fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/jbd2.h>
  24 #include <linux/slab.h>
  25 #include <linux/init.h>
  26 #include <linux/blkdev.h>
  27 #include <linux/parser.h>
  28 #include <linux/smp_lock.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/log2.h>
  38 #include <linux/crc16.h>
  39 #include <asm/uaccess.h>
  40
  41 #include "ext4.h"
  42 #include "ext4_jbd2.h"
  43 #include "xattr.h"
  44 #include "acl.h"
  45 #include "namei.h"
  46 #include "group.h"
  47
  48 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  49                              unsigned long journal_devnum);
  50 static int ext4_create_journal(struct super_block *, struct ext4_super_block *,
  51                                unsigned int);
  52 static void ext4_commit_super(struct super_block *sb,
  53                               struct ext4_super_block *es, int sync);
  54 static void ext4_mark_recovery_complete(struct super_block *sb,
  55                                         struct ext4_super_block *es);
  56 static void ext4_clear_journal_err(struct super_block *sb,
  57                                    struct ext4_super_block *es);
  58 static int ext4_sync_fs(struct super_block *sb, int wait);
  59 static const char *ext4_decode_error(struct super_block *sb, int errno,
  60                                      char nbuf[16]);
  61 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  62 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  63 static void ext4_unlockfs(struct super_block *sb);
  64 static void ext4_write_super(struct super_block *sb);
  65 static void ext4_write_super_lockfs(struct super_block *sb);
  66
  67
  68 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
  69                                struct ext4_group_desc *bg)
  70 {
  71         return le32_to_cpu(bg->bg_block_bitmap_lo) |
  72                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  73                 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
  74 }
  75
  76 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
  77                                struct ext4_group_desc *bg)
  78 {
  79         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
  80                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  81                 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
  82 }
  83
  84 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
  85                               struct ext4_group_desc *bg)
  86 {
  87         return le32_to_cpu(bg->bg_inode_table_lo) |
  88                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  89                 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
  90 }
  91
  92 void ext4_block_bitmap_set(struct super_block *sb,
  93                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
  94 {
  95         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
  96         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
  97                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
  98 }
  99
 100 void ext4_inode_bitmap_set(struct super_block *sb,
 101                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 102 {
 103         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 104         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 105                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 106 }
 107
 108 void ext4_inode_table_set(struct super_block *sb,
 109                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 110 {
 111         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 112         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 113                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 114 }
 115
 116 /*
 117  * Wrappers for jbd2_journal_start/end.
 118  *
 119  * The only special thing we need to do here is to make sure that all
 120  * journal_end calls result in the superblock being marked dirty, so
 121  * that sync() will call the filesystem's write_super callback if
 122  * appropriate.
 123  */
 124 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 125 {
 126         journal_t *journal;
 127
 128         if (sb->s_flags & MS_RDONLY)
 129                 return ERR_PTR(-EROFS);
 130
 131         /* Special case here: if the journal has aborted behind our
 132          * backs (eg. EIO in the commit thread), then we still need to
 133          * take the FS itself readonly cleanly. */
 134         journal = EXT4_SB(sb)->s_journal;
 135         if (is_journal_aborted(journal)) {
 136                 ext4_abort(sb, __func__,
 137                            "Detected aborted journal");
 138                 return ERR_PTR(-EROFS);
 139         }
 140
 141         return jbd2_journal_start(journal, nblocks);
 142 }
 143
 144 /*
 145  * The only special thing we need to do here is to make sure that all
 146  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 147  * that sync() will call the filesystem's write_super callback if
 148  * appropriate.
 149  */
 150 int __ext4_journal_stop(const char *where, handle_t *handle)
 151 {
 152         struct super_block *sb;
 153         int err;
 154         int rc;
 155
 156         sb = handle->h_transaction->t_journal->j_private;
 157         err = handle->h_err;
 158         rc = jbd2_journal_stop(handle);
 159
 160         if (!err)
 161                 err = rc;
 162         if (err)
 163                 __ext4_std_error(sb, where, err);
 164         return err;
 165 }
 166
 167 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 168                 struct buffer_head *bh, handle_t *handle, int err)
 169 {
 170         char nbuf[16];
 171         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 172
 173         if (bh)
 174                 BUFFER_TRACE(bh, "abort");
 175
 176         if (!handle->h_err)
 177                 handle->h_err = err;
 178
 179         if (is_handle_aborted(handle))
 180                 return;
 181
 182         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
 183                caller, errstr, err_fn);
 184
 185         jbd2_journal_abort_handle(handle);
 186 }
 187
 188 /* Deal with the reporting of failure conditions on a filesystem such as
 189  * inconsistencies detected or read IO failures.
 190  *
 191  * On ext2, we can store the error state of the filesystem in the
 192  * superblock.  That is not possible on ext4, because we may have other
 193  * write ordering constraints on the superblock which prevent us from
 194  * writing it out straight away; and given that the journal is about to
 195  * be aborted, we can't rely on the current, or future, transactions to
 196  * write out the superblock safely.
 197  *
 198  * We'll just use the jbd2_journal_abort() error code to record an error in
 199  * the journal instead.  On recovery, the journal will compain about
 200  * that error until we've noted it down and cleared it.
 201  */
 202
 203 static void ext4_handle_error(struct super_block *sb)
 204 {
 205         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 206
 207         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 208         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 209
 210         if (sb->s_flags & MS_RDONLY)
 211                 return;
 212
 213         if (!test_opt(sb, ERRORS_CONT)) {
 214                 journal_t *journal = EXT4_SB(sb)->s_journal;
 215
 216                 EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 217                 if (journal)
 218                         jbd2_journal_abort(journal, -EIO);
 219         }
 220         if (test_opt(sb, ERRORS_RO)) {
 221                 printk(KERN_CRIT "Remounting filesystem read-only\n");
 222                 sb->s_flags |= MS_RDONLY;
 223         }
 224         ext4_commit_super(sb, es, 1);
 225         if (test_opt(sb, ERRORS_PANIC))
 226                 panic("EXT4-fs (device %s): panic forced after error\n",
 227                         sb->s_id);
 228 }
 229
 230 void ext4_error(struct super_block *sb, const char *function,
 231                 const char *fmt, ...)
 232 {
 233         va_list args;
 234
 235         va_start(args, fmt);
 236         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 237         vprintk(fmt, args);
 238         printk("\n");
 239         va_end(args);
 240
 241         ext4_handle_error(sb);
 242 }
 243
 244 static const char *ext4_decode_error(struct super_block *sb, int errno,
 245                                      char nbuf[16])
 246 {
 247         char *errstr = NULL;
 248
 249         switch (errno) {
 250         case -EIO:
 251                 errstr = "IO failure";
 252                 break;
 253         case -ENOMEM:
 254                 errstr = "Out of memory";
 255                 break;
 256         case -EROFS:
 257                 if (!sb || EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT)
 258                         errstr = "Journal has aborted";
 259                 else
 260                         errstr = "Readonly filesystem";
 261                 break;
 262         default:
 263                 /* If the caller passed in an extra buffer for unknown
 264                  * errors, textualise them now.  Else we just return
 265                  * NULL. */
 266                 if (nbuf) {
 267                         /* Check for truncated error codes... */
 268                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 269                                 errstr = nbuf;
 270                 }
 271                 break;
 272         }
 273
 274         return errstr;
 275 }
 276
 277 /* __ext4_std_error decodes expected errors from journaling functions
 278  * automatically and invokes the appropriate error response.  */
 279
 280 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
 281 {
 282         char nbuf[16];
 283         const char *errstr;
 284
 285         /* Special case: if the error is EROFS, and we're not already
 286          * inside a transaction, then there's really no point in logging
 287          * an error. */
 288         if (errno == -EROFS && journal_current_handle() == NULL &&
 289             (sb->s_flags & MS_RDONLY))
 290                 return;
 291
 292         errstr = ext4_decode_error(sb, errno, nbuf);
 293         printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
 294                sb->s_id, function, errstr);
 295
 296         ext4_handle_error(sb);
 297 }
 298
 299 /*
 300  * ext4_abort is a much stronger failure handler than ext4_error.  The
 301  * abort function may be used to deal with unrecoverable failures such
 302  * as journal IO errors or ENOMEM at a critical moment in log management.
 303  *
 304  * We unconditionally force the filesystem into an ABORT|READONLY state,
 305  * unless the error response on the fs has been set to panic in which
 306  * case we take the easy way out and panic immediately.
 307  */
 308
 309 void ext4_abort(struct super_block *sb, const char *function,
 310                 const char *fmt, ...)
 311 {
 312         va_list args;
 313
 314         printk(KERN_CRIT "ext4_abort called.\n");
 315
 316         va_start(args, fmt);
 317         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
 318         vprintk(fmt, args);
 319         printk("\n");
 320         va_end(args);
 321
 322         if (test_opt(sb, ERRORS_PANIC))
 323                 panic("EXT4-fs panic from previous error\n");
 324
 325         if (sb->s_flags & MS_RDONLY)
 326                 return;
 327
 328         printk(KERN_CRIT "Remounting filesystem read-only\n");
 329         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 330         sb->s_flags |= MS_RDONLY;
 331         EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
 332         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 333 }
 334
 335 void ext4_warning(struct super_block *sb, const char *function,
 336                   const char *fmt, ...)
 337 {
 338         va_list args;
 339
 340         va_start(args, fmt);
 341         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
 342                sb->s_id, function);
 343         vprintk(fmt, args);
 344         printk("\n");
 345         va_end(args);
 346 }
 347
 348 void ext4_update_dynamic_rev(struct super_block *sb)
 349 {
 350         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 351
 352         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 353                 return;
 354
 355         ext4_warning(sb, __func__,
 356                      "updating to rev %d because of new feature flag, "
 357                      "running e2fsck is recommended",
 358                      EXT4_DYNAMIC_REV);
 359
 360         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 361         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 362         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 363         /* leave es->s_feature_*compat flags alone */
 364         /* es->s_uuid will be set by e2fsck if empty */
 365
 366         /*
 367          * The rest of the superblock fields should be zero, and if not it
 368          * means they are likely already in use, so leave them alone.  We
 369          * can leave it up to e2fsck to clean up any inconsistencies there.
 370          */
 371 }
 372
 373 int ext4_update_compat_feature(handle_t *handle,
 374                                         struct super_block *sb, __u32 compat)
 375 {
 376         int err = 0;
 377         if (!EXT4_HAS_COMPAT_FEATURE(sb, compat)) {
 378                 err = ext4_journal_get_write_access(handle,
 379                                 EXT4_SB(sb)->s_sbh);
 380                 if (err)
 381                         return err;
 382                 EXT4_SET_COMPAT_FEATURE(sb, compat);
 383                 sb->s_dirt = 1;
 384                 handle->h_sync = 1;
 385                 BUFFER_TRACE(EXT4_SB(sb)->s_sbh,
 386                                         "call ext4_journal_dirty_met adata");
 387                 err = ext4_journal_dirty_metadata(handle,
 388                                 EXT4_SB(sb)->s_sbh);
 389         }
 390         return err;
 391 }
 392
 393 int ext4_update_rocompat_feature(handle_t *handle,
 394                                         struct super_block *sb, __u32 rocompat)
 395 {
 396         int err = 0;
 397         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, rocompat)) {
 398                 err = ext4_journal_get_write_access(handle,
 399                                 EXT4_SB(sb)->s_sbh);
 400                 if (err)
 401                         return err;
 402                 EXT4_SET_RO_COMPAT_FEATURE(sb, rocompat);
 403                 sb->s_dirt = 1;
 404                 handle->h_sync = 1;
 405                 BUFFER_TRACE(EXT4_SB(sb)->s_sbh,
 406                                         "call ext4_journal_dirty_met adata");
 407                 err = ext4_journal_dirty_metadata(handle,
 408                                 EXT4_SB(sb)->s_sbh);
 409         }
 410         return err;
 411 }
 412
 413 int ext4_update_incompat_feature(handle_t *handle,
 414                                         struct super_block *sb, __u32 incompat)
 415 {
 416         int err = 0;
 417         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, incompat)) {
 418                 err = ext4_journal_get_write_access(handle,
 419                                 EXT4_SB(sb)->s_sbh);
 420                 if (err)
 421                         return err;
 422                 EXT4_SET_INCOMPAT_FEATURE(sb, incompat);
 423                 sb->s_dirt = 1;
 424                 handle->h_sync = 1;
 425                 BUFFER_TRACE(EXT4_SB(sb)->s_sbh,
 426                                         "call ext4_journal_dirty_met adata");
 427                 err = ext4_journal_dirty_metadata(handle,
 428                                 EXT4_SB(sb)->s_sbh);
 429         }
 430         return err;
 431 }
 432
 433 /*
 434  * Open the external journal device
 435  */
 436 static struct block_device *ext4_blkdev_get(dev_t dev)
 437 {
 438         struct block_device *bdev;
 439         char b[BDEVNAME_SIZE];
 440
 441         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 442         if (IS_ERR(bdev))
 443                 goto fail;
 444         return bdev;
 445
 446 fail:
 447         printk(KERN_ERR "EXT4: failed to open journal device %s: %ld\n",
 448                         __bdevname(dev, b), PTR_ERR(bdev));
 449         return NULL;
 450 }
 451
 452 /*
 453  * Release the journal device
 454  */
 455 static int ext4_blkdev_put(struct block_device *bdev)
 456 {
 457         bd_release(bdev);
 458         return blkdev_put(bdev);
 459 }
 460
 461 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 462 {
 463         struct block_device *bdev;
 464         int ret = -ENODEV;
 465
 466         bdev = sbi->journal_bdev;
 467         if (bdev) {
 468                 ret = ext4_blkdev_put(bdev);
 469                 sbi->journal_bdev = NULL;
 470         }
 471         return ret;
 472 }
 473
 474 static inline struct inode *orphan_list_entry(struct list_head *l)
 475 {
 476         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 477 }
 478
 479 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 480 {
 481         struct list_head *l;
 482
 483         printk(KERN_ERR "sb orphan head is %d\n",
 484                le32_to_cpu(sbi->s_es->s_last_orphan));
 485
 486         printk(KERN_ERR "sb_info orphan list:\n");
 487         list_for_each(l, &sbi->s_orphan) {
 488                 struct inode *inode = orphan_list_entry(l);
 489                 printk(KERN_ERR "  "
 490                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 491                        inode->i_sb->s_id, inode->i_ino, inode,
 492                        inode->i_mode, inode->i_nlink,
 493                        NEXT_ORPHAN(inode));
 494         }
 495 }
 496
 497 static void ext4_put_super(struct super_block *sb)
 498 {
 499         struct ext4_sb_info *sbi = EXT4_SB(sb);
 500         struct ext4_super_block *es = sbi->s_es;
 501         int i;
 502
 503         ext4_mb_release(sb);
 504         ext4_ext_release(sb);
 505         ext4_xattr_put_super(sb);
 506         jbd2_journal_destroy(sbi->s_journal);
 507         sbi->s_journal = NULL;
 508         if (!(sb->s_flags & MS_RDONLY)) {
 509                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 510                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 511                 BUFFER_TRACE(sbi->s_sbh, "marking dirty");
 512                 mark_buffer_dirty(sbi->s_sbh);
 513                 ext4_commit_super(sb, es, 1);
 514         }
 515
 516         for (i = 0; i < sbi->s_gdb_count; i++)
 517                 brelse(sbi->s_group_desc[i]);
 518         kfree(sbi->s_group_desc);
 519         kfree(sbi->s_flex_groups);
 520         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 521         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 522         percpu_counter_destroy(&sbi->s_dirs_counter);
 523         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
 524         brelse(sbi->s_sbh);
 525 #ifdef CONFIG_QUOTA
 526         for (i = 0; i < MAXQUOTAS; i++)
 527                 kfree(sbi->s_qf_names[i]);
 528 #endif
 529
 530         /* Debugging code just in case the in-memory inode orphan list
 531          * isn't empty.  The on-disk one can be non-empty if we've
 532          * detected an error and taken the fs readonly, but the
 533          * in-memory list had better be clean by this point. */
 534         if (!list_empty(&sbi->s_orphan))
 535                 dump_orphan_list(sb, sbi);
 536         J_ASSERT(list_empty(&sbi->s_orphan));
 537
 538         invalidate_bdev(sb->s_bdev);
 539         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 540                 /*
 541                  * Invalidate the journal device's buffers.  We don't want them
 542                  * floating about in memory - the physical journal device may
 543                  * hotswapped, and it breaks the `ro-after' testing code.
 544                  */
 545                 sync_blockdev(sbi->journal_bdev);
 546                 invalidate_bdev(sbi->journal_bdev);
 547                 ext4_blkdev_remove(sbi);
 548         }
 549         sb->s_fs_info = NULL;
 550         kfree(sbi);
 551         return;
 552 }
 553
 554 static struct kmem_cache *ext4_inode_cachep;
 555
 556 /*
 557  * Called inside transaction, so use GFP_NOFS
 558  */
 559 static struct inode *ext4_alloc_inode(struct super_block *sb)
 560 {
 561         struct ext4_inode_info *ei;
 562
 563         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 564         if (!ei)
 565                 return NULL;
 566 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 567         ei->i_acl = EXT4_ACL_NOT_CACHED;
 568         ei->i_default_acl = EXT4_ACL_NOT_CACHED;
 569 #endif
 570         ei->i_block_alloc_info = NULL;
 571         ei->vfs_inode.i_version = 1;
 572         ei->vfs_inode.i_data.writeback_index = 0;
 573         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 574         INIT_LIST_HEAD(&ei->i_prealloc_list);
 575         spin_lock_init(&ei->i_prealloc_lock);
 576         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
 577         ei->i_reserved_data_blocks = 0;
 578         ei->i_reserved_meta_blocks = 0;
 579         ei->i_allocated_meta_blocks = 0;
 580         ei->i_delalloc_reserved_flag = 0;
 581         spin_lock_init(&(ei->i_block_reservation_lock));
 582         return &ei->vfs_inode;
 583 }
 584
 585 static void ext4_destroy_inode(struct inode *inode)
 586 {
 587         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 588                 printk("EXT4 Inode %p: orphan list check failed!\n",
 589                         EXT4_I(inode));
 590                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 591                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 592                                 true);
 593                 dump_stack();
 594         }
 595         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 596 }
 597
 598 static void init_once(void *foo)
 599 {
 600         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 601
 602         INIT_LIST_HEAD(&ei->i_orphan);
 603 #ifdef CONFIG_EXT4DEV_FS_XATTR
 604         init_rwsem(&ei->xattr_sem);
 605 #endif
 606         init_rwsem(&ei->i_data_sem);
 607         inode_init_once(&ei->vfs_inode);
 608 }
 609
 610 static int init_inodecache(void)
 611 {
 612         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 613                                              sizeof(struct ext4_inode_info),
 614                                              0, (SLAB_RECLAIM_ACCOUNT|
 615                                                 SLAB_MEM_SPREAD),
 616                                              init_once);
 617         if (ext4_inode_cachep == NULL)
 618                 return -ENOMEM;
 619         return 0;
 620 }
 621
 622 static void destroy_inodecache(void)
 623 {
 624         kmem_cache_destroy(ext4_inode_cachep);
 625 }
 626
 627 static void ext4_clear_inode(struct inode *inode)
 628 {
 629         struct ext4_block_alloc_info *rsv = EXT4_I(inode)->i_block_alloc_info;
 630 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 631         if (EXT4_I(inode)->i_acl &&
 632                         EXT4_I(inode)->i_acl != EXT4_ACL_NOT_CACHED) {
 633                 posix_acl_release(EXT4_I(inode)->i_acl);
 634                 EXT4_I(inode)->i_acl = EXT4_ACL_NOT_CACHED;
 635         }
 636         if (EXT4_I(inode)->i_default_acl &&
 637                         EXT4_I(inode)->i_default_acl != EXT4_ACL_NOT_CACHED) {
 638                 posix_acl_release(EXT4_I(inode)->i_default_acl);
 639                 EXT4_I(inode)->i_default_acl = EXT4_ACL_NOT_CACHED;
 640         }
 641 #endif
 642         ext4_discard_reservation(inode);
 643         EXT4_I(inode)->i_block_alloc_info = NULL;
 644         if (unlikely(rsv))
 645                 kfree(rsv);
 646         jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
 647                                        &EXT4_I(inode)->jinode);
 648 }
 649
 650 static inline void ext4_show_quota_options(struct seq_file *seq,
 651                                            struct super_block *sb)
 652 {
 653 #if defined(CONFIG_QUOTA)
 654         struct ext4_sb_info *sbi = EXT4_SB(sb);
 655
 656         if (sbi->s_jquota_fmt)
 657                 seq_printf(seq, ",jqfmt=%s",
 658                 (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold" : "vfsv0");
 659
 660         if (sbi->s_qf_names[USRQUOTA])
 661                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 662
 663         if (sbi->s_qf_names[GRPQUOTA])
 664                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 665
 666         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
 667                 seq_puts(seq, ",usrquota");
 668
 669         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
 670                 seq_puts(seq, ",grpquota");
 671 #endif
 672 }
 673
 674 /*
 675  * Show an option if
 676  *  - it's set to a non-default value OR
 677  *  - if the per-sb default is different from the global default
 678  */
 679 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 680 {
 681         int def_errors;
 682         unsigned long def_mount_opts;
 683         struct super_block *sb = vfs->mnt_sb;
 684         struct ext4_sb_info *sbi = EXT4_SB(sb);
 685         struct ext4_super_block *es = sbi->s_es;
 686
 687         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 688         def_errors     = le16_to_cpu(es->s_errors);
 689
 690         if (sbi->s_sb_block != 1)
 691                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
 692         if (test_opt(sb, MINIX_DF))
 693                 seq_puts(seq, ",minixdf");
 694         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
 695                 seq_puts(seq, ",grpid");
 696         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
 697                 seq_puts(seq, ",nogrpid");
 698         if (sbi->s_resuid != EXT4_DEF_RESUID ||
 699             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
 700                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
 701         }
 702         if (sbi->s_resgid != EXT4_DEF_RESGID ||
 703             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
 704                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
 705         }
 706         if (test_opt(sb, ERRORS_RO)) {
 707                 if (def_errors == EXT4_ERRORS_PANIC ||
 708                     def_errors == EXT4_ERRORS_CONTINUE) {
 709                         seq_puts(seq, ",errors=remount-ro");
 710                 }
 711         }
 712         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
 713                 seq_puts(seq, ",errors=continue");
 714         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
 715                 seq_puts(seq, ",errors=panic");
 716         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
 717                 seq_puts(seq, ",nouid32");
 718         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
 719                 seq_puts(seq, ",debug");
 720         if (test_opt(sb, OLDALLOC))
 721                 seq_puts(seq, ",oldalloc");
 722 #ifdef CONFIG_EXT4DEV_FS_XATTR
 723         if (test_opt(sb, XATTR_USER) &&
 724                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
 725                 seq_puts(seq, ",user_xattr");
 726         if (!test_opt(sb, XATTR_USER) &&
 727             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
 728                 seq_puts(seq, ",nouser_xattr");
 729         }
 730 #endif
 731 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 732         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
 733                 seq_puts(seq, ",acl");
 734         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
 735                 seq_puts(seq, ",noacl");
 736 #endif
 737         if (!test_opt(sb, RESERVATION))
 738                 seq_puts(seq, ",noreservation");
 739         if (sbi->s_commit_interval) {
 740                 seq_printf(seq, ",commit=%u",
 741                            (unsigned) (sbi->s_commit_interval / HZ));
 742         }
 743         /*
 744          * We're changing the default of barrier mount option, so
 745          * let's always display its mount state so it's clear what its
 746          * status is.
 747          */
 748         seq_puts(seq, ",barrier=");
 749         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
 750         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
 751                 seq_puts(seq, ",journal_async_commit");
 752         if (test_opt(sb, NOBH))
 753                 seq_puts(seq, ",nobh");
 754         if (!test_opt(sb, EXTENTS))
 755                 seq_puts(seq, ",noextents");
 756         if (!test_opt(sb, MBALLOC))
 757                 seq_puts(seq, ",nomballoc");
 758         if (test_opt(sb, I_VERSION))
 759                 seq_puts(seq, ",i_version");
 760         if (!test_opt(sb, DELALLOC))
 761                 seq_puts(seq, ",nodelalloc");
 762
 763
 764         if (sbi->s_stripe)
 765                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
 766         /*
 767          * journal mode get enabled in different ways
 768          * So just print the value even if we didn't specify it
 769          */
 770         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 771                 seq_puts(seq, ",data=journal");
 772         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 773                 seq_puts(seq, ",data=ordered");
 774         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 775                 seq_puts(seq, ",data=writeback");
 776
 777         ext4_show_quota_options(seq, sb);
 778         return 0;
 779 }
 780
 781
 782 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 783                 u64 ino, u32 generation)
 784 {
 785         struct inode *inode;
 786
 787         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 788                 return ERR_PTR(-ESTALE);
 789         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 790                 return ERR_PTR(-ESTALE);
 791
 792         /* iget isn't really right if the inode is currently unallocated!!
 793          *
 794          * ext4_read_inode will return a bad_inode if the inode had been
 795          * deleted, so we should be safe.
 796          *
 797          * Currently we don't know the generation for parent directory, so
 798          * a generation of 0 means "accept any"
 799          */
 800         inode = ext4_iget(sb, ino);
 801         if (IS_ERR(inode))
 802                 return ERR_CAST(inode);
 803         if (generation && inode->i_generation != generation) {
 804                 iput(inode);
 805                 return ERR_PTR(-ESTALE);
 806         }
 807
 808         return inode;
 809 }
 810
 811 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
 812                 int fh_len, int fh_type)
 813 {
 814         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 815                                     ext4_nfs_get_inode);
 816 }
 817
 818 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
 819                 int fh_len, int fh_type)
 820 {
 821         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 822                                     ext4_nfs_get_inode);
 823 }
 824
 825 #ifdef CONFIG_QUOTA
 826 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
 827 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
 828
 829 static int ext4_dquot_initialize(struct inode *inode, int type);
 830 static int ext4_dquot_drop(struct inode *inode);
 831 static int ext4_write_dquot(struct dquot *dquot);
 832 static int ext4_acquire_dquot(struct dquot *dquot);
 833 static int ext4_release_dquot(struct dquot *dquot);
 834 static int ext4_mark_dquot_dirty(struct dquot *dquot);
 835 static int ext4_write_info(struct super_block *sb, int type);
 836 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
 837                                 char *path, int remount);
 838 static int ext4_quota_on_mount(struct super_block *sb, int type);
 839 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
 840                                size_t len, loff_t off);
 841 static ssize_t ext4_quota_write(struct super_block *sb, int type,
 842                                 const char *data, size_t len, loff_t off);
 843
 844 static struct dquot_operations ext4_quota_operations = {
 845         .initialize     = ext4_dquot_initialize,
 846         .drop           = ext4_dquot_drop,
 847         .alloc_space    = dquot_alloc_space,
 848         .alloc_inode    = dquot_alloc_inode,
 849         .free_space     = dquot_free_space,
 850         .free_inode     = dquot_free_inode,
 851         .transfer       = dquot_transfer,
 852         .write_dquot    = ext4_write_dquot,
 853         .acquire_dquot  = ext4_acquire_dquot,
 854         .release_dquot  = ext4_release_dquot,
 855         .mark_dirty     = ext4_mark_dquot_dirty,
 856         .write_info     = ext4_write_info
 857 };
 858
 859 static struct quotactl_ops ext4_qctl_operations = {
 860         .quota_on       = ext4_quota_on,
 861         .quota_off      = vfs_quota_off,
 862         .quota_sync     = vfs_quota_sync,
 863         .get_info       = vfs_get_dqinfo,
 864         .set_info       = vfs_set_dqinfo,
 865         .get_dqblk      = vfs_get_dqblk,
 866         .set_dqblk      = vfs_set_dqblk
 867 };
 868 #endif
 869
 870 static const struct super_operations ext4_sops = {
 871         .alloc_inode    = ext4_alloc_inode,
 872         .destroy_inode  = ext4_destroy_inode,
 873         .write_inode    = ext4_write_inode,
 874         .dirty_inode    = ext4_dirty_inode,
 875         .delete_inode   = ext4_delete_inode,
 876         .put_super      = ext4_put_super,
 877         .write_super    = ext4_write_super,
 878         .sync_fs        = ext4_sync_fs,
 879         .write_super_lockfs = ext4_write_super_lockfs,
 880         .unlockfs       = ext4_unlockfs,
 881         .statfs         = ext4_statfs,
 882         .remount_fs     = ext4_remount,
 883         .clear_inode    = ext4_clear_inode,
 884         .show_options   = ext4_show_options,
 885 #ifdef CONFIG_QUOTA
 886         .quota_read     = ext4_quota_read,
 887         .quota_write    = ext4_quota_write,
 888 #endif
 889 };
 890
 891 static const struct export_operations ext4_export_ops = {
 892         .fh_to_dentry = ext4_fh_to_dentry,
 893         .fh_to_parent = ext4_fh_to_parent,
 894         .get_parent = ext4_get_parent,
 895 };
 896
 897 enum {
 898         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
 899         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
 900         Opt_nouid32, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov,
 901         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
 902         Opt_reservation, Opt_noreservation, Opt_noload, Opt_nobh, Opt_bh,
 903         Opt_commit, Opt_journal_update, Opt_journal_inum, Opt_journal_dev,
 904         Opt_journal_checksum, Opt_journal_async_commit,
 905         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
 906         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
 907         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
 908         Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
 909         Opt_grpquota, Opt_extents, Opt_noextents, Opt_i_version,
 910         Opt_mballoc, Opt_nomballoc, Opt_stripe, Opt_delalloc, Opt_nodelalloc,
 911 };
 912
 913 static match_table_t tokens = {
 914         {Opt_bsd_df, "bsddf"},
 915         {Opt_minix_df, "minixdf"},
 916         {Opt_grpid, "grpid"},
 917         {Opt_grpid, "bsdgroups"},
 918         {Opt_nogrpid, "nogrpid"},
 919         {Opt_nogrpid, "sysvgroups"},
 920         {Opt_resgid, "resgid=%u"},
 921         {Opt_resuid, "resuid=%u"},
 922         {Opt_sb, "sb=%u"},
 923         {Opt_err_cont, "errors=continue"},
 924         {Opt_err_panic, "errors=panic"},
 925         {Opt_err_ro, "errors=remount-ro"},
 926         {Opt_nouid32, "nouid32"},
 927         {Opt_nocheck, "nocheck"},
 928         {Opt_nocheck, "check=none"},
 929         {Opt_debug, "debug"},
 930         {Opt_oldalloc, "oldalloc"},
 931         {Opt_orlov, "orlov"},
 932         {Opt_user_xattr, "user_xattr"},
 933         {Opt_nouser_xattr, "nouser_xattr"},
 934         {Opt_acl, "acl"},
 935         {Opt_noacl, "noacl"},
 936         {Opt_reservation, "reservation"},
 937         {Opt_noreservation, "noreservation"},
 938         {Opt_noload, "noload"},
 939         {Opt_nobh, "nobh"},
 940         {Opt_bh, "bh"},
 941         {Opt_commit, "commit=%u"},
 942         {Opt_journal_update, "journal=update"},
 943         {Opt_journal_inum, "journal=%u"},
 944         {Opt_journal_dev, "journal_dev=%u"},
 945         {Opt_journal_checksum, "journal_checksum"},
 946         {Opt_journal_async_commit, "journal_async_commit"},
 947         {Opt_abort, "abort"},
 948         {Opt_data_journal, "data=journal"},
 949         {Opt_data_ordered, "data=ordered"},
 950         {Opt_data_writeback, "data=writeback"},
 951         {Opt_offusrjquota, "usrjquota="},
 952         {Opt_usrjquota, "usrjquota=%s"},
 953         {Opt_offgrpjquota, "grpjquota="},
 954         {Opt_grpjquota, "grpjquota=%s"},
 955         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
 956         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
 957         {Opt_grpquota, "grpquota"},
 958         {Opt_noquota, "noquota"},
 959         {Opt_quota, "quota"},
 960         {Opt_usrquota, "usrquota"},
 961         {Opt_barrier, "barrier=%u"},
 962         {Opt_extents, "extents"},
 963         {Opt_noextents, "noextents"},
 964         {Opt_i_version, "i_version"},
 965         {Opt_mballoc, "mballoc"},
 966         {Opt_nomballoc, "nomballoc"},
 967         {Opt_stripe, "stripe=%u"},
 968         {Opt_resize, "resize"},
 969         {Opt_delalloc, "delalloc"},
 970         {Opt_nodelalloc, "nodelalloc"},
 971         {Opt_err, NULL},
 972 };
 973
 974 static ext4_fsblk_t get_sb_block(void **data)
 975 {
 976         ext4_fsblk_t    sb_block;
 977         char            *options = (char *) *data;
 978
 979         if (!options || strncmp(options, "sb=", 3) != 0)
 980                 return 1;       /* Default location */
 981         options += 3;
 982         /*todo: use simple_strtoll with >32bit ext4 */
 983         sb_block = simple_strtoul(options, &options, 0);
 984         if (*options && *options != ',') {
 985                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
 986                        (char *) *data);
 987                 return 1;
 988         }
 989         if (*options == ',')
 990                 options++;
 991         *data = (void *) options;
 992         return sb_block;
 993 }
 994
 995 static int parse_options(char *options, struct super_block *sb,
 996                          unsigned int *inum, unsigned long *journal_devnum,
 997                          ext4_fsblk_t *n_blocks_count, int is_remount)
 998 {
 999         struct ext4_sb_info *sbi = EXT4_SB(sb);
1000         char *p;
1001         substring_t args[MAX_OPT_ARGS];
1002         int data_opt = 0;
1003         int option;
1004 #ifdef CONFIG_QUOTA
1005         int qtype, qfmt;
1006         char *qname;
1007 #endif
1008         ext4_fsblk_t last_block;
1009
1010         if (!options)
1011                 return 1;
1012
1013         while ((p = strsep(&options, ",")) != NULL) {
1014                 int token;
1015                 if (!*p)
1016                         continue;
1017
1018                 token = match_token(p, tokens, args);
1019                 switch (token) {
1020                 case Opt_bsd_df:
1021                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1022                         break;
1023                 case Opt_minix_df:
1024                         set_opt(sbi->s_mount_opt, MINIX_DF);
1025                         break;
1026                 case Opt_grpid:
1027                         set_opt(sbi->s_mount_opt, GRPID);
1028                         break;
1029                 case Opt_nogrpid:
1030                         clear_opt(sbi->s_mount_opt, GRPID);
1031                         break;
1032                 case Opt_resuid:
1033                         if (match_int(&args[0], &option))
1034                                 return 0;
1035                         sbi->s_resuid = option;
1036                         break;
1037                 case Opt_resgid:
1038                         if (match_int(&args[0], &option))
1039                                 return 0;
1040                         sbi->s_resgid = option;
1041                         break;
1042                 case Opt_sb:
1043                         /* handled by get_sb_block() instead of here */
1044                         /* *sb_block = match_int(&args[0]); */
1045                         break;
1046                 case Opt_err_panic:
1047                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1048                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1049                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1050                         break;
1051                 case Opt_err_ro:
1052                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1053                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1054                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1055                         break;
1056                 case Opt_err_cont:
1057                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1058                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1059                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1060                         break;
1061                 case Opt_nouid32:
1062                         set_opt(sbi->s_mount_opt, NO_UID32);
1063                         break;
1064                 case Opt_nocheck:
1065                         clear_opt(sbi->s_mount_opt, CHECK);
1066                         break;
1067                 case Opt_debug:
1068                         set_opt(sbi->s_mount_opt, DEBUG);
1069                         break;
1070                 case Opt_oldalloc:
1071                         set_opt(sbi->s_mount_opt, OLDALLOC);
1072                         break;
1073                 case Opt_orlov:
1074                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1075                         break;
1076 #ifdef CONFIG_EXT4DEV_FS_XATTR
1077                 case Opt_user_xattr:
1078                         set_opt(sbi->s_mount_opt, XATTR_USER);
1079                         break;
1080                 case Opt_nouser_xattr:
1081                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1082                         break;
1083 #else
1084                 case Opt_user_xattr:
1085                 case Opt_nouser_xattr:
1086                         printk(KERN_ERR "EXT4 (no)user_xattr options "
1087                                "not supported\n");
1088                         break;
1089 #endif
1090 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
1091                 case Opt_acl:
1092                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1093                         break;
1094                 case Opt_noacl:
1095                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1096                         break;
1097 #else
1098                 case Opt_acl:
1099                 case Opt_noacl:
1100                         printk(KERN_ERR "EXT4 (no)acl options "
1101                                "not supported\n");
1102                         break;
1103 #endif
1104                 case Opt_reservation:
1105                         set_opt(sbi->s_mount_opt, RESERVATION);
1106                         break;
1107                 case Opt_noreservation:
1108                         clear_opt(sbi->s_mount_opt, RESERVATION);
1109                         break;
1110                 case Opt_journal_update:
1111                         /* @@@ FIXME */
1112                         /* Eventually we will want to be able to create
1113                            a journal file here.  For now, only allow the
1114                            user to specify an existing inode to be the
1115                            journal file. */
1116                         if (is_remount) {
1117                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1118                                        "journal on remount\n");
1119                                 return 0;
1120                         }
1121                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1122                         break;
1123                 case Opt_journal_inum:
1124                         if (is_remount) {
1125                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1126                                        "journal on remount\n");
1127                                 return 0;
1128                         }
1129                         if (match_int(&args[0], &option))
1130                                 return 0;
1131                         *inum = option;
1132                         break;
1133                 case Opt_journal_dev:
1134                         if (is_remount) {
1135                                 printk(KERN_ERR "EXT4-fs: cannot specify "
1136                                        "journal on remount\n");
1137                                 return 0;
1138                         }
1139                         if (match_int(&args[0], &option))
1140                                 return 0;
1141                         *journal_devnum = option;
1142                         break;
1143                 case Opt_journal_checksum:
1144                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1145                         break;
1146                 case Opt_journal_async_commit:
1147                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1148                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1149                         break;
1150                 case Opt_noload:
1151                         set_opt(sbi->s_mount_opt, NOLOAD);
1152                         break;
1153                 case Opt_commit:
1154                         if (match_int(&args[0], &option))
1155                                 return 0;
1156                         if (option < 0)
1157                                 return 0;
1158                         if (option == 0)
1159                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1160                         sbi->s_commit_interval = HZ * option;
1161                         break;
1162                 case Opt_data_journal:
1163                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1164                         goto datacheck;
1165                 case Opt_data_ordered:
1166                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1167                         goto datacheck;
1168                 case Opt_data_writeback:
1169                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1170                 datacheck:
1171                         if (is_remount) {
1172                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1173                                                 != data_opt) {
1174                                         printk(KERN_ERR
1175                                                 "EXT4-fs: cannot change data "
1176                                                 "mode on remount\n");
1177                                         return 0;
1178                                 }
1179                         } else {
1180                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1181                                 sbi->s_mount_opt |= data_opt;
1182                         }
1183                         break;
1184 #ifdef CONFIG_QUOTA
1185                 case Opt_usrjquota:
1186                         qtype = USRQUOTA;
1187                         goto set_qf_name;
1188                 case Opt_grpjquota:
1189                         qtype = GRPQUOTA;
1190 set_qf_name:
1191                         if ((sb_any_quota_enabled(sb) ||
1192                              sb_any_quota_suspended(sb)) &&
1193                             !sbi->s_qf_names[qtype]) {
1194                                 printk(KERN_ERR
1195                                        "EXT4-fs: Cannot change journaled "
1196                                        "quota options when quota turned on.\n");
1197                                 return 0;
1198                         }
1199                         qname = match_strdup(&args[0]);
1200                         if (!qname) {
1201                                 printk(KERN_ERR
1202                                         "EXT4-fs: not enough memory for "
1203                                         "storing quotafile name.\n");
1204                                 return 0;
1205                         }
1206                         if (sbi->s_qf_names[qtype] &&
1207                             strcmp(sbi->s_qf_names[qtype], qname)) {
1208                                 printk(KERN_ERR
1209                                         "EXT4-fs: %s quota file already "
1210                                         "specified.\n", QTYPE2NAME(qtype));
1211                                 kfree(qname);
1212                                 return 0;
1213                         }
1214                         sbi->s_qf_names[qtype] = qname;
1215                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1216                                 printk(KERN_ERR
1217                                         "EXT4-fs: quotafile must be on "
1218                                         "filesystem root.\n");
1219                                 kfree(sbi->s_qf_names[qtype]);
1220                                 sbi->s_qf_names[qtype] = NULL;
1221                                 return 0;
1222                         }
1223                         set_opt(sbi->s_mount_opt, QUOTA);
1224                         break;
1225                 case Opt_offusrjquota:
1226                         qtype = USRQUOTA;
1227                         goto clear_qf_name;
1228                 case Opt_offgrpjquota:
1229                         qtype = GRPQUOTA;
1230 clear_qf_name:
1231                         if ((sb_any_quota_enabled(sb) ||
1232                              sb_any_quota_suspended(sb)) &&
1233                             sbi->s_qf_names[qtype]) {
1234                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1235                                         "journaled quota options when "
1236                                         "quota turned on.\n");
1237                                 return 0;
1238                         }
1239                         /*
1240                          * The space will be released later when all options
1241                          * are confirmed to be correct
1242                          */
1243                         sbi->s_qf_names[qtype] = NULL;
1244                         break;
1245                 case Opt_jqfmt_vfsold:
1246                         qfmt = QFMT_VFS_OLD;
1247                         goto set_qf_format;
1248                 case Opt_jqfmt_vfsv0:
1249                         qfmt = QFMT_VFS_V0;
1250 set_qf_format:
1251                         if ((sb_any_quota_enabled(sb) ||
1252                              sb_any_quota_suspended(sb)) &&
1253                             sbi->s_jquota_fmt != qfmt) {
1254                                 printk(KERN_ERR "EXT4-fs: Cannot change "
1255                                         "journaled quota options when "
1256                                         "quota turned on.\n");
1257                                 return 0;
1258                         }
1259                         sbi->s_jquota_fmt = qfmt;
1260                         break;
1261                 case Opt_quota:
1262                 case Opt_usrquota:
1263                         set_opt(sbi->s_mount_opt, QUOTA);
1264                         set_opt(sbi->s_mount_opt, USRQUOTA);
1265                         break;
1266                 case Opt_grpquota:
1267                         set_opt(sbi->s_mount_opt, QUOTA);
1268                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1269                         break;
1270                 case Opt_noquota:
1271                         if (sb_any_quota_enabled(sb)) {
1272                                 printk(KERN_ERR "EXT4-fs: Cannot change quota "
1273                                         "options when quota turned on.\n");
1274                                 return 0;
1275                         }
1276                         clear_opt(sbi->s_mount_opt, QUOTA);
1277                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1278                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1279                         break;
1280 #else
1281                 case Opt_quota:
1282                 case Opt_usrquota:
1283                 case Opt_grpquota:
1284                         printk(KERN_ERR
1285                                 "EXT4-fs: quota options not supported.\n");
1286                         break;
1287                 case Opt_usrjquota:
1288                 case Opt_grpjquota:
1289                 case Opt_offusrjquota:
1290                 case Opt_offgrpjquota:
1291                 case Opt_jqfmt_vfsold:
1292                 case Opt_jqfmt_vfsv0:
1293                         printk(KERN_ERR
1294                                 "EXT4-fs: journaled quota options not "
1295                                 "supported.\n");
1296                         break;
1297                 case Opt_noquota:
1298                         break;
1299 #endif
1300                 case Opt_abort:
1301                         set_opt(sbi->s_mount_opt, ABORT);
1302                         break;
1303                 case Opt_barrier:
1304                         if (match_int(&args[0], &option))
1305                                 return 0;
1306                         if (option)
1307                                 set_opt(sbi->s_mount_opt, BARRIER);
1308                         else
1309                                 clear_opt(sbi->s_mount_opt, BARRIER);
1310                         break;
1311                 case Opt_ignore:
1312                         break;
1313                 case Opt_resize:
1314                         if (!is_remount) {
1315                                 printk("EXT4-fs: resize option only available "
1316                                         "for remount\n");
1317                                 return 0;
1318                         }
1319                         if (match_int(&args[0], &option) != 0)
1320                                 return 0;
1321                         *n_blocks_count = option;
1322                         break;
1323                 case Opt_nobh:
1324                         set_opt(sbi->s_mount_opt, NOBH);
1325                         break;
1326                 case Opt_bh:
1327                         clear_opt(sbi->s_mount_opt, NOBH);
1328                         break;
1329                 case Opt_extents:
1330                         if (!EXT4_HAS_INCOMPAT_FEATURE(sb,
1331                                         EXT4_FEATURE_INCOMPAT_EXTENTS)) {
1332                                 ext4_warning(sb, __func__,
1333                                         "extents feature not enabled "
1334                                         "on this filesystem, use tune2fs\n");
1335                                 return 0;
1336                         }
1337                         set_opt(sbi->s_mount_opt, EXTENTS);
1338                         break;
1339                 case Opt_noextents:
1340                         /*
1341                          * When e2fsprogs support resizing an already existing
1342                          * ext3 file system to greater than 2**32 we need to
1343                          * add support to block allocator to handle growing
1344                          * already existing block  mapped inode so that blocks
1345                          * allocated for them fall within 2**32
1346                          */
1347                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1348                         if (last_block  > 0xffffffffULL) {
1349                                 printk(KERN_ERR "EXT4-fs: Filesystem too "
1350                                                 "large to mount with "
1351                                                 "-o noextents options\n");
1352                                 return 0;
1353                         }
1354                         clear_opt(sbi->s_mount_opt, EXTENTS);
1355                         break;
1356                 case Opt_i_version:
1357                         set_opt(sbi->s_mount_opt, I_VERSION);
1358                         sb->s_flags |= MS_I_VERSION;
1359                         break;
1360                 case Opt_nodelalloc:
1361                         clear_opt(sbi->s_mount_opt, DELALLOC);
1362                         break;
1363                 case Opt_mballoc:
1364                         set_opt(sbi->s_mount_opt, MBALLOC);
1365                         break;
1366                 case Opt_nomballoc:
1367                         clear_opt(sbi->s_mount_opt, MBALLOC);
1368                         break;
1369                 case Opt_stripe:
1370                         if (match_int(&args[0], &option))
1371                                 return 0;
1372                         if (option < 0)
1373                                 return 0;
1374                         sbi->s_stripe = option;
1375                         break;
1376                 case Opt_delalloc:
1377                         set_opt(sbi->s_mount_opt, DELALLOC);
1378                         break;
1379                 default:
1380                         printk(KERN_ERR
1381                                "EXT4-fs: Unrecognized mount option \"%s\" "
1382                                "or missing value\n", p);
1383                         return 0;
1384                 }
1385         }
1386 #ifdef CONFIG_QUOTA
1387         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1388                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1389                      sbi->s_qf_names[USRQUOTA])
1390                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1391
1392                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1393                      sbi->s_qf_names[GRPQUOTA])
1394                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1395
1396                 if ((sbi->s_qf_names[USRQUOTA] &&
1397                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1398                     (sbi->s_qf_names[GRPQUOTA] &&
1399                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1400                         printk(KERN_ERR "EXT4-fs: old and new quota "
1401                                         "format mixing.\n");
1402                         return 0;
1403                 }
1404
1405                 if (!sbi->s_jquota_fmt) {
1406                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1407                                         "not specified.\n");
1408                         return 0;
1409                 }
1410         } else {
1411                 if (sbi->s_jquota_fmt) {
1412                         printk(KERN_ERR "EXT4-fs: journaled quota format "
1413                                         "specified with no journaling "
1414                                         "enabled.\n");
1415                         return 0;
1416                 }
1417         }
1418 #endif
1419         return 1;
1420 }
1421
1422 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1423                             int read_only)
1424 {
1425         struct ext4_sb_info *sbi = EXT4_SB(sb);
1426         int res = 0;
1427
1428         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1429                 printk(KERN_ERR "EXT4-fs warning: revision level too high, "
1430                        "forcing read-only mode\n");
1431                 res = MS_RDONLY;
1432         }
1433         if (read_only)
1434                 return res;
1435         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1436                 printk(KERN_WARNING "EXT4-fs warning: mounting unchecked fs, "
1437                        "running e2fsck is recommended\n");
1438         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1439                 printk(KERN_WARNING
1440                        "EXT4-fs warning: mounting fs with errors, "
1441                        "running e2fsck is recommended\n");
1442         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1443                  le16_to_cpu(es->s_mnt_count) >=
1444                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1445                 printk(KERN_WARNING
1446                        "EXT4-fs warning: maximal mount count reached, "
1447                        "running e2fsck is recommended\n");
1448         else if (le32_to_cpu(es->s_checkinterval) &&
1449                 (le32_to_cpu(es->s_lastcheck) +
1450                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1451                 printk(KERN_WARNING
1452                        "EXT4-fs warning: checktime reached, "
1453                        "running e2fsck is recommended\n");
1454 #if 0
1455                 /* @@@ We _will_ want to clear the valid bit if we find
1456                  * inconsistencies, to force a fsck at reboot.  But for
1457                  * a plain journaled filesystem we can keep it set as
1458                  * valid forever! :)
1459                  */
1460         es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1461 #endif
1462         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1463                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1464         le16_add_cpu(&es->s_mnt_count, 1);
1465         es->s_mtime = cpu_to_le32(get_seconds());
1466         ext4_update_dynamic_rev(sb);
1467         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1468
1469         ext4_commit_super(sb, es, 1);
1470         if (test_opt(sb, DEBUG))
1471                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%lu, "
1472                                 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
1473                         sb->s_blocksize,
1474                         sbi->s_groups_count,
1475                         EXT4_BLOCKS_PER_GROUP(sb),
1476                         EXT4_INODES_PER_GROUP(sb),
1477                         sbi->s_mount_opt);
1478
1479         if (EXT4_SB(sb)->s_journal->j_inode == NULL) {
1480                 char b[BDEVNAME_SIZE];
1481
1482                 printk(KERN_INFO "EXT4 FS on %s, external journal on %s\n",
1483                        sb->s_id, bdevname(EXT4_SB(sb)->s_journal->j_dev, b));
1484         } else {
1485                 printk(KERN_INFO "EXT4 FS on %s, internal journal\n",
1486                        sb->s_id);
1487         }
1488         return res;
1489 }
1490
1491 static int ext4_fill_flex_info(struct super_block *sb)
1492 {
1493         struct ext4_sb_info *sbi = EXT4_SB(sb);
1494         struct ext4_group_desc *gdp = NULL;
1495         struct buffer_head *bh;
1496         ext4_group_t flex_group_count;
1497         ext4_group_t flex_group;
1498         int groups_per_flex = 0;
1499         __u64 block_bitmap = 0;
1500         int i;
1501
1502         if (!sbi->s_es->s_log_groups_per_flex) {
1503                 sbi->s_log_groups_per_flex = 0;
1504                 return 1;
1505         }
1506
1507         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1508         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1509
1510         flex_group_count = (sbi->s_groups_count + groups_per_flex - 1) /
1511                 groups_per_flex;
1512         sbi->s_flex_groups = kzalloc(flex_group_count *
1513                                      sizeof(struct flex_groups), GFP_KERNEL);
1514         if (sbi->s_flex_groups == NULL) {
1515                 printk(KERN_ERR "EXT4-fs: not enough memory for "
1516                                 "%lu flex groups\n", flex_group_count);
1517                 goto failed;
1518         }
1519
1520         gdp = ext4_get_group_desc(sb, 1, &bh);
1521         block_bitmap = ext4_block_bitmap(sb, gdp) - 1;
1522
1523         for (i = 0; i < sbi->s_groups_count; i++) {
1524                 gdp = ext4_get_group_desc(sb, i, &bh);
1525
1526                 flex_group = ext4_flex_group(sbi, i);
1527                 sbi->s_flex_groups[flex_group].free_inodes +=
1528                         le16_to_cpu(gdp->bg_free_inodes_count);
1529                 sbi->s_flex_groups[flex_group].free_blocks +=
1530                         le16_to_cpu(gdp->bg_free_blocks_count);
1531         }
1532
1533         return 1;
1534 failed:
1535         return 0;
1536 }
1537
1538 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1539                             struct ext4_group_desc *gdp)
1540 {
1541         __u16 crc = 0;
1542
1543         if (sbi->s_es->s_feature_ro_compat &
1544             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1545                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1546                 __le32 le_group = cpu_to_le32(block_group);
1547
1548                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1549                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1550                 crc = crc16(crc, (__u8 *)gdp, offset);
1551                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1552                 /* for checksum of struct ext4_group_desc do the rest...*/
1553                 if ((sbi->s_es->s_feature_incompat &
1554                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1555                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1556                         crc = crc16(crc, (__u8 *)gdp + offset,
1557                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1558                                         offset);
1559         }
1560
1561         return cpu_to_le16(crc);
1562 }
1563
1564 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1565                                 struct ext4_group_desc *gdp)
1566 {
1567         if ((sbi->s_es->s_feature_ro_compat &
1568              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1569             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1570                 return 0;
1571
1572         return 1;
1573 }
1574
1575 /* Called at mount-time, super-block is locked */
1576 static int ext4_check_descriptors(struct super_block *sb)
1577 {
1578         struct ext4_sb_info *sbi = EXT4_SB(sb);
1579         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1580         ext4_fsblk_t last_block;
1581         ext4_fsblk_t block_bitmap;
1582         ext4_fsblk_t inode_bitmap;
1583         ext4_fsblk_t inode_table;
1584         int flexbg_flag = 0;
1585         ext4_group_t i;
1586
1587         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1588                 flexbg_flag = 1;
1589
1590         ext4_debug("Checking group descriptors");
1591
1592         for (i = 0; i < sbi->s_groups_count; i++) {
1593                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1594
1595                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1596                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1597                 else
1598                         last_block = first_block +
1599                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1600
1601                 block_bitmap = ext4_block_bitmap(sb, gdp);
1602                 if (block_bitmap < first_block || block_bitmap > last_block) {
1603                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1604                                "Block bitmap for group %lu not in group "
1605                                "(block %llu)!", i, block_bitmap);
1606                         return 0;
1607                 }
1608                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1609                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1610                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1611                                "Inode bitmap for group %lu not in group "
1612                                "(block %llu)!", i, inode_bitmap);
1613                         return 0;
1614                 }
1615                 inode_table = ext4_inode_table(sb, gdp);
1616                 if (inode_table < first_block ||
1617                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1618                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1619                                "Inode table for group %lu not in group "
1620                                "(block %llu)!", i, inode_table);
1621                         return 0;
1622                 }
1623                 spin_lock(sb_bgl_lock(sbi, i));
1624                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1625                         printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: "
1626                                "Checksum for group %lu failed (%u!=%u)\n",
1627                                i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1628                                gdp)), le16_to_cpu(gdp->bg_checksum));
1629                         if (!(sb->s_flags & MS_RDONLY))
1630                                 return 0;
1631                 }
1632                 spin_unlock(sb_bgl_lock(sbi, i));
1633                 if (!flexbg_flag)
1634                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1635         }
1636
1637         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1638         sbi->s_es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
1639         return 1;
1640 }
1641
1642 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1643  * the superblock) which were deleted from all directories, but held open by
1644  * a process at the time of a crash.  We walk the list and try to delete these
1645  * inodes at recovery time (only with a read-write filesystem).
1646  *
1647  * In order to keep the orphan inode chain consistent during traversal (in
1648  * case of crash during recovery), we link each inode into the superblock
1649  * orphan list_head and handle it the same way as an inode deletion during
1650  * normal operation (which journals the operations for us).
1651  *
1652  * We only do an iget() and an iput() on each inode, which is very safe if we
1653  * accidentally point at an in-use or already deleted inode.  The worst that
1654  * can happen in this case is that we get a "bit already cleared" message from
1655  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1656  * e2fsck was run on this filesystem, and it must have already done the orphan
1657  * inode cleanup for us, so we can safely abort without any further action.
1658  */
1659 static void ext4_orphan_cleanup(struct super_block *sb,
1660                                 struct ext4_super_block *es)
1661 {
1662         unsigned int s_flags = sb->s_flags;
1663         int nr_orphans = 0, nr_truncates = 0;
1664 #ifdef CONFIG_QUOTA
1665         int i;
1666 #endif
1667         if (!es->s_last_orphan) {
1668                 jbd_debug(4, "no orphan inodes to clean up\n");
1669                 return;
1670         }
1671
1672         if (bdev_read_only(sb->s_bdev)) {
1673                 printk(KERN_ERR "EXT4-fs: write access "
1674                         "unavailable, skipping orphan cleanup.\n");
1675                 return;
1676         }
1677
1678         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1679                 if (es->s_last_orphan)
1680                         jbd_debug(1, "Errors on filesystem, "
1681                                   "clearing orphan list.\n");
1682                 es->s_last_orphan = 0;
1683                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1684                 return;
1685         }
1686
1687         if (s_flags & MS_RDONLY) {
1688                 printk(KERN_INFO "EXT4-fs: %s: orphan cleanup on readonly fs\n",
1689                        sb->s_id);
1690                 sb->s_flags &= ~MS_RDONLY;
1691         }
1692 #ifdef CONFIG_QUOTA
1693         /* Needed for iput() to work correctly and not trash data */
1694         sb->s_flags |= MS_ACTIVE;
1695         /* Turn on quotas so that they are updated correctly */
1696         for (i = 0; i < MAXQUOTAS; i++) {
1697                 if (EXT4_SB(sb)->s_qf_names[i]) {
1698                         int ret = ext4_quota_on_mount(sb, i);
1699                         if (ret < 0)
1700                                 printk(KERN_ERR
1701                                         "EXT4-fs: Cannot turn on journaled "
1702                                         "quota: error %d\n", ret);
1703                 }
1704         }
1705 #endif
1706
1707         while (es->s_last_orphan) {
1708                 struct inode *inode;
1709
1710                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1711                 if (IS_ERR(inode)) {
1712                         es->s_last_orphan = 0;
1713                         break;
1714                 }
1715
1716                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1717                 DQUOT_INIT(inode);
1718                 if (inode->i_nlink) {
1719                         printk(KERN_DEBUG
1720                                 "%s: truncating inode %lu to %lld bytes\n",
1721                                 __func__, inode->i_ino, inode->i_size);
1722                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1723                                   inode->i_ino, inode->i_size);
1724                         ext4_truncate(inode);
1725                         nr_truncates++;
1726                 } else {
1727                         printk(KERN_DEBUG
1728                                 "%s: deleting unreferenced inode %lu\n",
1729                                 __func__, inode->i_ino);
1730                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1731                                   inode->i_ino);
1732                         nr_orphans++;
1733                 }
1734                 iput(inode);  /* The delete magic happens here! */
1735         }
1736
1737 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1738
1739         if (nr_orphans)
1740                 printk(KERN_INFO "EXT4-fs: %s: %d orphan inode%s deleted\n",
1741                        sb->s_id, PLURAL(nr_orphans));
1742         if (nr_truncates)
1743                 printk(KERN_INFO "EXT4-fs: %s: %d truncate%s cleaned up\n",
1744                        sb->s_id, PLURAL(nr_truncates));
1745 #ifdef CONFIG_QUOTA
1746         /* Turn quotas off */
1747         for (i = 0; i < MAXQUOTAS; i++) {
1748                 if (sb_dqopt(sb)->files[i])
1749                         vfs_quota_off(sb, i, 0);
1750         }
1751 #endif
1752         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1753 }
1754 /*
1755  * Maximal extent format file size.
1756  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1757  * extent format containers, within a sector_t, and within i_blocks
1758  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1759  * so that won't be a limiting factor.
1760  *
1761  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1762  */
1763 static loff_t ext4_max_size(int blkbits)
1764 {
1765         loff_t res;
1766         loff_t upper_limit = MAX_LFS_FILESIZE;
1767
1768         /* small i_blocks in vfs inode? */
1769         if (sizeof(blkcnt_t) < sizeof(u64)) {
1770                 /*
1771                  * CONFIG_LSF is not enabled implies the inode
1772                  * i_block represent total blocks in 512 bytes
1773                  * 32 == size of vfs inode i_blocks * 8
1774                  */
1775                 upper_limit = (1LL << 32) - 1;
1776
1777                 /* total blocks in file system block size */
1778                 upper_limit >>= (blkbits - 9);
1779                 upper_limit <<= blkbits;
1780         }
1781
1782         /* 32-bit extent-start container, ee_block */
1783         res = 1LL << 32;
1784         res <<= blkbits;
1785         res -= 1;
1786
1787         /* Sanity check against vm- & vfs- imposed limits */
1788         if (res > upper_limit)
1789                 res = upper_limit;
1790
1791         return res;
1792 }
1793
1794 /*
1795  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
1796  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
1797  * We need to be 1 filesystem block less than the 2^48 sector limit.
1798  */
1799 static loff_t ext4_max_bitmap_size(int bits)
1800 {
1801         loff_t res = EXT4_NDIR_BLOCKS;
1802         int meta_blocks;
1803         loff_t upper_limit;
1804         /* This is calculated to be the largest file size for a
1805          * dense, bitmapped file such that the total number of
1806          * sectors in the file, including data and all indirect blocks,
1807          * does not exceed 2^48 -1
1808          * __u32 i_blocks_lo and _u16 i_blocks_high representing the
1809          * total number of  512 bytes blocks of the file
1810          */
1811
1812         if (sizeof(blkcnt_t) < sizeof(u64)) {
1813                 /*
1814                  * CONFIG_LSF is not enabled implies the inode
1815                  * i_block represent total blocks in 512 bytes
1816                  * 32 == size of vfs inode i_blocks * 8
1817                  */
1818                 upper_limit = (1LL << 32) - 1;
1819
1820                 /* total blocks in file system block size */
1821                 upper_limit >>= (bits - 9);
1822
1823         } else {
1824                 /*
1825                  * We use 48 bit ext4_inode i_blocks
1826                  * With EXT4_HUGE_FILE_FL set the i_blocks
1827                  * represent total number of blocks in
1828                  * file system block size
1829                  */
1830                 upper_limit = (1LL << 48) - 1;
1831
1832         }
1833
1834         /* indirect blocks */
1835         meta_blocks = 1;
1836         /* double indirect blocks */
1837         meta_blocks += 1 + (1LL << (bits-2));
1838         /* tripple indirect blocks */
1839         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
1840
1841         upper_limit -= meta_blocks;
1842         upper_limit <<= bits;
1843
1844         res += 1LL << (bits-2);
1845         res += 1LL << (2*(bits-2));
1846         res += 1LL << (3*(bits-2));
1847         res <<= bits;
1848         if (res > upper_limit)
1849                 res = upper_limit;
1850
1851         if (res > MAX_LFS_FILESIZE)
1852                 res = MAX_LFS_FILESIZE;
1853
1854         return res;
1855 }
1856
1857 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
1858                                 ext4_fsblk_t logical_sb_block, int nr)
1859 {
1860         struct ext4_sb_info *sbi = EXT4_SB(sb);
1861         ext4_group_t bg, first_meta_bg;
1862         int has_super = 0;
1863
1864         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
1865
1866         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
1867             nr < first_meta_bg)
1868                 return logical_sb_block + nr + 1;
1869         bg = sbi->s_desc_per_block * nr;
1870         if (ext4_bg_has_super(sb, bg))
1871                 has_super = 1;
1872         return (has_super + ext4_group_first_block_no(sb, bg));
1873 }
1874
1875 /**
1876  * ext4_get_stripe_size: Get the stripe size.
1877  * @sbi: In memory super block info
1878  *
1879  * If we have specified it via mount option, then
1880  * use the mount option value. If the value specified at mount time is
1881  * greater than the blocks per group use the super block value.
1882  * If the super block value is greater than blocks per group return 0.
1883  * Allocator needs it be less than blocks per group.
1884  *
1885  */
1886 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
1887 {
1888         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
1889         unsigned long stripe_width =
1890                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
1891
1892         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
1893                 return sbi->s_stripe;
1894
1895         if (stripe_width <= sbi->s_blocks_per_group)
1896                 return stripe_width;
1897
1898         if (stride <= sbi->s_blocks_per_group)
1899                 return stride;
1900
1901         return 0;
1902 }
1903
1904 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
1905                                 __releases(kernel_lock)
1906                                 __acquires(kernel_lock)
1907
1908 {
1909         struct buffer_head *bh;
1910         struct ext4_super_block *es = NULL;
1911         struct ext4_sb_info *sbi;
1912         ext4_fsblk_t block;
1913         ext4_fsblk_t sb_block = get_sb_block(&data);
1914         ext4_fsblk_t logical_sb_block;
1915         unsigned long offset = 0;
1916         unsigned int journal_inum = 0;
1917         unsigned long journal_devnum = 0;
1918         unsigned long def_mount_opts;
1919         struct inode *root;
1920         int ret = -EINVAL;
1921         int blocksize;
1922         int db_count;
1923         int i;
1924         int needs_recovery;
1925         __le32 features;
1926         __u64 blocks_count;
1927         int err;
1928
1929         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
1930         if (!sbi)
1931                 return -ENOMEM;
1932         sb->s_fs_info = sbi;
1933         sbi->s_mount_opt = 0;
1934         sbi->s_resuid = EXT4_DEF_RESUID;
1935         sbi->s_resgid = EXT4_DEF_RESGID;
1936         sbi->s_sb_block = sb_block;
1937
1938         unlock_kernel();
1939
1940         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
1941         if (!blocksize) {
1942                 printk(KERN_ERR "EXT4-fs: unable to set blocksize\n");
1943                 goto out_fail;
1944         }
1945
1946         /*
1947          * The ext4 superblock will not be buffer aligned for other than 1kB
1948          * block sizes.  We need to calculate the offset from buffer start.
1949          */
1950         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
1951                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
1952                 offset = do_div(logical_sb_block, blocksize);
1953         } else {
1954                 logical_sb_block = sb_block;
1955         }
1956
1957         if (!(bh = sb_bread(sb, logical_sb_block))) {
1958                 printk(KERN_ERR "EXT4-fs: unable to read superblock\n");
1959                 goto out_fail;
1960         }
1961         /*
1962          * Note: s_es must be initialized as soon as possible because
1963          *       some ext4 macro-instructions depend on its value
1964          */
1965         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
1966         sbi->s_es = es;
1967         sb->s_magic = le16_to_cpu(es->s_magic);
1968         if (sb->s_magic != EXT4_SUPER_MAGIC)
1969                 goto cantfind_ext4;
1970
1971         /* Set defaults before we parse the mount options */
1972         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
1973         if (def_mount_opts & EXT4_DEFM_DEBUG)
1974                 set_opt(sbi->s_mount_opt, DEBUG);
1975         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
1976                 set_opt(sbi->s_mount_opt, GRPID);
1977         if (def_mount_opts & EXT4_DEFM_UID16)
1978                 set_opt(sbi->s_mount_opt, NO_UID32);
1979 #ifdef CONFIG_EXT4DEV_FS_XATTR
1980         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
1981                 set_opt(sbi->s_mount_opt, XATTR_USER);
1982 #endif
1983 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
1984         if (def_mount_opts & EXT4_DEFM_ACL)
1985                 set_opt(sbi->s_mount_opt, POSIX_ACL);
1986 #endif
1987         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
1988                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
1989         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
1990                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
1991         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
1992                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
1993
1994         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
1995                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1996         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
1997                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
1998         else
1999                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2000
2001         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2002         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2003
2004         set_opt(sbi->s_mount_opt, RESERVATION);
2005         set_opt(sbi->s_mount_opt, BARRIER);
2006
2007         /*
2008          * turn on extents feature by default in ext4 filesystem
2009          * only if feature flag already set by mkfs or tune2fs.
2010          * Use -o noextents to turn it off
2011          */
2012         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
2013                 set_opt(sbi->s_mount_opt, EXTENTS);
2014         else
2015                 ext4_warning(sb, __func__,
2016                         "extents feature not enabled on this filesystem, "
2017                         "use tune2fs.\n");
2018         /*
2019          * turn on mballoc code by default in ext4 filesystem
2020          * Use -o nomballoc to turn it off
2021          */
2022         set_opt(sbi->s_mount_opt, MBALLOC);
2023
2024         /*
2025          * enable delayed allocation by default
2026          * Use -o nodelalloc to turn it off
2027          */
2028         set_opt(sbi->s_mount_opt, DELALLOC);
2029
2030
2031         if (!parse_options((char *) data, sb, &journal_inum, &journal_devnum,
2032                            NULL, 0))
2033                 goto failed_mount;
2034
2035         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2036                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2037
2038         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2039             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2040              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2041              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2042                 printk(KERN_WARNING
2043                        "EXT4-fs warning: feature flags set on rev 0 fs, "
2044                        "running e2fsck is recommended\n");
2045
2046         /*
2047          * Since ext4 is still considered development code, we require
2048          * that the TEST_FILESYS flag in s->flags be set.
2049          */
2050         if (!(le32_to_cpu(es->s_flags) & EXT2_FLAGS_TEST_FILESYS)) {
2051                 printk(KERN_WARNING "EXT4-fs: %s: not marked "
2052                        "OK to use with test code.\n", sb->s_id);
2053                 goto failed_mount;
2054         }
2055
2056         /*
2057          * Check feature flags regardless of the revision level, since we
2058          * previously didn't change the revision level when setting the flags,
2059          * so there is a chance incompat flags are set on a rev 0 filesystem.
2060          */
2061         features = EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP);
2062         if (features) {
2063                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount because of "
2064                        "unsupported optional features (%x).\n",
2065                        sb->s_id, le32_to_cpu(features));
2066                 goto failed_mount;
2067         }
2068         features = EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP);
2069         if (!(sb->s_flags & MS_RDONLY) && features) {
2070                 printk(KERN_ERR "EXT4-fs: %s: couldn't mount RDWR because of "
2071                        "unsupported optional features (%x).\n",
2072                        sb->s_id, le32_to_cpu(features));
2073                 goto failed_mount;
2074         }
2075         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2076                 /*
2077                  * Large file size enabled file system can only be
2078                  * mount if kernel is build with CONFIG_LSF
2079                  */
2080                 if (sizeof(root->i_blocks) < sizeof(u64) &&
2081                                 !(sb->s_flags & MS_RDONLY)) {
2082                         printk(KERN_ERR "EXT4-fs: %s: Filesystem with huge "
2083                                         "files cannot be mounted read-write "
2084                                         "without CONFIG_LSF.\n", sb->s_id);
2085                         goto failed_mount;
2086                 }
2087         }
2088         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2089
2090         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2091             blocksize > EXT4_MAX_BLOCK_SIZE) {
2092                 printk(KERN_ERR
2093                        "EXT4-fs: Unsupported filesystem blocksize %d on %s.\n",
2094                        blocksize, sb->s_id);
2095                 goto failed_mount;
2096         }
2097
2098         if (sb->s_blocksize != blocksize) {
2099
2100                 /* Validate the filesystem blocksize */
2101                 if (!sb_set_blocksize(sb, blocksize)) {
2102                         printk(KERN_ERR "EXT4-fs: bad block size %d.\n",
2103                                         blocksize);
2104                         goto failed_mount;
2105                 }
2106
2107                 brelse(bh);
2108                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2109                 offset = do_div(logical_sb_block, blocksize);
2110                 bh = sb_bread(sb, logical_sb_block);
2111                 if (!bh) {
2112                         printk(KERN_ERR
2113                                "EXT4-fs: Can't read superblock on 2nd try.\n");
2114                         goto failed_mount;
2115                 }
2116                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2117                 sbi->s_es = es;
2118                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2119                         printk(KERN_ERR
2120                                "EXT4-fs: Magic mismatch, very weird !\n");
2121                         goto failed_mount;
2122                 }
2123         }
2124
2125         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits);
2126         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits);
2127
2128         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2129                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2130                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2131         } else {
2132                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2133                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2134                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2135                     (!is_power_of_2(sbi->s_inode_size)) ||
2136                     (sbi->s_inode_size > blocksize)) {
2137                         printk(KERN_ERR
2138                                "EXT4-fs: unsupported inode size: %d\n",
2139                                sbi->s_inode_size);
2140                         goto failed_mount;
2141                 }
2142                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2143                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2144         }
2145         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2146         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2147                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2148                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2149                     !is_power_of_2(sbi->s_desc_size)) {
2150                         printk(KERN_ERR
2151                                "EXT4-fs: unsupported descriptor size %lu\n",
2152                                sbi->s_desc_size);
2153                         goto failed_mount;
2154                 }
2155         } else
2156                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2157         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2158         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2159         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2160                 goto cantfind_ext4;
2161         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2162         if (sbi->s_inodes_per_block == 0)
2163                 goto cantfind_ext4;
2164         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2165                                         sbi->s_inodes_per_block;
2166         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2167         sbi->s_sbh = bh;
2168         sbi->s_mount_state = le16_to_cpu(es->s_state);
2169         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2170         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2171         for (i = 0; i < 4; i++)
2172                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2173         sbi->s_def_hash_version = es->s_def_hash_version;
2174
2175         if (sbi->s_blocks_per_group > blocksize * 8) {
2176                 printk(KERN_ERR
2177                        "EXT4-fs: #blocks per group too big: %lu\n",
2178                        sbi->s_blocks_per_group);
2179                 goto failed_mount;
2180         }
2181         if (sbi->s_inodes_per_group > blocksize * 8) {
2182                 printk(KERN_ERR
2183                        "EXT4-fs: #inodes per group too big: %lu\n",
2184                        sbi->s_inodes_per_group);
2185                 goto failed_mount;
2186         }
2187
2188         if (ext4_blocks_count(es) >
2189                     (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
2190                 printk(KERN_ERR "EXT4-fs: filesystem on %s:"
2191                         " too large to mount safely\n", sb->s_id);
2192                 if (sizeof(sector_t) < 8)
2193                         printk(KERN_WARNING "EXT4-fs: CONFIG_LBD not "
2194                                         "enabled\n");
2195                 goto failed_mount;
2196         }
2197
2198         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2199                 goto cantfind_ext4;
2200
2201         /* ensure blocks_count calculation below doesn't sign-extend */
2202         if (ext4_blocks_count(es) + EXT4_BLOCKS_PER_GROUP(sb) <
2203             le32_to_cpu(es->s_first_data_block) + 1) {
2204                 printk(KERN_WARNING "EXT4-fs: bad geometry: block count %llu, "
2205                        "first data block %u, blocks per group %lu\n",
2206                         ext4_blocks_count(es),
2207                         le32_to_cpu(es->s_first_data_block),
2208                         EXT4_BLOCKS_PER_GROUP(sb));
2209                 goto failed_mount;
2210         }
2211         blocks_count = (ext4_blocks_count(es) -
2212                         le32_to_cpu(es->s_first_data_block) +
2213                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2214         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2215         sbi->s_groups_count = blocks_count;
2216         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2217                    EXT4_DESC_PER_BLOCK(sb);
2218         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2219                                     GFP_KERNEL);
2220         if (sbi->s_group_desc == NULL) {
2221                 printk(KERN_ERR "EXT4-fs: not enough memory\n");
2222                 goto failed_mount;
2223         }
2224
2225         bgl_lock_init(&sbi->s_blockgroup_lock);
2226
2227         for (i = 0; i < db_count; i++) {
2228                 block = descriptor_loc(sb, logical_sb_block, i);
2229                 sbi->s_group_desc[i] = sb_bread(sb, block);
2230                 if (!sbi->s_group_desc[i]) {
2231                         printk(KERN_ERR "EXT4-fs: "
2232                                "can't read group descriptor %d\n", i);
2233                         db_count = i;
2234                         goto failed_mount2;
2235                 }
2236         }
2237         if (!ext4_check_descriptors(sb)) {
2238                 printk(KERN_ERR "EXT4-fs: group descriptors corrupted!\n");
2239                 goto failed_mount2;
2240         }
2241         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2242                 if (!ext4_fill_flex_info(sb)) {
2243                         printk(KERN_ERR
2244                                "EXT4-fs: unable to initialize "
2245                                "flex_bg meta info!\n");
2246                         goto failed_mount2;
2247                 }
2248
2249         sbi->s_gdb_count = db_count;
2250         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2251         spin_lock_init(&sbi->s_next_gen_lock);
2252
2253         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2254                         ext4_count_free_blocks(sb));
2255         if (!err) {
2256                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2257                                 ext4_count_free_inodes(sb));
2258         }
2259         if (!err) {
2260                 err = percpu_counter_init(&sbi->s_dirs_counter,
2261                                 ext4_count_dirs(sb));
2262         }
2263         if (!err) {
2264                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2265         }
2266         if (err) {
2267                 printk(KERN_ERR "EXT4-fs: insufficient memory\n");
2268                 goto failed_mount3;
2269         }
2270
2271         /* per fileystem reservation list head & lock */
2272         spin_lock_init(&sbi->s_rsv_window_lock);
2273         sbi->s_rsv_window_root = RB_ROOT;
2274         /* Add a single, static dummy reservation to the start of the
2275          * reservation window list --- it gives us a placeholder for
2276          * append-at-start-of-list which makes the allocation logic
2277          * _much_ simpler. */
2278         sbi->s_rsv_window_head.rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
2279         sbi->s_rsv_window_head.rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
2280         sbi->s_rsv_window_head.rsv_alloc_hit = 0;
2281         sbi->s_rsv_window_head.rsv_goal_size = 0;
2282         ext4_rsv_window_add(sb, &sbi->s_rsv_window_head);
2283
2284         sbi->s_stripe = ext4_get_stripe_size(sbi);
2285
2286         /*
2287          * set up enough so that it can read an inode
2288          */
2289         sb->s_op = &ext4_sops;
2290         sb->s_export_op = &ext4_export_ops;
2291         sb->s_xattr = ext4_xattr_handlers;
2292 #ifdef CONFIG_QUOTA
2293         sb->s_qcop = &ext4_qctl_operations;
2294         sb->dq_op = &ext4_quota_operations;
2295 #endif
2296         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2297
2298         sb->s_root = NULL;
2299
2300         needs_recovery = (es->s_last_orphan != 0 ||
2301                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2302                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2303
2304         /*
2305          * The first inode we look at is the journal inode.  Don't try
2306          * root first: it may be modified in the journal!
2307          */
2308         if (!test_opt(sb, NOLOAD) &&
2309             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2310                 if (ext4_load_journal(sb, es, journal_devnum))
2311                         goto failed_mount3;
2312                 if (!(sb->s_flags & MS_RDONLY) &&
2313                     EXT4_SB(sb)->s_journal->j_failed_commit) {
2314                         printk(KERN_CRIT "EXT4-fs error (device %s): "
2315                                "ext4_fill_super: Journal transaction "
2316                                "%u is corrupt\n", sb->s_id,
2317                                EXT4_SB(sb)->s_journal->j_failed_commit);
2318                         if (test_opt(sb, ERRORS_RO)) {
2319                                 printk(KERN_CRIT
2320                                        "Mounting filesystem read-only\n");
2321                                 sb->s_flags |= MS_RDONLY;
2322                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2323                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2324                         }
2325                         if (test_opt(sb, ERRORS_PANIC)) {
2326                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2327                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2328                                 ext4_commit_super(sb, es, 1);
2329                                 printk(KERN_CRIT
2330                                        "EXT4-fs (device %s): mount failed\n",
2331                                       sb->s_id);
2332                                 goto failed_mount4;
2333                         }
2334                 }
2335         } else if (journal_inum) {
2336                 if (ext4_create_journal(sb, es, journal_inum))
2337                         goto failed_mount3;
2338         } else {
2339                 if (!silent)
2340                         printk(KERN_ERR
2341                                "ext4: No journal on filesystem on %s\n",
2342                                sb->s_id);
2343                 goto failed_mount3;
2344         }
2345
2346         if (ext4_blocks_count(es) > 0xffffffffULL &&
2347             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2348                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2349                 printk(KERN_ERR "ext4: Failed to set 64-bit journal feature\n");
2350                 goto failed_mount4;
2351         }
2352
2353         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2354                 jbd2_journal_set_features(sbi->s_journal,
2355                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2356                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2357         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2358                 jbd2_journal_set_features(sbi->s_journal,
2359                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2360                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2361                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2362         } else {
2363                 jbd2_journal_clear_features(sbi->s_journal,
2364                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2365                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2366         }
2367
2368         /* We have now updated the journal if required, so we can
2369          * validate the data journaling mode. */
2370         switch (test_opt(sb, DATA_FLAGS)) {
2371         case 0:
2372                 /* No mode set, assume a default based on the journal
2373                  * capabilities: ORDERED_DATA if the journal can
2374                  * cope, else JOURNAL_DATA
2375                  */
2376                 if (jbd2_journal_check_available_features
2377                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2378                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2379                 else
2380                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2381                 break;
2382
2383         case EXT4_MOUNT_ORDERED_DATA:
2384         case EXT4_MOUNT_WRITEBACK_DATA:
2385                 if (!jbd2_journal_check_available_features
2386                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2387                         printk(KERN_ERR "EXT4-fs: Journal does not support "
2388                                "requested data journaling mode\n");
2389                         goto failed_mount4;
2390                 }
2391         default:
2392                 break;
2393         }
2394
2395         if (test_opt(sb, NOBH)) {
2396                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2397                         printk(KERN_WARNING "EXT4-fs: Ignoring nobh option - "
2398                                 "its supported only with writeback mode\n");
2399                         clear_opt(sbi->s_mount_opt, NOBH);
2400                 }
2401         }
2402         /*
2403          * The jbd2_journal_load will have done any necessary log recovery,
2404          * so we can safely mount the rest of the filesystem now.
2405          */
2406
2407         root = ext4_iget(sb, EXT4_ROOT_INO);
2408         if (IS_ERR(root)) {
2409                 printk(KERN_ERR "EXT4-fs: get root inode failed\n");
2410                 ret = PTR_ERR(root);
2411                 goto failed_mount4;
2412         }
2413         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2414                 iput(root);
2415                 printk(KERN_ERR "EXT4-fs: corrupt root inode, run e2fsck\n");
2416                 goto failed_mount4;
2417         }
2418         sb->s_root = d_alloc_root(root);
2419         if (!sb->s_root) {
2420                 printk(KERN_ERR "EXT4-fs: get root dentry failed\n");
2421                 iput(root);
2422                 ret = -ENOMEM;
2423                 goto failed_mount4;
2424         }
2425
2426         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2427
2428         /* determine the minimum size of new large inodes, if present */
2429         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2430                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2431                                                      EXT4_GOOD_OLD_INODE_SIZE;
2432                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2433                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2434                         if (sbi->s_want_extra_isize <
2435                             le16_to_cpu(es->s_want_extra_isize))
2436                                 sbi->s_want_extra_isize =
2437                                         le16_to_cpu(es->s_want_extra_isize);
2438                         if (sbi->s_want_extra_isize <
2439                             le16_to_cpu(es->s_min_extra_isize))
2440                                 sbi->s_want_extra_isize =
2441                                         le16_to_cpu(es->s_min_extra_isize);
2442                 }
2443         }
2444         /* Check if enough inode space is available */
2445         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2446                                                         sbi->s_inode_size) {
2447                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2448                                                        EXT4_GOOD_OLD_INODE_SIZE;
2449                 printk(KERN_INFO "EXT4-fs: required extra inode space not"
2450                         "available.\n");
2451         }
2452
2453         /*
2454          * akpm: core read_super() calls in here with the superblock locked.
2455          * That deadlocks, because orphan cleanup needs to lock the superblock
2456          * in numerous places.  Here we just pop the lock - it's relatively
2457          * harmless, because we are now ready to accept write_super() requests,
2458          * and aviro says that's the only reason for hanging onto the
2459          * superblock lock.
2460          */
2461         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2462         ext4_orphan_cleanup(sb, es);
2463         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2464         if (needs_recovery)
2465                 printk(KERN_INFO "EXT4-fs: recovery complete.\n");
2466         ext4_mark_recovery_complete(sb, es);
2467         printk(KERN_INFO "EXT4-fs: mounted filesystem with %s data mode.\n",
2468                test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ? "journal":
2469                test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA ? "ordered":
2470                "writeback");
2471
2472         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
2473                 printk(KERN_WARNING "EXT4-fs: Ignoring delalloc option - "
2474                                 "requested data journaling mode\n");
2475                 clear_opt(sbi->s_mount_opt, DELALLOC);
2476         } else if (test_opt(sb, DELALLOC))
2477                 printk(KERN_INFO "EXT4-fs: delayed allocation enabled\n");
2478
2479         ext4_ext_init(sb);
2480         ext4_mb_init(sb, needs_recovery);
2481
2482         lock_kernel();
2483         return 0;
2484
2485 cantfind_ext4:
2486         if (!silent)
2487                 printk(KERN_ERR "VFS: Can't find ext4 filesystem on dev %s.\n",
2488                        sb->s_id);
2489         goto failed_mount;
2490
2491 failed_mount4:
2492         jbd2_journal_destroy(sbi->s_journal);
2493         sbi->s_journal = NULL;
2494 failed_mount3:
2495         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2496         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2497         percpu_counter_destroy(&sbi->s_dirs_counter);
2498         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2499 failed_mount2:
2500         for (i = 0; i < db_count; i++)
2501                 brelse(sbi->s_group_desc[i]);
2502         kfree(sbi->s_group_desc);
2503 failed_mount:
2504 #ifdef CONFIG_QUOTA
2505         for (i = 0; i < MAXQUOTAS; i++)
2506                 kfree(sbi->s_qf_names[i]);
2507 #endif
2508         ext4_blkdev_remove(sbi);
2509         brelse(bh);
2510 out_fail:
2511         sb->s_fs_info = NULL;
2512         kfree(sbi);
2513         lock_kernel();
2514         return ret;
2515 }
2516
2517 /*
2518  * Setup any per-fs journal parameters now.  We'll do this both on
2519  * initial mount, once the journal has been initialised but before we've
2520  * done any recovery; and again on any subsequent remount.
2521  */
2522 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2523 {
2524         struct ext4_sb_info *sbi = EXT4_SB(sb);
2525
2526         if (sbi->s_commit_interval)
2527                 journal->j_commit_interval = sbi->s_commit_interval;
2528         /* We could also set up an ext4-specific default for the commit
2529          * interval here, but for now we'll just fall back to the jbd
2530          * default. */
2531
2532         spin_lock(&journal->j_state_lock);
2533         if (test_opt(sb, BARRIER))
2534                 journal->j_flags |= JBD2_BARRIER;
2535         else
2536                 journal->j_flags &= ~JBD2_BARRIER;
2537         spin_unlock(&journal->j_state_lock);
2538 }
2539
2540 static journal_t *ext4_get_journal(struct super_block *sb,
2541                                    unsigned int journal_inum)
2542 {
2543         struct inode *journal_inode;
2544         journal_t *journal;
2545
2546         /* First, test for the existence of a valid inode on disk.  Bad
2547          * things happen if we iget() an unused inode, as the subsequent
2548          * iput() will try to delete it. */
2549
2550         journal_inode = ext4_iget(sb, journal_inum);
2551         if (IS_ERR(journal_inode)) {
2552                 printk(KERN_ERR "EXT4-fs: no journal found.\n");
2553                 return NULL;
2554         }
2555         if (!journal_inode->i_nlink) {
2556                 make_bad_inode(journal_inode);
2557                 iput(journal_inode);
2558                 printk(KERN_ERR "EXT4-fs: journal inode is deleted.\n");
2559                 return NULL;
2560         }
2561
2562         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
2563                   journal_inode, journal_inode->i_size);
2564         if (!S_ISREG(journal_inode->i_mode)) {
2565                 printk(KERN_ERR "EXT4-fs: invalid journal inode.\n");
2566                 iput(journal_inode);
2567                 return NULL;
2568         }
2569
2570         journal = jbd2_journal_init_inode(journal_inode);
2571         if (!journal) {
2572                 printk(KERN_ERR "EXT4-fs: Could not load journal inode\n");
2573                 iput(journal_inode);
2574                 return NULL;
2575         }
2576         journal->j_private = sb;
2577         ext4_init_journal_params(sb, journal);
2578         return journal;
2579 }
2580
2581 static journal_t *ext4_get_dev_journal(struct super_block *sb,
2582                                        dev_t j_dev)
2583 {
2584         struct buffer_head *bh;
2585         journal_t *journal;
2586         ext4_fsblk_t start;
2587         ext4_fsblk_t len;
2588         int hblock, blocksize;
2589         ext4_fsblk_t sb_block;
2590         unsigned long offset;
2591         struct ext4_super_block *es;
2592         struct block_device *bdev;
2593
2594         bdev = ext4_blkdev_get(j_dev);
2595         if (bdev == NULL)
2596                 return NULL;
2597
2598         if (bd_claim(bdev, sb)) {
2599                 printk(KERN_ERR
2600                         "EXT4: failed to claim external journal device.\n");
2601                 blkdev_put(bdev);
2602                 return NULL;
2603         }
2604
2605         blocksize = sb->s_blocksize;
2606         hblock = bdev_hardsect_size(bdev);
2607         if (blocksize < hblock) {
2608                 printk(KERN_ERR
2609                         "EXT4-fs: blocksize too small for journal device.\n");
2610                 goto out_bdev;
2611         }
2612
2613         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
2614         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
2615         set_blocksize(bdev, blocksize);
2616         if (!(bh = __bread(bdev, sb_block, blocksize))) {
2617                 printk(KERN_ERR "EXT4-fs: couldn't read superblock of "
2618                        "external journal\n");
2619                 goto out_bdev;
2620         }
2621
2622         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2623         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
2624             !(le32_to_cpu(es->s_feature_incompat) &
2625               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
2626                 printk(KERN_ERR "EXT4-fs: external journal has "
2627                                         "bad superblock\n");
2628                 brelse(bh);
2629                 goto out_bdev;
2630         }
2631
2632         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
2633                 printk(KERN_ERR "EXT4-fs: journal UUID does not match\n");
2634                 brelse(bh);
2635                 goto out_bdev;
2636         }
2637
2638         len = ext4_blocks_count(es);
2639         start = sb_block + 1;
2640         brelse(bh);     /* we're done with the superblock */
2641
2642         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
2643                                         start, len, blocksize);
2644         if (!journal) {
2645                 printk(KERN_ERR "EXT4-fs: failed to create device journal\n");
2646                 goto out_bdev;
2647         }
2648         journal->j_private = sb;
2649         ll_rw_block(READ, 1, &journal->j_sb_buffer);
2650         wait_on_buffer(journal->j_sb_buffer);
2651         if (!buffer_uptodate(journal->j_sb_buffer)) {
2652                 printk(KERN_ERR "EXT4-fs: I/O error on journal device\n");
2653                 goto out_journal;
2654         }
2655         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
2656                 printk(KERN_ERR "EXT4-fs: External journal has more than one "
2657                                         "user (unsupported) - %d\n",
2658                         be32_to_cpu(journal->j_superblock->s_nr_users));
2659                 goto out_journal;
2660         }
2661         EXT4_SB(sb)->journal_bdev = bdev;
2662         ext4_init_journal_params(sb, journal);
2663         return journal;
2664 out_journal:
2665         jbd2_journal_destroy(journal);
2666 out_bdev:
2667         ext4_blkdev_put(bdev);
2668         return NULL;
2669 }
2670
2671 static int ext4_load_journal(struct super_block *sb,
2672                              struct ext4_super_block *es,
2673                              unsigned long journal_devnum)
2674 {
2675         journal_t *journal;
2676         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
2677         dev_t journal_dev;
2678         int err = 0;
2679         int really_read_only;
2680
2681         if (journal_devnum &&
2682             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2683                 printk(KERN_INFO "EXT4-fs: external journal device major/minor "
2684                         "numbers have changed\n");
2685                 journal_dev = new_decode_dev(journal_devnum);
2686         } else
2687                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
2688
2689         really_read_only = bdev_read_only(sb->s_bdev);
2690
2691         /*
2692          * Are we loading a blank journal or performing recovery after a
2693          * crash?  For recovery, we need to check in advance whether we
2694          * can get read-write access to the device.
2695          */
2696
2697         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2698                 if (sb->s_flags & MS_RDONLY) {
2699                         printk(KERN_INFO "EXT4-fs: INFO: recovery "
2700                                         "required on readonly filesystem.\n");
2701                         if (really_read_only) {
2702                                 printk(KERN_ERR "EXT4-fs: write access "
2703                                         "unavailable, cannot proceed.\n");
2704                                 return -EROFS;
2705                         }
2706                         printk(KERN_INFO "EXT4-fs: write access will "
2707                                "be enabled during recovery.\n");
2708                 }
2709         }
2710
2711         if (journal_inum && journal_dev) {
2712                 printk(KERN_ERR "EXT4-fs: filesystem has both journal "
2713                        "and inode journals!\n");
2714                 return -EINVAL;
2715         }
2716
2717         if (journal_inum) {
2718                 if (!(journal = ext4_get_journal(sb, journal_inum)))
2719                         return -EINVAL;
2720         } else {
2721                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
2722                         return -EINVAL;
2723         }
2724
2725         if (journal->j_flags & JBD2_BARRIER)
2726                 printk(KERN_INFO "EXT4-fs: barriers enabled\n");
2727         else
2728                 printk(KERN_INFO "EXT4-fs: barriers disabled\n");
2729
2730         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
2731                 err = jbd2_journal_update_format(journal);
2732                 if (err)  {
2733                         printk(KERN_ERR "EXT4-fs: error updating journal.\n");
2734                         jbd2_journal_destroy(journal);
2735                         return err;
2736                 }
2737         }
2738
2739         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
2740                 err = jbd2_journal_wipe(journal, !really_read_only);
2741         if (!err)
2742                 err = jbd2_journal_load(journal);
2743
2744         if (err) {
2745                 printk(KERN_ERR "EXT4-fs: error loading journal.\n");
2746                 jbd2_journal_destroy(journal);
2747                 return err;
2748         }
2749
2750         EXT4_SB(sb)->s_journal = journal;
2751         ext4_clear_journal_err(sb, es);
2752
2753         if (journal_devnum &&
2754             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
2755                 es->s_journal_dev = cpu_to_le32(journal_devnum);
2756                 sb->s_dirt = 1;
2757
2758                 /* Make sure we flush the recovery flag to disk. */
2759                 ext4_commit_super(sb, es, 1);
2760         }
2761
2762         return 0;
2763 }
2764
2765 static int ext4_create_journal(struct super_block *sb,
2766                                struct ext4_super_block *es,
2767                                unsigned int journal_inum)
2768 {
2769         journal_t *journal;
2770         int err;
2771
2772         if (sb->s_flags & MS_RDONLY) {
2773                 printk(KERN_ERR "EXT4-fs: readonly filesystem when trying to "
2774                                 "create journal.\n");
2775                 return -EROFS;
2776         }
2777
2778         journal = ext4_get_journal(sb, journal_inum);
2779         if (!journal)
2780                 return -EINVAL;
2781
2782         printk(KERN_INFO "EXT4-fs: creating new journal on inode %u\n",
2783                journal_inum);
2784
2785         err = jbd2_journal_create(journal);
2786         if (err) {
2787                 printk(KERN_ERR "EXT4-fs: error creating journal.\n");
2788                 jbd2_journal_destroy(journal);
2789                 return -EIO;
2790         }
2791
2792         EXT4_SB(sb)->s_journal = journal;
2793
2794         ext4_update_dynamic_rev(sb);
2795         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2796         EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL);
2797
2798         es->s_journal_inum = cpu_to_le32(journal_inum);
2799         sb->s_dirt = 1;
2800
2801         /* Make sure we flush the recovery flag to disk. */
2802         ext4_commit_super(sb, es, 1);
2803
2804         return 0;
2805 }
2806
2807 static void ext4_commit_super(struct super_block *sb,
2808                               struct ext4_super_block *es, int sync)
2809 {
2810         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
2811
2812         if (!sbh)
2813                 return;
2814         es->s_wtime = cpu_to_le32(get_seconds());
2815         ext4_free_blocks_count_set(es, ext4_count_free_blocks(sb));
2816         es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
2817         BUFFER_TRACE(sbh, "marking dirty");
2818         mark_buffer_dirty(sbh);
2819         if (sync)
2820                 sync_dirty_buffer(sbh);
2821 }
2822
2823
2824 /*
2825  * Have we just finished recovery?  If so, and if we are mounting (or
2826  * remounting) the filesystem readonly, then we will end up with a
2827  * consistent fs on disk.  Record that fact.
2828  */
2829 static void ext4_mark_recovery_complete(struct super_block *sb,
2830                                         struct ext4_super_block *es)
2831 {
2832         journal_t *journal = EXT4_SB(sb)->s_journal;
2833
2834         jbd2_journal_lock_updates(journal);
2835         jbd2_journal_flush(journal);
2836         lock_super(sb);
2837         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
2838             sb->s_flags & MS_RDONLY) {
2839                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2840                 sb->s_dirt = 0;
2841                 ext4_commit_super(sb, es, 1);
2842         }
2843         unlock_super(sb);
2844         jbd2_journal_unlock_updates(journal);
2845 }
2846
2847 /*
2848  * If we are mounting (or read-write remounting) a filesystem whose journal
2849  * has recorded an error from a previous lifetime, move that error to the
2850  * main filesystem now.
2851  */
2852 static void ext4_clear_journal_err(struct super_block *sb,
2853                                    struct ext4_super_block *es)
2854 {
2855         journal_t *journal;
2856         int j_errno;
2857         const char *errstr;
2858
2859         journal = EXT4_SB(sb)->s_journal;
2860
2861         /*
2862          * Now check for any error status which may have been recorded in the
2863          * journal by a prior ext4_error() or ext4_abort()
2864          */
2865
2866         j_errno = jbd2_journal_errno(journal);
2867         if (j_errno) {
2868                 char nbuf[16];
2869
2870                 errstr = ext4_decode_error(sb, j_errno, nbuf);
2871                 ext4_warning(sb, __func__, "Filesystem error recorded "
2872                              "from previous mount: %s", errstr);
2873                 ext4_warning(sb, __func__, "Marking fs in need of "
2874                              "filesystem check.");
2875
2876                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2877                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2878                 ext4_commit_super(sb, es, 1);
2879
2880                 jbd2_journal_clear_err(journal);
2881         }
2882 }
2883
2884 /*
2885  * Force the running and committing transactions to commit,
2886  * and wait on the commit.
2887  */
2888 int ext4_force_commit(struct super_block *sb)
2889 {
2890         journal_t *journal;
2891         int ret;
2892
2893         if (sb->s_flags & MS_RDONLY)
2894                 return 0;
2895
2896         journal = EXT4_SB(sb)->s_journal;
2897         sb->s_dirt = 0;
2898         ret = ext4_journal_force_commit(journal);
2899         return ret;
2900 }
2901
2902 /*
2903  * Ext4 always journals updates to the superblock itself, so we don't
2904  * have to propagate any other updates to the superblock on disk at this
2905  * point.  Just start an async writeback to get the buffers on their way
2906  * to the disk.
2907  *
2908  * This implicitly triggers the writebehind on sync().
2909  */
2910
2911 static void ext4_write_super(struct super_block *sb)
2912 {
2913         if (mutex_trylock(&sb->s_lock) != 0)
2914                 BUG();
2915         sb->s_dirt = 0;
2916 }
2917
2918 static int ext4_sync_fs(struct super_block *sb, int wait)
2919 {
2920         tid_t target;
2921
2922         sb->s_dirt = 0;
2923         if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, &target)) {
2924                 if (wait)
2925                         jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, target);
2926         }
2927         return 0;
2928 }
2929
2930 /*
2931  * LVM calls this function before a (read-only) snapshot is created.  This
2932  * gives us a chance to flush the journal completely and mark the fs clean.
2933  */
2934 static void ext4_write_super_lockfs(struct super_block *sb)
2935 {
2936         sb->s_dirt = 0;
2937
2938         if (!(sb->s_flags & MS_RDONLY)) {
2939                 journal_t *journal = EXT4_SB(sb)->s_journal;
2940
2941                 /* Now we set up the journal barrier. */
2942                 jbd2_journal_lock_updates(journal);
2943                 jbd2_journal_flush(journal);
2944
2945                 /* Journal blocked and flushed, clear needs_recovery flag. */
2946                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2947                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2948         }
2949 }
2950
2951 /*
2952  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
2953  * flag here, even though the filesystem is not technically dirty yet.
2954  */
2955 static void ext4_unlockfs(struct super_block *sb)
2956 {
2957         if (!(sb->s_flags & MS_RDONLY)) {
2958                 lock_super(sb);
2959                 /* Reser the needs_recovery flag before the fs is unlocked. */
2960                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2961                 ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
2962                 unlock_super(sb);
2963                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
2964         }
2965 }
2966
2967 static int ext4_remount(struct super_block *sb, int *flags, char *data)
2968 {
2969         struct ext4_super_block *es;
2970         struct ext4_sb_info *sbi = EXT4_SB(sb);
2971         ext4_fsblk_t n_blocks_count = 0;
2972         unsigned long old_sb_flags;
2973         struct ext4_mount_options old_opts;
2974         ext4_group_t g;
2975         int err;
2976 #ifdef CONFIG_QUOTA
2977         int i;
2978 #endif
2979
2980         /* Store the original options */
2981         old_sb_flags = sb->s_flags;
2982         old_opts.s_mount_opt = sbi->s_mount_opt;
2983         old_opts.s_resuid = sbi->s_resuid;
2984         old_opts.s_resgid = sbi->s_resgid;
2985         old_opts.s_commit_interval = sbi->s_commit_interval;
2986 #ifdef CONFIG_QUOTA
2987         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
2988         for (i = 0; i < MAXQUOTAS; i++)
2989                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
2990 #endif
2991
2992         /*
2993          * Allow the "check" option to be passed as a remount option.
2994          */
2995         if (!parse_options(data, sb, NULL, NULL, &n_blocks_count, 1)) {
2996                 err = -EINVAL;
2997                 goto restore_opts;
2998         }
2999
3000         if (sbi->s_mount_opt & EXT4_MOUNT_ABORT)
3001                 ext4_abort(sb, __func__, "Abort forced by user");
3002
3003         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3004                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
3005
3006         es = sbi->s_es;
3007
3008         ext4_init_journal_params(sb, sbi->s_journal);
3009
3010         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3011                 n_blocks_count > ext4_blocks_count(es)) {
3012                 if (sbi->s_mount_opt & EXT4_MOUNT_ABORT) {
3013                         err = -EROFS;
3014                         goto restore_opts;
3015                 }
3016
3017                 if (*flags & MS_RDONLY) {
3018                         /*
3019                          * First of all, the unconditional stuff we have to do
3020                          * to disable replay of the journal when we next remount
3021                          */
3022                         sb->s_flags |= MS_RDONLY;
3023
3024                         /*
3025                          * OK, test if we are remounting a valid rw partition
3026                          * readonly, and if so set the rdonly flag and then
3027                          * mark the partition as valid again.
3028                          */
3029                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3030                             (sbi->s_mount_state & EXT4_VALID_FS))
3031                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3032
3033                         /*
3034                          * We have to unlock super so that we can wait for
3035                          * transactions.
3036                          */
3037                         unlock_super(sb);
3038                         ext4_mark_recovery_complete(sb, es);
3039                         lock_super(sb);
3040                 } else {
3041                         __le32 ret;
3042                         if ((ret = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3043                                         ~EXT4_FEATURE_RO_COMPAT_SUPP))) {
3044                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3045                                        "remount RDWR because of unsupported "
3046                                        "optional features (%x).\n",
3047                                        sb->s_id, le32_to_cpu(ret));
3048                                 err = -EROFS;
3049                                 goto restore_opts;
3050                         }
3051
3052                         /*
3053                          * Make sure the group descriptor checksums
3054                          * are sane.  If they aren't, refuse to
3055                          * remount r/w.
3056                          */
3057                         for (g = 0; g < sbi->s_groups_count; g++) {
3058                                 struct ext4_group_desc *gdp =
3059                                         ext4_get_group_desc(sb, g, NULL);
3060
3061                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3062                                         printk(KERN_ERR
3063                "EXT4-fs: ext4_remount: "
3064                 "Checksum for group %lu failed (%u!=%u)\n",
3065                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3066                                                le16_to_cpu(gdp->bg_checksum));
3067                                         err = -EINVAL;
3068                                         goto restore_opts;
3069                                 }
3070                         }
3071
3072                         /*
3073                          * If we have an unprocessed orphan list hanging
3074                          * around from a previously readonly bdev mount,
3075                          * require a full umount/remount for now.
3076                          */
3077                         if (es->s_last_orphan) {
3078                                 printk(KERN_WARNING "EXT4-fs: %s: couldn't "
3079                                        "remount RDWR because of unprocessed "
3080                                        "orphan inode list.  Please "
3081                                        "umount/remount instead.\n",
3082                                        sb->s_id);
3083                                 err = -EINVAL;
3084                                 goto restore_opts;
3085                         }
3086
3087                         /*
3088                          * Mounting a RDONLY partition read-write, so reread
3089                          * and store the current valid flag.  (It may have
3090                          * been changed by e2fsck since we originally mounted
3091                          * the partition.)
3092                          */
3093                         ext4_clear_journal_err(sb, es);
3094                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3095                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3096                                 goto restore_opts;
3097                         if (!ext4_setup_super(sb, es, 0))
3098                                 sb->s_flags &= ~MS_RDONLY;
3099                 }
3100         }
3101 #ifdef CONFIG_QUOTA
3102         /* Release old quota file names */
3103         for (i = 0; i < MAXQUOTAS; i++)
3104                 if (old_opts.s_qf_names[i] &&
3105                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3106                         kfree(old_opts.s_qf_names[i]);
3107 #endif
3108         return 0;
3109 restore_opts:
3110         sb->s_flags = old_sb_flags;
3111         sbi->s_mount_opt = old_opts.s_mount_opt;
3112         sbi->s_resuid = old_opts.s_resuid;
3113         sbi->s_resgid = old_opts.s_resgid;
3114         sbi->s_commit_interval = old_opts.s_commit_interval;
3115 #ifdef CONFIG_QUOTA
3116         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3117         for (i = 0; i < MAXQUOTAS; i++) {
3118                 if (sbi->s_qf_names[i] &&
3119                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3120                         kfree(sbi->s_qf_names[i]);
3121                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3122         }
3123 #endif
3124         return err;
3125 }
3126
3127 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3128 {
3129         struct super_block *sb = dentry->d_sb;
3130         struct ext4_sb_info *sbi = EXT4_SB(sb);
3131         struct ext4_super_block *es = sbi->s_es;
3132         u64 fsid;
3133
3134         if (test_opt(sb, MINIX_DF)) {
3135                 sbi->s_overhead_last = 0;
3136         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3137                 ext4_group_t ngroups = sbi->s_groups_count, i;
3138                 ext4_fsblk_t overhead = 0;
3139                 smp_rmb();
3140
3141                 /*
3142                  * Compute the overhead (FS structures).  This is constant
3143                  * for a given filesystem unless the number of block groups
3144                  * changes so we cache the previous value until it does.
3145                  */
3146
3147                 /*
3148                  * All of the blocks before first_data_block are
3149                  * overhead
3150                  */
3151                 overhead = le32_to_cpu(es->s_first_data_block);
3152
3153                 /*
3154                  * Add the overhead attributed to the superblock and
3155                  * block group descriptors.  If the sparse superblocks
3156                  * feature is turned on, then not all groups have this.
3157                  */
3158                 for (i = 0; i < ngroups; i++) {
3159                         overhead += ext4_bg_has_super(sb, i) +
3160                                 ext4_bg_num_gdb(sb, i);
3161                         cond_resched();
3162                 }
3163
3164                 /*
3165                  * Every block group has an inode bitmap, a block
3166                  * bitmap, and an inode table.
3167                  */
3168                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3169                 sbi->s_overhead_last = overhead;
3170                 smp_wmb();
3171                 sbi->s_blocks_last = ext4_blocks_count(es);
3172         }
3173
3174         buf->f_type = EXT4_SUPER_MAGIC;
3175         buf->f_bsize = sb->s_blocksize;
3176         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3177         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3178                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3179         ext4_free_blocks_count_set(es, buf->f_bfree);
3180         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3181         if (buf->f_bfree < ext4_r_blocks_count(es))
3182                 buf->f_bavail = 0;
3183         buf->f_files = le32_to_cpu(es->s_inodes_count);
3184         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3185         es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
3186         buf->f_namelen = EXT4_NAME_LEN;
3187         fsid = le64_to_cpup((void *)es->s_uuid) ^
3188                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3189         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3190         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3191         return 0;
3192 }
3193
3194 /* Helper function for writing quotas on sync - we need to start transaction before quota file
3195  * is locked for write. Otherwise the are possible deadlocks:
3196  * Process 1                         Process 2
3197  * ext4_create()                     quota_sync()
3198  *   jbd2_journal_start()                   write_dquot()
3199  *   DQUOT_INIT()                        down(dqio_mutex)
3200  *     down(dqio_mutex)                    jbd2_journal_start()
3201  *
3202  */
3203
3204 #ifdef CONFIG_QUOTA
3205
3206 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3207 {
3208         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3209 }
3210
3211 static int ext4_dquot_initialize(struct inode *inode, int type)
3212 {
3213         handle_t *handle;
3214         int ret, err;
3215
3216         /* We may create quota structure so we need to reserve enough blocks */
3217         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_INIT_BLOCKS(inode->i_sb));
3218         if (IS_ERR(handle))
3219                 return PTR_ERR(handle);
3220         ret = dquot_initialize(inode, type);
3221         err = ext4_journal_stop(handle);
3222         if (!ret)
3223                 ret = err;
3224         return ret;
3225 }
3226
3227 static int ext4_dquot_drop(struct inode *inode)
3228 {
3229         handle_t *handle;
3230         int ret, err;
3231
3232         /* We may delete quota structure so we need to reserve enough blocks */
3233         handle = ext4_journal_start(inode, 2*EXT4_QUOTA_DEL_BLOCKS(inode->i_sb));
3234         if (IS_ERR(handle)) {
3235                 /*
3236                  * We call dquot_drop() anyway to at least release references
3237                  * to quota structures so that umount does not hang.
3238                  */
3239                 dquot_drop(inode);
3240                 return PTR_ERR(handle);
3241         }
3242         ret = dquot_drop(inode);
3243         err = ext4_journal_stop(handle);
3244         if (!ret)
3245                 ret = err;
3246         return ret;
3247 }
3248
3249 static int ext4_write_dquot(struct dquot *dquot)
3250 {
3251         int ret, err;
3252         handle_t *handle;
3253         struct inode *inode;
3254
3255         inode = dquot_to_inode(dquot);
3256         handle = ext4_journal_start(inode,
3257                                         EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3258         if (IS_ERR(handle))
3259                 return PTR_ERR(handle);
3260         ret = dquot_commit(dquot);
3261         err = ext4_journal_stop(handle);
3262         if (!ret)
3263                 ret = err;
3264         return ret;
3265 }
3266
3267 static int ext4_acquire_dquot(struct dquot *dquot)
3268 {
3269         int ret, err;
3270         handle_t *handle;
3271
3272         handle = ext4_journal_start(dquot_to_inode(dquot),
3273                                         EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3274         if (IS_ERR(handle))
3275                 return PTR_ERR(handle);
3276         ret = dquot_acquire(dquot);
3277         err = ext4_journal_stop(handle);
3278         if (!ret)
3279                 ret = err;
3280         return ret;
3281 }
3282
3283 static int ext4_release_dquot(struct dquot *dquot)
3284 {
3285         int ret, err;
3286         handle_t *handle;
3287
3288         handle = ext4_journal_start(dquot_to_inode(dquot),
3289                                         EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3290         if (IS_ERR(handle)) {
3291                 /* Release dquot anyway to avoid endless cycle in dqput() */
3292                 dquot_release(dquot);
3293                 return PTR_ERR(handle);
3294         }
3295         ret = dquot_release(dquot);
3296         err = ext4_journal_stop(handle);
3297         if (!ret)
3298                 ret = err;
3299         return ret;
3300 }
3301
3302 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3303 {
3304         /* Are we journaling quotas? */
3305         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3306             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3307                 dquot_mark_dquot_dirty(dquot);
3308                 return ext4_write_dquot(dquot);
3309         } else {
3310                 return dquot_mark_dquot_dirty(dquot);
3311         }
3312 }
3313
3314 static int ext4_write_info(struct super_block *sb, int type)
3315 {
3316         int ret, err;
3317         handle_t *handle;
3318
3319         /* Data block + inode block */
3320         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3321         if (IS_ERR(handle))
3322                 return PTR_ERR(handle);
3323         ret = dquot_commit_info(sb, type);
3324         err = ext4_journal_stop(handle);
3325         if (!ret)
3326                 ret = err;
3327         return ret;
3328 }
3329
3330 /*
3331  * Turn on quotas during mount time - we need to find
3332  * the quota file and such...
3333  */
3334 static int ext4_quota_on_mount(struct super_block *sb, int type)
3335 {
3336         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3337                         EXT4_SB(sb)->s_jquota_fmt, type);
3338 }
3339
3340 /*
3341  * Standard function to be called on quota_on
3342  */
3343 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3344                          char *path, int remount)
3345 {
3346         int err;
3347         struct nameidata nd;
3348
3349         if (!test_opt(sb, QUOTA))
3350                 return -EINVAL;
3351         /* When remounting, no checks are needed and in fact, path is NULL */
3352         if (remount)
3353                 return vfs_quota_on(sb, type, format_id, path, remount);
3354
3355         err = path_lookup(path, LOOKUP_FOLLOW, &nd);
3356         if (err)
3357                 return err;
3358
3359         /* Quotafile not on the same filesystem? */
3360         if (nd.path.mnt->mnt_sb != sb) {
3361                 path_put(&nd.path);
3362                 return -EXDEV;
3363         }
3364         /* Journaling quota? */
3365         if (EXT4_SB(sb)->s_qf_names[type]) {
3366                 /* Quotafile not in fs root? */
3367                 if (nd.path.dentry->d_parent->d_inode != sb->s_root->d_inode)
3368                         printk(KERN_WARNING
3369                                 "EXT4-fs: Quota file not on filesystem root. "
3370                                 "Journaled quota will not work.\n");
3371         }
3372
3373         /*
3374          * When we journal data on quota file, we have to flush journal to see
3375          * all updates to the file when we bypass pagecache...
3376          */
3377         if (ext4_should_journal_data(nd.path.dentry->d_inode)) {
3378                 /*
3379                  * We don't need to lock updates but journal_flush() could
3380                  * otherwise be livelocked...
3381                  */
3382                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3383                 jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3384                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3385         }
3386
3387         err = vfs_quota_on_path(sb, type, format_id, &nd.path);
3388         path_put(&nd.path);
3389         return err;
3390 }
3391
3392 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3393  * acquiring the locks... As quota files are never truncated and quota code
3394  * itself serializes the operations (and noone else should touch the files)
3395  * we don't have to be afraid of races */
3396 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3397                                size_t len, loff_t off)
3398 {
3399         struct inode *inode = sb_dqopt(sb)->files[type];
3400         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3401         int err = 0;
3402         int offset = off & (sb->s_blocksize - 1);
3403         int tocopy;
3404         size_t toread;
3405         struct buffer_head *bh;
3406         loff_t i_size = i_size_read(inode);
3407
3408         if (off > i_size)
3409                 return 0;
3410         if (off+len > i_size)
3411                 len = i_size-off;
3412         toread = len;
3413         while (toread > 0) {
3414                 tocopy = sb->s_blocksize - offset < toread ?
3415                                 sb->s_blocksize - offset : toread;
3416                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3417                 if (err)
3418                         return err;
3419                 if (!bh)        /* A hole? */
3420                         memset(data, 0, tocopy);
3421                 else
3422                         memcpy(data, bh->b_data+offset, tocopy);
3423                 brelse(bh);
3424                 offset = 0;
3425                 toread -= tocopy;
3426                 data += tocopy;
3427                 blk++;
3428         }
3429         return len;
3430 }
3431
3432 /* Write to quotafile (we know the transaction is already started and has
3433  * enough credits) */
3434 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3435                                 const char *data, size_t len, loff_t off)
3436 {
3437         struct inode *inode = sb_dqopt(sb)->files[type];
3438         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3439         int err = 0;
3440         int offset = off & (sb->s_blocksize - 1);
3441         int tocopy;
3442         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3443         size_t towrite = len;
3444         struct buffer_head *bh;
3445         handle_t *handle = journal_current_handle();
3446
3447         if (!handle) {
3448                 printk(KERN_WARNING "EXT4-fs: Quota write (off=%llu, len=%llu)"
3449                         " cancelled because transaction is not started.\n",
3450                         (unsigned long long)off, (unsigned long long)len);
3451                 return -EIO;
3452         }
3453         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3454         while (towrite > 0) {
3455                 tocopy = sb->s_blocksize - offset < towrite ?
3456                                 sb->s_blocksize - offset : towrite;
3457                 bh = ext4_bread(handle, inode, blk, 1, &err);
3458                 if (!bh)
3459                         goto out;
3460                 if (journal_quota) {
3461                         err = ext4_journal_get_write_access(handle, bh);
3462                         if (err) {
3463                                 brelse(bh);
3464                                 goto out;
3465                         }
3466                 }
3467                 lock_buffer(bh);
3468                 memcpy(bh->b_data+offset, data, tocopy);
3469                 flush_dcache_page(bh->b_page);
3470                 unlock_buffer(bh);
3471                 if (journal_quota)
3472                         err = ext4_journal_dirty_metadata(handle, bh);
3473                 else {
3474                         /* Always do at least ordered writes for quotas */
3475                         err = ext4_jbd2_file_inode(handle, inode);
3476                         mark_buffer_dirty(bh);
3477                 }
3478                 brelse(bh);
3479                 if (err)
3480                         goto out;
3481                 offset = 0;
3482                 towrite -= tocopy;
3483                 data += tocopy;
3484                 blk++;
3485         }
3486 out:
3487         if (len == towrite) {
3488                 mutex_unlock(&inode->i_mutex);
3489                 return err;
3490         }
3491         if (inode->i_size < off+len-towrite) {
3492                 i_size_write(inode, off+len-towrite);
3493                 EXT4_I(inode)->i_disksize = inode->i_size;
3494         }
3495         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3496         ext4_mark_inode_dirty(handle, inode);
3497         mutex_unlock(&inode->i_mutex);
3498         return len - towrite;
3499 }
3500
3501 #endif
3502
3503 static int ext4_get_sb(struct file_system_type *fs_type,
3504         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
3505 {
3506         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
3507 }
3508
3509 static struct file_system_type ext4dev_fs_type = {
3510         .owner          = THIS_MODULE,
3511         .name           = "ext4dev",
3512         .get_sb         = ext4_get_sb,
3513         .kill_sb        = kill_block_super,
3514         .fs_flags       = FS_REQUIRES_DEV,
3515 };
3516
3517 static int __init init_ext4_fs(void)
3518 {
3519         int err;
3520
3521         err = init_ext4_mballoc();
3522         if (err)
3523                 return err;
3524
3525         err = init_ext4_xattr();
3526         if (err)
3527                 goto out2;
3528         err = init_inodecache();
3529         if (err)
3530                 goto out1;
3531         err = register_filesystem(&ext4dev_fs_type);
3532         if (err)
3533                 goto out;
3534         return 0;
3535 out:
3536         destroy_inodecache();
3537 out1:
3538         exit_ext4_xattr();
3539 out2:
3540         exit_ext4_mballoc();
3541         return err;
3542 }
3543
3544 static void __exit exit_ext4_fs(void)
3545 {
3546         unregister_filesystem(&ext4dev_fs_type);
3547         destroy_inodecache();
3548         exit_ext4_xattr();
3549         exit_ext4_mballoc();
3550 }
3551
3552 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
3553 MODULE_DESCRIPTION("Fourth Extended Filesystem with extents");
3554 MODULE_LICENSE("GPL");
3555 module_init(init_ext4_fs)
3556 module_exit(exit_ext4_fs)