return;
 277
 278         printk(KERN_CRIT "Remounting filesystem read-only\n");
 279         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 280         sb->s_flags |= MS_RDONLY;
 281         EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 282         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 283 }
 284
 285 void ext4_warning (struct super_block * sb, const char * function,
 286                    const char * fmt, ...)
 287 {
 288         va_list args;
 289
 290         va_start(args, fmt);
 291         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
 292                sb->s_id, function);
 293         vprintk(fmt, args);
 294         printk("\n");
 295         va_end(args);
 296 }
 297
 298 void ext4_update_dynamic_rev(struct super_block *sb)
 299 {
 300         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 301
 302         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 303                 return;
 304
 305         ext4_warning(sb, __FUNCTION__,
 306                      "updating to rev %d because of new feature flag, "
 307                      "running e2fsck is recommended",
 308                      EXT4_DYNAMIC_REV);
 309
 310         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 311         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 312         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 313         /* leave es->s_feature_*compat flags alone */
 314         /* es->s_uuid will be set by e2fsck if empty */
 315
 316         /*
 317          * The rest of the superblock fields should be zero, and if not it
 318          * means they are likely already in use, so leave them alone.  We
 319          * can leave it up to e2fsck to clean up any inconsistencies there.
 320          */
 321 }
 322
 323 /*
 324  * Open the external journal device
 325  */
 326 static struct block_device *ext4_blkdev_get(dev_t dev)
 327 {
 328         struct block_device *bdev;
 329         char b[BDEVNAME_SIZE];
 330
 331         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 332         if (IS_ERR(bdev))
 333                 goto fail;
 334         return bdev;
 335
 336 fail:
 337         printk(KERN_ERR "EXT4: failed to open journal device %s: %ld\n",
 338                         __bdevname(dev, b), PTR_ERR(bdev));
 339         return NULL;
 340 }
 341
 342 /*
 343  * Release the journal device
 344  */
 345 static int ext4_blkdev_put(struct block_device *bdev)
 346 {
 347         bd_release(bdev);
 348         return blkdev_put(bdev);
 349 }
 350
 351 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 352 {
 353         struct block_device *bdev;
 354         int ret = -ENODEV;
 355
 356         bdev = sbi->journal_bdev;
 357         if (bdev) {
 358                 ret = ext4_blkdev_put(bdev);
 359                 sbi->journal_bdev = NULL;
 360         }
 361         return ret;
 362 }
 363
 364 static inline struct inode *orphan_list_entry(struct list_head *l)
 365 {
 366         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 367 }
 368
 369 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 370 {
 371         struct list_head *l;
 372
 373         printk(KERN_ERR "sb orphan head is %d\n",
 374                le32_to_cpu(sbi->s_es->s_last_orphan));
 375
 376         printk(KERN_ERR "sb_info orphan list:\n");
 377         list_for_each(l, &sbi->s_orphan) {
 378                 struct inode *inode = orphan_list_entry(l);
 379                 printk(KERN_ERR "  "
 380                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 381                        inode->i_sb->s_id, inode->i_ino, inode,
 382                        inode->i_mode, inode->i_nlink,
 383                        NEXT_ORPHAN(inode));
 384         }
 385 }
 386
 387 static void ext4_put_super (struct super_block * sb)
 388 {
 389         struct ext4_sb_info *sbi = EXT4_SB(sb);
 390         struct ext4_super_block *es = sbi->s_es;
 391         int i;
 392
 393         ext4_ext_release(sb);
 394         ext4_xattr_put_super(sb);
 395         jbd2_journal_destroy(sbi->s_journal);
 396         if (!(sb->s_flags & MS_RDONLY)) {
 397                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 398                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 399                 BUFFER_TRACE(sbi->s_sbh, "marking dirty");
 400                 mark_buffer_dirty(sbi->s_sbh);
 401                 ext4_commit_super(sb, es, 1);
 402         }
 403
 404         for (i = 0; i < sbi->s_gdb_count; i++)
 405                 brelse(sbi->s_group_desc[i]);
 406         kfree(sbi->s_group_desc);
 407         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 408         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 409         percpu_counter_destroy(&sbi->s_dirs_counter);
 410         brelse(sbi->s_sbh);
 411 #ifdef CONFIG_QUOTA
 412         for (i = 0; i < MAXQUOTAS; i++)
 413                 kfree(sbi->s_qf_names[i]);
 414 #endif
 415
 416         /* Debugging code just in case the in-memory inode orphan list
 417          * isn't empty.  The on-disk one can be non-empty if we've
 418          * detected an error and taken the fs readonly, but the
 419          * in-memory list had better be clean by this point. */
 420         if (!list_empty(&sbi->s_orphan))
 421                 dump_orphan_list(sb, sbi);
 422         J_ASSERT(list_empty(&sbi->s_orphan));
 423
 424         invalidate_bdev(sb->s_bdev, 0);
 425         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 426                 /*
 427                  * Invalidate the journal device's buffers.  We don't want them
 428                  * floating about in memory - the physical journal device may
 429                  * hotswapped, and it breaks the `ro-after' testing code.
 430                  */
 431                 sync_blockdev(sbi->journal_bdev);
 432                 invalidate_bdev(sbi->journal_bdev, 0);
 433                 ext4_blkdev_remove(sbi);
 434         }
 435         sb->s_fs_info = NULL;
 436         kfree(sbi);
 437         return;
 438 }
 439
 440 static kmem_cache_t *ext4_inode_cachep;
 441
 442 /*
 443  * Called inside transaction, so use GFP_NOFS
 444  */
 445 static struct inode *ext4_alloc_inode(struct super_block *sb)
 446 {
 447         struct ext4_inode_info *ei;
 448
 449         ei = kmem_cache_alloc(ext4_inode_cachep, SLAB_NOFS);
 450         if (!ei)
 451                 return NULL;
 452 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 453         ei->i_acl = EXT4_ACL_NOT_CACHED;
 454         ei->i_default_acl = EXT4_ACL_NOT_CACHED;
 455 #endif
 456         ei->i_block_alloc_info = NULL;
 457         ei->vfs_inode.i_version = 1;
 458         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 459         return &ei->vfs_inode;
 460 }
 461
 462 static void ext4_destroy_inode(struct inode *inode)
 463 {
 464         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 465 }
 466
 467 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
 468 {
 469         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 470
 471         if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
 472             SLAB_CTOR_CONSTRUCTOR) {
 473                 INIT_LIST_HEAD(&ei->i_orphan);
 474 #ifdef CONFIG_EXT4DEV_FS_XATTR
 475                 init_rwsem(&ei->xattr_sem);
 476 #endif
 477                 mutex_init(&ei->truncate_mutex);
 478                 inode_init_once(&ei->vfs_inode);
 479         }
 480 }
 481
 482 static int init_inodecache(void)
 483 {
 484         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 485                                              sizeof(struct ext4_inode_info),
 486                                              0, (SLAB_RECLAIM_ACCOUNT|
 487                                                 SLAB_MEM_SPREAD),
 488                                              init_once, NULL);
 489         if (ext4_inode_cachep == NULL)
 490                 return -ENOMEM;
 491         return 0;
 492 }
 493
 494 static void destroy_inodecache(void)
 495 {
 496         kmem_cache_destroy(ext4_inode_cachep);
 497 }
 498
 499 static void ext4_clear_inode(struct inode *inode)
 500 {
 501         struct ext4_block_alloc_info *rsv = EXT4_I(inode)->i_block_alloc_info;
 502 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 503         if (EXT4_I(inode)->i_acl &&
 504                         EXT4_I(inode)->i_acl != EXT4_ACL_NOT_CACHED) {
 505                 posix_acl_release(EXT4_I(inode)->i_acl);
 506                 EXT4_I(inode)->i_acl = EXT4_ACL_NOT_CACHED;
 507         }
 508         if (EXT4_I(inode)->i_default_acl &&
 509                         EXT4_I(inode)->i_default_acl != EXT4_ACL_NOT_CACHED) {
 510                 posix_acl_release(EXT4_I(inode)->i_default_acl);
 511                 EXT4_I(inode)->i_default_acl = EXT4_ACL_NOT_CACHED;
 512         }
 513 #endif
 514         ext4_discard_reservation(inode);
 515         EXT4_I(inode)->i_block_alloc_info = NULL;
 516         if (unlikely(rsv))
 517                 kfree(rsv);
 518 }
 519
 520 static inline void ext4_show_quota_options(struct seq_file *seq, struct super_block *sb)
 521 {
 522 #if defined(CONFIG_QUOTA)
 523         struct ext4_sb_info *sbi = EXT4_SB(sb);
 524
 525         if (sbi->s_jquota_fmt)
 526                 seq_printf(seq, ",jqfmt=%s",
 527                 (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold": "vfsv0");
 528
 529         if (sbi->s_qf_names[USRQUOTA])
 530                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 531
 532         if (sbi->s_qf_names[GRPQUOTA])
 533                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 534
 535         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
 536                 seq_puts(seq, ",usrquota");
 537
 538         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
 539                 seq_puts(seq, ",grpquota");
 540 #endif
 541 }
 542
 543 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 544 {
 545         struct super_block *sb = vfs->mnt_sb;
 546
 547         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 548                 seq_puts(seq, ",data=journal");
 549         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 550                 seq_puts(seq, ",data=ordered");
 551         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 552                 seq_puts(seq, ",data=writeback");
 553
 554         ext4_show_quota_options(seq, sb);
 555
 556         return 0;
 557 }
 558
 559
 560 static struct dentry *ext4_get_dentry(struct super_block *sb, void *vobjp)
 561 {
 562         __u32 *objp = vobjp;
 563         unsigned long ino = objp[0];
 564         __u32 generation = objp[1];
 565         struct inode *inode;
 566         struct dentry *result;
 567
 568         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 569                 return ERR_PTR(-ESTALE);
 570         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 571                 return ERR_PTR(-ESTALE);
 572
 573         /* iget isn't really right if the inode is currently unallocated!!
 574          *
 575          * ext4_read_inode will return a bad_inode if the inode had been
 576          * deleted, so we should be safe.
 577          *
 578          * Currently we don't know the generation for parent directory, so
 579          * a generation of 0 means "accept any"
 580          */
 581         inode = iget(sb, ino);
 582         if (inode == NULL)
 583                 return ERR_PTR(-ENOMEM);
 584         if (is_bad_inode(inode) ||
 585             (generation && inode->i_generation != generation)) {
 586                 iput(inode);
 587                 return ERR_PTR(-ESTALE);
 588         }
 589         /* now to find a dentry.
 590          * If possible, get a well-connected one
 591          */
 592         result = d_alloc_anon(inode);
 593         if (!result) {
 594                 iput(inode);
 595                 return ERR_PTR(-ENOMEM);
 596         }
 597         return result;
 598 }
 599
 600 #ifdef CONFIG_QUOTA
 601 #define QTYPE2NAME(t) ((t)==USRQUOTA?"user":"group")
 602 #define QTYPE2MOPT(on, t) ((t)==USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
 603
 604 static int ext4_dquot_initialize(struct inode *inode, int type);
 605 static int ext4_dquot_drop(struct inode *inode);
 606 static int ext4_write_dquot(struct dquot *dquot);
 607 static int ext4_acquire_dquot(struct dquot *dquot);
 608 static int ext4_release_dquot(struct dquot *dquot);
 609 static int ext4_mark_dquot_dirty(struct dquot *dquot);
 610 static int ext4_write_info(struct super_block *sb, int type);
 611 static int ext4_quota_on(struct super_block *sb, int type, int format_id, char *path);
 612 static int ext4_quota_on_mount(struct super_block *sb, int type);
 613 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
 614                                size_t len, loff_t off);
 615 static ssize_t ext4_quota_write(struct super_block *sb, int type,
 616                                 const char *data, size_t len, loff_t off);
 617
 618 static struct dquot_operations ext4_quota_operations = {
 619         .initialize     = ext4_dquot_initialize,
 620         .drop           = ext4_dquot_drop,
 621         .alloc_space    = dquot_alloc_space,
 622         .alloc_inode    = dquot_alloc_inode,
 623         .free_space     = dquot_free_space,
 624         .free_inode     = dquot_free_inode,
 625         .transfer       = dquot_transfer,
 626         .write_dquot    = ext4_write_dquot,
 627         .acquire_dquot  = ext4_acquire_dquot,
 628         .release_dquot  = ext4_release_dquot,
 629         .mark_dirty     = ext4_mark_dquot_dirty,
 630         .write_info     = ext4_write_info
 631 };
 632
 633 static struct quotactl_ops ext4_qctl_operations = {
 634         .quota_on       = ext4_quota_on,
 635         .quota_off      = vfs_quota_off,
 636         .quota_sync     = vfs_quota_sync,
 637         .get_info       = vfs_get_dqinfo,
 638         .set_info       = vfs_set_dqinfo,
 639         .get_dqblk      = vfs_get_dqblk,
 640         .set_dqblk      = vfs_set_dqblk
 641 };
 642 #endif
 643
 644 static struct super_operations ext4_sops = {
 645         .alloc_inode    = ext4_alloc_inode,
 646         .destroy_inode  = ext4_destroy_inode,
 647         .read_inode     = ext4_read_inode,
 648         .write_inode    = ext4_write_inode,
 649         .dirty_inode    = ext4_dirty_inode,
 650         .delete_inode   = ext4_delete_inode,
 651         .put_super      = ext4_put_super,
 652         .write_super    = ext4_write_super,
 653         .sync_fs        = ext4_sync_fs,
 654         .write_super_lockfs = ext4_write_super_lockfs,
 655         .unlockfs       = ext4_unlockfs,
 656         .statfs         = ext4_statfs,
 657         .remount_fs     = ext4_remount,
 658         .clear_inode    = ext4_clear_inode,
 659         .show_options   = ext4_show_options,
 660 #ifdef CONFIG_QUOTA
 661         .quota_read     = ext4_quota_read,
 662         .quota_write    = ext4_quota_write,
 663 #endif
 664 };
 665
 666 static struct export_operations ext4_export_ops = {
 667         .get_parent = ext4_get_parent,
 668         .get_dentry = ext4_get_dentry,
 669 };
 670
 671 enum {
 672         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
 673         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
 674         Opt_nouid32, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov,
 675         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
 676         Opt_reservation, Opt_noreservation, Opt_noload, Opt_nobh, Opt_bh,
 677         Opt_commit, Opt_journal_update, Opt_journal_inum, Opt_journal_dev,
 678         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
 679         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
 680         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
 681         Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
 682         Opt_grpquota, Opt_extents,
 683 };
 684
 685 static match_table_t tokens = {
 686         {Opt_bsd_df, "bsddf"},
 687         {Opt_minix_df, "minixdf"},
 688         {Opt_grpid, "grpid"},
 689         {Opt_grpid, "bsdgroups"},
 690         {Opt_nogrpid, "nogrpid"},
 691         {Opt_nogrpid, "sysvgroups"},
 692         {Opt_resgid, "resgid=%u"},
 693         {Opt_resuid, "resuid=%u"},
 694         {Opt_sb, "sb=%u"},
 695         {Opt_err_cont, "errors=continue"},
 696         {Opt_err_panic, "errors=panic"},
 697         {Opt_err_ro, "errors=remount-ro"},
 698         {Opt_nouid32, "nouid32"},
 699         {Opt_nocheck, "nocheck"},
 700         {Opt_nocheck, "check=none"},
 701         {Opt_debug, "debug"},
 702         {Opt_oldalloc, "oldalloc"},
 703         {Opt_orlov, "orlov"},
 704         {Opt_user_xattr, "user_xattr"},
 705         {Opt_nouser_xattr, "nouser_xattr"},
 706         {Opt_acl, "acl"},
 707         {Opt_noacl, "noacl"},
 708         {Opt_reservation, "reservation"},
 709         {Opt_noreservation, "noreservation"},
 710         {Opt_noload, "noload"},
 711         {Opt_nobh, "nobh"},
 712         {Opt_bh, "bh"},
 713         {Opt_commit, "commit=%u"},
 714         {Opt_journal_update, "journal=update"},
 715         {Opt_journal_inum, "journal=%u"},
 716         {Opt_journal_dev, "journal_dev=%u"},
 717         {Opt_abort, "abort"},
 718         {Opt_data_journal, "data=journal"},
 719         {Opt_data_ordered, "data=ordered"},
 720         {Opt_data_writeback, "data=writeback"},
 721         {Opt_offusrjquota, "usrjquota="},
 722         {Opt_usrjquota, "usrjquota=%s"},
 723         {Opt_offgrpjquota, "grpjquota="},
 724         {Opt_grpjquota, "grpjquota=%s"},
 725         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
 726         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
 727         {Opt_grpquota, "grpquota"},
 728         {Opt_noquota, "noquota"},
 729         {Opt_quota, "quota"},
 730         {Opt_usrquota, "usrquota"},
 731         {Opt_barrier, "barrier=%u"},
 732         {Opt_extents, "extents"},
 733         {Opt_err, NULL},
 734         {Opt_resize, "resize"},
 735 };
 736
 737 static ext4_fsblk_t get_sb_block(void **data)
 738 {
 739         ext4_fsblk_t    sb_block;
 740         char            *options = (char *) *data;
 741
 742         if (!options || strncmp(options, "sb=", 3) != 0)
 743                 return 1;       /* Default location */
 744         options += 3;
 745         /*todo: use simple_strtoll with >32bit ext4 */
 746         sb_block = simple_strtoul(options, &options, 0);
 747         if (*options && *options != ',') {
 748                 printk("EXT4-fs: Invalid sb specification: %s\n",
 749                        (char *) *data);
 750                 return 1;
 751         }
 752         if (*options == ',')
 753                 options++;
 754         *data = (void *) options;
 755         return sb_block;
 756 }
 757
 758 static int parse_options (char *options, struct super_block *sb,
 759                           unsigned int *inum, unsigned long *journal_devnum,
 760                           ext4_fsblk_t *n_blocks_count, int is_remount)
 761 {
 762         struct ext4_sb_info *sbi = EXT4_SB(sb);
 763         char * p;
 764         substring_t args[MAX_OPT_ARGS];
 765         int data_opt = 0;
 766         int option;
 767 #ifdef CONFIG_QUOTA
 768         int qtype;
 769         char *qname;
 770 #endif
 771
 772         if (!options)
 773                 return 1;
 774
 775         while ((p = strsep (&options, ",")) != NULL) {
 776                 int token;
 777                 if (!*p)
 778                         continue;
 779
 780                 token = match_token(p, tokens, args);
 781                 switch (token) {
 782                 case Opt_bsd_df:
 783                         clear_opt (sbi->s_mount_opt, MINIX_DF);
 784                         break;
 785                 case Opt_minix_df:
 786                         set_opt (sbi->s_mount_opt, MINIX_DF);
 787                         break;
 788                 case Opt_grpid:
 789                         set_opt (sbi->s_mount_opt, GRPID);
 790                         break;
 791                 case Opt_nogrpid:
 792                         clear_opt (sbi->s_mount_opt, GRPID);
 793                         break;
 794                 case Opt_resuid:
 795                         if (match_int(&args[0], &option))
 796                                 return 0;
 797                         sbi->s_resuid = option;
 798                         break;
 799                 case Opt_resgid:
 800                         if (match_int(&args[0], &option))
 801                                 return 0;
 802                         sbi->s_resgid = option;
 803                         break;
 804                 case Opt_sb:
 805                         /* handled by get_sb_block() instead of here */
 806                         /* *sb_block = match_int(&args[0]); */
 807                         break;
 808                 case Opt_err_panic:
 809                         clear_opt (sbi->s_mount_opt, ERRORS_CONT);
 810                         clear_opt (sbi->s_mount_opt, ERRORS_RO);
 811                         set_opt (sbi->s_mount_opt, ERRORS_PANIC);
 812                         break;
 813                 case Opt_err_ro:
 814                         clear_opt (sbi->s_mount_opt, ERRORS_CONT);
 815                         clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
 816                         set_opt (sbi->s_mount_opt, ERRORS_RO);
 817                         break;
 818                 case Opt_err_cont:
 819                         clear_opt (sbi->s_mount_opt, ERRORS_RO);
 820                         clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
 821                         set_opt (sbi->s_mount_opt, ERRORS_CONT);
 822                         break;
 823                 case Opt_nouid32:
 824                         set_opt (sbi->s_mount_opt, NO_UID32);
 825                         break;
 826                 case Opt_nocheck:
 827                         clear_opt (sbi->s_mount_opt, CHECK);
 828                         break;
 829                 case Opt_debug:
 830                         set_opt (sbi->s_mount_opt, DEBUG);
 831                         break;
 832                 case Opt_oldalloc:
 833                         set_opt (sbi->s_mount_opt, OLDALLOC);
 834                         break;
 835                 case Opt_orlov:
 836                         clear_opt (sbi->s_mount_opt, OLDALLOC);
 837                         break;
 838 #ifdef CONFIG_EXT4DEV_FS_XATTR
 839                 case Opt_user_xattr:
 840                         set_opt (sbi->s_mount_opt, XATTR_USER);
 841                         break;
 842                 case Opt_nouser_xattr:
 843                         clear_opt (sbi->s_mount_opt, XATTR_USER);
 844                         break;
 845 #else
 846                 case Opt_user_xattr:
 847                 case Opt_nouser_xattr:
 848                         printk("EXT4 (no)user_xattr options not supported\n");
 849                         break;
 850 #endif
 851 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 852                 case Opt_acl:
 853                         set_opt(sbi->s_mount_opt, POSIX_ACL);
 854                         break;
 855                 case Opt_noacl:
 856                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
 857                         break;
 858 #else
 859                 case Opt_acl:
 860                 case Opt_noacl:
 861                         printk("EXT4 (no)acl options not supported\n");
 862                         break;
 863 #endif
 864                 case Opt_reservation:
 865                         set_opt(sbi->s_mount_opt, RESERVATION);
 866                         break;
 867                 case Opt_noreservation:
 868                         clear_opt(sbi->s_mount_opt, RESERVATION);
 869                         break;
 870                 case Opt_journal_update:
 871                         /* @@@ FIXME */
 872                         /* Eventually we will want to be able to create
 873                            a journal file here.  For now, only allow the
 874                            user to specify an existing inode to be the
 875                            journal file. */
 876                         if (is_remount) {
 877                                 printk(KERN_ERR "EXT4-fs: cannot specify "
 878                                        "journal on remount\n");
 879                                 return 0;
 880                         }
 881                         set_opt (sbi->s_mount_opt, UPDATE_JOURNAL);
 882                         break;
 883                 case Opt_journal_inum:
 884                         if (is_remount) {
 885                                 printk(KERN_ERR "EXT4-fs: cannot specify "
 886                                        "journal on remount\n");
 887                                 return 0;
 888                         }
 889                         if (match_int(&args[0], &option))
 890                                 return 0;
 891                         *inum = option;
 892                         break;
 893                 case Opt_journal_dev:
 894                         if (is_remount) {
 895                                 printk(KERN_ERR "EXT4-fs: cannot specify "
 896                                        "journal on remount\n");
 897                                 return 0;
 898                         }
 899                         if (match_int(&args[0], &option))
 900                                 return 0;
 901                         *journal_devnum = option;
 902                         break;
 903                 case Opt_noload:
 904                         set_opt (sbi->s_mount_opt, NOLOAD);
 905                         break;
 906                 case Opt_commit:
 907                         if (match_int(&args[0], &option))
 908                                 return 0;
 909                         if (option < 0)
 910                                 return 0;
 911                         if (option == 0)
 912                                 option = JBD_DEFAULT_MAX_COMMIT_AGE;
 913                         sbi->s_commit_interval = HZ * option;
 914                         break;
 915                 case Opt_data_journal:
 916                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
 917                         goto datacheck;
 918                 case Opt_data_ordered:
 919                         data_opt = EXT4_MOUNT_ORDERED_DATA;
 920                         goto datacheck;
 921                 case Opt_data_writeback:
 922                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
 923                 datacheck:
 924                         if (is_remount) {
 925                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
 926                                                 != data_opt) {
 927                                         printk(KERN_ERR
 928                                                 "EXT4-fs: cannot change data "
 929                                                 "mode on remount\n");
 930                                         return 0;
 931                                 }
 932                         } else {
 933                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
 934                                 sbi->s_mount_opt |= data_opt;
 935                         }
 936                         break;
 937 #ifdef CONFIG_QUOTA
 938                 case Opt_usrjquota:
 939                         qtype = USRQUOTA;
 940                         goto set_qf_name;
 941                 case Opt_grpjquota:
 942                         qtype = GRPQUOTA;
 943 set_qf_name:
 944                         if (sb_any_quota_enabled(sb)) {
 945                                 printk(KERN_ERR
 946                                         "EXT4-fs: Cannot change journalled "
 947                                         "quota options when quota turned on.\n");
 948                                 return 0;
 949                         }
 950                         qname = match_strdup(&args[0]);
 951                         if (!qname) {
 952                                 printk(KERN_ERR
 953                                         "EXT4-fs: not enough memory for "
 954                                         "storing quotafile name.\n");
 955                                 return 0;
 956                         }
 957                         if (sbi->s_qf_names[qtype] &&
 958                             strcmp(sbi->s_qf_names[qtype], qname)) {
 959                                 printk(KERN_ERR
 960                                         "EXT4-fs: %s quota file already "
 961                                         "specified.\n", QTYPE2NAME(qtype));
 962                                 kfree(qname);
 963                                 return 0;
 964                         }
 965                         sbi->s_qf_names[qtype] = qname;
 966                         if (strchr(sbi->s_qf_names[qtype], '/')) {
 967                                 printk(KERN_ERR
 968                                         "EXT4-fs: quotafile must be on "
 969                                         "filesystem root.\n");
 970                                 kfree(sbi->s_qf_names[qtype]);
 971                                 sbi->s_qf_names[qtype] = NULL;
 972                                 return 0;
 973                         }
 974                         set_opt(sbi->s_mount_opt, QUOTA);
 975                         break;
 976                 case Opt_offusrjquota:
 977                         qtype = USRQUOTA;
 978                         goto clear_qf_name;
 979                 case Opt_offgrpjquota:
 980                         qtype = GRPQUOTA;
 981 clear_qf_name:
 982                         if (sb_any_quota_enabled(sb)) {
 983                                 printk(KERN_ERR "EXT4-fs: Cannot change "
 984                                         "journalled quota options when "
 985                                         "quota turned on.\n");
 986                                 return 0;
 987                         }
 988                         /*
 989                          * The space will be released later when all options
 990                          * are confirmed to be correct
 991                          */
 992                         sbi->s_qf_names[qtype] = NULL;
 993                         break;
 994                 case Opt_jqfmt_vfsold:
 995                         sbi->s_jquota_fmt = QFMT_VFS_OLD;
 996                         break;
 997                 case Opt_jqfmt_vfsv0:
 998                         sbi->s_jquota_fmt = QFMT_VFS_V0;
 999                         break;
1000                 case Opt_quota:
1001                 case Opt_usrquota:
1002                         set_opt(sbi->s_mount_opt, QUOTA);
1003                         set_opt(sbi->s_mount_opt, USRQUOTA);
1004                         break;
1005                 case Opt_grpquota:
1006                         set_opt(sbi->s_mount_opt, QUOTA);
1007                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1008                         break;
1009                 case Opt_noquota:
1010                         if (sb_any_quota_enabled(sb)) {
1011                                 printk(KERN_ERR "EXT4-fs: Cannot change quota "
1012                                         "options when quota turned on.\n");
1013                                 return 0;
1014                         }
1015                         clear_opt(sbi->s_mount_opt, QUOTA);
1016                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1017                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1018                         break;
1019 #else
1020                 case Opt_quota:
1021                 case Opt_usrquota:
1022                 case Opt_grpquota:
1023                 case Opt_usrjquota:
1024                 case Opt_grpjquota:
1025                 case Opt_offusrjquota:
1026                 case Opt_offgrpjquota:
1027                 case Opt_jqfmt_vfsold:
1028                 case Opt_jqfmt_vfsv0:
1029                         printk(KERN_ERR
1030                                 "EXT4-fs: journalled quota options not "
1031                                 "supported.\n");
1032                         break;
1033                 case Opt_noquota:
1034                         break;
1035 #endif
1036                 case Opt_abort:
1037                         set_opt(sbi->s_mount_opt, ABORT);
1038                         break;
1039                 case Opt_barrier:
1040                         if (match_int(&args[0], &option))
1041                                 return 0;
1042                         if (option)
1043                                 set_opt(sbi->s_mount_opt, BARRIER);
1044                         else
1045                                 clear_opt(sbi->s_mount_opt, BARRIER);
1046                         break;
1047                 case Opt_ignore:
1048                         break;
1049                 case Opt_resize:
1050                         if (!is_remount) {
1051                                 printk("EXT4-fs: resize option only available "
1052                                         "for remount\n");
1053                                 return 0;
1054                         }
1055                         if (match_int(&args[0], &option) != 0)
1056                                 return 0;
1057                         *n_blocks_count = option;
1058                         break;
1059                 case Opt_nobh:
1060                         set_opt(sbi->s_mount_opt, NOBH);
1061                         break;
1062                 case Opt_bh:
1063                         clear_opt(sbi->s_mount_opt, NOBH);
1064                         break;
1065                 case Opt_extents:
1066                         set_opt (sbi->s_mount_opt, EXTENTS);
1067                         break;
1068                 default:
1069                         printk (KERN_ERR
1070                                 "EXT4-fs: Unrecognized mount option \"%s\" "
1071                                 "or missing value\n", p);
1072                         return 0;
1073                 }
1074         }
1075 #ifdef CONFIG_QUOTA
1076         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1077                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1078                      sbi->s_qf_names[USRQUOTA])
1079                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1080
1081                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1082                      sbi->s_qf_names[GRPQUOTA])
1083                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1084
1085                 if ((sbi->s_qf_names[USRQUOTA] &&
1086                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1087                     (sbi->s_qf_names[GRPQUOTA] &&
1088                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1089                         printk(KERN_ERR "EXT4-fs: old and new quota "
1090                                         "format mixing.\n");
1091                         return 0;
1092                 }
1093
1094                 if (!sbi->s_jquota_fmt) {
1095                         printk(KERN_ERR "EXT4-fs: journalled quota format "
1096                                         "not specified.\n");
1097                         return 0;
1098                 }
1099         } else {
1100                 if (sbi->s_jquota_fmt) {
1101                         printk(KERN_ERR "EXT4-fs: journalled quota format "
1102                                         "specified with no journalling "
1103                                         "enabled.\n");
1104                         return 0;
1105                 }
1106         }
1107 #endif
1108         return 1;
1109 }
1110
1111 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1112                             int read_only)
1113 {
1114         struct ext4_sb_info *sbi = EXT4_SB(sb);
1115         int res = 0;
1116
1117         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1118                 printk (KERN_ERR "EXT4-fs warning: revision level too high, "
1119                         "forcing read-only mode\n");
1120                 res = MS_RDONLY;
1121         }
1122         if (read_only)
1123                 return res;
1124         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1125                 printk (KERN_WARNING "EXT4-fs warning: mounting unchecked fs, "
1126                         "running e2fsck is recommended\n");
1127         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1128                 printk (KERN_WARNING
1129                         "EXT4-fs warning: mounting fs with errors, "
1130                         "running e2fsck is recommended\n");
1131         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1132                  le16_to_cpu(es->s_mnt_count) >=
1133                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1134                 printk (KERN_WARNING
1135                         "EXT4-fs warning: maximal mount count reached, "
1136                         "running e2fsck is recommended\n");
1137         else if (le32_to_cpu(es->s_checkinterval) &&
1138                 (le32_to_cpu(es->s_lastcheck) +
1139                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1140                 printk (KERN_WARNING
1141                         "EXT4-fs warning: checktime reached, "
1142                         "running e2fsck is recommended\n");
1143 #if 0
1144                 /* @@@ We _will_ want to clear the valid bit if we find
1145                    inconsistencies, to force a fsck at reboot.  But for
1146                    a plain journaled filesystem we can keep it set as
1147                    valid forever! :) */
1148         es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & ~EXT4_VALID_FS);
1149 #endif
1150         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1151                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1152         es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
1153         es->s_mtime = cpu_to_le32(get_seconds());
1154         ext4_update_dynamic_rev(sb);
1155         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1156
1157         ext4_commit_super(sb, es, 1);
1158         if (test_opt(sb, DEBUG))
1159                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%lu, "
1160                                 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
1161                         sb->s_blocksize,
1162                         sbi->s_groups_count,
1163                         EXT4_BLOCKS_PER_GROUP(sb),
1164                         EXT4_INODES_PER_GROUP(sb),
1165                         sbi->s_mount_opt);
1166
1167         printk(KERN_INFO "EXT4 FS on %s, ", sb->s_id);
1168         if (EXT4_SB(sb)->s_journal->j_inode == NULL) {
1169                 char b[BDEVNAME_SIZE];
1170
1171                 printk("external journal on %s\n",
1172                         bdevname(EXT4_SB(sb)->s_journal->j_dev, b));
1173         } else {
1174                 printk("internal journal\n");
1175         }
1176         return res;
1177 }
1178
1179 /* Called at mount-time, super-block is locked */
1180 static int ext4_check_descriptors (struct super_block * sb)
1181 {
1182         struct ext4_sb_info *sbi = EXT4_SB(sb);
1183         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1184         ext4_fsblk_t last_block;
1185         struct ext4_group_desc * gdp = NULL;
1186         int desc_block = 0;
1187         int i;
1188
1189         ext4_debug ("Checking group descriptors");
1190
1191         for (i = 0; i < sbi->s_groups_count; i++)
1192         {
1193                 if (i == sbi->s_groups_count - 1)
1194                         last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
1195                 else
1196                         last_block = first_block +
1197                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1198
1199                 if ((i % EXT4_DESC_PER_BLOCK(sb)) == 0)
1200                         gdp = (struct ext4_group_desc *)
1201                                         sbi->s_group_desc[desc_block++]->b_data;
1202                 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
1203                     le32_to_cpu(gdp->bg_block_bitmap) > last_block)
1204                 {
1205                         ext4_error (sb, "ext4_check_descriptors",
1206                                     "Block bitmap for group %d"
1207                                     " not in group (block %lu)!",
1208                                     i, (unsigned long)
1209                                         le32_to_cpu(gdp->bg_block_bitmap));
1210                         return 0;
1211                 }
1212                 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
1213                     le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
1214                 {
1215                         ext4_error (sb, "ext4_check_descriptors",
1216                                     "Inode bitmap for group %d"
1217                                     " not in group (block %lu)!",
1218                                     i, (unsigned long)
1219                                         le32_to_cpu(gdp->bg_inode_bitmap));
1220                         return 0;
1221                 }
1222                 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
1223                     le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >
1224                     last_block)
1225                 {
1226                         ext4_error (sb, "ext4_check_descriptors",
1227                                     "Inode table for group %d"
1228                                     " not in group (block %lu)!",
1229                                     i, (unsigned long)
1230                                         le32_to_cpu(gdp->bg_inode_table));
1231                         return 0;
1232                 }
1233                 first_block += EXT4_BLOCKS_PER_GROUP(sb);
1234                 gdp++;
1235         }
1236
1237         sbi->s_es->s_free_blocks_count=cpu_to_le32(ext4_count_free_blocks(sb));
1238         sbi->s_es->s_free_inodes_count=cpu_to_le32(ext4_count_free_inodes(sb));
1239         return 1;
1240 }
1241
1242
1243 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1244  * the superblock) which were deleted from all directories, but held open by
1245  * a process at the time of a crash.  We walk the list and try to delete these
1246  * inodes at recovery time (only with a read-write filesystem).
1247  *
1248  * In order to keep the orphan inode chain consistent during traversal (in
1249  * case of crash during recovery), we link each inode into the superblock
1250  * orphan list_head and handle it the same way as an inode deletion during
1251  * normal operation (which journals the operations for us).
1252  *
1253  * We only do an iget() and an iput() on each inode, which is very safe if we
1254  * accidentally point at an in-use or already deleted inode.  The worst that
1255  * can happen in this case is that we get a "bit already cleared" message from
1256  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1257  * e2fsck was run on this filesystem, and it must have already done the orphan
1258  * inode cleanup for us, so we can safely abort without any further action.
1259  */
1260 static void ext4_orphan_cleanup (struct super_block * sb,
1261                                  struct ext4_super_block * es)
1262 {
1263         unsigned int s_flags = sb->s_flags;
1264         int nr_orphans = 0, nr_truncates = 0;
1265 #ifdef CONFIG_QUOTA
1266         int i;
1267 #endif
1268         if (!es->s_last_orphan) {
1269                 jbd_debug(4, "no orphan inodes to clean up\n");
1270                 return;
1271         }
1272
1273         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1274                 if (es->s_last_orphan)
1275                         jbd_debug(1, "Errors on filesystem, "
1276                                   "clearing orphan list.\n");
1277                 es->s_last_orphan = 0;
1278                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1279                 return;
1280         }
1281
1282         if (s_flags & MS_RDONLY) {
1283                 printk(KERN_INFO "EXT4-fs: %s: orphan cleanup on readonly fs\n",
1284                        sb->s_id);
1285                 sb->s_flags &= ~MS_RDONLY;
1286         }
1287 #ifdef CONFIG_QUOTA
1288         /* Needed for iput() to work correctly and not trash data */
1289         sb->s_flags |= MS_ACTIVE;
1290         /* Turn on quotas so that they are updated correctly */
1291         for (i = 0; i < MAXQUOTAS; i++) {
1292                 if (EXT4_SB(sb)->s_qf_names[i]) {
1293                         int ret = ext4_quota_on_mount(sb, i);
1294                         if (ret < 0)
1295                                 printk(KERN_ERR
1296                                         "EXT4-fs: Cannot turn on journalled "
1297                                         "quota: error %d\n", ret);
1298                 }
1299         }
1300 #endif
1301
1302         while (es->s_last_orphan) {
1303                 struct inode *inode;
1304
1305                 if (!(inode =
1306                       ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan)))) {
1307                         es->s_last_orphan = 0;
1308                         break;
1309                 }
1310
1311                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1312                 DQUOT_INIT(inode);
1313                 if (inode->i_nlink) {
1314                         printk(KERN_DEBUG
1315                                 "%s: truncating inode %lu to %Ld bytes\n",
1316                                 __FUNCTION__, inode->i_ino, inode->i_size);
1317                         jbd_debug(2, "truncating inode %lu to %Ld bytes\n",
1318                                   inode->i_ino, inode->i_size);
1319                         ext4_truncate(inode);
1320                         nr_truncates++;
1321                 } else {
1322                         printk(KERN_DEBUG
1323                                 "%s: deleting unreferenced inode %lu\n",
1324                                 __FUNCTION__, inode->i_ino);
1325                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1326                                   inode->i_ino);
1327                         nr_orphans++;
1328                 }
1329                 iput(inode);  /* The delete magic happens here! */
1330         }
1331
1332 #define PLURAL(x) (x), ((x)==1) ? "" : "s"
1333
1334         if (nr_orphans)
1335                 printk(KERN_INFO "EXT4-fs: %s: %d orphan inode%s deleted\n",
1336                        sb->s_id, PLURAL(nr_orphans));
1337         if (nr_truncates)
1338                 printk(KERN_INFO "EXT4-fs: %s: %d truncate%s cleaned up\n",
1339                        sb->s_id, PLURAL(nr_truncates));
1340 #ifdef CONFIG_QUOTA
1341         /* Turn quotas off */
1342         for (i = 0; i < MAXQUOTAS; i++) {
1343                 if (sb_dqopt(sb)->files[i])
1344                         vfs_quota_off(sb, i);
1345         }
1346 #endif
1347         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1348 }
1349
1350 #define log2(n) ffz(~(n))
1351
1352 /*
1353  * Maximal file size.  There is a direct, and {,double-,triple-}indirect
1354  * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
1355  * We need to be 1 filesystem block less than the 2^32 sector limit.
1356  */
1357 static loff_t ext4_max_size(int bits)
1358 {
1359         loff_t res = EXT4_NDIR_BLOCKS;
1360         /* This constant is calculated to be the largest file size for a
1361          * dense, 4k-blocksize file such that the total number of
1362          * sectors in the file, including data and all indirect blocks,
1363          * does not exceed 2^32. */
1364         const loff_t upper_limit = 0x1ff7fffd000LL;
1365
1366         res += 1LL << (bits-2);
1367         res += 1LL << (2*(bits-2));
1368         res += 1LL << (3*(bits-2));
1369         res <<= bits;
1370         if (res > upper_limit)
1371                 res = upper_limit;
1372         return res;
1373 }
1374
1375 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
1376                                     ext4_fsblk_t logic_sb_block,
1377                                     int nr)
1378 {
1379         struct ext4_sb_info *sbi = EXT4_SB(sb);
1380         unsigned long bg, first_meta_bg;
1381         int has_super = 0;
1382
1383         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
1384
1385         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
1386             nr < first_meta_bg)
1387                 return (logic_sb_block + nr + 1);
1388         bg = sbi->s_desc_per_block * nr;
1389         if (ext4_bg_has_super(sb, bg))
1390                 has_super = 1;
1391         return (has_super + ext4_group_first_block_no(sb, bg));
1392 }
1393
1394
1395 static int ext4_fill_super (struct super_block *sb, void *data, int silent)
1396 {
1397         struct buffer_head * bh;
1398         struct ext4_super_block *es = NULL;
1399         struct ext4_sb_info *sbi;
1400         ext4_fsblk_t block;
1401         ext4_fsblk_t sb_block = get_sb_block(&data);
1402         ext4_fsblk_t logic_sb_block;
1403         unsigned long offset = 0;
1404         unsigned int journal_inum = 0;
1405         unsigned long journal_devnum = 0;
1406         unsigned long def_mount_opts;
1407         struct inode *root;
1408         int blocksize;
1409         int hblock;
1410         int db_count;
1411         int i;
1412         int needs_recovery;
1413         __le32 features;
1414
1415         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
1416         if (!sbi)
1417                 return -ENOMEM;
1418         sb->s_fs_info = sbi;
1419         sbi->s_mount_opt = 0;
1420         sbi->s_resuid = EXT4_DEF_RESUID;
1421         sbi->s_resgid = EXT4_DEF_RESGID;
1422
1423         unlock_kernel();
1424
1425         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
1426         if (!blocksize) {
1427                 printk(KERN_ERR "EXT4-fs: unable to set blocksize\n");
1428                 goto out_fail;
1429         }
1430
1431         /*
1432          * The ext4 superblock will not be buffer aligned for other than 1kB
1433          * block sizes.  We need to calculate the offset from buffer start.
1434          */
1435         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
1436                 logic_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
1437                 offset = sector_div(logic_sb_block, blocksize);
1438         } else {
1439                 logic_sb_block = sb_block;
1440         }
1441
1442         if (!(bh = sb_bread(sb, logic_sb_block))) {
1443                 printk (KERN_ERR "EXT4-fs: unable to read superblock\n");
1444                 goto out_fail;
1445         }
1446         /*
1447          * Note: s_es must be initialized as soon as possible because
1448          *       some ext4 macro-instructions depend on its value
1449          */
1450         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
1451         sbi->s_es = es;
1452         sb->s_magic = le16_to_cpu(es->s_magic);
1453         if (sb->s_magic != EXT4_SUPER_MAGIC)
1454                 goto cantfind_ext4;
1455
1456         /* Set defaults before we parse the mount options */
1457         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
1458         if (def_mount_opts & EXT4_DEFM_DEBUG)
1459                 set_opt(sbi->s_mount_opt, DEBUG);
1460         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
1461                 set_opt(sbi->s_mount_opt, GRPID);
1462         if (def_mount_opts & EXT4_DEFM_UID16)
1463                 set_opt(sbi->s_mount_opt, NO_UID32);
1464         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
1465                 set_opt(sbi->s_mount_opt, XATTR_USER);
1466         if (def_mount_opts & EXT4_DEFM_ACL)
1467                 set_opt(sbi->s_mount_opt, POSIX_ACL);
1468         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
1469                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
1470         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
1471                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
1472         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
1473                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
1474
1475         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
1476                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1477         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_RO)
1478                 set_opt(sbi->s_mount_opt, ERRORS_RO);
1479
1480         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
1481         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
1482
1483         set_opt(sbi->s_mount_opt, RESERVATION);
1484
1485         if (!parse_options ((char *) data, sb, &journal_inum, &journal_devnum,
1486                             NULL, 0))
1487                 goto failed_mount;
1488
1489         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1490                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1491
1492         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
1493             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
1494              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
1495              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
1496                 printk(KERN_WARNING
1497                        "EXT4-fs warning: feature flags set on rev 0 fs, "
1498                        "running e2fsck is recommended\n");
1499         /*
1500          * Check feature flags regardless of the revision level, since we
1501          * previously didn't change the revision level when setting the flags,
1502          * so there is a chance incompat flags are set on a rev 0 filesystem.
1503          */
1504         features = EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP);
1505         if (features) {
1506                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount because of "
1507                        "unsupported optional features (%x).\n",
1508                        sb->s_id, le32_to_cpu(features));
1509                 goto failed_mount;
1510         }
1511         features = EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP);
1512         if (!(sb->s_flags & MS_RDONLY) && features) {
1513                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount RDWR because of "
1514                        "unsupported optional features (%x).\n",
1515                        sb->s_id, le32_to_cpu(features));
1516                 goto failed_mount;
1517         }
1518         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
1519
1520         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
1521             blocksize > EXT4_MAX_BLOCK_SIZE) {
1522                 printk(KERN_ERR
1523                        "EXT4-fs: Unsupported filesystem blocksize %d on %s.\n",
1524                        blocksize, sb->s_id);
1525                 goto failed_mount;
1526         }
1527
1528         hblock = bdev_hardsect_size(sb->s_bdev);
1529         if (sb->s_blocksize != blocksize) {
1530                 /*
1531                  * Make sure the blocksize for the filesystem is larger
1532                  * than the hardware sectorsize for the machine.
1533                  */
1534                 if (blocksize < hblock) {
1535                         printk(KERN_ERR "EXT4-fs: blocksize %d too small for "
1536                                "device blocksize %d.\n", blocksize, hblock);
1537                         goto failed_mount;
1538                 }
1539
1540                 brelse (bh);
1541                 sb_set_blocksize(sb, blocksize);
1542                 logic_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
1543                 offset = sector_div(logic_sb_block, blocksize);
1544                 bh = sb_bread(sb, logic_sb_block);
1545                 if (!bh) {
1546                         printk(KERN_ERR
1547                                "EXT4-fs: Can't read superblock on 2nd try.\n");
1548                         goto failed_mount;
1549                 }
1550                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
1551                 sbi->s_es = es;
1552                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
1553                         printk (KERN_ERR
1554                                 "EXT4-fs: Magic mismatch, very weird !\n");
1555                         goto failed_mount;
1556                 }
1557         }
1558
1559         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits);
1560
1561         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
1562                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
1563                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
1564         } else {
1565                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
1566                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
1567                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
1568                     (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
1569                     (sbi->s_inode_size > blocksize)) {
1570                         printk (KERN_ERR
1571                                 "EXT4-fs: unsupported inode size: %d\n",
1572                                 sbi->s_inode_size);
1573                         goto failed_mount;
1574                 }
1575         }
1576         sbi->s_frag_size = EXT4_MIN_FRAG_SIZE <<
1577                                    le32_to_cpu(es->s_log_frag_size);
1578         if (blocksize != sbi->s_frag_size) {
1579                 printk(KERN_ERR
1580                        "EXT4-fs: fragsize %lu != blocksize %u (unsupported)\n",
1581                        sbi->s_frag_size, blocksize);
1582                 goto failed_mount;
1583         }
1584         sbi->s_frags_per_block = 1;
1585         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
1586         sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
1587         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
1588         if (EXT4_INODE_SIZE(sb) == 0)
1589                 goto cantfind_ext4;
1590         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
1591         if (sbi->s_inodes_per_block == 0)
1592                 goto cantfind_ext4;
1593         sbi->s_itb_per_group = sbi->s_inodes_per_group /
1594                                         sbi->s_inodes_per_block;
1595         sbi->s_desc_per_block = blocksize / sizeof(struct ext4_group_desc);
1596         sbi->s_sbh = bh;
1597         sbi->s_mount_state = le16_to_cpu(es->s_state);
1598         sbi->s_addr_per_block_bits = log2(EXT4_ADDR_PER_BLOCK(sb));
1599         sbi->s_desc_per_block_bits = log2(EXT4_DESC_PER_BLOCK(sb));
1600         for (i=0; i < 4; i++)
1601                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
1602         sbi->s_def_hash_version = es->s_def_hash_version;
1603
1604         if (sbi->s_blocks_per_group > blocksize * 8) {
1605                 printk (KERN_ERR
1606                         "EXT4-fs: #blocks per group too big: %lu\n",
1607                         sbi->s_blocks_per_group);
1608                 goto failed_mount;
1609         }
1610         if (sbi->s_frags_per_group > blocksize * 8) {
1611                 printk (KERN_ERR
1612                         "EXT4-fs: #fragments per group too big: %lu\n",
1613                         sbi->s_frags_per_group);
1614                 goto failed_mount;
1615         }
1616         if (sbi->s_inodes_per_group > blocksize * 8) {
1617                 printk (KERN_ERR
1618                         "EXT4-fs: #inodes per group too big: %lu\n",
1619                         sbi->s_inodes_per_group);
1620                 goto failed_mount;
1621         }
1622
1623         if (le32_to_cpu(es->s_blocks_count) >
1624                     (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
1625                 printk(KERN_ERR "EXT4-fs: filesystem on %s:"
1626                         " too large to mount safely\n", sb->s_id);
1627                 if (sizeof(sector_t) < 8)
1628                         printk(KERN_WARNING "EXT4-fs: CONFIG_LBD not "
1629                                         "enabled\n");
1630                 goto failed_mount;
1631         }
1632
1633         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
1634                 goto cantfind_ext4;
1635         sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
1636                                le32_to_cpu(es->s_first_data_block) - 1)
1637                                        / EXT4_BLOCKS_PER_GROUP(sb)) + 1;
1638         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
1639                    EXT4_DESC_PER_BLOCK(sb);
1640         sbi->s_group_desc = kmalloc(db_count * sizeof (struct buffer_head *),
1641                                     GFP_KERNEL);
1642         if (sbi->s_group_desc == NULL) {
1643                 printk (KERN_ERR "EXT4-fs: not enough memory\n");
1644                 goto failed_mount;
1645         }
1646
1647         bgl_lock_init(&sbi->s_blockgroup_lock);
1648
1649         for (i = 0; i < db_count; i++) {
1650                 block = descriptor_loc(sb, logic_sb_block, i);
1651                 sbi->s_group_desc[i] = sb_bread(sb, block);
1652                 if (!sbi->s_group_desc[i]) {
1653                         printk (KERN_ERR "EXT4-fs: "
1654                                 "can't read group descriptor %d\n", i);
1655                         db_count = i;
1656                         goto failed_mount2;
1657                 }
1658         }
1659         if (!ext4_check_descriptors (sb)) {
1660                 printk(KERN_ERR "EXT4-fs: group descriptors corrupted!\n");
1661                 goto failed_mount2;
1662         }
1663         sbi->s_gdb_count = db_count;
1664         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1665         spin_lock_init(&sbi->s_next_gen_lock);
1666
1667         percpu_counter_init(&sbi->s_freeblocks_counter,
1668                 ext4_count_free_blocks(sb));
1669         percpu_counter_init(&sbi->s_freeinodes_counter,
1670                 ext4_count_free_inodes(sb));
1671         percpu_counter_init(&sbi->s_dirs_counter,
1672                 ext4_count_dirs(sb));
1673
1674         /* per fileystem reservation list head & lock */
1675         spin_lock_init(&sbi->s_rsv_window_lock);
1676         sbi->s_rsv_window_root = RB_ROOT;
1677         /* Add a single, static dummy reservation to the start of the
1678          * reservation window list --- it gives us a placeholder for
1679          * append-at-start-of-list which makes the allocation logic
1680          * _much_ simpler. */
1681         sbi->s_rsv_window_head.rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
1682         sbi->s_rsv_window_head.rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
1683         sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1684         sbi->s_rsv_window_head.rsv_goal_size = 0;
1685         ext4_rsv_window_add(sb, &sbi->s_rsv_window_head);
1686
1687         /*
1688          * set up enough so that it can read an inode
1689          */
1690         sb->s_op = &ext4_sops;
1691         sb->s_export_op = &ext4_export_ops;
1692         sb->s_xattr = ext4_xattr_handlers;
1693 #ifdef CONFIG_QUOTA
1694         sb->s_qcop = &ext4_qctl_operations;
1695         sb->dq_op = &ext4_quota_operations;
1696 #endif
1697         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
1698
1699         sb->s_root = NULL;
1700
1701         needs_recovery = (es->s_last_orphan != 0 ||
1702                           EXT4_HAS_INCOMPAT_FEATURE(sb,
1703                                     EXT4_FEATURE_INCOMPAT_RECOVER));
1704
1705         /*
1706          * The first inode we look at is the journal inode.  Don't try
1707          * root first: it may be modified in the journal!
1708          */
1709         if (!test_opt(sb, NOLOAD) &&
1710             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
1711                 if (ext4_load_journal(sb, es, journal_devnum))
1712                         goto failed_mount3;
1713         } else if (journal_inum) {
1714                 if (ext4_create_journal(sb, es, journal_inum))
1715                         goto failed_mount3;
1716         } else {
1717                 if (!silent)
1718                         printk (KERN_ERR
1719                                 "ext4: No journal on filesystem on %s\n",
1720                                 sb->s_id);
1721                 goto failed_mount3;
1722         }
1723
1724         /* We have now updated the journal if required, so we can
1725          * validate the data journaling mode. */
1726         switch (test_opt(sb, DATA_FLAGS)) {
1727         case 0:
1728                 /* No mode set, assume a default based on the journal
1729                    capabilities: ORDERED_DATA if the journal can
1730                    cope, else JOURNAL_DATA */
1731                 if (jbd2_journal_check_available_features
1732                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
1733                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
1734                 else
1735                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
1736                 break;
1737
1738         case EXT4_MOUNT_ORDERED_DATA:
1739         case EXT4_MOUNT_WRITEBACK_DATA:
1740                 if (!jbd2_journal_check_available_features
1741                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
1742                         printk(KERN_ERR "EXT4-fs: Journal does not support "
1743                                "requested data journaling mode\n");
1744                         goto failed_mount4;
1745                 }
1746         default:
1747                 break;
1748         }
1749
1750         if (test_opt(sb, NOBH)) {
1751                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
1752                         printk(KERN_WARNING "EXT4-fs: Ignoring nobh option - "
1753                                 "its supported only with writeback mode\n");
1754                         clear_opt(sbi->s_mount_opt, NOBH);
1755                 }
1756         }
1757         /*
1758          * The jbd2_journal_load will have done any necessary log recovery,
1759          * so we can safely mount the rest of the filesystem now.
1760          */
1761
1762         root = iget(sb, EXT4_ROOT_INO);
1763         sb->s_root = d_alloc_root(root);
1764         if (!sb->s_root) {
1765                 printk(KERN_ERR "EXT4-fs: get root inode failed\n");
1766                 iput(root);
1767                 goto failed_mount4;
1768         }
1769         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1770                 dput(sb->s_root);
1771                 sb->s_root = NULL;
1772                 printk(KERN_ERR "EXT4-fs: corrupt root inode, run e2fsck\n");
1773                 goto failed_mount4;
1774         }
1775
1776         ext4_setup_super (sb, es, sb->s_flags & MS_RDONLY);
1777         /*
1778          * akpm: core read_super() calls in here with the superblock locked.
1779          * That deadlocks, because orphan cleanup needs to lock the superblock
1780          * in numerous places.  Here we just pop the lock - it's relatively
1781          * harmless, because we are now ready to accept write_super() requests,
1782          * and aviro says that's the only reason for hanging onto the
1783          * superblock lock.
1784          */
1785         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
1786         ext4_orphan_cleanup(sb, es);
1787         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
1788         if (needs_recovery)
1789                 printk (KERN_INFO "EXT4-fs: recovery complete.\n");
1790         ext4_mark_recovery_complete(sb, es);
1791         printk (KERN_INFO "EXT4-fs: mounted filesystem with %s data mode.\n",
1792                 test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ? "journal":
1793                 test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA ? "ordered":
1794                 "writeback");
1795
1796         ext4_ext_init(sb);
1797
1798         lock_kernel();
1799         return 0;
1800
1801 cantfind_ext4:
1802         if (!silent)
1803                 printk(KERN_ERR "VFS: Can't find ext4 filesystem on dev %s.\n",
1804                        sb->s_id);
1805         goto failed_mount;
1806
1807 failed_mount4:
1808         jbd2_journal_destroy(sbi->s_journal);
1809 failed_mount3:
1810         percpu_counter_destroy(&sbi->s_freeblocks_counter);
1811         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1812         percpu_counter_destroy(&sbi->s_dirs_counter);
1813 failed_mount2:
1814         for (i = 0; i < db_count; i++)
1815                 brelse(sbi->s_group_desc[i]);
1816         kfree(sbi->s_group_desc);
1817 failed_mount:
1818 #ifdef CONFIG_QUOTA
1819         for (i = 0; i < MAXQUOTAS; i++)
1820                 kfree(sbi->s_qf_names[i]);
1821 #endif
1822         ext4_blkdev_remove(sbi);
1823         brelse(bh);
1824 out_fail:
1825         sb->s_fs_info = NULL;
1826         kfree(sbi);
1827         lock_kernel();
1828         return -EINVAL;
1829 }
1830
1831 /*
1832  * Setup any per-fs journal parameters now.  We'll do this both on
1833  * initial mount, once the journal has been initialised but before we've
1834  * done any recovery; and again on any subsequent remount.
1835  */
1836 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
1837 {
1838         struct ext4_sb_info *sbi = EXT4_SB(sb);
1839
1840         if (sbi->s_commit_interval)
1841                 journal->j_commit_interval = sbi->s_commit_interval;
1842         /* We could also set up an ext4-specific default for the commit
1843          * interval here, but for now we'll just fall back to the jbd
1844          * default. */
1845
1846         spin_lock(&journal->j_state_lock);
1847         if (test_opt(sb, BARRIER))
1848                 journal->j_flags |= JBD2_BARRIER;
1849         else
1850                 journal->j_flags &= ~JBD2_BARRIER;
1851         spin_unlock(&journal->j_state_lock);
1852 }
1853
1854 static journal_t *ext4_get_journal(struct super_block *sb,
1855                                    unsigned int journal_inum)
1856 {
1857         struct inode *journal_inode;
1858         journal_t *journal;
1859
1860         /* First, test for the existence of a valid inode on disk.  Bad
1861          * things happen if we iget() an unused inode, as the subsequent
1862          * iput() will try to delete it. */
1863
1864         journal_inode = iget(sb, journal_inum);
1865         if (!journal_inode) {
1866                 printk(KERN_ERR "EXT4-fs: no journal found.\n");
1867                 return NULL;
1868         }
1869         if (!journal_inode->i_nlink) {
1870                 make_bad_inode(journal_inode);
1871                 iput(journal_inode);
1872                 printk(KERN_ERR "EXT4-fs: journal inode is deleted.\n");
1873                 return NULL;
1874         }
1875
1876         jbd_debug(2, "Journal inode found at %p: %Ld bytes\n",
1877                   journal_inode, journal_inode->i_size);
1878         if (is_bad_inode(journal_inode) || !S_ISREG(journal_inode->i_mode)) {
1879                 printk(KERN_ERR "EXT4-fs: invalid journal inode.\n");
1880                 iput(journal_inode);
1881                 return NULL;
1882         }
1883
1884         journal = jbd2_journal_init_inode(journal_inode);
1885         if (!journal) {
1886                 printk(KERN_ERR "EXT4-fs: Could not load journal inode\n");
1887                 iput(journal_inode);
1888                 return NULL;
1889         }
1890         journal->j_private = sb;
1891         ext4_init_journal_params(sb, journal);
1892         return journal;
1893 }
1894
1895 static journal_t *ext4_get_dev_journal(struct super_block *sb,
1896                                        dev_t j_dev)
1897 {
1898         struct buffer_head * bh;
1899         journal_t *journal;
1900         ext4_fsblk_t start;
1901         ext4_fsblk_t len;
1902         int hblock, blocksize;
1903         ext4_fsblk_t sb_block;
1904         unsigned long offset;
1905         struct ext4_super_block * es;
1906         struct block_device *bdev;
1907
1908         bdev = ext4_blkdev_get(j_dev);
1909         if (bdev == NULL)
1910                 return NULL;
1911
1912         if (bd_claim(bdev, sb)) {
1913                 printk(KERN_ERR
1914                         "EXT4: failed to claim external journal device.\n");
1915                 blkdev_put(bdev);
1916                 return NULL;
1917         }
1918
1919         blocksize = sb->s_blocksize;
1920         hblock = bdev_hardsect_size(bdev);
1921         if (blocksize < hblock) {
1922                 printk(KERN_ERR
1923                         "EXT4-fs: blocksize too small for journal device.\n");
1924                 goto out_bdev;
1925         }
1926
1927         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
1928         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
1929         set_blocksize(bdev, blocksize);
1930         if (!(bh = __bread(bdev, sb_block, blocksize))) {
1931                 printk(KERN_ERR "EXT4-fs: couldn't read superblock of "
1932                        "external journal\n");
1933                 goto out_bdev;
1934         }
1935
1936         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
1937         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
1938             !(le32_to_cpu(es->s_feature_incompat) &
1939               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
1940                 printk(KERN_ERR "EXT4-fs: external journal has "
1941                                         "bad superblock\n");
1942                 brelse(bh);
1943                 goto out_bdev;
1944         }
1945
1946         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
1947                 printk(KERN_ERR "EXT4-fs: journal UUID does not match\n");
1948                 brelse(bh);
1949                 goto out_bdev;
1950         }
1951
1952         len = le32_to_cpu(es->s_blocks_count);
1953         start = sb_block + 1;
1954         brelse(bh);     /* we're done with the superblock */
1955
1956         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
1957                                         start, len, blocksize);
1958         if (!journal) {
1959                 printk(KERN_ERR "EXT4-fs: failed to create device journal\n");
1960                 goto out_bdev;
1961         }
1962         journal->j_private = sb;
1963         ll_rw_block(READ, 1, &journal->j_sb_buffer);
1964         wait_on_buffer(journal->j_sb_buffer);
1965         if (!buffer_uptodate(journal->j_sb_buffer)) {
1966                 printk(KERN_ERR "EXT4-fs: I/O error on journal device\n");
1967                 goto out_journal;
1968         }
1969         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
1970                 printk(KERN_ERR "EXT4-fs: External journal has more than one "
1971                                         "user (unsupported) - %d\n",
1972                         be32_to_cpu(journal->j_superblock->s_nr_users));
1973                 goto out_journal;
1974         }
1975         EXT4_SB(sb)->journal_bdev = bdev;
1976         ext4_init_journal_params(sb, journal);
1977         return journal;
1978 out_journal:
1979         jbd2_journal_destroy(journal);
1980 out_bdev:
1981         ext4_blkdev_put(bdev);
1982         return NULL;
1983 }
1984
1985 static int ext4_load_journal(struct super_block *sb,
1986                              struct ext4_super_block *es,
1987                              unsigned long journal_devnum)
1988 {
1989         journal_t *journal;
1990         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
1991         dev_t journal_dev;
1992         int err = 0;
1993         int really_read_only;
1994
1995         if (journal_devnum &&
1996             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
1997                 printk(KERN_INFO "EXT4-fs: external journal device major/minor "
1998                         "numbers have changed\n");
1999                 journal_dev = new_decode_dev(journal_devnum);
2000         } else
2001                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
2002
2003         really_read_only = bdev_read_only(sb->s_bdev);
2004
2005         /*
2006          * Are we loading a blank journal or performing recovery after a
2007          * crash?  For recovery, we need to check in advance whether we
2008          * can get read-write access to the device.
2009          */
2010
2011         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2012                 if (sb->s_flags & MS_RDONLY) {
2013                         printk(KERN_INFO "EXT4-fs: INFO: recovery "
2014                                         "required on readonly filesystem.\n");
2015                         if (really_read_only) {
2016                                 printk(KERN_ERR "EXT4-fs: write access "
2017                                         "unavailable, cannot proceed.\n");
2018                                 return -EROFS;
2019                         }
2020                         printk (KERN_INFO "EXT4-fs: write access will "
2021                                         "be enabled during recovery.\n");
2022                 }
2023         }
2024
2025         if (journal_inum && journal_dev) {
2026                 printk(KERN_ERR "EXT4-fs: filesystem has both journal "
2027                        "and inode journals!\n");
2028                 return -EINVAL;
2029         }
2030
2031         if (journal_inum) {
2032                 if (!(journal = ext4_get_journal(sb, journal_inum)))
2033                         return -EINVAL;
2034         } else {
2035                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
2036                         return -EINVAL;
2037         }
2038
2039         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
2040                 err = jbd2_journal_update_format(journal);
2041                 if (err)  {
2042                         printk(KERN_ERR "EXT4-fs: error updating journal.\n");
2043                         jbd2_journal_destroy(journal);
2044                         return err;
2045                 }
2046         }
2047
2048         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
2049                 err = jbd2_journal_wipe(journal, !really_read_only);
2050         if (!err)
2051                 err = jbd2_journal_load(journal);
2052
2053         if (err) {
2054                 printk(KERN_ERR "EXT4-fs: error loading journal.\n");
2055                 jbd2_journal_destroy(journal);
2056                 return err;
2057         }
2058
2059         EXT4_SB(sb)->s_journal = journal;
2060         ext4_clear_journal_err(sb, es);
2061
2062         if (journal_devnum &&
2063             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2064                 es->s_journal_dev = cpu_to_le32(journal_devnum);
2065                 sb->s_dirt = 1;
2066
2067                 /* Make sure we flush the recovery flag to disk. */
2068                 ext4_commit_super(sb, es, 1);
2069         }
2070
2071         return 0;
2072 }
2073
2074 static int ext4_create_journal(struct super_block * sb,
2075                                struct ext4_super_block * es,
2076                                unsigned int journal_inum)
2077 {
2078         journal_t *journal;
2079
2080         if (sb->s_flags & MS_RDONLY) {
2081                 printk(KERN_ERR "EXT4-fs: readonly filesystem when trying to "
2082                                 "create journal.\n");
2083                 return -EROFS;
2084         }
2085
2086         if (!(journal = ext4_get_journal(sb, journal_inum)))
2087                 return -EINVAL;
2088
2089         printk(KERN_INFO "EXT4-fs: creating new journal on inode %u\n",
2090                journal_inum);
2091
2092         if (jbd2_journal_create(journal)) {
2093                 printk(KERN_ERR "EXT4-fs: error creating journal.\n");
2094                 jbd2_journal_destroy(journal);
2095                 return -EIO;
2096         }
2097
2098         EXT4_SB(sb)->s_journal = journal;
2099
2100         ext4_update_dynamic_rev(sb);
2101         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2102         EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL);
2103
2104         es->s_journal_inum = cpu_to_le32(journal_inum);
2105         sb->s_dirt = 1;
2106
2107         /* Make sure we flush the recovery flag to disk. */
2108         ext4_commit_super(sb, es, 1);
2109
2110         return 0;
2111 }
2112
2113 static void ext4_commit_super (struct super_block * sb,
2114                                struct ext4_super_block * es,
2115                                int sync)
2116 {
2117         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
2118
2119         if (!sbh)
2120                 return;
2121         es->s_wtime = cpu_to_le32(get_seconds());
2122         es->s_free_blocks_count = cpu_to_le32(ext4_count_free_blocks(sb));
2123         es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
2124         BUFFER_TRACE(sbh, "marking dirty");
2125         mark_buffer_dirty(sbh);
2126         if (sync)
2127                 sync_dirty_buffer(sbh);
2128 }
2129
2130
2131 /*
2132  * Have we just finished recovery?  If so, and if we are mounting (or
2133  * remounting) the filesystem readonly, then we will end up with a
2134  * consistent fs on disk.  Record that fact.
2135  */
2136 static void ext4_mark_recovery_complete(struct super_block * sb,
2137                                         struct ext4_super_block * es)
2138 {
2139         journal_t *journal = EXT4_SB(sb)->s_journal;
2140
2141         jbd2_journal_lock_updates(journal);
2142         jbd2_journal_flush(journal);
2143         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
2144             sb->s_flags & MS_RDONLY) {
2145                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2146                 sb->s_dirt = 0;
2147                 ext4_commit_super(sb, es, 1);
2148         }
2149         jbd2_journal_unlock_updates(journal);
2150 }
2151
2152 /*
2153  * If we are mounting (or read-write remounting) a filesystem whose journal
2154  * has recorded an error from a previous lifetime, move that error to the
2155  * main filesystem now.
2156  */
2157 static void ext4_clear_journal_err(struct super_block * sb,
2158                                    struct ext4_super_block * es)
2159 {
2160         journal_t *journal;
2161         int j_errno;
2162         const char *errstr;
2163
2164         journal = EXT4_SB(sb)->s_journal;
2165
2166         /*
2167          * Now check for any error status which may have been recorded in the
2168          * journal by a prior ext4_error() or ext4_abort()
2169          */
2170
2171         j_errno = jbd2_journal_errno(journal);
2172         if (j_errno) {
2173                 char nbuf[16];
2174
2175                 errstr = ext4_decode_error(sb, j_errno, nbuf);
2176                 ext4_warning(sb, __FUNCTION__, "Filesystem error recorded "
2177                              "from previous mount: %s", errstr);
2178                 ext4_warning(sb, __FUNCTION__, "Marking fs in need of "
2179                              "filesystem check.");
2180
2181                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2182                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2183                 ext4_commit_super (sb, es, 1);
2184
2185                 jbd2_journal_clear_err(journal);
2186         }
2187 }
2188
2189 /*
2190  * Force the running and committing transactions to commit,
2191  * and wait on the commit.
2192  */
2193 int ext4_force_commit(struct super_block *sb)
2194 {
2195         journal_t *journal;
2196         int ret;
2197
2198         if (sb->s_flags & MS_RDONLY)
2199                 return 0;
2200
2201         journal = EXT4_SB(sb)->s_journal;
2202         sb->s_dirt = 0;
2203         ret = ext4_journal_force_commit(journal);
2204         return ret;
2205 }
2206
2207 /*
2208  * Ext4 always journals updates to the superblock itself, so we don't
2209  * have to propagate any other updates to the superblock on disk at this
2210  * point.  Just start an async writeback to get the buffers on their way
2211  * to the disk.
2212  *
2213  * This implicitly triggers the writebehind on sync().
2214  */
2215
2216 static void ext4_write_super (struct super_block * sb)
2217 {
2218         if (mutex_trylock(&sb->s_lock) != 0)
2219                 BUG();
2220         sb->s_dirt = 0;
2221 }
2222
2223 static int ext4_sync_fs(struct super_block *sb, int wait)
2224 {
2225         tid_t target;
2226
2227         sb->s_dirt = 0;
2228         if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, &target)) {
2229                 if (wait)
2230                         jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, target);
2231         }
2232         return 0;
2233 }
2234
2235 /*
2236  * LVM calls this function before a (read-only) snapshot is created.  This
2237  * gives us a chance to flush the journal completely and mark the fs clean.
2238  */
2239 static void ext4_write_super_lockfs(struct super_block *sb)
2240 {
2241         sb->s_dirt = 0;
2242
2243         if (!(sb->s_flags & MS_RDONLY)) {
2244                 journal_t *journal = EXT4_SB(sb)->s_journal;
2245
2246                 /* Now we set up the journal barrier. */
2247                 jbd2_journal_lock_updates(journal);
2248                 jbd2_journal_flush(journal);
2249
2250                 /* Journal blocked and flushed, clear needs_recovery flag. */
2251                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2252                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2253         }
2254 }
2255
2256 /*
2257  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
2258  * flag here, even though the filesystem is not technically dirty yet.
2259  */
2260 static void ext4_unlockfs(struct super_block *sb)
2261 {
2262         if (!(sb->s_flags & MS_RDONLY)) {
2263                 lock_super(sb);
2264                 /* Reser the needs_recovery flag before the fs is unlocked. */
2265                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2266                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2267                 unlock_super(sb);
2268                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
2269         }
2270 }
2271
2272 static int ext4_remount (struct super_block * sb, int * flags, char * data)
2273 {
2274         struct ext4_super_block * es;
2275         struct ext4_sb_info *sbi = EXT4_SB(sb);
2276         ext4_fsblk_t n_blocks_count = 0;
2277         unsigned long old_sb_flags;
2278         struct ext4_mount_options old_opts;
2279         int err;
2280 #ifdef CONFIG_QUOTA
2281         int i;
2282 #endif
2283
2284         /* Store the original options */
2285         old_sb_flags = sb->s_flags;
2286         old_opts.s_mount_opt = sbi->s_mount_opt;
2287         old_opts.s_resuid = sbi->s_resuid;
2288         old_opts.s_resgid = sbi->s_resgid;
2289         old_opts.s_commit_interval = sbi->s_commit_interval;
2290 #ifdef CONFIG_QUOTA
2291         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
2292         for (i = 0; i < MAXQUOTAS; i++)
2293                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
2294 #endif
2295
2296         /*
2297          * Allow the "check" option to be passed as a remount option.
2298          */
2299         if (!parse_options(data, sb, NULL, NULL, &n_blocks_count, 1)) {
2300                 err = -EINVAL;
2301                 goto restore_opts;
2302         }
2303
2304         if (sbi->s_mount_opt & EXT4_MOUNT_ABORT)
2305                 ext4_abort(sb, __FUNCTION__, "Abort forced by user");
2306
2307         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2308                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2309
2310         es = sbi->s_es;
2311
2312         ext4_init_journal_params(sb, sbi->s_journal);
2313
2314         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
2315                 n_blocks_count > le32_to_cpu(es->s_blocks_count)) {
2316                 if (sbi->s_mount_opt & EXT4_MOUNT_ABORT) {
2317                         err = -EROFS;
2318                         goto restore_opts;
2319                 }
2320
2321                 if (*flags & MS_RDONLY) {
2322                         /*
2323                          * First of all, the unconditional stuff we have to do
2324                          * to disable replay of the journal when we next remount
2325                          */
2326                         sb->s_flags |= MS_RDONLY;
2327
2328                         /*
2329                          * OK, test if we are remounting a valid rw partition
2330                          * readonly, and if so set the rdonly flag and then
2331                          * mark the partition as valid again.
2332                          */
2333                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
2334                             (sbi->s_mount_state & EXT4_VALID_FS))
2335                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
2336
2337                         ext4_mark_recovery_complete(sb, es);
2338                 } else {
2339                         __le32 ret;
2340                         if ((ret = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2341                                         ~EXT4_FEATURE_RO_COMPAT_SUPP))) {
2342                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
2343                                        "remount RDWR because of unsupported "
2344                                        "optional features (%x).\n",
2345                                        sb->s_id, le32_to_cpu(ret));
2346                                 err = -EROFS;
2347                                 goto restore_opts;
2348                         }
2349                         /*
2350                          * Mounting a RDONLY partition read-write, so reread
2351                          * and store the current valid flag.  (It may have
2352                          * been changed by e2fsck since we originally mounted
2353                          * the partition.)
2354                          */
2355                         ext4_clear_journal_err(sb, es);
2356                         sbi->s_mount_state = le16_to_cpu(es->s_state);
2357                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
2358                                 goto restore_opts;
2359                         if (!ext4_setup_super (sb, es, 0))
2360                                 sb->s_flags &= ~MS_RDONLY;
2361                 }
2362         }
2363 #ifdef CONFIG_QUOTA
2364         /* Release old quota file names */
2365         for (i = 0; i < MAXQUOTAS; i++)
2366                 if (old_opts.s_qf_names[i] &&
2367                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
2368                         kfree(old_opts.s_qf_names[i]);
2369 #endif
2370         return 0;
2371 restore_opts:
2372         sb->s_flags = old_sb_flags;
2373         sbi->s_mount_opt = old_opts.s_mount_opt;
2374         sbi->s_resuid = old_opts.s_resuid;
2375         sbi->s_resgid = old_opts.s_resgid;
2376         sbi->s_commit_interval = old_opts.s_commit_interval;
2377 #ifdef CONFIG_QUOTA
2378         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
2379         for (i = 0; i < MAXQUOTAS; i++) {
2380                 if (sbi->s_qf_names[i] &&
2381                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
2382                         kfree(sbi->s_qf_names[i]);
2383                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
2384         }
2385 #endif
2386         return err;
2387 }
2388
2389 static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf)
2390 {
2391         struct super_block *sb = dentry->d_sb;
2392         struct ext4_sb_info *sbi = EXT4_SB(sb);
2393         struct ext4_super_block *es = sbi->s_es;
2394         ext4_fsblk_t overhead;
2395         int i;
2396
2397         if (test_opt (sb, MINIX_DF))
2398                 overhead = 0;
2399         else {
2400                 unsigned long ngroups;
2401                 ngroups = EXT4_SB(sb)->s_groups_count;
2402                 smp_rmb();
2403
2404                 /*
2405                  * Compute the overhead (FS structures)
2406                  */
2407
2408                 /*
2409                  * All of the blocks before first_data_block are
2410                  * overhead
2411                  */
2412                 overhead = le32_to_cpu(es->s_first_data_block);
2413
2414                 /*
2415                  * Add the overhead attributed to the superblock and
2416                  * block group descriptors.  If the sparse superblocks
2417                  * feature is turned on, then not all groups have this.
2418                  */
2419                 for (i = 0; i < ngroups; i++) {
2420                         overhead += ext4_bg_has_super(sb, i) +
2421                                 ext4_bg_num_gdb(sb, i);
2422                         cond_resched();
2423                 }
2424
2425                 /*
2426                  * Every block group has an inode bitmap, a block
2427                  * bitmap, and an inode table.
2428                  */
2429                 overhead += (ngroups * (2 + EXT4_SB(sb)->s_itb_per_group));
2430         }
2431
2432         buf->f_type = EXT4_SUPER_MAGIC;
2433         buf->f_bsize = sb->s_blocksize;
2434         buf->f_blocks = le32_to_cpu(es->s_blocks_count) - overhead;
2435         buf->f_bfree = percpu_counter_sum(&sbi->s_freeblocks_counter);
2436         buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
2437         if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
2438                 buf->f_bavail = 0;
2439         buf->f_files = le32_to_cpu(es->s_inodes_count);
2440         buf->f_ffree = percpu_counter_sum(&sbi->s_freeinodes_counter);
2441         buf->f_namelen = EXT4_NAME_LEN;
2442         return 0;
2443 }
2444
2445 /* Helper function for writing quotas on sync - we need to start transaction before quota file
2446  * is locked for write. Otherwise the are possible deadlocks:
2447  * Process 1                         Process 2
2448  * ext4_create()                     quota_sync()
2449  *   jbd2_journal_start()                   write_dquot()
2450  *   DQUOT_INIT()                        down(dqio_mutex)
2451  *     down(dqio_mutex)                    jbd2_journal_start()
2452  *
2453  */
2454
2455 #ifdef CONFIG_QUOTA
2456
2457 static inline struct inode *dquot_to_inode(struct dquot *dquot)
2458 {
2459         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
2460 }
2461
2462 static int ext4_dquot_initialize(struct inode *inode, int type)
2463 {
2464         handle_t *handle;
2465         int ret, err;
2466
2467         /* We may create quota structure so we need to reserve enough blocks */
2468         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_INIT_BLOCKS(inode->i_sb));
2469         if (IS_ERR(handle))
2470                 return PTR_ERR(handle);
2471         ret = dquot_initialize(inode, type);
2472         err = ext4_journal_stop(handle);
2473         if (!ret)
2474                 ret = err;
2475         return ret;
2476 }
2477
2478 static int ext4_dquot_drop(struct inode *inode)
2479 {
2480         handle_t *handle;
2481         int ret, err;
2482
2483         /* We may delete quota structure so we need to reserve enough blocks */
2484         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_DEL_BLOCKS(inode->i_sb));
2485         if (IS_ERR(handle))
2486                 return PTR_ERR(handle);
2487         ret = dquot_drop(inode);
2488         err = ext4_journal_stop(handle);
2489         if (!ret)
2490                 ret = err;
2491         return ret;
2492 }
2493
2494 static int ext4_write_dquot(struct dquot *dquot)
2495 {
2496         int ret, err;
2497         handle_t *handle;
2498         struct inode *inode;
2499
2500         inode = dquot_to_inode(dquot);
2501         handle = ext4_journal_start(inode,
2502                                         EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
2503         if (IS_ERR(handle))
2504                 return PTR_ERR(handle);
2505         ret = dquot_commit(dquot);
2506         err = ext4_journal_stop(handle);
2507         if (!ret)
2508                 ret = err;
2509         return ret;
2510 }
2511
2512 static int ext4_acquire_dquot(struct dquot *dquot)
2513 {
2514         int ret, err;
2515         handle_t *handle;
2516
2517         handle = ext4_journal_start(dquot_to_inode(dquot),
2518                                         EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
2519         if (IS_ERR(handle))
2520                 return PTR_ERR(handle);
2521         ret = dquot_acquire(dquot);
2522         err = ext4_journal_stop(handle);
2523         if (!ret)
2524                 ret = err;
2525         return ret;
2526 }
2527
2528 static int ext4_release_dquot(struct dquot *dquot)
2529 {
2530         int ret, err;
2531         handle_t *handle;
2532
2533         handle = ext4_journal_start(dquot_to_inode(dquot),
2534                                         EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
2535         if (IS_ERR(handle))
2536                 return PTR_ERR(handle);
2537         ret = dquot_release(dquot);
2538         err = ext4_journal_stop(handle);
2539         if (!ret)
2540                 ret = err;
2541         return ret;
2542 }
2543
2544 static int ext4_mark_dquot_dirty(struct dquot *dquot)
2545 {
2546         /* Are we journalling quotas? */
2547         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
2548             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
2549                 dquot_mark_dquot_dirty(dquot);
2550                 return ext4_write_dquot(dquot);
2551         } else {
2552                 return dquot_mark_dquot_dirty(dquot);
2553         }
2554 }
2555
2556 static int ext4_write_info(struct super_block *sb, int type)
2557 {
2558         int ret, err;
2559         handle_t *handle;
2560
2561         /* Data block + inode block */
2562         handle = ext4_journal_start(sb->s_root->d_inode, 2);
2563         if (IS_ERR(handle))
2564                 return PTR_ERR(handle);
2565         ret = dquot_commit_info(sb, type);
2566         err = ext4_journal_stop(handle);
2567         if (!ret)
2568                 ret = err;
2569         return ret;
2570 }
2571
2572 /*
2573  * Turn on quotas during mount time - we need to find
2574  * the quota file and such...
2575  */
2576 static int ext4_quota_on_mount(struct super_block *sb, int type)
2577 {
2578         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
2579                         EXT4_SB(sb)->s_jquota_fmt, type);
2580 }
2581
2582 /*
2583  * Standard function to be called on quota_on
2584  */
2585 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
2586                          char *path)
2587 {
2588         int err;
2589         struct nameidata nd;
2590
2591         if (!test_opt(sb, QUOTA))
2592                 return -EINVAL;
2593         /* Not journalling quota? */
2594         if (!EXT4_SB(sb)->s_qf_names[USRQUOTA] &&
2595             !EXT4_SB(sb)->s_qf_names[GRPQUOTA])
2596                 return vfs_quota_on(sb, type, format_id, path);
2597         err = path_lookup(path, LOOKUP_FOLLOW, &nd);
2598         if (err)
2599                 return err;
2600         /* Quotafile not on the same filesystem? */
2601         if (nd.mnt->mnt_sb != sb) {
2602                 path_release(&nd);
2603                 return -EXDEV;
2604         }
2605         /* Quotafile not of fs root? */
2606         if (nd.dentry->d_parent->d_inode != sb->s_root->d_inode)
2607                 printk(KERN_WARNING
2608                         "EXT4-fs: Quota file not on filesystem root. "
2609                         "Journalled quota will not work.\n");
2610         path_release(&nd);
2611         return vfs_quota_on(sb, type, format_id, path);
2612 }
2613
2614 /* Read data from quotafile - avoid pagecache and such because we cannot afford
2615  * acquiring the locks... As quota files are never truncated and quota code
2616  * itself serializes the operations (and noone else should touch the files)
2617  * we don't have to be afraid of races */
2618 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
2619                                size_t len, loff_t off)
2620 {
2621         struct inode *inode = sb_dqopt(sb)->files[type];
2622         sector_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
2623         int err = 0;
2624         int offset = off & (sb->s_blocksize - 1);
2625         int tocopy;
2626         size_t toread;
2627         struct buffer_head *bh;
2628         loff_t i_size = i_size_read(inode);
2629
2630         if (off > i_size)
2631                 return 0;
2632         if (off+len > i_size)
2633                 len = i_size-off;
2634         toread = len;
2635         while (toread > 0) {
2636                 tocopy = sb->s_blocksize - offset < toread ?
2637                                 sb->s_blocksize - offset : toread;
2638                 bh = ext4_bread(NULL, inode, blk, 0, &err);
2639                 if (err)
2640                         return err;
2641                 if (!bh)        /* A hole? */
2642                         memset(data, 0, tocopy);
2643                 else
2644                         memcpy(data, bh->b_data+offset, tocopy);
2645                 brelse(bh);
2646                 offset = 0;
2647                 toread -= tocopy;
2648                 data += tocopy;
2649                 blk++;
2650         }
2651         return len;
2652 }
2653
2654 /* Write to quotafile (we know the transaction is already started and has
2655  * enough credits) */
2656 static ssize_t ext4_quota_write(struct super_block *sb, int type,
2657                                 const char *data, size_t len, loff_t off)
2658 {
2659         struct inode *inode = sb_dqopt(sb)->files[type];
2660         sector_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
2661         int err = 0;
2662         int offset = off & (sb->s_blocksize - 1);
2663         int tocopy;
2664         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
2665         size_t towrite = len;
2666         struct buffer_head *bh;
2667         handle_t *handle = journal_current_handle();
2668
2669         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
2670         while (towrite > 0) {
2671                 tocopy = sb->s_blocksize - offset < towrite ?
2672                                 sb->s_blocksize - offset : towrite;
2673                 bh = ext4_bread(handle, inode, blk, 1, &err);
2674                 if (!bh)
2675                         goto out;
2676                 if (journal_quota) {
2677                         err = ext4_journal_get_write_access(handle, bh);
2678                         if (err) {
2679                                 brelse(bh);
2680                                 goto out;
2681                         }
2682                 }
2683                 lock_buffer(bh);
2684                 memcpy(bh->b_data+offset, data, tocopy);
2685                 flush_dcache_page(bh->b_page);
2686                 unlock_buffer(bh);
2687                 if (journal_quota)
2688                         err = ext4_journal_dirty_metadata(handle, bh);
2689                 else {
2690                         /* Always do at least ordered writes for quotas */
2691                         err = ext4_journal_dirty_data(handle, bh);
2692                         mark_buffer_dirty(bh);
2693                 }
2694                 brelse(bh);
2695                 if (err)
2696                         goto out;
2697                 offset = 0;
2698                 towrite -= tocopy;
2699                 data += tocopy;
2700                 blk++;
2701         }
2702 out:
2703         if (len == towrite)
2704                 return err;
2705         if (inode->i_size < off+len-towrite) {
2706                 i_size_write(inode, off+len-towrite);
2707                 EXT4_I(inode)->i_disksize = inode->i_size;
2708         }
2709         inode->i_version++;
2710         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2711         ext4_mark_inode_dirty(handle, inode);
2712         mutex_unlock(&inode->i_mutex);
2713         return len - towrite;
2714 }
2715
2716 #endif
2717
2718 static int ext4_get_sb(struct file_system_type *fs_type,
2719         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
2720 {
2721         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
2722 }
2723
2724 static struct file_system_type ext4dev_fs_type = {
2725         .owner          = THIS_MODULE,
2726         .name           = "ext4dev",
2727         .get_sb         = ext4_get_sb,
2728         .kill_sb        = kill_block_super,
2729         .fs_flags       = FS_REQUIRES_DEV,
2730 };
2731
2732 static int __init init_ext4_fs(void)
2733 {
2734         int err = init_ext4_xattr();
2735         if (err)
2736                 return err;
2737         err = init_inodecache();
2738         if (err)
2739                 goto out1;
2740         err = register_filesystem(&ext4dev_fs_type);
2741         if (err)
2742                 goto out;
2743         return 0;
2744 out:
2745         destroy_inodecache();
2746 out1:
2747         exit_ext4_xattr();
2748         return err;
2749 }
2750
2751 static void __exit exit_ext4_fs(void)
2752 {
2753         unregister_filesystem(&ext4dev_fs_type);
2754         destroy_inodecache();
2755         exit_ext4_xattr();
2756 }
2757
2758 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
2759 MODULE_DESCRIPTION("Fourth Extended Filesystem with extents");
2760 MODULE_LICENSE("GPL");
2761 module_init(init_ext4_fs)
2762 module_exit(exit_ext4_fs)