fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card ([email protected])
   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 ([email protected]), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/jbd2.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/parser.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/cleancache.h>
  42 #include <asm/uaccess.h>
  43
  44 #include <linux/kthread.h>
  45 #include <linux/freezer.h>
  46
  47 #include "ext4.h"
  48 #include "ext4_extents.h"
  49 #include "ext4_jbd2.h"
  50 #include "xattr.h"
  51 #include "acl.h"
  52 #include "mballoc.h"
  53
  54 #define CREATE_TRACE_POINTS
  55 #include <trace/events/ext4.h>
  56
  57 static struct proc_dir_entry *ext4_proc_root;
  58 static struct kset *ext4_kset;
  59 static struct ext4_lazy_init *ext4_li_info;
  60 static struct mutex ext4_li_mtx;
  61 static struct ext4_features *ext4_feat;
  62
  63 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  64                              unsigned long journal_devnum);
  65 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  66 static int ext4_commit_super(struct super_block *sb, int sync);
  67 static void ext4_mark_recovery_complete(struct super_block *sb,
  68                                         struct ext4_super_block *es);
  69 static void ext4_clear_journal_err(struct super_block *sb,
  70                                    struct ext4_super_block *es);
  71 static int ext4_sync_fs(struct super_block *sb, int wait);
  72 static const char *ext4_decode_error(struct super_block *sb, int errno,
  73                                      char nbuf[16]);
  74 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  75 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  76 static int ext4_unfreeze(struct super_block *sb);
  77 static void ext4_write_super(struct super_block *sb);
  78 static int ext4_freeze(struct super_block *sb);
  79 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  80                        const char *dev_name, void *data);
  81 static inline int ext2_feature_set_ok(struct super_block *sb);
  82 static inline int ext3_feature_set_ok(struct super_block *sb);
  83 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  84 static void ext4_destroy_lazyinit_thread(void);
  85 static void ext4_unregister_li_request(struct super_block *sb);
  86 static void ext4_clear_request_list(void);
  87
  88 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
  89 static struct file_system_type ext2_fs_type = {
  90         .owner          = THIS_MODULE,
  91         .name           = "ext2",
  92         .mount          = ext4_mount,
  93         .kill_sb        = kill_block_super,
  94         .fs_flags       = FS_REQUIRES_DEV,
  95 };
  96 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
  97 #else
  98 #define IS_EXT2_SB(sb) (0)
  99 #endif
 100
 101
 102 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
 103 static struct file_system_type ext3_fs_type = {
 104         .owner          = THIS_MODULE,
 105         .name           = "ext3",
 106         .mount          = ext4_mount,
 107         .kill_sb        = kill_block_super,
 108         .fs_flags       = FS_REQUIRES_DEV,
 109 };
 110 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 111 #else
 112 #define IS_EXT3_SB(sb) (0)
 113 #endif
 114
 115 static int ext4_verify_csum_type(struct super_block *sb,
 116                                  struct ext4_super_block *es)
 117 {
 118         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 119                                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 120                 return 1;
 121
 122         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 123 }
 124
 125 static __le32 ext4_superblock_csum(struct super_block *sb,
 126                                    struct ext4_super_block *es)
 127 {
 128         struct ext4_sb_info *sbi = EXT4_SB(sb);
 129         int offset = offsetof(struct ext4_super_block, s_checksum);
 130         __u32 csum;
 131
 132         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 133
 134         return cpu_to_le32(csum);
 135 }
 136
 137 int ext4_superblock_csum_verify(struct super_block *sb,
 138                                 struct ext4_super_block *es)
 139 {
 140         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 141                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 142                 return 1;
 143
 144         return es->s_checksum == ext4_superblock_csum(sb, es);
 145 }
 146
 147 void ext4_superblock_csum_set(struct super_block *sb,
 148                               struct ext4_super_block *es)
 149 {
 150         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 151                 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 152                 return;
 153
 154         es->s_checksum = ext4_superblock_csum(sb, es);
 155 }
 156
 157 void *ext4_kvmalloc(size_t size, gfp_t flags)
 158 {
 159         void *ret;
 160
 161         ret = kmalloc(size, flags);
 162         if (!ret)
 163                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 164         return ret;
 165 }
 166
 167 void *ext4_kvzalloc(size_t size, gfp_t flags)
 168 {
 169         void *ret;
 170
 171         ret = kzalloc(size, flags);
 172         if (!ret)
 173                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 174         return ret;
 175 }
 176
 177 void ext4_kvfree(void *ptr)
 178 {
 179         if (is_vmalloc_addr(ptr))
 180                 vfree(ptr);
 181         else
 182                 kfree(ptr);
 183
 184 }
 185
 186 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 187                                struct ext4_group_desc *bg)
 188 {
 189         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 190                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 191                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 192 }
 193
 194 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 195                                struct ext4_group_desc *bg)
 196 {
 197         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 198                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 199                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 200 }
 201
 202 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 203                               struct ext4_group_desc *bg)
 204 {
 205         return le32_to_cpu(bg->bg_inode_table_lo) |
 206                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 207                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 208 }
 209
 210 __u32 ext4_free_group_clusters(struct super_block *sb,
 211                                struct ext4_group_desc *bg)
 212 {
 213         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 214                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 215                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 216 }
 217
 218 __u32 ext4_free_inodes_count(struct super_block *sb,
 219                               struct ext4_group_desc *bg)
 220 {
 221         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 222                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 223                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 224 }
 225
 226 __u32 ext4_used_dirs_count(struct super_block *sb,
 227                               struct ext4_group_desc *bg)
 228 {
 229         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 230                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 231                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 232 }
 233
 234 __u32 ext4_itable_unused_count(struct super_block *sb,
 235                               struct ext4_group_desc *bg)
 236 {
 237         return le16_to_cpu(bg->bg_itable_unused_lo) |
 238                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 239                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 240 }
 241
 242 void ext4_block_bitmap_set(struct super_block *sb,
 243                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 244 {
 245         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 246         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 247                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 248 }
 249
 250 void ext4_inode_bitmap_set(struct super_block *sb,
 251                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 252 {
 253         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 254         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 255                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 256 }
 257
 258 void ext4_inode_table_set(struct super_block *sb,
 259                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 260 {
 261         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 262         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 263                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 264 }
 265
 266 void ext4_free_group_clusters_set(struct super_block *sb,
 267                                   struct ext4_group_desc *bg, __u32 count)
 268 {
 269         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 270         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 271                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 272 }
 273
 274 void ext4_free_inodes_set(struct super_block *sb,
 275                           struct ext4_group_desc *bg, __u32 count)
 276 {
 277         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 278         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 279                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 280 }
 281
 282 void ext4_used_dirs_set(struct super_block *sb,
 283                           struct ext4_group_desc *bg, __u32 count)
 284 {
 285         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 286         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 287                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 288 }
 289
 290 void ext4_itable_unused_set(struct super_block *sb,
 291                           struct ext4_group_desc *bg, __u32 count)
 292 {
 293         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 294         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 295                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 296 }
 297
 298
 299 /* Just increment the non-pointer handle value */
 300 static handle_t *ext4_get_nojournal(void)
 301 {
 302         handle_t *handle = current->journal_info;
 303         unsigned long ref_cnt = (unsigned long)handle;
 304
 305         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
 306
 307         ref_cnt++;
 308         handle = (handle_t *)ref_cnt;
 309
 310         current->journal_info = handle;
 311         return handle;
 312 }
 313
 314
 315 /* Decrement the non-pointer handle value */
 316 static void ext4_put_nojournal(handle_t *handle)
 317 {
 318         unsigned long ref_cnt = (unsigned long)handle;
 319
 320         BUG_ON(ref_cnt == 0);
 321
 322         ref_cnt--;
 323         handle = (handle_t *)ref_cnt;
 324
 325         current->journal_info = handle;
 326 }
 327
 328 /*
 329  * Wrappers for jbd2_journal_start/end.
 330  *
 331  * The only special thing we need to do here is to make sure that all
 332  * journal_end calls result in the superblock being marked dirty, so
 333  * that sync() will call the filesystem's write_super callback if
 334  * appropriate.
 335  *
 336  * To avoid j_barrier hold in userspace when a user calls freeze(),
 337  * ext4 prevents a new handle from being started by s_frozen, which
 338  * is in an upper layer.
 339  */
 340 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 341 {
 342         journal_t *journal;
 343         handle_t  *handle;
 344
 345         trace_ext4_journal_start(sb, nblocks, _RET_IP_);
 346         if (sb->s_flags & MS_RDONLY)
 347                 return ERR_PTR(-EROFS);
 348
 349         journal = EXT4_SB(sb)->s_journal;
 350         handle = ext4_journal_current_handle();
 351
 352         /*
 353          * If a handle has been started, it should be allowed to
 354          * finish, otherwise deadlock could happen between freeze
 355          * and others(e.g. truncate) due to the restart of the
 356          * journal handle if the filesystem is forzen and active
 357          * handles are not stopped.
 358          */
 359         if (!handle)
 360                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
 361
 362         if (!journal)
 363                 return ext4_get_nojournal();
 364         /*
 365          * Special case here: if the journal has aborted behind our
 366          * backs (eg. EIO in the commit thread), then we still need to
 367          * take the FS itself readonly cleanly.
 368          */
 369         if (is_journal_aborted(journal)) {
 370                 ext4_abort(sb, "Detected aborted journal");
 371                 return ERR_PTR(-EROFS);
 372         }
 373         return jbd2_journal_start(journal, nblocks);
 374 }
 375
 376 /*
 377  * The only special thing we need to do here is to make sure that all
 378  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 379  * that sync() will call the filesystem's write_super callback if
 380  * appropriate.
 381  */
 382 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
 383 {
 384         struct super_block *sb;
 385         int err;
 386         int rc;
 387
 388         if (!ext4_handle_valid(handle)) {
 389                 ext4_put_nojournal(handle);
 390                 return 0;
 391         }
 392         sb = handle->h_transaction->t_journal->j_private;
 393         err = handle->h_err;
 394         rc = jbd2_journal_stop(handle);
 395
 396         if (!err)
 397                 err = rc;
 398         if (err)
 399                 __ext4_std_error(sb, where, line, err);
 400         return err;
 401 }
 402
 403 void ext4_journal_abort_handle(const char *caller, unsigned int line,
 404                                const char *err_fn, struct buffer_head *bh,
 405                                handle_t *handle, int err)
 406 {
 407         char nbuf[16];
 408         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 409
 410         BUG_ON(!ext4_handle_valid(handle));
 411
 412         if (bh)
 413                 BUFFER_TRACE(bh, "abort");
 414
 415         if (!handle->h_err)
 416                 handle->h_err = err;
 417
 418         if (is_handle_aborted(handle))
 419                 return;
 420
 421         printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n",
 422                caller, line, errstr, err_fn);
 423
 424         jbd2_journal_abort_handle(handle);
 425 }
 426
 427 static void __save_error_info(struct super_block *sb, const char *func,
 428                             unsigned int line)
 429 {
 430         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 431
 432         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 433         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 434         es->s_last_error_time = cpu_to_le32(get_seconds());
 435         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 436         es->s_last_error_line = cpu_to_le32(line);
 437         if (!es->s_first_error_time) {
 438                 es->s_first_error_time = es->s_last_error_time;
 439                 strncpy(es->s_first_error_func, func,
 440                         sizeof(es->s_first_error_func));
 441                 es->s_first_error_line = cpu_to_le32(line);
 442                 es->s_first_error_ino = es->s_last_error_ino;
 443                 es->s_first_error_block = es->s_last_error_block;
 444         }
 445         /*
 446          * Start the daily error reporting function if it hasn't been
 447          * started already
 448          */
 449         if (!es->s_error_count)
 450                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 451         es->s_error_count = cpu_to_le32(le32_to_cpu(es->s_error_count) + 1);
 452 }
 453
 454 static void save_error_info(struct super_block *sb, const char *func,
 455                             unsigned int line)
 456 {
 457         __save_error_info(sb, func, line);
 458         ext4_commit_super(sb, 1);
 459 }
 460
 461 /*
 462  * The del_gendisk() function uninitializes the disk-specific data
 463  * structures, including the bdi structure, without telling anyone
 464  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 465  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 466  * This is a kludge to prevent these oops until we can put in a proper
 467  * hook in del_gendisk() to inform the VFS and file system layers.
 468  */
 469 static int block_device_ejected(struct super_block *sb)
 470 {
 471         struct inode *bd_inode = sb->s_bdev->bd_inode;
 472         struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info;
 473
 474         return bdi->dev == NULL;
 475 }
 476
 477 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 478 {
 479         struct super_block              *sb = journal->j_private;
 480         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 481         int                             error = is_journal_aborted(journal);
 482         struct ext4_journal_cb_entry    *jce, *tmp;
 483
 484         spin_lock(&sbi->s_md_lock);
 485         list_for_each_entry_safe(jce, tmp, &txn->t_private_list, jce_list) {
 486                 list_del_init(&jce->jce_list);
 487                 spin_unlock(&sbi->s_md_lock);
 488                 jce->jce_func(sb, jce, error);
 489                 spin_lock(&sbi->s_md_lock);
 490         }
 491         spin_unlock(&sbi->s_md_lock);
 492 }
 493
 494 /* Deal with the reporting of failure conditions on a filesystem such as
 495  * inconsistencies detected or read IO failures.
 496  *
 497  * On ext2, we can store the error state of the filesystem in the
 498  * superblock.  That is not possible on ext4, because we may have other
 499  * write ordering constraints on the superblock which prevent us from
 500  * writing it out straight away; and given that the journal is about to
 501  * be aborted, we can't rely on the current, or future, transactions to
 502  * write out the superblock safely.
 503  *
 504  * We'll just use the jbd2_journal_abort() error code to record an error in
 505  * the journal instead.  On recovery, the journal will complain about
 506  * that error until we've noted it down and cleared it.
 507  */
 508
 509 static void ext4_handle_error(struct super_block *sb)
 510 {
 511         if (sb->s_flags & MS_RDONLY)
 512                 return;
 513
 514         if (!test_opt(sb, ERRORS_CONT)) {
 515                 journal_t *journal = EXT4_SB(sb)->s_journal;
 516
 517                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 518                 if (journal)
 519                         jbd2_journal_abort(journal, -EIO);
 520         }
 521         if (test_opt(sb, ERRORS_RO)) {
 522                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 523                 sb->s_flags |= MS_RDONLY;
 524         }
 525         if (test_opt(sb, ERRORS_PANIC))
 526                 panic("EXT4-fs (device %s): panic forced after error\n",
 527                         sb->s_id);
 528 }
 529
 530 void __ext4_error(struct super_block *sb, const char *function,
 531                   unsigned int line, const char *fmt, ...)
 532 {
 533         struct va_format vaf;
 534         va_list args;
 535
 536         va_start(args, fmt);
 537         vaf.fmt = fmt;
 538         vaf.va = &args;
 539         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 540                sb->s_id, function, line, current->comm, &vaf);
 541         va_end(args);
 542
 543         ext4_handle_error(sb);
 544 }
 545
 546 void ext4_error_inode(struct inode *inode, const char *function,
 547                       unsigned int line, ext4_fsblk_t block,
 548                       const char *fmt, ...)
 549 {
 550         va_list args;
 551         struct va_format vaf;
 552         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 553
 554         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 555         es->s_last_error_block = cpu_to_le64(block);
 556         save_error_info(inode->i_sb, function, line);
 557         va_start(args, fmt);
 558         vaf.fmt = fmt;
 559         vaf.va = &args;
 560         if (block)
 561                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 562                        "inode #%lu: block %llu: comm %s: %pV\n",
 563                        inode->i_sb->s_id, function, line, inode->i_ino,
 564                        block, current->comm, &vaf);
 565         else
 566                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 567                        "inode #%lu: comm %s: %pV\n",
 568                        inode->i_sb->s_id, function, line, inode->i_ino,
 569                        current->comm, &vaf);
 570         va_end(args);
 571
 572         ext4_handle_error(inode->i_sb);
 573 }
 574
 575 void ext4_error_file(struct file *file, const char *function,
 576                      unsigned int line, ext4_fsblk_t block,
 577                      const char *fmt, ...)
 578 {
 579         va_list args;
 580         struct va_format vaf;
 581         struct ext4_super_block *es;
 582         struct inode *inode = file->f_dentry->d_inode;
 583         char pathname[80], *path;
 584
 585         es = EXT4_SB(inode->i_sb)->s_es;
 586         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 587         save_error_info(inode->i_sb, function, line);
 588         path = d_path(&(file->f_path), pathname, sizeof(pathname));
 589         if (IS_ERR(path))
 590                 path = "(unknown)";
 591         va_start(args, fmt);
 592         vaf.fmt = fmt;
 593         vaf.va = &args;
 594         if (block)
 595                 printk(KERN_CRIT
 596                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 597                        "block %llu: comm %s: path %s: %pV\n",
 598                        inode->i_sb->s_id, function, line, inode->i_ino,
 599                        block, current->comm, path, &vaf);
 600         else
 601                 printk(KERN_CRIT
 602                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 603                        "comm %s: path %s: %pV\n",
 604                        inode->i_sb->s_id, function, line, inode->i_ino,
 605                        current->comm, path, &vaf);
 606         va_end(args);
 607
 608         ext4_handle_error(inode->i_sb);
 609 }
 610
 611 static const char *ext4_decode_error(struct super_block *sb, int errno,
 612                                      char nbuf[16])
 613 {
 614         char *errstr = NULL;
 615
 616         switch (errno) {
 617         case -EIO:
 618                 errstr = "IO failure";
 619                 break;
 620         case -ENOMEM:
 621                 errstr = "Out of memory";
 622                 break;
 623         case -EROFS:
 624                 if (!sb || (EXT4_SB(sb)->s_journal &&
 625                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 626                         errstr = "Journal has aborted";
 627                 else
 628                         errstr = "Readonly filesystem";
 629                 break;
 630         default:
 631                 /* If the caller passed in an extra buffer for unknown
 632                  * errors, textualise them now.  Else we just return
 633                  * NULL. */
 634                 if (nbuf) {
 635                         /* Check for truncated error codes... */
 636                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 637                                 errstr = nbuf;
 638                 }
 639                 break;
 640         }
 641
 642         return errstr;
 643 }
 644
 645 /* __ext4_std_error decodes expected errors from journaling functions
 646  * automatically and invokes the appropriate error response.  */
 647
 648 void __ext4_std_error(struct super_block *sb, const char *function,
 649                       unsigned int line, int errno)
 650 {
 651         char nbuf[16];
 652         const char *errstr;
 653
 654         /* Special case: if the error is EROFS, and we're not already
 655          * inside a transaction, then there's really no point in logging
 656          * an error. */
 657         if (errno == -EROFS && journal_current_handle() == NULL &&
 658             (sb->s_flags & MS_RDONLY))
 659                 return;
 660
 661         errstr = ext4_decode_error(sb, errno, nbuf);
 662         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 663                sb->s_id, function, line, errstr);
 664         save_error_info(sb, function, line);
 665
 666         ext4_handle_error(sb);
 667 }
 668
 669 /*
 670  * ext4_abort is a much stronger failure handler than ext4_error.  The
 671  * abort function may be used to deal with unrecoverable failures such
 672  * as journal IO errors or ENOMEM at a critical moment in log management.
 673  *
 674  * We unconditionally force the filesystem into an ABORT|READONLY state,
 675  * unless the error response on the fs has been set to panic in which
 676  * case we take the easy way out and panic immediately.
 677  */
 678
 679 void __ext4_abort(struct super_block *sb, const char *function,
 680                 unsigned int line, const char *fmt, ...)
 681 {
 682         va_list args;
 683
 684         save_error_info(sb, function, line);
 685         va_start(args, fmt);
 686         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 687                function, line);
 688         vprintk(fmt, args);
 689         printk("\n");
 690         va_end(args);
 691
 692         if ((sb->s_flags & MS_RDONLY) == 0) {
 693                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 694                 sb->s_flags |= MS_RDONLY;
 695                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 696                 if (EXT4_SB(sb)->s_journal)
 697                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 698                 save_error_info(sb, function, line);
 699         }
 700         if (test_opt(sb, ERRORS_PANIC))
 701                 panic("EXT4-fs panic from previous error\n");
 702 }
 703
 704 void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
 705 {
 706         struct va_format vaf;
 707         va_list args;
 708
 709         va_start(args, fmt);
 710         vaf.fmt = fmt;
 711         vaf.va = &args;
 712         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 713         va_end(args);
 714 }
 715
 716 void __ext4_warning(struct super_block *sb, const char *function,
 717                     unsigned int line, const char *fmt, ...)
 718 {
 719         struct va_format vaf;
 720         va_list args;
 721
 722         va_start(args, fmt);
 723         vaf.fmt = fmt;
 724         vaf.va = &args;
 725         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 726                sb->s_id, function, line, &vaf);
 727         va_end(args);
 728 }
 729
 730 void __ext4_grp_locked_error(const char *function, unsigned int line,
 731                              struct super_block *sb, ext4_group_t grp,
 732                              unsigned long ino, ext4_fsblk_t block,
 733                              const char *fmt, ...)
 734 __releases(bitlock)
 735 __acquires(bitlock)
 736 {
 737         struct va_format vaf;
 738         va_list args;
 739         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 740
 741         es->s_last_error_ino = cpu_to_le32(ino);
 742         es->s_last_error_block = cpu_to_le64(block);
 743         __save_error_info(sb, function, line);
 744
 745         va_start(args, fmt);
 746
 747         vaf.fmt = fmt;
 748         vaf.va = &args;
 749         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 750                sb->s_id, function, line, grp);
 751         if (ino)
 752                 printk(KERN_CONT "inode %lu: ", ino);
 753         if (block)
 754                 printk(KERN_CONT "block %llu:", (unsigned long long) block);
 755         printk(KERN_CONT "%pV\n", &vaf);
 756         va_end(args);
 757
 758         if (test_opt(sb, ERRORS_CONT)) {
 759                 ext4_commit_super(sb, 0);
 760                 return;
 761         }
 762
 763         ext4_unlock_group(sb, grp);
 764         ext4_handle_error(sb);
 765         /*
 766          * We only get here in the ERRORS_RO case; relocking the group
 767          * may be dangerous, but nothing bad will happen since the
 768          * filesystem will have already been marked read/only and the
 769          * journal has been aborted.  We return 1 as a hint to callers
 770          * who might what to use the return value from
 771          * ext4_grp_locked_error() to distinguish between the
 772          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 773          * aggressively from the ext4 function in question, with a
 774          * more appropriate error code.
 775          */
 776         ext4_lock_group(sb, grp);
 777         return;
 778 }
 779
 780 void ext4_update_dynamic_rev(struct super_block *sb)
 781 {
 782         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 783
 784         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 785                 return;
 786
 787         ext4_warning(sb,
 788                      "updating to rev %d because of new feature flag, "
 789                      "running e2fsck is recommended",
 790                      EXT4_DYNAMIC_REV);
 791
 792         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 793         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 794         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 795         /* leave es->s_feature_*compat flags alone */
 796         /* es->s_uuid will be set by e2fsck if empty */
 797
 798         /*
 799          * The rest of the superblock fields should be zero, and if not it
 800          * means they are likely already in use, so leave them alone.  We
 801          * can leave it up to e2fsck to clean up any inconsistencies there.
 802          */
 803 }
 804
 805 /*
 806  * Open the external journal device
 807  */
 808 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 809 {
 810         struct block_device *bdev;
 811         char b[BDEVNAME_SIZE];
 812
 813         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 814         if (IS_ERR(bdev))
 815                 goto fail;
 816         return bdev;
 817
 818 fail:
 819         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 820                         __bdevname(dev, b), PTR_ERR(bdev));
 821         return NULL;
 822 }
 823
 824 /*
 825  * Release the journal device
 826  */
 827 static int ext4_blkdev_put(struct block_device *bdev)
 828 {
 829         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 830 }
 831
 832 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 833 {
 834         struct block_device *bdev;
 835         int ret = -ENODEV;
 836
 837         bdev = sbi->journal_bdev;
 838         if (bdev) {
 839                 ret = ext4_blkdev_put(bdev);
 840                 sbi->journal_bdev = NULL;
 841         }
 842         return ret;
 843 }
 844
 845 static inline struct inode *orphan_list_entry(struct list_head *l)
 846 {
 847         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 848 }
 849
 850 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 851 {
 852         struct list_head *l;
 853
 854         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 855                  le32_to_cpu(sbi->s_es->s_last_orphan));
 856
 857         printk(KERN_ERR "sb_info orphan list:\n");
 858         list_for_each(l, &sbi->s_orphan) {
 859                 struct inode *inode = orphan_list_entry(l);
 860                 printk(KERN_ERR "  "
 861                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 862                        inode->i_sb->s_id, inode->i_ino, inode,
 863                        inode->i_mode, inode->i_nlink,
 864                        NEXT_ORPHAN(inode));
 865         }
 866 }
 867
 868 static void ext4_put_super(struct super_block *sb)
 869 {
 870         struct ext4_sb_info *sbi = EXT4_SB(sb);
 871         struct ext4_super_block *es = sbi->s_es;
 872         int i, err;
 873
 874         ext4_unregister_li_request(sb);
 875         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 876
 877         flush_workqueue(sbi->dio_unwritten_wq);
 878         destroy_workqueue(sbi->dio_unwritten_wq);
 879
 880         lock_super(sb);
 881         if (sbi->s_journal) {
 882                 err = jbd2_journal_destroy(sbi->s_journal);
 883                 sbi->s_journal = NULL;
 884                 if (err < 0)
 885                         ext4_abort(sb, "Couldn't clean up the journal");
 886         }
 887
 888         del_timer(&sbi->s_err_report);
 889         ext4_release_system_zone(sb);
 890         ext4_mb_release(sb);
 891         ext4_ext_release(sb);
 892         ext4_xattr_put_super(sb);
 893
 894         if (!(sb->s_flags & MS_RDONLY)) {
 895                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 896                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 897         }
 898         if (sb->s_dirt || !(sb->s_flags & MS_RDONLY))
 899                 ext4_commit_super(sb, 1);
 900
 901         if (sbi->s_proc) {
 902                 remove_proc_entry("options", sbi->s_proc);
 903                 remove_proc_entry(sb->s_id, ext4_proc_root);
 904         }
 905         kobject_del(&sbi->s_kobj);
 906
 907         for (i = 0; i < sbi->s_gdb_count; i++)
 908                 brelse(sbi->s_group_desc[i]);
 909         ext4_kvfree(sbi->s_group_desc);
 910         ext4_kvfree(sbi->s_flex_groups);
 911         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 912         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 913         percpu_counter_destroy(&sbi->s_dirs_counter);
 914         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 915         brelse(sbi->s_sbh);
 916 #ifdef CONFIG_QUOTA
 917         for (i = 0; i < MAXQUOTAS; i++)
 918                 kfree(sbi->s_qf_names[i]);
 919 #endif
 920
 921         /* Debugging code just in case the in-memory inode orphan list
 922          * isn't empty.  The on-disk one can be non-empty if we've
 923          * detected an error and taken the fs readonly, but the
 924          * in-memory list had better be clean by this point. */
 925         if (!list_empty(&sbi->s_orphan))
 926                 dump_orphan_list(sb, sbi);
 927         J_ASSERT(list_empty(&sbi->s_orphan));
 928
 929         invalidate_bdev(sb->s_bdev);
 930         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 931                 /*
 932                  * Invalidate the journal device's buffers.  We don't want them
 933                  * floating about in memory - the physical journal device may
 934                  * hotswapped, and it breaks the `ro-after' testing code.
 935                  */
 936                 sync_blockdev(sbi->journal_bdev);
 937                 invalidate_bdev(sbi->journal_bdev);
 938                 ext4_blkdev_remove(sbi);
 939         }
 940         if (sbi->s_mmp_tsk)
 941                 kthread_stop(sbi->s_mmp_tsk);
 942         sb->s_fs_info = NULL;
 943         /*
 944          * Now that we are completely done shutting down the
 945          * superblock, we need to actually destroy the kobject.
 946          */
 947         unlock_super(sb);
 948         kobject_put(&sbi->s_kobj);
 949         wait_for_completion(&sbi->s_kobj_unregister);
 950         if (sbi->s_chksum_driver)
 951                 crypto_free_shash(sbi->s_chksum_driver);
 952         kfree(sbi->s_blockgroup_lock);
 953         kfree(sbi);
 954 }
 955
 956 static struct kmem_cache *ext4_inode_cachep;
 957
 958 /*
 959  * Called inside transaction, so use GFP_NOFS
 960  */
 961 static struct inode *ext4_alloc_inode(struct super_block *sb)
 962 {
 963         struct ext4_inode_info *ei;
 964
 965         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 966         if (!ei)
 967                 return NULL;
 968
 969         ei->vfs_inode.i_version = 1;
 970         ei->vfs_inode.i_data.writeback_index = 0;
 971         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 972         INIT_LIST_HEAD(&ei->i_prealloc_list);
 973         spin_lock_init(&ei->i_prealloc_lock);
 974         ei->i_reserved_data_blocks = 0;
 975         ei->i_reserved_meta_blocks = 0;
 976         ei->i_allocated_meta_blocks = 0;
 977         ei->i_da_metadata_calc_len = 0;
 978         spin_lock_init(&(ei->i_block_reservation_lock));
 979 #ifdef CONFIG_QUOTA
 980         ei->i_reserved_quota = 0;
 981 #endif
 982         ei->jinode = NULL;
 983         INIT_LIST_HEAD(&ei->i_completed_io_list);
 984         spin_lock_init(&ei->i_completed_io_lock);
 985         ei->cur_aio_dio = NULL;
 986         ei->i_sync_tid = 0;
 987         ei->i_datasync_tid = 0;
 988         atomic_set(&ei->i_ioend_count, 0);
 989         atomic_set(&ei->i_aiodio_unwritten, 0);
 990
 991         return &ei->vfs_inode;
 992 }
 993
 994 static int ext4_drop_inode(struct inode *inode)
 995 {
 996         int drop = generic_drop_inode(inode);
 997
 998         trace_ext4_drop_inode(inode, drop);
 999         return drop;
1000 }
1001
1002 static void ext4_i_callback(struct rcu_head *head)
1003 {
1004         struct inode *inode = container_of(head, struct inode, i_rcu);
1005         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1006 }
1007
1008 static void ext4_destroy_inode(struct inode *inode)
1009 {
1010         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1011                 ext4_msg(inode->i_sb, KERN_ERR,
1012                          "Inode %lu (%p): orphan list check failed!",
1013                          inode->i_ino, EXT4_I(inode));
1014                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1015                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1016                                 true);
1017                 dump_stack();
1018         }
1019         call_rcu(&inode->i_rcu, ext4_i_callback);
1020 }
1021
1022 static void init_once(void *foo)
1023 {
1024         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1025
1026         INIT_LIST_HEAD(&ei->i_orphan);
1027 #ifdef CONFIG_EXT4_FS_XATTR
1028         init_rwsem(&ei->xattr_sem);
1029 #endif
1030         init_rwsem(&ei->i_data_sem);
1031         inode_init_once(&ei->vfs_inode);
1032 }
1033
1034 static int init_inodecache(void)
1035 {
1036         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
1037                                              sizeof(struct ext4_inode_info),
1038                                              0, (SLAB_RECLAIM_ACCOUNT|
1039                                                 SLAB_MEM_SPREAD),
1040                                              init_once);
1041         if (ext4_inode_cachep == NULL)
1042                 return -ENOMEM;
1043         return 0;
1044 }
1045
1046 static void destroy_inodecache(void)
1047 {
1048         kmem_cache_destroy(ext4_inode_cachep);
1049 }
1050
1051 void ext4_clear_inode(struct inode *inode)
1052 {
1053         invalidate_inode_buffers(inode);
1054         end_writeback(inode);
1055         dquot_drop(inode);
1056         ext4_discard_preallocations(inode);
1057         if (EXT4_I(inode)->jinode) {
1058                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1059                                                EXT4_I(inode)->jinode);
1060                 jbd2_free_inode(EXT4_I(inode)->jinode);
1061                 EXT4_I(inode)->jinode = NULL;
1062         }
1063 }
1064
1065 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1066                                         u64 ino, u32 generation)
1067 {
1068         struct inode *inode;
1069
1070         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1071                 return ERR_PTR(-ESTALE);
1072         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1073                 return ERR_PTR(-ESTALE);
1074
1075         /* iget isn't really right if the inode is currently unallocated!!
1076          *
1077          * ext4_read_inode will return a bad_inode if the inode had been
1078          * deleted, so we should be safe.
1079          *
1080          * Currently we don't know the generation for parent directory, so
1081          * a generation of 0 means "accept any"
1082          */
1083         inode = ext4_iget(sb, ino);
1084         if (IS_ERR(inode))
1085                 return ERR_CAST(inode);
1086         if (generation && inode->i_generation != generation) {
1087                 iput(inode);
1088                 return ERR_PTR(-ESTALE);
1089         }
1090
1091         return inode;
1092 }
1093
1094 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1095                                         int fh_len, int fh_type)
1096 {
1097         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1098                                     ext4_nfs_get_inode);
1099 }
1100
1101 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1102                                         int fh_len, int fh_type)
1103 {
1104         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1105                                     ext4_nfs_get_inode);
1106 }
1107
1108 /*
1109  * Try to release metadata pages (indirect blocks, directories) which are
1110  * mapped via the block device.  Since these pages could have journal heads
1111  * which would prevent try_to_free_buffers() from freeing them, we must use
1112  * jbd2 layer's try_to_free_buffers() function to release them.
1113  */
1114 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1115                                  gfp_t wait)
1116 {
1117         journal_t *journal = EXT4_SB(sb)->s_journal;
1118
1119         WARN_ON(PageChecked(page));
1120         if (!page_has_buffers(page))
1121                 return 0;
1122         if (journal)
1123                 return jbd2_journal_try_to_free_buffers(journal, page,
1124                                                         wait & ~__GFP_WAIT);
1125         return try_to_free_buffers(page);
1126 }
1127
1128 #ifdef CONFIG_QUOTA
1129 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1130 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1131
1132 static int ext4_write_dquot(struct dquot *dquot);
1133 static int ext4_acquire_dquot(struct dquot *dquot);
1134 static int ext4_release_dquot(struct dquot *dquot);
1135 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1136 static int ext4_write_info(struct super_block *sb, int type);
1137 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1138                          struct path *path);
1139 static int ext4_quota_off(struct super_block *sb, int type);
1140 static int ext4_quota_on_mount(struct super_block *sb, int type);
1141 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1142                                size_t len, loff_t off);
1143 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1144                                 const char *data, size_t len, loff_t off);
1145
1146 static const struct dquot_operations ext4_quota_operations = {
1147         .get_reserved_space = ext4_get_reserved_space,
1148         .write_dquot    = ext4_write_dquot,
1149         .acquire_dquot  = ext4_acquire_dquot,
1150         .release_dquot  = ext4_release_dquot,
1151         .mark_dirty     = ext4_mark_dquot_dirty,
1152         .write_info     = ext4_write_info,
1153         .alloc_dquot    = dquot_alloc,
1154         .destroy_dquot  = dquot_destroy,
1155 };
1156
1157 static const struct quotactl_ops ext4_qctl_operations = {
1158         .quota_on       = ext4_quota_on,
1159         .quota_off      = ext4_quota_off,
1160         .quota_sync     = dquot_quota_sync,
1161         .get_info       = dquot_get_dqinfo,
1162         .set_info       = dquot_set_dqinfo,
1163         .get_dqblk      = dquot_get_dqblk,
1164         .set_dqblk      = dquot_set_dqblk
1165 };
1166 #endif
1167
1168 static const struct super_operations ext4_sops = {
1169         .alloc_inode    = ext4_alloc_inode,
1170         .destroy_inode  = ext4_destroy_inode,
1171         .write_inode    = ext4_write_inode,
1172         .dirty_inode    = ext4_dirty_inode,
1173         .drop_inode     = ext4_drop_inode,
1174         .evict_inode    = ext4_evict_inode,
1175         .put_super      = ext4_put_super,
1176         .sync_fs        = ext4_sync_fs,
1177         .freeze_fs      = ext4_freeze,
1178         .unfreeze_fs    = ext4_unfreeze,
1179         .statfs         = ext4_statfs,
1180         .remount_fs     = ext4_remount,
1181         .show_options   = ext4_show_options,
1182 #ifdef CONFIG_QUOTA
1183         .quota_read     = ext4_quota_read,
1184         .quota_write    = ext4_quota_write,
1185 #endif
1186         .bdev_try_to_free_page = bdev_try_to_free_page,
1187 };
1188
1189 static const struct super_operations ext4_nojournal_sops = {
1190         .alloc_inode    = ext4_alloc_inode,
1191         .destroy_inode  = ext4_destroy_inode,
1192         .write_inode    = ext4_write_inode,
1193         .dirty_inode    = ext4_dirty_inode,
1194         .drop_inode     = ext4_drop_inode,
1195         .evict_inode    = ext4_evict_inode,
1196         .write_super    = ext4_write_super,
1197         .put_super      = ext4_put_super,
1198         .statfs         = ext4_statfs,
1199         .remount_fs     = ext4_remount,
1200         .show_options   = ext4_show_options,
1201 #ifdef CONFIG_QUOTA
1202         .quota_read     = ext4_quota_read,
1203         .quota_write    = ext4_quota_write,
1204 #endif
1205         .bdev_try_to_free_page = bdev_try_to_free_page,
1206 };
1207
1208 static const struct export_operations ext4_export_ops = {
1209         .fh_to_dentry = ext4_fh_to_dentry,
1210         .fh_to_parent = ext4_fh_to_parent,
1211         .get_parent = ext4_get_parent,
1212 };
1213
1214 enum {
1215         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1216         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1217         Opt_nouid32, Opt_debug, Opt_removed,
1218         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1219         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1220         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1221         Opt_journal_dev, Opt_journal_checksum, Opt_journal_async_commit,
1222         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1223         Opt_data_err_abort, Opt_data_err_ignore,
1224         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1225         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1226         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1227         Opt_usrquota, Opt_grpquota, Opt_i_version,
1228         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1229         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1230         Opt_inode_readahead_blks, Opt_journal_ioprio,
1231         Opt_dioread_nolock, Opt_dioread_lock,
1232         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1233 };
1234
1235 static const match_table_t tokens = {
1236         {Opt_bsd_df, "bsddf"},
1237         {Opt_minix_df, "minixdf"},
1238         {Opt_grpid, "grpid"},
1239         {Opt_grpid, "bsdgroups"},
1240         {Opt_nogrpid, "nogrpid"},
1241         {Opt_nogrpid, "sysvgroups"},
1242         {Opt_resgid, "resgid=%u"},
1243         {Opt_resuid, "resuid=%u"},
1244         {Opt_sb, "sb=%u"},
1245         {Opt_err_cont, "errors=continue"},
1246         {Opt_err_panic, "errors=panic"},
1247         {Opt_err_ro, "errors=remount-ro"},
1248         {Opt_nouid32, "nouid32"},
1249         {Opt_debug, "debug"},
1250         {Opt_removed, "oldalloc"},
1251         {Opt_removed, "orlov"},
1252         {Opt_user_xattr, "user_xattr"},
1253         {Opt_nouser_xattr, "nouser_xattr"},
1254         {Opt_acl, "acl"},
1255         {Opt_noacl, "noacl"},
1256         {Opt_noload, "norecovery"},
1257         {Opt_noload, "noload"},
1258         {Opt_removed, "nobh"},
1259         {Opt_removed, "bh"},
1260         {Opt_commit, "commit=%u"},
1261         {Opt_min_batch_time, "min_batch_time=%u"},
1262         {Opt_max_batch_time, "max_batch_time=%u"},
1263         {Opt_journal_dev, "journal_dev=%u"},
1264         {Opt_journal_checksum, "journal_checksum"},
1265         {Opt_journal_async_commit, "journal_async_commit"},
1266         {Opt_abort, "abort"},
1267         {Opt_data_journal, "data=journal"},
1268         {Opt_data_ordered, "data=ordered"},
1269         {Opt_data_writeback, "data=writeback"},
1270         {Opt_data_err_abort, "data_err=abort"},
1271         {Opt_data_err_ignore, "data_err=ignore"},
1272         {Opt_offusrjquota, "usrjquota="},
1273         {Opt_usrjquota, "usrjquota=%s"},
1274         {Opt_offgrpjquota, "grpjquota="},
1275         {Opt_grpjquota, "grpjquota=%s"},
1276         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1277         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1278         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1279         {Opt_grpquota, "grpquota"},
1280         {Opt_noquota, "noquota"},
1281         {Opt_quota, "quota"},
1282         {Opt_usrquota, "usrquota"},
1283         {Opt_barrier, "barrier=%u"},
1284         {Opt_barrier, "barrier"},
1285         {Opt_nobarrier, "nobarrier"},
1286         {Opt_i_version, "i_version"},
1287         {Opt_stripe, "stripe=%u"},
1288         {Opt_delalloc, "delalloc"},
1289         {Opt_nodelalloc, "nodelalloc"},
1290         {Opt_mblk_io_submit, "mblk_io_submit"},
1291         {Opt_nomblk_io_submit, "nomblk_io_submit"},
1292         {Opt_block_validity, "block_validity"},
1293         {Opt_noblock_validity, "noblock_validity"},
1294         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1295         {Opt_journal_ioprio, "journal_ioprio=%u"},
1296         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1297         {Opt_auto_da_alloc, "auto_da_alloc"},
1298         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1299         {Opt_dioread_nolock, "dioread_nolock"},
1300         {Opt_dioread_lock, "dioread_lock"},
1301         {Opt_discard, "discard"},
1302         {Opt_nodiscard, "nodiscard"},
1303         {Opt_init_itable, "init_itable=%u"},
1304         {Opt_init_itable, "init_itable"},
1305         {Opt_noinit_itable, "noinit_itable"},
1306         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1307         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1308         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1309         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1310         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1311         {Opt_err, NULL},
1312 };
1313
1314 static ext4_fsblk_t get_sb_block(void **data)
1315 {
1316         ext4_fsblk_t    sb_block;
1317         char            *options = (char *) *data;
1318
1319         if (!options || strncmp(options, "sb=", 3) != 0)
1320                 return 1;       /* Default location */
1321
1322         options += 3;
1323         /* TODO: use simple_strtoll with >32bit ext4 */
1324         sb_block = simple_strtoul(options, &options, 0);
1325         if (*options && *options != ',') {
1326                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1327                        (char *) *data);
1328                 return 1;
1329         }
1330         if (*options == ',')
1331                 options++;
1332         *data = (void *) options;
1333
1334         return sb_block;
1335 }
1336
1337 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1338 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1339         "Contact [email protected] if you think we should keep it.\n";
1340
1341 #ifdef CONFIG_QUOTA
1342 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1343 {
1344         struct ext4_sb_info *sbi = EXT4_SB(sb);
1345         char *qname;
1346
1347         if (sb_any_quota_loaded(sb) &&
1348                 !sbi->s_qf_names[qtype]) {
1349                 ext4_msg(sb, KERN_ERR,
1350                         "Cannot change journaled "
1351                         "quota options when quota turned on");
1352                 return -1;
1353         }
1354         qname = match_strdup(args);
1355         if (!qname) {
1356                 ext4_msg(sb, KERN_ERR,
1357                         "Not enough memory for storing quotafile name");
1358                 return -1;
1359         }
1360         if (sbi->s_qf_names[qtype] &&
1361                 strcmp(sbi->s_qf_names[qtype], qname)) {
1362                 ext4_msg(sb, KERN_ERR,
1363                         "%s quota file already specified", QTYPE2NAME(qtype));
1364                 kfree(qname);
1365                 return -1;
1366         }
1367         sbi->s_qf_names[qtype] = qname;
1368         if (strchr(sbi->s_qf_names[qtype], '/')) {
1369                 ext4_msg(sb, KERN_ERR,
1370                         "quotafile must be on filesystem root");
1371                 kfree(sbi->s_qf_names[qtype]);
1372                 sbi->s_qf_names[qtype] = NULL;
1373                 return -1;
1374         }
1375         set_opt(sb, QUOTA);
1376         return 1;
1377 }
1378
1379 static int clear_qf_name(struct super_block *sb, int qtype)
1380 {
1381
1382         struct ext4_sb_info *sbi = EXT4_SB(sb);
1383
1384         if (sb_any_quota_loaded(sb) &&
1385                 sbi->s_qf_names[qtype]) {
1386                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1387                         " when quota turned on");
1388                 return -1;
1389         }
1390         /*
1391          * The space will be released later when all options are confirmed
1392          * to be correct
1393          */
1394         sbi->s_qf_names[qtype] = NULL;
1395         return 1;
1396 }
1397 #endif
1398
1399 #define MOPT_SET        0x0001
1400 #define MOPT_CLEAR      0x0002
1401 #define MOPT_NOSUPPORT  0x0004
1402 #define MOPT_EXPLICIT   0x0008
1403 #define MOPT_CLEAR_ERR  0x0010
1404 #define MOPT_GTE0       0x0020
1405 #ifdef CONFIG_QUOTA
1406 #define MOPT_Q          0
1407 #define MOPT_QFMT       0x0040
1408 #else
1409 #define MOPT_Q          MOPT_NOSUPPORT
1410 #define MOPT_QFMT       MOPT_NOSUPPORT
1411 #endif
1412 #define MOPT_DATAJ      0x0080
1413
1414 static const struct mount_opts {
1415         int     token;
1416         int     mount_opt;
1417         int     flags;
1418 } ext4_mount_opts[] = {
1419         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1420         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1421         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1422         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1423         {Opt_mblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_SET},
1424         {Opt_nomblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_CLEAR},
1425         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1426         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1427         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_SET},
1428         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_CLEAR},
1429         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1430         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1431         {Opt_delalloc, EXT4_MOUNT_DELALLOC, MOPT_SET | MOPT_EXPLICIT},
1432         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC, MOPT_CLEAR | MOPT_EXPLICIT},
1433         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM, MOPT_SET},
1434         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1435                                     EXT4_MOUNT_JOURNAL_CHECKSUM), MOPT_SET},
1436         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_SET},
1437         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1438         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1439         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1440         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_SET},
1441         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_CLEAR},
1442         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1443         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1444         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1445         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1446         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1447         {Opt_commit, 0, MOPT_GTE0},
1448         {Opt_max_batch_time, 0, MOPT_GTE0},
1449         {Opt_min_batch_time, 0, MOPT_GTE0},
1450         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1451         {Opt_init_itable, 0, MOPT_GTE0},
1452         {Opt_stripe, 0, MOPT_GTE0},
1453         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_DATAJ},
1454         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_DATAJ},
1455         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA, MOPT_DATAJ},
1456 #ifdef CONFIG_EXT4_FS_XATTR
1457         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1458         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1459 #else
1460         {Opt_user_xattr, 0, MOPT_NOSUPPORT},
1461         {Opt_nouser_xattr, 0, MOPT_NOSUPPORT},
1462 #endif
1463 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1464         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1465         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1466 #else
1467         {Opt_acl, 0, MOPT_NOSUPPORT},
1468         {Opt_noacl, 0, MOPT_NOSUPPORT},
1469 #endif
1470         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1471         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1472         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1473         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1474                                                         MOPT_SET | MOPT_Q},
1475         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1476                                                         MOPT_SET | MOPT_Q},
1477         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1478                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1479         {Opt_usrjquota, 0, MOPT_Q},
1480         {Opt_grpjquota, 0, MOPT_Q},
1481         {Opt_offusrjquota, 0, MOPT_Q},
1482         {Opt_offgrpjquota, 0, MOPT_Q},
1483         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1484         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1485         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1486         {Opt_err, 0, 0}
1487 };
1488
1489 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1490                             substring_t *args, unsigned long *journal_devnum,
1491                             unsigned int *journal_ioprio, int is_remount)
1492 {
1493         struct ext4_sb_info *sbi = EXT4_SB(sb);
1494         const struct mount_opts *m;
1495         int arg = 0;
1496
1497 #ifdef CONFIG_QUOTA
1498         if (token == Opt_usrjquota)
1499                 return set_qf_name(sb, USRQUOTA, &args[0]);
1500         else if (token == Opt_grpjquota)
1501                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1502         else if (token == Opt_offusrjquota)
1503                 return clear_qf_name(sb, USRQUOTA);
1504         else if (token == Opt_offgrpjquota)
1505                 return clear_qf_name(sb, GRPQUOTA);
1506 #endif
1507         if (args->from && match_int(args, &arg))
1508                 return -1;
1509         switch (token) {
1510         case Opt_noacl:
1511         case Opt_nouser_xattr:
1512                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1513                 break;
1514         case Opt_sb:
1515                 return 1;       /* handled by get_sb_block() */
1516         case Opt_removed:
1517                 ext4_msg(sb, KERN_WARNING,
1518                          "Ignoring removed %s option", opt);
1519                 return 1;
1520         case Opt_resuid:
1521                 sbi->s_resuid = arg;
1522                 return 1;
1523         case Opt_resgid:
1524                 sbi->s_resgid = arg;
1525                 return 1;
1526         case Opt_abort:
1527                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1528                 return 1;
1529         case Opt_i_version:
1530                 sb->s_flags |= MS_I_VERSION;
1531                 return 1;
1532         case Opt_journal_dev:
1533                 if (is_remount) {
1534                         ext4_msg(sb, KERN_ERR,
1535                                  "Cannot specify journal on remount");
1536                         return -1;
1537                 }
1538                 *journal_devnum = arg;
1539                 return 1;
1540         case Opt_journal_ioprio:
1541                 if (arg < 0 || arg > 7)
1542                         return -1;
1543                 *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1544                 return 1;
1545         }
1546
1547         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1548                 if (token != m->token)
1549                         continue;
1550                 if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1551                         return -1;
1552                 if (m->flags & MOPT_EXPLICIT)
1553                         set_opt2(sb, EXPLICIT_DELALLOC);
1554                 if (m->flags & MOPT_CLEAR_ERR)
1555                         clear_opt(sb, ERRORS_MASK);
1556                 if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1557                         ext4_msg(sb, KERN_ERR, "Cannot change quota "
1558                                  "options when quota turned on");
1559                         return -1;
1560                 }
1561
1562                 if (m->flags & MOPT_NOSUPPORT) {
1563                         ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1564                 } else if (token == Opt_commit) {
1565                         if (arg == 0)
1566                                 arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1567                         sbi->s_commit_interval = HZ * arg;
1568                 } else if (token == Opt_max_batch_time) {
1569                         if (arg == 0)
1570                                 arg = EXT4_DEF_MAX_BATCH_TIME;
1571                         sbi->s_max_batch_time = arg;
1572                 } else if (token == Opt_min_batch_time) {
1573                         sbi->s_min_batch_time = arg;
1574                 } else if (token == Opt_inode_readahead_blks) {
1575                         if (arg > (1 << 30))
1576                                 return -1;
1577                         if (arg && !is_power_of_2(arg)) {
1578                                 ext4_msg(sb, KERN_ERR,
1579                                          "EXT4-fs: inode_readahead_blks"
1580                                          " must be a power of 2");
1581                                 return -1;
1582                         }
1583                         sbi->s_inode_readahead_blks = arg;
1584                 } else if (token == Opt_init_itable) {
1585                         set_opt(sb, INIT_INODE_TABLE);
1586                         if (!args->from)
1587                                 arg = EXT4_DEF_LI_WAIT_MULT;
1588                         sbi->s_li_wait_mult = arg;
1589                 } else if (token == Opt_stripe) {
1590                         sbi->s_stripe = arg;
1591                 } else if (m->flags & MOPT_DATAJ) {
1592                         if (is_remount) {
1593                                 if (!sbi->s_journal)
1594                                         ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1595                                 else if (test_opt(sb, DATA_FLAGS) !=
1596                                          m->mount_opt) {
1597                                         ext4_msg(sb, KERN_ERR,
1598                                          "Cannot change data mode on remount");
1599                                         return -1;
1600                                 }
1601                         } else {
1602                                 clear_opt(sb, DATA_FLAGS);
1603                                 sbi->s_mount_opt |= m->mount_opt;
1604                         }
1605 #ifdef CONFIG_QUOTA
1606                 } else if (m->flags & MOPT_QFMT) {
1607                         if (sb_any_quota_loaded(sb) &&
1608                             sbi->s_jquota_fmt != m->mount_opt) {
1609                                 ext4_msg(sb, KERN_ERR, "Cannot "
1610                                          "change journaled quota options "
1611                                          "when quota turned on");
1612                                 return -1;
1613                         }
1614                         sbi->s_jquota_fmt = m->mount_opt;
1615 #endif
1616                 } else {
1617                         if (!args->from)
1618                                 arg = 1;
1619                         if (m->flags & MOPT_CLEAR)
1620                                 arg = !arg;
1621                         else if (unlikely(!(m->flags & MOPT_SET))) {
1622                                 ext4_msg(sb, KERN_WARNING,
1623                                          "buggy handling of option %s", opt);
1624                                 WARN_ON(1);
1625                                 return -1;
1626                         }
1627                         if (arg != 0)
1628                                 sbi->s_mount_opt |= m->mount_opt;
1629                         else
1630                                 sbi->s_mount_opt &= ~m->mount_opt;
1631                 }
1632                 return 1;
1633         }
1634         ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1635                  "or missing value", opt);
1636         return -1;
1637 }
1638
1639 static int parse_options(char *options, struct super_block *sb,
1640                          unsigned long *journal_devnum,
1641                          unsigned int *journal_ioprio,
1642                          int is_remount)
1643 {
1644 #ifdef CONFIG_QUOTA
1645         struct ext4_sb_info *sbi = EXT4_SB(sb);
1646 #endif
1647         char *p;
1648         substring_t args[MAX_OPT_ARGS];
1649         int token;
1650
1651         if (!options)
1652                 return 1;
1653
1654         while ((p = strsep(&options, ",")) != NULL) {
1655                 if (!*p)
1656                         continue;
1657                 /*
1658                  * Initialize args struct so we know whether arg was
1659                  * found; some options take optional arguments.
1660                  */
1661                 args[0].to = args[0].from = 0;
1662                 token = match_token(p, tokens, args);
1663                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1664                                      journal_ioprio, is_remount) < 0)
1665                         return 0;
1666         }
1667 #ifdef CONFIG_QUOTA
1668         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1669                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1670                         clear_opt(sb, USRQUOTA);
1671
1672                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1673                         clear_opt(sb, GRPQUOTA);
1674
1675                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1676                         ext4_msg(sb, KERN_ERR, "old and new quota "
1677                                         "format mixing");
1678                         return 0;
1679                 }
1680
1681                 if (!sbi->s_jquota_fmt) {
1682                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1683                                         "not specified");
1684                         return 0;
1685                 }
1686         } else {
1687                 if (sbi->s_jquota_fmt) {
1688                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1689                                         "specified with no journaling "
1690                                         "enabled");
1691                         return 0;
1692                 }
1693         }
1694 #endif
1695         return 1;
1696 }
1697
1698 static inline void ext4_show_quota_options(struct seq_file *seq,
1699                                            struct super_block *sb)
1700 {
1701 #if defined(CONFIG_QUOTA)
1702         struct ext4_sb_info *sbi = EXT4_SB(sb);
1703
1704         if (sbi->s_jquota_fmt) {
1705                 char *fmtname = "";
1706
1707                 switch (sbi->s_jquota_fmt) {
1708                 case QFMT_VFS_OLD:
1709                         fmtname = "vfsold";
1710                         break;
1711                 case QFMT_VFS_V0:
1712                         fmtname = "vfsv0";
1713                         break;
1714                 case QFMT_VFS_V1:
1715                         fmtname = "vfsv1";
1716                         break;
1717                 }
1718                 seq_printf(seq, ",jqfmt=%s", fmtname);
1719         }
1720
1721         if (sbi->s_qf_names[USRQUOTA])
1722                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1723
1724         if (sbi->s_qf_names[GRPQUOTA])
1725                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1726
1727         if (test_opt(sb, USRQUOTA))
1728                 seq_puts(seq, ",usrquota");
1729
1730         if (test_opt(sb, GRPQUOTA))
1731                 seq_puts(seq, ",grpquota");
1732 #endif
1733 }
1734
1735 static const char *token2str(int token)
1736 {
1737         static const struct match_token *t;
1738
1739         for (t = tokens; t->token != Opt_err; t++)
1740                 if (t->token == token && !strchr(t->pattern, '='))
1741                         break;
1742         return t->pattern;
1743 }
1744
1745 /*
1746  * Show an option if
1747  *  - it's set to a non-default value OR
1748  *  - if the per-sb default is different from the global default
1749  */
1750 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1751                               int nodefs)
1752 {
1753         struct ext4_sb_info *sbi = EXT4_SB(sb);
1754         struct ext4_super_block *es = sbi->s_es;
1755         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1756         const struct mount_opts *m;
1757         char sep = nodefs ? '\n' : ',';
1758
1759 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1760 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1761
1762         if (sbi->s_sb_block != 1)
1763                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1764
1765         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1766                 int want_set = m->flags & MOPT_SET;
1767                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1768                     (m->flags & MOPT_CLEAR_ERR))
1769                         continue;
1770                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1771                         continue; /* skip if same as the default */
1772                 if ((want_set &&
1773                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1774                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1775                         continue; /* select Opt_noFoo vs Opt_Foo */
1776                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1777         }
1778
1779         if (nodefs || sbi->s_resuid != EXT4_DEF_RESUID ||
1780             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1781                 SEQ_OPTS_PRINT("resuid=%u", sbi->s_resuid);
1782         if (nodefs || sbi->s_resgid != EXT4_DEF_RESGID ||
1783             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1784                 SEQ_OPTS_PRINT("resgid=%u", sbi->s_resgid);
1785         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1786         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1787                 SEQ_OPTS_PUTS("errors=remount-ro");
1788         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1789                 SEQ_OPTS_PUTS("errors=continue");
1790         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1791                 SEQ_OPTS_PUTS("errors=panic");
1792         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1793                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1794         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1795                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1796         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1797                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1798         if (sb->s_flags & MS_I_VERSION)
1799                 SEQ_OPTS_PUTS("i_version");
1800         if (nodefs || sbi->s_stripe)
1801                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1802         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1803                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1804                         SEQ_OPTS_PUTS("data=journal");
1805                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1806                         SEQ_OPTS_PUTS("data=ordered");
1807                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1808                         SEQ_OPTS_PUTS("data=writeback");
1809         }
1810         if (nodefs ||
1811             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1812                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1813                                sbi->s_inode_readahead_blks);
1814
1815         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1816                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1817                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1818
1819         ext4_show_quota_options(seq, sb);
1820         return 0;
1821 }
1822
1823 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1824 {
1825         return _ext4_show_options(seq, root->d_sb, 0);
1826 }
1827
1828 static int options_seq_show(struct seq_file *seq, void *offset)
1829 {
1830         struct super_block *sb = seq->private;
1831         int rc;
1832
1833         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1834         rc = _ext4_show_options(seq, sb, 1);
1835         seq_puts(seq, "\n");
1836         return rc;
1837 }
1838
1839 static int options_open_fs(struct inode *inode, struct file *file)
1840 {
1841         return single_open(file, options_seq_show, PDE(inode)->data);
1842 }
1843
1844 static const struct file_operations ext4_seq_options_fops = {
1845         .owner = THIS_MODULE,
1846         .open = options_open_fs,
1847         .read = seq_read,
1848         .llseek = seq_lseek,
1849         .release = single_release,
1850 };
1851
1852 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1853                             int read_only)
1854 {
1855         struct ext4_sb_info *sbi = EXT4_SB(sb);
1856         int res = 0;
1857
1858         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1859                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1860                          "forcing read-only mode");
1861                 res = MS_RDONLY;
1862         }
1863         if (read_only)
1864                 goto done;
1865         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1866                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1867                          "running e2fsck is recommended");
1868         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1869                 ext4_msg(sb, KERN_WARNING,
1870                          "warning: mounting fs with errors, "
1871                          "running e2fsck is recommended");
1872         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1873                  le16_to_cpu(es->s_mnt_count) >=
1874                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1875                 ext4_msg(sb, KERN_WARNING,
1876                          "warning: maximal mount count reached, "
1877                          "running e2fsck is recommended");
1878         else if (le32_to_cpu(es->s_checkinterval) &&
1879                 (le32_to_cpu(es->s_lastcheck) +
1880                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1881                 ext4_msg(sb, KERN_WARNING,
1882                          "warning: checktime reached, "
1883                          "running e2fsck is recommended");
1884         if (!sbi->s_journal)
1885                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1886         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1887                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1888         le16_add_cpu(&es->s_mnt_count, 1);
1889         es->s_mtime = cpu_to_le32(get_seconds());
1890         ext4_update_dynamic_rev(sb);
1891         if (sbi->s_journal)
1892                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1893
1894         ext4_commit_super(sb, 1);
1895 done:
1896         if (test_opt(sb, DEBUG))
1897                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1898                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1899                         sb->s_blocksize,
1900                         sbi->s_groups_count,
1901                         EXT4_BLOCKS_PER_GROUP(sb),
1902                         EXT4_INODES_PER_GROUP(sb),
1903                         sbi->s_mount_opt, sbi->s_mount_opt2);
1904
1905         cleancache_init_fs(sb);
1906         return res;
1907 }
1908
1909 static int ext4_fill_flex_info(struct super_block *sb)
1910 {
1911         struct ext4_sb_info *sbi = EXT4_SB(sb);
1912         struct ext4_group_desc *gdp = NULL;
1913         ext4_group_t flex_group_count;
1914         ext4_group_t flex_group;
1915         unsigned int groups_per_flex = 0;
1916         size_t size;
1917         int i;
1918
1919         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1920         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1921                 sbi->s_log_groups_per_flex = 0;
1922                 return 1;
1923         }
1924         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1925
1926         /* We allocate both existing and potentially added groups */
1927         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1928                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1929                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1930         size = flex_group_count * sizeof(struct flex_groups);
1931         sbi->s_flex_groups = ext4_kvzalloc(size, GFP_KERNEL);
1932         if (sbi->s_flex_groups == NULL) {
1933                 ext4_msg(sb, KERN_ERR, "not enough memory for %u flex groups",
1934                          flex_group_count);
1935                 goto failed;
1936         }
1937
1938         for (i = 0; i < sbi->s_groups_count; i++) {
1939                 gdp = ext4_get_group_desc(sb, i, NULL);
1940
1941                 flex_group = ext4_flex_group(sbi, i);
1942                 atomic_add(ext4_free_inodes_count(sb, gdp),
1943                            &sbi->s_flex_groups[flex_group].free_inodes);
1944                 atomic_add(ext4_free_group_clusters(sb, gdp),
1945                            &sbi->s_flex_groups[flex_group].free_clusters);
1946                 atomic_add(ext4_used_dirs_count(sb, gdp),
1947                            &sbi->s_flex_groups[flex_group].used_dirs);
1948         }
1949
1950         return 1;
1951 failed:
1952         return 0;
1953 }
1954
1955 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1956                             struct ext4_group_desc *gdp)
1957 {
1958         __u16 crc = 0;
1959
1960         if (sbi->s_es->s_feature_ro_compat &
1961             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1962                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1963                 __le32 le_group = cpu_to_le32(block_group);
1964
1965                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1966                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1967                 crc = crc16(crc, (__u8 *)gdp, offset);
1968                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1969                 /* for checksum of struct ext4_group_desc do the rest...*/
1970                 if ((sbi->s_es->s_feature_incompat &
1971                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1972                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1973                         crc = crc16(crc, (__u8 *)gdp + offset,
1974                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1975                                         offset);
1976         }
1977
1978         return cpu_to_le16(crc);
1979 }
1980
1981 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1982                                 struct ext4_group_desc *gdp)
1983 {
1984         if ((sbi->s_es->s_feature_ro_compat &
1985              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1986             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1987                 return 0;
1988
1989         return 1;
1990 }
1991
1992 /* Called at mount-time, super-block is locked */
1993 static int ext4_check_descriptors(struct super_block *sb,
1994                                   ext4_group_t *first_not_zeroed)
1995 {
1996         struct ext4_sb_info *sbi = EXT4_SB(sb);
1997         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1998         ext4_fsblk_t last_block;
1999         ext4_fsblk_t block_bitmap;
2000         ext4_fsblk_t inode_bitmap;
2001         ext4_fsblk_t inode_table;
2002         int flexbg_flag = 0;
2003         ext4_group_t i, grp = sbi->s_groups_count;
2004
2005         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2006                 flexbg_flag = 1;
2007
2008         ext4_debug("Checking group descriptors");
2009
2010         for (i = 0; i < sbi->s_groups_count; i++) {
2011                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2012
2013                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2014                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2015                 else
2016                         last_block = first_block +
2017                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2018
2019                 if ((grp == sbi->s_groups_count) &&
2020                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2021                         grp = i;
2022
2023                 block_bitmap = ext4_block_bitmap(sb, gdp);
2024                 if (block_bitmap < first_block || block_bitmap > last_block) {
2025                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2026                                "Block bitmap for group %u not in group "
2027                                "(block %llu)!", i, block_bitmap);
2028                         return 0;
2029                 }
2030                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2031                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2032                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2033                                "Inode bitmap for group %u not in group "
2034                                "(block %llu)!", i, inode_bitmap);
2035                         return 0;
2036                 }
2037                 inode_table = ext4_inode_table(sb, gdp);
2038                 if (inode_table < first_block ||
2039                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2040                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2041                                "Inode table for group %u not in group "
2042                                "(block %llu)!", i, inode_table);
2043                         return 0;
2044                 }
2045                 ext4_lock_group(sb, i);
2046                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
2047                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2048                                  "Checksum for group %u failed (%u!=%u)",
2049                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2050                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2051                         if (!(sb->s_flags & MS_RDONLY)) {
2052                                 ext4_unlock_group(sb, i);
2053                                 return 0;
2054                         }
2055                 }
2056                 ext4_unlock_group(sb, i);
2057                 if (!flexbg_flag)
2058                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2059         }
2060         if (NULL != first_not_zeroed)
2061                 *first_not_zeroed = grp;
2062
2063         ext4_free_blocks_count_set(sbi->s_es,
2064                                    EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2065         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2066         return 1;
2067 }
2068
2069 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2070  * the superblock) which were deleted from all directories, but held open by
2071  * a process at the time of a crash.  We walk the list and try to delete these
2072  * inodes at recovery time (only with a read-write filesystem).
2073  *
2074  * In order to keep the orphan inode chain consistent during traversal (in
2075  * case of crash during recovery), we link each inode into the superblock
2076  * orphan list_head and handle it the same way as an inode deletion during
2077  * normal operation (which journals the operations for us).
2078  *
2079  * We only do an iget() and an iput() on each inode, which is very safe if we
2080  * accidentally point at an in-use or already deleted inode.  The worst that
2081  * can happen in this case is that we get a "bit already cleared" message from
2082  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2083  * e2fsck was run on this filesystem, and it must have already done the orphan
2084  * inode cleanup for us, so we can safely abort without any further action.
2085  */
2086 static void ext4_orphan_cleanup(struct super_block *sb,
2087                                 struct ext4_super_block *es)
2088 {
2089         unsigned int s_flags = sb->s_flags;
2090         int nr_orphans = 0, nr_truncates = 0;
2091 #ifdef CONFIG_QUOTA
2092         int i;
2093 #endif
2094         if (!es->s_last_orphan) {
2095                 jbd_debug(4, "no orphan inodes to clean up\n");
2096                 return;
2097         }
2098
2099         if (bdev_read_only(sb->s_bdev)) {
2100                 ext4_msg(sb, KERN_ERR, "write access "
2101                         "unavailable, skipping orphan cleanup");
2102                 return;
2103         }
2104
2105         /* Check if feature set would not allow a r/w mount */
2106         if (!ext4_feature_set_ok(sb, 0)) {
2107                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2108                          "unknown ROCOMPAT features");
2109                 return;
2110         }
2111
2112         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2113                 if (es->s_last_orphan)
2114                         jbd_debug(1, "Errors on filesystem, "
2115                                   "clearing orphan list.\n");
2116                 es->s_last_orphan = 0;
2117                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2118                 return;
2119         }
2120
2121         if (s_flags & MS_RDONLY) {
2122                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2123                 sb->s_flags &= ~MS_RDONLY;
2124         }
2125 #ifdef CONFIG_QUOTA
2126         /* Needed for iput() to work correctly and not trash data */
2127         sb->s_flags |= MS_ACTIVE;
2128         /* Turn on quotas so that they are updated correctly */
2129         for (i = 0; i < MAXQUOTAS; i++) {
2130                 if (EXT4_SB(sb)->s_qf_names[i]) {
2131                         int ret = ext4_quota_on_mount(sb, i);
2132                         if (ret < 0)
2133                                 ext4_msg(sb, KERN_ERR,
2134                                         "Cannot turn on journaled "
2135                                         "quota: error %d", ret);
2136                 }
2137         }
2138 #endif
2139
2140         while (es->s_last_orphan) {
2141                 struct inode *inode;
2142
2143                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2144                 if (IS_ERR(inode)) {
2145                         es->s_last_orphan = 0;
2146                         break;
2147                 }
2148
2149                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2150                 dquot_initialize(inode);
2151                 if (inode->i_nlink) {
2152                         ext4_msg(sb, KERN_DEBUG,
2153                                 "%s: truncating inode %lu to %lld bytes",
2154                                 __func__, inode->i_ino, inode->i_size);
2155                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2156                                   inode->i_ino, inode->i_size);
2157                         ext4_truncate(inode);
2158                         nr_truncates++;
2159                 } else {
2160                         ext4_msg(sb, KERN_DEBUG,
2161                                 "%s: deleting unreferenced inode %lu",
2162                                 __func__, inode->i_ino);
2163                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2164                                   inode->i_ino);
2165                         nr_orphans++;
2166                 }
2167                 iput(inode);  /* The delete magic happens here! */
2168         }
2169
2170 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2171
2172         if (nr_orphans)
2173                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2174                        PLURAL(nr_orphans));
2175         if (nr_truncates)
2176                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2177                        PLURAL(nr_truncates));
2178 #ifdef CONFIG_QUOTA
2179         /* Turn quotas off */
2180         for (i = 0; i < MAXQUOTAS; i++) {
2181                 if (sb_dqopt(sb)->files[i])
2182                         dquot_quota_off(sb, i);
2183         }
2184 #endif
2185         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2186 }
2187
2188 /*
2189  * Maximal extent format file size.
2190  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2191  * extent format containers, within a sector_t, and within i_blocks
2192  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2193  * so that won't be a limiting factor.
2194  *
2195  * However there is other limiting factor. We do store extents in the form
2196  * of starting block and length, hence the resulting length of the extent
2197  * covering maximum file size must fit into on-disk format containers as
2198  * well. Given that length is always by 1 unit bigger than max unit (because
2199  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2200  *
2201  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2202  */
2203 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2204 {
2205         loff_t res;
2206         loff_t upper_limit = MAX_LFS_FILESIZE;
2207
2208         /* small i_blocks in vfs inode? */
2209         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2210                 /*
2211                  * CONFIG_LBDAF is not enabled implies the inode
2212                  * i_block represent total blocks in 512 bytes
2213                  * 32 == size of vfs inode i_blocks * 8
2214                  */
2215                 upper_limit = (1LL << 32) - 1;
2216
2217                 /* total blocks in file system block size */
2218                 upper_limit >>= (blkbits - 9);
2219                 upper_limit <<= blkbits;
2220         }
2221
2222         /*
2223          * 32-bit extent-start container, ee_block. We lower the maxbytes
2224          * by one fs block, so ee_len can cover the extent of maximum file
2225          * size
2226          */
2227         res = (1LL << 32) - 1;
2228         res <<= blkbits;
2229
2230         /* Sanity check against vm- & vfs- imposed limits */
2231         if (res > upper_limit)
2232                 res = upper_limit;
2233
2234         return res;
2235 }
2236
2237 /*
2238  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2239  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2240  * We need to be 1 filesystem block less than the 2^48 sector limit.
2241  */
2242 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2243 {
2244         loff_t res = EXT4_NDIR_BLOCKS;
2245         int meta_blocks;
2246         loff_t upper_limit;
2247         /* This is calculated to be the largest file size for a dense, block
2248          * mapped file such that the file's total number of 512-byte sectors,
2249          * including data and all indirect blocks, does not exceed (2^48 - 1).
2250          *
2251          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2252          * number of 512-byte sectors of the file.
2253          */
2254
2255         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2256                 /*
2257                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2258                  * the inode i_block field represents total file blocks in
2259                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2260                  */
2261                 upper_limit = (1LL << 32) - 1;
2262
2263                 /* total blocks in file system block size */
2264                 upper_limit >>= (bits - 9);
2265
2266         } else {
2267                 /*
2268                  * We use 48 bit ext4_inode i_blocks
2269                  * With EXT4_HUGE_FILE_FL set the i_blocks
2270                  * represent total number of blocks in
2271                  * file system block size
2272                  */
2273                 upper_limit = (1LL << 48) - 1;
2274
2275         }
2276
2277         /* indirect blocks */
2278         meta_blocks = 1;
2279         /* double indirect blocks */
2280         meta_blocks += 1 + (1LL << (bits-2));
2281         /* tripple indirect blocks */
2282         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2283
2284         upper_limit -= meta_blocks;
2285         upper_limit <<= bits;
2286
2287         res += 1LL << (bits-2);
2288         res += 1LL << (2*(bits-2));
2289         res += 1LL << (3*(bits-2));
2290         res <<= bits;
2291         if (res > upper_limit)
2292                 res = upper_limit;
2293
2294         if (res > MAX_LFS_FILESIZE)
2295                 res = MAX_LFS_FILESIZE;
2296
2297         return res;
2298 }
2299
2300 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2301                                    ext4_fsblk_t logical_sb_block, int nr)
2302 {
2303         struct ext4_sb_info *sbi = EXT4_SB(sb);
2304         ext4_group_t bg, first_meta_bg;
2305         int has_super = 0;
2306
2307         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2308
2309         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2310             nr < first_meta_bg)
2311                 return logical_sb_block + nr + 1;
2312         bg = sbi->s_desc_per_block * nr;
2313         if (ext4_bg_has_super(sb, bg))
2314                 has_super = 1;
2315
2316         return (has_super + ext4_group_first_block_no(sb, bg));
2317 }
2318
2319 /**
2320  * ext4_get_stripe_size: Get the stripe size.
2321  * @sbi: In memory super block info
2322  *
2323  * If we have specified it via mount option, then
2324  * use the mount option value. If the value specified at mount time is
2325  * greater than the blocks per group use the super block value.
2326  * If the super block value is greater than blocks per group return 0.
2327  * Allocator needs it be less than blocks per group.
2328  *
2329  */
2330 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2331 {
2332         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2333         unsigned long stripe_width =
2334                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2335         int ret;
2336
2337         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2338                 ret = sbi->s_stripe;
2339         else if (stripe_width <= sbi->s_blocks_per_group)
2340                 ret = stripe_width;
2341         else if (stride <= sbi->s_blocks_per_group)
2342                 ret = stride;
2343         else
2344                 ret = 0;
2345
2346         /*
2347          * If the stripe width is 1, this makes no sense and
2348          * we set it to 0 to turn off stripe handling code.
2349          */
2350         if (ret <= 1)
2351                 ret = 0;
2352
2353         return ret;
2354 }
2355
2356 /* sysfs supprt */
2357
2358 struct ext4_attr {
2359         struct attribute attr;
2360         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2361         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2362                          const char *, size_t);
2363         int offset;
2364 };
2365
2366 static int parse_strtoul(const char *buf,
2367                 unsigned long max, unsigned long *value)
2368 {
2369         char *endp;
2370
2371         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2372         endp = skip_spaces(endp);
2373         if (*endp || *value > max)
2374                 return -EINVAL;
2375
2376         return 0;
2377 }
2378
2379 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2380                                               struct ext4_sb_info *sbi,
2381                                               char *buf)
2382 {
2383         return snprintf(buf, PAGE_SIZE, "%llu\n",
2384                 (s64) EXT4_C2B(sbi,
2385                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2386 }
2387
2388 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2389                                          struct ext4_sb_info *sbi, char *buf)
2390 {
2391         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2392
2393         if (!sb->s_bdev->bd_part)
2394                 return snprintf(buf, PAGE_SIZE, "0\n");
2395         return snprintf(buf, PAGE_SIZE, "%lu\n",
2396                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2397                          sbi->s_sectors_written_start) >> 1);
2398 }
2399
2400 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2401                                           struct ext4_sb_info *sbi, char *buf)
2402 {
2403         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2404
2405         if (!sb->s_bdev->bd_part)
2406                 return snprintf(buf, PAGE_SIZE, "0\n");
2407         return snprintf(buf, PAGE_SIZE, "%llu\n",
2408                         (unsigned long long)(sbi->s_kbytes_written +
2409                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2410                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2411 }
2412
2413 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2414                                           struct ext4_sb_info *sbi,
2415                                           const char *buf, size_t count)
2416 {
2417         unsigned long t;
2418
2419         if (parse_strtoul(buf, 0x40000000, &t))
2420                 return -EINVAL;
2421
2422         if (t && !is_power_of_2(t))
2423                 return -EINVAL;
2424
2425         sbi->s_inode_readahead_blks = t;
2426         return count;
2427 }
2428
2429 static ssize_t sbi_ui_show(struct ext4_attr *a,
2430                            struct ext4_sb_info *sbi, char *buf)
2431 {
2432         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2433
2434         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2435 }
2436
2437 static ssize_t sbi_ui_store(struct ext4_attr *a,
2438                             struct ext4_sb_info *sbi,
2439                             const char *buf, size_t count)
2440 {
2441         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2442         unsigned long t;
2443
2444         if (parse_strtoul(buf, 0xffffffff, &t))
2445                 return -EINVAL;
2446         *ui = t;
2447         return count;
2448 }
2449
2450 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2451 static struct ext4_attr ext4_attr_##_name = {                   \
2452         .attr = {.name = __stringify(_name), .mode = _mode },   \
2453         .show   = _show,                                        \
2454         .store  = _store,                                       \
2455         .offset = offsetof(struct ext4_sb_info, _elname),       \
2456 }
2457 #define EXT4_ATTR(name, mode, show, store) \
2458 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2459
2460 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2461 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2462 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2463 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2464         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2465 #define ATTR_LIST(name) &ext4_attr_##name.attr
2466
2467 EXT4_RO_ATTR(delayed_allocation_blocks);
2468 EXT4_RO_ATTR(session_write_kbytes);
2469 EXT4_RO_ATTR(lifetime_write_kbytes);
2470 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2471                  inode_readahead_blks_store, s_inode_readahead_blks);
2472 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2473 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2474 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2475 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2476 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2477 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2478 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2479 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2480
2481 static struct attribute *ext4_attrs[] = {
2482         ATTR_LIST(delayed_allocation_blocks),
2483         ATTR_LIST(session_write_kbytes),
2484         ATTR_LIST(lifetime_write_kbytes),
2485         ATTR_LIST(inode_readahead_blks),
2486         ATTR_LIST(inode_goal),
2487         ATTR_LIST(mb_stats),
2488         ATTR_LIST(mb_max_to_scan),
2489         ATTR_LIST(mb_min_to_scan),
2490         ATTR_LIST(mb_order2_req),
2491         ATTR_LIST(mb_stream_req),
2492         ATTR_LIST(mb_group_prealloc),
2493         ATTR_LIST(max_writeback_mb_bump),
2494         NULL,
2495 };
2496
2497 /* Features this copy of ext4 supports */
2498 EXT4_INFO_ATTR(lazy_itable_init);
2499 EXT4_INFO_ATTR(batched_discard);
2500
2501 static struct attribute *ext4_feat_attrs[] = {
2502         ATTR_LIST(lazy_itable_init),
2503         ATTR_LIST(batched_discard),
2504         NULL,
2505 };
2506
2507 static ssize_t ext4_attr_show(struct kobject *kobj,
2508                               struct attribute *attr, char *buf)
2509 {
2510         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2511                                                 s_kobj);
2512         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2513
2514         return a->show ? a->show(a, sbi, buf) : 0;
2515 }
2516
2517 static ssize_t ext4_attr_store(struct kobject *kobj,
2518                                struct attribute *attr,
2519                                const char *buf, size_t len)
2520 {
2521         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2522                                                 s_kobj);
2523         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2524
2525         return a->store ? a->store(a, sbi, buf, len) : 0;
2526 }
2527
2528 static void ext4_sb_release(struct kobject *kobj)
2529 {
2530         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2531                                                 s_kobj);
2532         complete(&sbi->s_kobj_unregister);
2533 }
2534
2535 static const struct sysfs_ops ext4_attr_ops = {
2536         .show   = ext4_attr_show,
2537         .store  = ext4_attr_store,
2538 };
2539
2540 static struct kobj_type ext4_ktype = {
2541         .default_attrs  = ext4_attrs,
2542         .sysfs_ops      = &ext4_attr_ops,
2543         .release        = ext4_sb_release,
2544 };
2545
2546 static void ext4_feat_release(struct kobject *kobj)
2547 {
2548         complete(&ext4_feat->f_kobj_unregister);
2549 }
2550
2551 static struct kobj_type ext4_feat_ktype = {
2552         .default_attrs  = ext4_feat_attrs,
2553         .sysfs_ops      = &ext4_attr_ops,
2554         .release        = ext4_feat_release,
2555 };
2556
2557 /*
2558  * Check whether this filesystem can be mounted based on
2559  * the features present and the RDONLY/RDWR mount requested.
2560  * Returns 1 if this filesystem can be mounted as requested,
2561  * 0 if it cannot be.
2562  */
2563 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2564 {
2565         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2566                 ext4_msg(sb, KERN_ERR,
2567                         "Couldn't mount because of "
2568                         "unsupported optional features (%x)",
2569                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2570                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2571                 return 0;
2572         }
2573
2574         if (readonly)
2575                 return 1;
2576
2577         /* Check that feature set is OK for a read-write mount */
2578         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2579                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2580                          "unsupported optional features (%x)",
2581                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2582                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2583                 return 0;
2584         }
2585         /*
2586          * Large file size enabled file system can only be mounted
2587          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2588          */
2589         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2590                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2591                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2592                                  "cannot be mounted RDWR without "
2593                                  "CONFIG_LBDAF");
2594                         return 0;
2595                 }
2596         }
2597         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2598             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2599                 ext4_msg(sb, KERN_ERR,
2600                          "Can't support bigalloc feature without "
2601                          "extents feature\n");
2602                 return 0;
2603         }
2604         return 1;
2605 }
2606
2607 /*
2608  * This function is called once a day if we have errors logged
2609  * on the file system
2610  */
2611 static void print_daily_error_info(unsigned long arg)
2612 {
2613         struct super_block *sb = (struct super_block *) arg;
2614         struct ext4_sb_info *sbi;
2615         struct ext4_super_block *es;
2616
2617         sbi = EXT4_SB(sb);
2618         es = sbi->s_es;
2619
2620         if (es->s_error_count)
2621                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2622                          le32_to_cpu(es->s_error_count));
2623         if (es->s_first_error_time) {
2624                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2625                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2626                        (int) sizeof(es->s_first_error_func),
2627                        es->s_first_error_func,
2628                        le32_to_cpu(es->s_first_error_line));
2629                 if (es->s_first_error_ino)
2630                         printk(": inode %u",
2631                                le32_to_cpu(es->s_first_error_ino));
2632                 if (es->s_first_error_block)
2633                         printk(": block %llu", (unsigned long long)
2634                                le64_to_cpu(es->s_first_error_block));
2635                 printk("\n");
2636         }
2637         if (es->s_last_error_time) {
2638                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2639                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2640                        (int) sizeof(es->s_last_error_func),
2641                        es->s_last_error_func,
2642                        le32_to_cpu(es->s_last_error_line));
2643                 if (es->s_last_error_ino)
2644                         printk(": inode %u",
2645                                le32_to_cpu(es->s_last_error_ino));
2646                 if (es->s_last_error_block)
2647                         printk(": block %llu", (unsigned long long)
2648                                le64_to_cpu(es->s_last_error_block));
2649                 printk("\n");
2650         }
2651         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2652 }
2653
2654 /* Find next suitable group and run ext4_init_inode_table */
2655 static int ext4_run_li_request(struct ext4_li_request *elr)
2656 {
2657         struct ext4_group_desc *gdp = NULL;
2658         ext4_group_t group, ngroups;
2659         struct super_block *sb;
2660         unsigned long timeout = 0;
2661         int ret = 0;
2662
2663         sb = elr->lr_super;
2664         ngroups = EXT4_SB(sb)->s_groups_count;
2665
2666         for (group = elr->lr_next_group; group < ngroups; group++) {
2667                 gdp = ext4_get_group_desc(sb, group, NULL);
2668                 if (!gdp) {
2669                         ret = 1;
2670                         break;
2671                 }
2672
2673                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2674                         break;
2675         }
2676
2677         if (group == ngroups)
2678                 ret = 1;
2679
2680         if (!ret) {
2681                 timeout = jiffies;
2682                 ret = ext4_init_inode_table(sb, group,
2683                                             elr->lr_timeout ? 0 : 1);
2684                 if (elr->lr_timeout == 0) {
2685                         timeout = (jiffies - timeout) *
2686                                   elr->lr_sbi->s_li_wait_mult;
2687                         elr->lr_timeout = timeout;
2688                 }
2689                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2690                 elr->lr_next_group = group + 1;
2691         }
2692
2693         return ret;
2694 }
2695
2696 /*
2697  * Remove lr_request from the list_request and free the
2698  * request structure. Should be called with li_list_mtx held
2699  */
2700 static void ext4_remove_li_request(struct ext4_li_request *elr)
2701 {
2702         struct ext4_sb_info *sbi;
2703
2704         if (!elr)
2705                 return;
2706
2707         sbi = elr->lr_sbi;
2708
2709         list_del(&elr->lr_request);
2710         sbi->s_li_request = NULL;
2711         kfree(elr);
2712 }
2713
2714 static void ext4_unregister_li_request(struct super_block *sb)
2715 {
2716         mutex_lock(&ext4_li_mtx);
2717         if (!ext4_li_info) {
2718                 mutex_unlock(&ext4_li_mtx);
2719                 return;
2720         }
2721
2722         mutex_lock(&ext4_li_info->li_list_mtx);
2723         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2724         mutex_unlock(&ext4_li_info->li_list_mtx);
2725         mutex_unlock(&ext4_li_mtx);
2726 }
2727
2728 static struct task_struct *ext4_lazyinit_task;
2729
2730 /*
2731  * This is the function where ext4lazyinit thread lives. It walks
2732  * through the request list searching for next scheduled filesystem.
2733  * When such a fs is found, run the lazy initialization request
2734  * (ext4_rn_li_request) and keep track of the time spend in this
2735  * function. Based on that time we compute next schedule time of
2736  * the request. When walking through the list is complete, compute
2737  * next waking time and put itself into sleep.
2738  */
2739 static int ext4_lazyinit_thread(void *arg)
2740 {
2741         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2742         struct list_head *pos, *n;
2743         struct ext4_li_request *elr;
2744         unsigned long next_wakeup, cur;
2745
2746         BUG_ON(NULL == eli);
2747
2748 cont_thread:
2749         while (true) {
2750                 next_wakeup = MAX_JIFFY_OFFSET;
2751
2752                 mutex_lock(&eli->li_list_mtx);
2753                 if (list_empty(&eli->li_request_list)) {
2754                         mutex_unlock(&eli->li_list_mtx);
2755                         goto exit_thread;
2756                 }
2757
2758                 list_for_each_safe(pos, n, &eli->li_request_list) {
2759                         elr = list_entry(pos, struct ext4_li_request,
2760                                          lr_request);
2761
2762                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2763                                 if (ext4_run_li_request(elr) != 0) {
2764                                         /* error, remove the lazy_init job */
2765                                         ext4_remove_li_request(elr);
2766                                         continue;
2767                                 }
2768                         }
2769
2770                         if (time_before(elr->lr_next_sched, next_wakeup))
2771                                 next_wakeup = elr->lr_next_sched;
2772                 }
2773                 mutex_unlock(&eli->li_list_mtx);
2774
2775                 try_to_freeze();
2776
2777                 cur = jiffies;
2778                 if ((time_after_eq(cur, next_wakeup)) ||
2779                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2780                         cond_resched();
2781                         continue;
2782                 }
2783
2784                 schedule_timeout_interruptible(next_wakeup - cur);
2785
2786                 if (kthread_should_stop()) {
2787                         ext4_clear_request_list();
2788                         goto exit_thread;
2789                 }
2790         }
2791
2792 exit_thread:
2793         /*
2794          * It looks like the request list is empty, but we need
2795          * to check it under the li_list_mtx lock, to prevent any
2796          * additions into it, and of course we should lock ext4_li_mtx
2797          * to atomically free the list and ext4_li_info, because at
2798          * this point another ext4 filesystem could be registering
2799          * new one.
2800          */
2801         mutex_lock(&ext4_li_mtx);
2802         mutex_lock(&eli->li_list_mtx);
2803         if (!list_empty(&eli->li_request_list)) {
2804                 mutex_unlock(&eli->li_list_mtx);
2805                 mutex_unlock(&ext4_li_mtx);
2806                 goto cont_thread;
2807         }
2808         mutex_unlock(&eli->li_list_mtx);
2809         kfree(ext4_li_info);
2810         ext4_li_info = NULL;
2811         mutex_unlock(&ext4_li_mtx);
2812
2813         return 0;
2814 }
2815
2816 static void ext4_clear_request_list(void)
2817 {
2818         struct list_head *pos, *n;
2819         struct ext4_li_request *elr;
2820
2821         mutex_lock(&ext4_li_info->li_list_mtx);
2822         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2823                 elr = list_entry(pos, struct ext4_li_request,
2824                                  lr_request);
2825                 ext4_remove_li_request(elr);
2826         }
2827         mutex_unlock(&ext4_li_info->li_list_mtx);
2828 }
2829
2830 static int ext4_run_lazyinit_thread(void)
2831 {
2832         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2833                                          ext4_li_info, "ext4lazyinit");
2834         if (IS_ERR(ext4_lazyinit_task)) {
2835                 int err = PTR_ERR(ext4_lazyinit_task);
2836                 ext4_clear_request_list();
2837                 kfree(ext4_li_info);
2838                 ext4_li_info = NULL;
2839                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
2840                                  "initialization thread\n",
2841                                  err);
2842                 return err;
2843         }
2844         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2845         return 0;
2846 }
2847
2848 /*
2849  * Check whether it make sense to run itable init. thread or not.
2850  * If there is at least one uninitialized inode table, return
2851  * corresponding group number, else the loop goes through all
2852  * groups and return total number of groups.
2853  */
2854 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2855 {
2856         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2857         struct ext4_group_desc *gdp = NULL;
2858
2859         for (group = 0; group < ngroups; group++) {
2860                 gdp = ext4_get_group_desc(sb, group, NULL);
2861                 if (!gdp)
2862                         continue;
2863
2864                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2865                         break;
2866         }
2867
2868         return group;
2869 }
2870
2871 static int ext4_li_info_new(void)
2872 {
2873         struct ext4_lazy_init *eli = NULL;
2874
2875         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2876         if (!eli)
2877                 return -ENOMEM;
2878
2879         INIT_LIST_HEAD(&eli->li_request_list);
2880         mutex_init(&eli->li_list_mtx);
2881
2882         eli->li_state |= EXT4_LAZYINIT_QUIT;
2883
2884         ext4_li_info = eli;
2885
2886         return 0;
2887 }
2888
2889 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2890                                             ext4_group_t start)
2891 {
2892         struct ext4_sb_info *sbi = EXT4_SB(sb);
2893         struct ext4_li_request *elr;
2894         unsigned long rnd;
2895
2896         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2897         if (!elr)
2898                 return NULL;
2899
2900         elr->lr_super = sb;
2901         elr->lr_sbi = sbi;
2902         elr->lr_next_group = start;
2903
2904         /*
2905          * Randomize first schedule time of the request to
2906          * spread the inode table initialization requests
2907          * better.
2908          */
2909         get_random_bytes(&rnd, sizeof(rnd));
2910         elr->lr_next_sched = jiffies + (unsigned long)rnd %
2911                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
2912
2913         return elr;
2914 }
2915
2916 static int ext4_register_li_request(struct super_block *sb,
2917                                     ext4_group_t first_not_zeroed)
2918 {
2919         struct ext4_sb_info *sbi = EXT4_SB(sb);
2920         struct ext4_li_request *elr;
2921         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2922         int ret = 0;
2923
2924         if (sbi->s_li_request != NULL) {
2925                 /*
2926                  * Reset timeout so it can be computed again, because
2927                  * s_li_wait_mult might have changed.
2928                  */
2929                 sbi->s_li_request->lr_timeout = 0;
2930                 return 0;
2931         }
2932
2933         if (first_not_zeroed == ngroups ||
2934             (sb->s_flags & MS_RDONLY) ||
2935             !test_opt(sb, INIT_INODE_TABLE))
2936                 return 0;
2937
2938         elr = ext4_li_request_new(sb, first_not_zeroed);
2939         if (!elr)
2940                 return -ENOMEM;
2941
2942         mutex_lock(&ext4_li_mtx);
2943
2944         if (NULL == ext4_li_info) {
2945                 ret = ext4_li_info_new();
2946                 if (ret)
2947                         goto out;
2948         }
2949
2950         mutex_lock(&ext4_li_info->li_list_mtx);
2951         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
2952         mutex_unlock(&ext4_li_info->li_list_mtx);
2953
2954         sbi->s_li_request = elr;
2955         /*
2956          * set elr to NULL here since it has been inserted to
2957          * the request_list and the removal and free of it is
2958          * handled by ext4_clear_request_list from now on.
2959          */
2960         elr = NULL;
2961
2962         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
2963                 ret = ext4_run_lazyinit_thread();
2964                 if (ret)
2965                         goto out;
2966         }
2967 out:
2968         mutex_unlock(&ext4_li_mtx);
2969         if (ret)
2970                 kfree(elr);
2971         return ret;
2972 }
2973
2974 /*
2975  * We do not need to lock anything since this is called on
2976  * module unload.
2977  */
2978 static void ext4_destroy_lazyinit_thread(void)
2979 {
2980         /*
2981          * If thread exited earlier
2982          * there's nothing to be done.
2983          */
2984         if (!ext4_li_info || !ext4_lazyinit_task)
2985                 return;
2986
2987         kthread_stop(ext4_lazyinit_task);
2988 }
2989
2990 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2991 {
2992         char *orig_data = kstrdup(data, GFP_KERNEL);
2993         struct buffer_head *bh;
2994         struct ext4_super_block *es = NULL;
2995         struct ext4_sb_info *sbi;
2996         ext4_fsblk_t block;
2997         ext4_fsblk_t sb_block = get_sb_block(&data);
2998         ext4_fsblk_t logical_sb_block;
2999         unsigned long offset = 0;
3000         unsigned long journal_devnum = 0;
3001         unsigned long def_mount_opts;
3002         struct inode *root;
3003         char *cp;
3004         const char *descr;
3005         int ret = -ENOMEM;
3006         int blocksize, clustersize;
3007         unsigned int db_count;
3008         unsigned int i;
3009         int needs_recovery, has_huge_files, has_bigalloc;
3010         __u64 blocks_count;
3011         int err;
3012         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3013         ext4_group_t first_not_zeroed;
3014
3015         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3016         if (!sbi)
3017                 goto out_free_orig;
3018
3019         sbi->s_blockgroup_lock =
3020                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3021         if (!sbi->s_blockgroup_lock) {
3022                 kfree(sbi);
3023                 goto out_free_orig;
3024         }
3025         sb->s_fs_info = sbi;
3026         sbi->s_mount_opt = 0;
3027         sbi->s_resuid = EXT4_DEF_RESUID;
3028         sbi->s_resgid = EXT4_DEF_RESGID;
3029         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3030         sbi->s_sb_block = sb_block;
3031         if (sb->s_bdev->bd_part)
3032                 sbi->s_sectors_written_start =
3033                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3034
3035         /* Cleanup superblock name */
3036         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3037                 *cp = '!';
3038
3039         ret = -EINVAL;
3040         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3041         if (!blocksize) {
3042                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3043                 goto out_fail;
3044         }
3045
3046         /*
3047          * The ext4 superblock will not be buffer aligned for other than 1kB
3048          * block sizes.  We need to calculate the offset from buffer start.
3049          */
3050         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3051                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3052                 offset = do_div(logical_sb_block, blocksize);
3053         } else {
3054                 logical_sb_block = sb_block;
3055         }
3056
3057         if (!(bh = sb_bread(sb, logical_sb_block))) {
3058                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3059                 goto out_fail;
3060         }
3061         /*
3062          * Note: s_es must be initialized as soon as possible because
3063          *       some ext4 macro-instructions depend on its value
3064          */
3065         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3066         sbi->s_es = es;
3067         sb->s_magic = le16_to_cpu(es->s_magic);
3068         if (sb->s_magic != EXT4_SUPER_MAGIC)
3069                 goto cantfind_ext4;
3070         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3071
3072         /* Check for a known checksum algorithm */
3073         if (!ext4_verify_csum_type(sb, es)) {
3074                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3075                          "unknown checksum algorithm.");
3076                 silent = 1;
3077                 goto cantfind_ext4;
3078         }
3079
3080         /* Load the checksum driver */
3081         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3082                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3083                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3084                 if (IS_ERR(sbi->s_chksum_driver)) {
3085                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3086                         ret = PTR_ERR(sbi->s_chksum_driver);
3087                         sbi->s_chksum_driver = NULL;
3088                         goto failed_mount;
3089                 }
3090         }
3091
3092         /* Check superblock checksum */
3093         if (!ext4_superblock_csum_verify(sb, es)) {
3094                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3095                          "invalid superblock checksum.  Run e2fsck?");
3096                 silent = 1;
3097                 goto cantfind_ext4;
3098         }
3099
3100         /* Precompute checksum seed for all metadata */
3101         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3102                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
3103                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3104                                                sizeof(es->s_uuid));
3105
3106         /* Set defaults before we parse the mount options */
3107         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3108         set_opt(sb, INIT_INODE_TABLE);
3109         if (def_mount_opts & EXT4_DEFM_DEBUG)
3110                 set_opt(sb, DEBUG);
3111         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3112                 set_opt(sb, GRPID);
3113         if (def_mount_opts & EXT4_DEFM_UID16)
3114                 set_opt(sb, NO_UID32);
3115         /* xattr user namespace & acls are now defaulted on */
3116 #ifdef CONFIG_EXT4_FS_XATTR
3117         set_opt(sb, XATTR_USER);
3118 #endif
3119 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3120         set_opt(sb, POSIX_ACL);
3121 #endif
3122         set_opt(sb, MBLK_IO_SUBMIT);
3123         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3124                 set_opt(sb, JOURNAL_DATA);
3125         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3126                 set_opt(sb, ORDERED_DATA);
3127         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3128                 set_opt(sb, WRITEBACK_DATA);
3129
3130         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3131                 set_opt(sb, ERRORS_PANIC);
3132         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3133                 set_opt(sb, ERRORS_CONT);
3134         else
3135                 set_opt(sb, ERRORS_RO);
3136         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3137                 set_opt(sb, BLOCK_VALIDITY);
3138         if (def_mount_opts & EXT4_DEFM_DISCARD)
3139                 set_opt(sb, DISCARD);
3140
3141         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
3142         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
3143         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3144         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3145         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3146
3147         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3148                 set_opt(sb, BARRIER);
3149
3150         /*
3151          * enable delayed allocation by default
3152          * Use -o nodelalloc to turn it off
3153          */
3154         if (!IS_EXT3_SB(sb) &&
3155             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3156                 set_opt(sb, DELALLOC);
3157
3158         /*
3159          * set default s_li_wait_mult for lazyinit, for the case there is
3160          * no mount option specified.
3161          */
3162         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3163
3164         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3165                            &journal_devnum, &journal_ioprio, 0)) {
3166                 ext4_msg(sb, KERN_WARNING,
3167                          "failed to parse options in superblock: %s",
3168                          sbi->s_es->s_mount_opts);
3169         }
3170         sbi->s_def_mount_opt = sbi->s_mount_opt;
3171         if (!parse_options((char *) data, sb, &journal_devnum,
3172                            &journal_ioprio, 0))
3173                 goto failed_mount;
3174
3175         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3176                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3177                             "with data=journal disables delayed "
3178                             "allocation and O_DIRECT support!\n");
3179                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3180                         ext4_msg(sb, KERN_ERR, "can't mount with "
3181                                  "both data=journal and delalloc");
3182                         goto failed_mount;
3183                 }
3184                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3185                         ext4_msg(sb, KERN_ERR, "can't mount with "
3186                                  "both data=journal and delalloc");
3187                         goto failed_mount;
3188                 }
3189                 if (test_opt(sb, DELALLOC))
3190                         clear_opt(sb, DELALLOC);
3191         }
3192
3193         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3194         if (test_opt(sb, DIOREAD_NOLOCK)) {
3195                 if (blocksize < PAGE_SIZE) {
3196                         ext4_msg(sb, KERN_ERR, "can't mount with "
3197                                  "dioread_nolock if block size != PAGE_SIZE");
3198                         goto failed_mount;
3199                 }
3200         }
3201
3202         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3203                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3204
3205         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3206             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3207              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3208              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3209                 ext4_msg(sb, KERN_WARNING,
3210                        "feature flags set on rev 0 fs, "
3211                        "running e2fsck is recommended");
3212
3213         if (IS_EXT2_SB(sb)) {
3214                 if (ext2_feature_set_ok(sb))
3215                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3216                                  "using the ext4 subsystem");
3217                 else {
3218                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3219                                  "to feature incompatibilities");
3220                         goto failed_mount;
3221                 }
3222         }
3223
3224         if (IS_EXT3_SB(sb)) {
3225                 if (ext3_feature_set_ok(sb))
3226                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3227                                  "using the ext4 subsystem");
3228                 else {
3229                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3230                                  "to feature incompatibilities");
3231                         goto failed_mount;
3232                 }
3233         }
3234
3235         /*
3236          * Check feature flags regardless of the revision level, since we
3237          * previously didn't change the revision level when setting the flags,
3238          * so there is a chance incompat flags are set on a rev 0 filesystem.
3239          */
3240         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3241                 goto failed_mount;
3242
3243         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3244             blocksize > EXT4_MAX_BLOCK_SIZE) {
3245                 ext4_msg(sb, KERN_ERR,
3246                        "Unsupported filesystem blocksize %d", blocksize);
3247                 goto failed_mount;
3248         }
3249
3250         if (sb->s_blocksize != blocksize) {
3251                 /* Validate the filesystem blocksize */
3252                 if (!sb_set_blocksize(sb, blocksize)) {
3253                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3254                                         blocksize);
3255                         goto failed_mount;
3256                 }
3257
3258                 brelse(bh);
3259                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3260                 offset = do_div(logical_sb_block, blocksize);
3261                 bh = sb_bread(sb, logical_sb_block);
3262                 if (!bh) {
3263                         ext4_msg(sb, KERN_ERR,
3264                                "Can't read superblock on 2nd try");
3265                         goto failed_mount;
3266                 }
3267                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
3268                 sbi->s_es = es;
3269                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3270                         ext4_msg(sb, KERN_ERR,
3271                                "Magic mismatch, very weird!");
3272                         goto failed_mount;
3273                 }
3274         }
3275
3276         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3277                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3278         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3279                                                       has_huge_files);
3280         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3281
3282         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3283                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3284                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3285         } else {
3286                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3287                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3288                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3289                     (!is_power_of_2(sbi->s_inode_size)) ||
3290                     (sbi->s_inode_size > blocksize)) {
3291                         ext4_msg(sb, KERN_ERR,
3292                                "unsupported inode size: %d",
3293                                sbi->s_inode_size);
3294                         goto failed_mount;
3295                 }
3296                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3297                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3298         }
3299
3300         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3301         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3302                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3303                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3304                     !is_power_of_2(sbi->s_desc_size)) {
3305                         ext4_msg(sb, KERN_ERR,
3306                                "unsupported descriptor size %lu",
3307                                sbi->s_desc_size);
3308                         goto failed_mount;
3309                 }
3310         } else
3311                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3312
3313         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3314         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3315         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3316                 goto cantfind_ext4;
3317
3318         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3319         if (sbi->s_inodes_per_block == 0)
3320                 goto cantfind_ext4;
3321         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3322                                         sbi->s_inodes_per_block;
3323         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3324         sbi->s_sbh = bh;
3325         sbi->s_mount_state = le16_to_cpu(es->s_state);
3326         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3327         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3328
3329         for (i = 0; i < 4; i++)
3330                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3331         sbi->s_def_hash_version = es->s_def_hash_version;
3332         i = le32_to_cpu(es->s_flags);
3333         if (i & EXT2_FLAGS_UNSIGNED_HASH)
3334                 sbi->s_hash_unsigned = 3;
3335         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3336 #ifdef __CHAR_UNSIGNED__
3337                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3338                 sbi->s_hash_unsigned = 3;
3339 #else
3340                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3341 #endif
3342         }
3343
3344         /* Handle clustersize */
3345         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3346         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3347                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3348         if (has_bigalloc) {
3349                 if (clustersize < blocksize) {
3350                         ext4_msg(sb, KERN_ERR,
3351                                  "cluster size (%d) smaller than "
3352                                  "block size (%d)", clustersize, blocksize);
3353                         goto failed_mount;
3354                 }
3355                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3356                         le32_to_cpu(es->s_log_block_size);
3357                 sbi->s_clusters_per_group =
3358                         le32_to_cpu(es->s_clusters_per_group);
3359                 if (sbi->s_clusters_per_group > blocksize * 8) {
3360                         ext4_msg(sb, KERN_ERR,
3361                                  "#clusters per group too big: %lu",
3362                                  sbi->s_clusters_per_group);
3363                         goto failed_mount;
3364                 }
3365                 if (sbi->s_blocks_per_group !=
3366                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3367                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3368                                  "clusters per group (%lu) inconsistent",
3369                                  sbi->s_blocks_per_group,
3370                                  sbi->s_clusters_per_group);
3371                         goto failed_mount;
3372                 }
3373         } else {
3374                 if (clustersize != blocksize) {
3375                         ext4_warning(sb, "fragment/cluster size (%d) != "
3376                                      "block size (%d)", clustersize,
3377                                      blocksize);
3378                         clustersize = blocksize;
3379                 }
3380                 if (sbi->s_blocks_per_group > blocksize * 8) {
3381                         ext4_msg(sb, KERN_ERR,
3382                                  "#blocks per group too big: %lu",
3383                                  sbi->s_blocks_per_group);
3384                         goto failed_mount;
3385                 }
3386                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3387                 sbi->s_cluster_bits = 0;
3388         }
3389         sbi->s_cluster_ratio = clustersize / blocksize;
3390
3391         if (sbi->s_inodes_per_group > blocksize * 8) {
3392                 ext4_msg(sb, KERN_ERR,
3393                        "#inodes per group too big: %lu",
3394                        sbi->s_inodes_per_group);
3395                 goto failed_mount;
3396         }
3397
3398         /*
3399          * Test whether we have more sectors than will fit in sector_t,
3400          * and whether the max offset is addressable by the page cache.
3401          */
3402         err = generic_check_addressable(sb->s_blocksize_bits,
3403                                         ext4_blocks_count(es));
3404         if (err) {
3405                 ext4_msg(sb, KERN_ERR, "filesystem"
3406                          " too large to mount safely on this system");
3407                 if (sizeof(sector_t) < 8)
3408                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3409                 ret = err;
3410                 goto failed_mount;
3411         }
3412
3413         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3414                 goto cantfind_ext4;
3415
3416         /* check blocks count against device size */
3417         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3418         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3419                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3420                        "exceeds size of device (%llu blocks)",
3421                        ext4_blocks_count(es), blocks_count);
3422                 goto failed_mount;
3423         }
3424
3425         /*
3426          * It makes no sense for the first data block to be beyond the end
3427          * of the filesystem.
3428          */
3429         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3430                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3431                          "block %u is beyond end of filesystem (%llu)",
3432                          le32_to_cpu(es->s_first_data_block),
3433                          ext4_blocks_count(es));
3434                 goto failed_mount;
3435         }
3436         blocks_count = (ext4_blocks_count(es) -
3437                         le32_to_cpu(es->s_first_data_block) +
3438                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3439         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3440         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3441                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3442                        "(block count %llu, first data block %u, "
3443                        "blocks per group %lu)", sbi->s_groups_count,
3444                        ext4_blocks_count(es),
3445                        le32_to_cpu(es->s_first_data_block),
3446                        EXT4_BLOCKS_PER_GROUP(sb));
3447                 goto failed_mount;
3448         }
3449         sbi->s_groups_count = blocks_count;
3450         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3451                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3452         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3453                    EXT4_DESC_PER_BLOCK(sb);
3454         sbi->s_group_desc = ext4_kvmalloc(db_count *
3455                                           sizeof(struct buffer_head *),
3456                                           GFP_KERNEL);
3457         if (sbi->s_group_desc == NULL) {
3458                 ext4_msg(sb, KERN_ERR, "not enough memory");
3459                 goto failed_mount;
3460         }
3461
3462         if (ext4_proc_root)
3463                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3464
3465         if (sbi->s_proc)
3466                 proc_create_data("options", S_IRUGO, sbi->s_proc,
3467                                  &ext4_seq_options_fops, sb);
3468
3469         bgl_lock_init(sbi->s_blockgroup_lock);
3470
3471         for (i = 0; i < db_count; i++) {
3472                 block = descriptor_loc(sb, logical_sb_block, i);
3473                 sbi->s_group_desc[i] = sb_bread(sb, block);
3474                 if (!sbi->s_group_desc[i]) {
3475                         ext4_msg(sb, KERN_ERR,
3476                                "can't read group descriptor %d", i);
3477                         db_count = i;
3478                         goto failed_mount2;
3479                 }
3480         }
3481         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3482                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3483                 goto failed_mount2;
3484         }
3485         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3486                 if (!ext4_fill_flex_info(sb)) {
3487                         ext4_msg(sb, KERN_ERR,
3488                                "unable to initialize "
3489                                "flex_bg meta info!");
3490                         goto failed_mount2;
3491                 }
3492
3493         sbi->s_gdb_count = db_count;
3494         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3495         spin_lock_init(&sbi->s_next_gen_lock);
3496
3497         init_timer(&sbi->s_err_report);
3498         sbi->s_err_report.function = print_daily_error_info;
3499         sbi->s_err_report.data = (unsigned long) sb;
3500
3501         err = percpu_counter_init(&sbi->s_freeclusters_counter,
3502                         ext4_count_free_clusters(sb));
3503         if (!err) {
3504                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
3505                                 ext4_count_free_inodes(sb));
3506         }
3507         if (!err) {
3508                 err = percpu_counter_init(&sbi->s_dirs_counter,
3509                                 ext4_count_dirs(sb));
3510         }
3511         if (!err) {
3512                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0);
3513         }
3514         if (err) {
3515                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3516                 goto failed_mount3;
3517         }
3518
3519         sbi->s_stripe = ext4_get_stripe_size(sbi);
3520         sbi->s_max_writeback_mb_bump = 128;
3521
3522         /*
3523          * set up enough so that it can read an inode
3524          */
3525         if (!test_opt(sb, NOLOAD) &&
3526             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3527                 sb->s_op = &ext4_sops;
3528         else
3529                 sb->s_op = &ext4_nojournal_sops;
3530         sb->s_export_op = &ext4_export_ops;
3531         sb->s_xattr = ext4_xattr_handlers;
3532 #ifdef CONFIG_QUOTA
3533         sb->s_qcop = &ext4_qctl_operations;
3534         sb->dq_op = &ext4_quota_operations;
3535 #endif
3536         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3537
3538         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3539         mutex_init(&sbi->s_orphan_lock);
3540         sbi->s_resize_flags = 0;
3541
3542         sb->s_root = NULL;
3543
3544         needs_recovery = (es->s_last_orphan != 0 ||
3545                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3546                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3547
3548         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3549             !(sb->s_flags & MS_RDONLY))
3550                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3551                         goto failed_mount3;
3552
3553         /*
3554          * The first inode we look at is the journal inode.  Don't try
3555          * root first: it may be modified in the journal!
3556          */
3557         if (!test_opt(sb, NOLOAD) &&
3558             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3559                 if (ext4_load_journal(sb, es, journal_devnum))
3560                         goto failed_mount3;
3561         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3562               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3563                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3564                        "suppressed and not mounted read-only");
3565                 goto failed_mount_wq;
3566         } else {
3567                 clear_opt(sb, DATA_FLAGS);
3568                 sbi->s_journal = NULL;
3569                 needs_recovery = 0;
3570                 goto no_journal;
3571         }
3572
3573         if (ext4_blocks_count(es) > 0xffffffffULL &&
3574             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3575                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3576                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3577                 goto failed_mount_wq;
3578         }
3579
3580         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3581                 jbd2_journal_set_features(sbi->s_journal,
3582                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3583                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3584         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3585                 jbd2_journal_set_features(sbi->s_journal,
3586                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
3587                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3588                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3589         } else {
3590                 jbd2_journal_clear_features(sbi->s_journal,
3591                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3592                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3593         }
3594
3595         /* We have now updated the journal if required, so we can
3596          * validate the data journaling mode. */
3597         switch (test_opt(sb, DATA_FLAGS)) {
3598         case 0:
3599                 /* No mode set, assume a default based on the journal
3600                  * capabilities: ORDERED_DATA if the journal can
3601                  * cope, else JOURNAL_DATA
3602                  */
3603                 if (jbd2_journal_check_available_features
3604                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3605                         set_opt(sb, ORDERED_DATA);
3606                 else
3607                         set_opt(sb, JOURNAL_DATA);
3608                 break;
3609
3610         case EXT4_MOUNT_ORDERED_DATA:
3611         case EXT4_MOUNT_WRITEBACK_DATA:
3612                 if (!jbd2_journal_check_available_features
3613                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3614                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3615                                "requested data journaling mode");
3616                         goto failed_mount_wq;
3617                 }
3618         default:
3619                 break;
3620         }
3621         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3622
3623         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
3624
3625         /*
3626          * The journal may have updated the bg summary counts, so we
3627          * need to update the global counters.
3628          */
3629         percpu_counter_set(&sbi->s_freeclusters_counter,
3630                            ext4_count_free_clusters(sb));
3631         percpu_counter_set(&sbi->s_freeinodes_counter,
3632                            ext4_count_free_inodes(sb));
3633         percpu_counter_set(&sbi->s_dirs_counter,
3634                            ext4_count_dirs(sb));
3635         percpu_counter_set(&sbi->s_dirtyclusters_counter, 0);
3636
3637 no_journal:
3638         /*
3639          * The maximum number of concurrent works can be high and
3640          * concurrency isn't really necessary.  Limit it to 1.
3641          */
3642         EXT4_SB(sb)->dio_unwritten_wq =
3643                 alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
3644         if (!EXT4_SB(sb)->dio_unwritten_wq) {
3645                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
3646                 goto failed_mount_wq;
3647         }
3648
3649         /*
3650          * The jbd2_journal_load will have done any necessary log recovery,
3651          * so we can safely mount the rest of the filesystem now.
3652          */
3653
3654         root = ext4_iget(sb, EXT4_ROOT_INO);
3655         if (IS_ERR(root)) {
3656                 ext4_msg(sb, KERN_ERR, "get root inode failed");
3657                 ret = PTR_ERR(root);
3658                 root = NULL;
3659                 goto failed_mount4;
3660         }
3661         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3662                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3663                 iput(root);
3664                 goto failed_mount4;
3665         }
3666         sb->s_root = d_make_root(root);
3667         if (!sb->s_root) {
3668                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
3669                 ret = -ENOMEM;
3670                 goto failed_mount4;
3671         }
3672
3673         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
3674
3675         /* determine the minimum size of new large inodes, if present */
3676         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3677                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3678                                                      EXT4_GOOD_OLD_INODE_SIZE;
3679                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3680                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
3681                         if (sbi->s_want_extra_isize <
3682                             le16_to_cpu(es->s_want_extra_isize))
3683                                 sbi->s_want_extra_isize =
3684                                         le16_to_cpu(es->s_want_extra_isize);
3685                         if (sbi->s_want_extra_isize <
3686                             le16_to_cpu(es->s_min_extra_isize))
3687                                 sbi->s_want_extra_isize =
3688                                         le16_to_cpu(es->s_min_extra_isize);
3689                 }
3690         }
3691         /* Check if enough inode space is available */
3692         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3693                                                         sbi->s_inode_size) {
3694                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3695                                                        EXT4_GOOD_OLD_INODE_SIZE;
3696                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
3697                          "available");
3698         }
3699
3700         err = ext4_setup_system_zone(sb);
3701         if (err) {
3702                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3703                          "zone (%d)", err);
3704                 goto failed_mount4a;
3705         }
3706
3707         ext4_ext_init(sb);
3708         err = ext4_mb_init(sb, needs_recovery);
3709         if (err) {
3710                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3711                          err);
3712                 goto failed_mount5;
3713         }
3714
3715         err = ext4_register_li_request(sb, first_not_zeroed);
3716         if (err)
3717                 goto failed_mount6;
3718
3719         sbi->s_kobj.kset = ext4_kset;
3720         init_completion(&sbi->s_kobj_unregister);
3721         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3722                                    "%s", sb->s_id);
3723         if (err)
3724                 goto failed_mount7;
3725
3726         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3727         ext4_orphan_cleanup(sb, es);
3728         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3729         if (needs_recovery) {
3730                 ext4_msg(sb, KERN_INFO, "recovery complete");
3731                 ext4_mark_recovery_complete(sb, es);
3732         }
3733         if (EXT4_SB(sb)->s_journal) {
3734                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3735                         descr = " journalled data mode";
3736                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3737                         descr = " ordered data mode";
3738                 else
3739                         descr = " writeback data mode";
3740         } else
3741                 descr = "out journal";
3742
3743         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3744                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
3745                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
3746
3747         if (es->s_error_count)
3748                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
3749
3750         kfree(orig_data);
3751         return 0;
3752
3753 cantfind_ext4:
3754         if (!silent)
3755                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3756         goto failed_mount;
3757
3758 failed_mount7:
3759         ext4_unregister_li_request(sb);
3760 failed_mount6:
3761         ext4_mb_release(sb);
3762 failed_mount5:
3763         ext4_ext_release(sb);
3764         ext4_release_system_zone(sb);
3765 failed_mount4a:
3766         dput(sb->s_root);
3767         sb->s_root = NULL;
3768 failed_mount4:
3769         ext4_msg(sb, KERN_ERR, "mount failed");
3770         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
3771 failed_mount_wq:
3772         if (sbi->s_journal) {
3773                 jbd2_journal_destroy(sbi->s_journal);
3774                 sbi->s_journal = NULL;
3775         }
3776 failed_mount3:
3777         del_timer(&sbi->s_err_report);
3778         if (sbi->s_flex_groups)
3779                 ext4_kvfree(sbi->s_flex_groups);
3780         percpu_counter_destroy(&sbi->s_freeclusters_counter);
3781         percpu_counter_destroy(&sbi->s_freeinodes_counter);
3782         percpu_counter_destroy(&sbi->s_dirs_counter);
3783         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
3784         if (sbi->s_mmp_tsk)
3785                 kthread_stop(sbi->s_mmp_tsk);
3786 failed_mount2:
3787         for (i = 0; i < db_count; i++)
3788                 brelse(sbi->s_group_desc[i]);
3789         ext4_kvfree(sbi->s_group_desc);
3790 failed_mount:
3791         if (sbi->s_chksum_driver)
3792                 crypto_free_shash(sbi->s_chksum_driver);
3793         if (sbi->s_proc) {
3794                 remove_proc_entry("options", sbi->s_proc);
3795                 remove_proc_entry(sb->s_id, ext4_proc_root);
3796         }
3797 #ifdef CONFIG_QUOTA
3798         for (i = 0; i < MAXQUOTAS; i++)
3799                 kfree(sbi->s_qf_names[i]);
3800 #endif
3801         ext4_blkdev_remove(sbi);
3802         brelse(bh);
3803 out_fail:
3804         sb->s_fs_info = NULL;
3805         kfree(sbi->s_blockgroup_lock);
3806         kfree(sbi);
3807 out_free_orig:
3808         kfree(orig_data);
3809         return ret;
3810 }
3811
3812 /*
3813  * Setup any per-fs journal parameters now.  We'll do this both on
3814  * initial mount, once the journal has been initialised but before we've
3815  * done any recovery; and again on any subsequent remount.
3816  */
3817 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
3818 {
3819         struct ext4_sb_info *sbi = EXT4_SB(sb);
3820
3821         journal->j_commit_interval = sbi->s_commit_interval;
3822         journal->j_min_batch_time = sbi->s_min_batch_time;
3823         journal->j_max_batch_time = sbi->s_max_batch_time;
3824
3825         write_lock(&journal->j_state_lock);
3826         if (test_opt(sb, BARRIER))
3827                 journal->j_flags |= JBD2_BARRIER;
3828         else
3829                 journal->j_flags &= ~JBD2_BARRIER;
3830         if (test_opt(sb, DATA_ERR_ABORT))
3831                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3832         else
3833                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3834         write_unlock(&journal->j_state_lock);
3835 }
3836
3837 static journal_t *ext4_get_journal(struct super_block *sb,
3838                                    unsigned int journal_inum)
3839 {
3840         struct inode *journal_inode;
3841         journal_t *journal;
3842
3843         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3844
3845         /* First, test for the existence of a valid inode on disk.  Bad
3846          * things happen if we iget() an unused inode, as the subsequent
3847          * iput() will try to delete it. */
3848
3849         journal_inode = ext4_iget(sb, journal_inum);
3850         if (IS_ERR(journal_inode)) {
3851                 ext4_msg(sb, KERN_ERR, "no journal found");
3852                 return NULL;
3853         }
3854         if (!journal_inode->i_nlink) {
3855                 make_bad_inode(journal_inode);
3856                 iput(journal_inode);
3857                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3858                 return NULL;
3859         }
3860
3861         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3862                   journal_inode, journal_inode->i_size);
3863         if (!S_ISREG(journal_inode->i_mode)) {
3864                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3865                 iput(journal_inode);
3866                 return NULL;
3867         }
3868
3869         journal = jbd2_journal_init_inode(journal_inode);
3870         if (!journal) {
3871                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3872                 iput(journal_inode);
3873                 return NULL;
3874         }
3875         journal->j_private = sb;
3876         ext4_init_journal_params(sb, journal);
3877         return journal;
3878 }
3879
3880 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3881                                        dev_t j_dev)
3882 {
3883         struct buffer_head *bh;
3884         journal_t *journal;
3885         ext4_fsblk_t start;
3886         ext4_fsblk_t len;
3887         int hblock, blocksize;
3888         ext4_fsblk_t sb_block;
3889         unsigned long offset;
3890         struct ext4_super_block *es;
3891         struct block_device *bdev;
3892
3893         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3894
3895         bdev = ext4_blkdev_get(j_dev, sb);
3896         if (bdev == NULL)
3897                 return NULL;
3898
3899         blocksize = sb->s_blocksize;
3900         hblock = bdev_logical_block_size(bdev);
3901         if (blocksize < hblock) {
3902                 ext4_msg(sb, KERN_ERR,
3903                         "blocksize too small for journal device");
3904                 goto out_bdev;
3905         }
3906
3907         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3908         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3909         set_blocksize(bdev, blocksize);
3910         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3911                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3912                        "external journal");
3913                 goto out_bdev;
3914         }
3915
3916         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3917         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3918             !(le32_to_cpu(es->s_feature_incompat) &
3919               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3920                 ext4_msg(sb, KERN_ERR, "external journal has "
3921                                         "bad superblock");
3922                 brelse(bh);
3923                 goto out_bdev;
3924         }
3925
3926         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3927                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3928                 brelse(bh);
3929                 goto out_bdev;
3930         }
3931
3932         len = ext4_blocks_count(es);
3933         start = sb_block + 1;
3934         brelse(bh);     /* we're done with the superblock */
3935
3936         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3937                                         start, len, blocksize);
3938         if (!journal) {
3939                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3940                 goto out_bdev;
3941         }
3942         journal->j_private = sb;
3943         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3944         wait_on_buffer(journal->j_sb_buffer);
3945         if (!buffer_uptodate(journal->j_sb_buffer)) {
3946                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3947                 goto out_journal;
3948         }
3949         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3950                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3951                                         "user (unsupported) - %d",
3952                         be32_to_cpu(journal->j_superblock->s_nr_users));
3953                 goto out_journal;
3954         }
3955         EXT4_SB(sb)->journal_bdev = bdev;
3956         ext4_init_journal_params(sb, journal);
3957         return journal;
3958
3959 out_journal:
3960         jbd2_journal_destroy(journal);
3961 out_bdev:
3962         ext4_blkdev_put(bdev);
3963         return NULL;
3964 }
3965
3966 static int ext4_load_journal(struct super_block *sb,
3967                              struct ext4_super_block *es,
3968                              unsigned long journal_devnum)
3969 {
3970         journal_t *journal;
3971         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3972         dev_t journal_dev;
3973         int err = 0;
3974         int really_read_only;
3975
3976         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3977
3978         if (journal_devnum &&
3979             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3980                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3981                         "numbers have changed");
3982                 journal_dev = new_decode_dev(journal_devnum);
3983         } else
3984                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3985
3986         really_read_only = bdev_read_only(sb->s_bdev);
3987
3988         /*
3989          * Are we loading a blank journal or performing recovery after a
3990          * crash?  For recovery, we need to check in advance whether we
3991          * can get read-write access to the device.
3992          */
3993         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3994                 if (sb->s_flags & MS_RDONLY) {
3995                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3996                                         "required on readonly filesystem");
3997                         if (really_read_only) {
3998                                 ext4_msg(sb, KERN_ERR, "write access "
3999                                         "unavailable, cannot proceed");
4000                                 return -EROFS;
4001                         }
4002                         ext4_msg(sb, KERN_INFO, "write access will "
4003                                "be enabled during recovery");
4004                 }
4005         }
4006
4007         if (journal_inum && journal_dev) {
4008                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4009                        "and inode journals!");
4010                 return -EINVAL;
4011         }
4012
4013         if (journal_inum) {
4014                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4015                         return -EINVAL;
4016         } else {
4017                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4018                         return -EINVAL;
4019         }
4020
4021         if (!(journal->j_flags & JBD2_BARRIER))
4022                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4023
4024         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4025                 err = jbd2_journal_wipe(journal, !really_read_only);
4026         if (!err) {
4027                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4028                 if (save)
4029                         memcpy(save, ((char *) es) +
4030                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4031                 err = jbd2_journal_load(journal);
4032                 if (save)
4033                         memcpy(((char *) es) + EXT4_S_ERR_START,
4034                                save, EXT4_S_ERR_LEN);
4035                 kfree(save);
4036         }
4037
4038         if (err) {
4039                 ext4_msg(sb, KERN_ERR, "error loading journal");
4040                 jbd2_journal_destroy(journal);
4041                 return err;
4042         }
4043
4044         EXT4_SB(sb)->s_journal = journal;
4045         ext4_clear_journal_err(sb, es);
4046
4047         if (!really_read_only && journal_devnum &&
4048             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4049                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4050
4051                 /* Make sure we flush the recovery flag to disk. */
4052                 ext4_commit_super(sb, 1);
4053         }
4054
4055         return 0;
4056 }
4057
4058 static int ext4_commit_super(struct super_block *sb, int sync)
4059 {
4060         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4061         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4062         int error = 0;
4063
4064         if (!sbh || block_device_ejected(sb))
4065                 return error;
4066         if (buffer_write_io_error(sbh)) {
4067                 /*
4068                  * Oh, dear.  A previous attempt to write the
4069                  * superblock failed.  This could happen because the
4070                  * USB device was yanked out.  Or it could happen to
4071                  * be a transient write error and maybe the block will
4072                  * be remapped.  Nothing we can do but to retry the
4073                  * write and hope for the best.
4074                  */
4075                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4076                        "superblock detected");
4077                 clear_buffer_write_io_error(sbh);
4078                 set_buffer_uptodate(sbh);
4079         }
4080         /*
4081          * If the file system is mounted read-only, don't update the
4082          * superblock write time.  This avoids updating the superblock
4083          * write time when we are mounting the root file system
4084          * read/only but we need to replay the journal; at that point,
4085          * for people who are east of GMT and who make their clock
4086          * tick in localtime for Windows bug-for-bug compatibility,
4087          * the clock is set in the future, and this will cause e2fsck
4088          * to complain and force a full file system check.
4089          */
4090         if (!(sb->s_flags & MS_RDONLY))
4091                 es->s_wtime = cpu_to_le32(get_seconds());
4092         if (sb->s_bdev->bd_part)
4093                 es->s_kbytes_written =
4094                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4095                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4096                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4097         else
4098                 es->s_kbytes_written =
4099                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4100         ext4_free_blocks_count_set(es,
4101                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4102                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4103         es->s_free_inodes_count =
4104                 cpu_to_le32(percpu_counter_sum_positive(
4105                                 &EXT4_SB(sb)->s_freeinodes_counter));
4106         sb->s_dirt = 0;
4107         BUFFER_TRACE(sbh, "marking dirty");
4108         ext4_superblock_csum_set(sb, es);
4109         mark_buffer_dirty(sbh);
4110         if (sync) {
4111                 error = sync_dirty_buffer(sbh);
4112                 if (error)
4113                         return error;
4114
4115                 error = buffer_write_io_error(sbh);
4116                 if (error) {
4117                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4118                                "superblock");
4119                         clear_buffer_write_io_error(sbh);
4120                         set_buffer_uptodate(sbh);
4121                 }
4122         }
4123         return error;
4124 }
4125
4126 /*
4127  * Have we just finished recovery?  If so, and if we are mounting (or
4128  * remounting) the filesystem readonly, then we will end up with a
4129  * consistent fs on disk.  Record that fact.
4130  */
4131 static void ext4_mark_recovery_complete(struct super_block *sb,
4132                                         struct ext4_super_block *es)
4133 {
4134         journal_t *journal = EXT4_SB(sb)->s_journal;
4135
4136         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4137                 BUG_ON(journal != NULL);
4138                 return;
4139         }
4140         jbd2_journal_lock_updates(journal);
4141         if (jbd2_journal_flush(journal) < 0)
4142                 goto out;
4143
4144         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4145             sb->s_flags & MS_RDONLY) {
4146                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4147                 ext4_commit_super(sb, 1);
4148         }
4149
4150 out:
4151         jbd2_journal_unlock_updates(journal);
4152 }
4153
4154 /*
4155  * If we are mounting (or read-write remounting) a filesystem whose journal
4156  * has recorded an error from a previous lifetime, move that error to the
4157  * main filesystem now.
4158  */
4159 static void ext4_clear_journal_err(struct super_block *sb,
4160                                    struct ext4_super_block *es)
4161 {
4162         journal_t *journal;
4163         int j_errno;
4164         const char *errstr;
4165
4166         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4167
4168         journal = EXT4_SB(sb)->s_journal;
4169
4170         /*
4171          * Now check for any error status which may have been recorded in the
4172          * journal by a prior ext4_error() or ext4_abort()
4173          */
4174
4175         j_errno = jbd2_journal_errno(journal);
4176         if (j_errno) {
4177                 char nbuf[16];
4178
4179                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4180                 ext4_warning(sb, "Filesystem error recorded "
4181                              "from previous mount: %s", errstr);
4182                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4183
4184                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4185                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4186                 ext4_commit_super(sb, 1);
4187
4188                 jbd2_journal_clear_err(journal);
4189         }
4190 }
4191
4192 /*
4193  * Force the running and committing transactions to commit,
4194  * and wait on the commit.
4195  */
4196 int ext4_force_commit(struct super_block *sb)
4197 {
4198         journal_t *journal;
4199         int ret = 0;
4200
4201         if (sb->s_flags & MS_RDONLY)
4202                 return 0;
4203
4204         journal = EXT4_SB(sb)->s_journal;
4205         if (journal) {
4206                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
4207                 ret = ext4_journal_force_commit(journal);
4208         }
4209
4210         return ret;
4211 }
4212
4213 static void ext4_write_super(struct super_block *sb)
4214 {
4215         lock_super(sb);
4216         ext4_commit_super(sb, 1);
4217         unlock_super(sb);
4218 }
4219
4220 static int ext4_sync_fs(struct super_block *sb, int wait)
4221 {
4222         int ret = 0;
4223         tid_t target;
4224         struct ext4_sb_info *sbi = EXT4_SB(sb);
4225
4226         trace_ext4_sync_fs(sb, wait);
4227         flush_workqueue(sbi->dio_unwritten_wq);
4228         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4229                 if (wait)
4230                         jbd2_log_wait_commit(sbi->s_journal, target);
4231         }
4232         return ret;
4233 }
4234
4235 /*
4236  * LVM calls this function before a (read-only) snapshot is created.  This
4237  * gives us a chance to flush the journal completely and mark the fs clean.
4238  *
4239  * Note that only this function cannot bring a filesystem to be in a clean
4240  * state independently, because ext4 prevents a new handle from being started
4241  * by @sb->s_frozen, which stays in an upper layer.  It thus needs help from
4242  * the upper layer.
4243  */
4244 static int ext4_freeze(struct super_block *sb)
4245 {
4246         int error = 0;
4247         journal_t *journal;
4248
4249         if (sb->s_flags & MS_RDONLY)
4250                 return 0;
4251
4252         journal = EXT4_SB(sb)->s_journal;
4253
4254         /* Now we set up the journal barrier. */
4255         jbd2_journal_lock_updates(journal);
4256
4257         /*
4258          * Don't clear the needs_recovery flag if we failed to flush
4259          * the journal.
4260          */
4261         error = jbd2_journal_flush(journal);
4262         if (error < 0)
4263                 goto out;
4264
4265         /* Journal blocked and flushed, clear needs_recovery flag. */
4266         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4267         error = ext4_commit_super(sb, 1);
4268 out:
4269         /* we rely on s_frozen to stop further updates */
4270         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4271         return error;
4272 }
4273
4274 /*
4275  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4276  * flag here, even though the filesystem is not technically dirty yet.
4277  */
4278 static int ext4_unfreeze(struct super_block *sb)
4279 {
4280         if (sb->s_flags & MS_RDONLY)
4281                 return 0;
4282
4283         lock_super(sb);
4284         /* Reset the needs_recovery flag before the fs is unlocked. */
4285         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4286         ext4_commit_super(sb, 1);
4287         unlock_super(sb);
4288         return 0;
4289 }
4290
4291 /*
4292  * Structure to save mount options for ext4_remount's benefit
4293  */
4294 struct ext4_mount_options {
4295         unsigned long s_mount_opt;
4296         unsigned long s_mount_opt2;
4297         uid_t s_resuid;
4298         gid_t s_resgid;
4299         unsigned long s_commit_interval;
4300         u32 s_min_batch_time, s_max_batch_time;
4301 #ifdef CONFIG_QUOTA
4302         int s_jquota_fmt;
4303         char *s_qf_names[MAXQUOTAS];
4304 #endif
4305 };
4306
4307 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4308 {
4309         struct ext4_super_block *es;
4310         struct ext4_sb_info *sbi = EXT4_SB(sb);
4311         unsigned long old_sb_flags;
4312         struct ext4_mount_options old_opts;
4313         int enable_quota = 0;
4314         ext4_group_t g;
4315         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4316         int err = 0;
4317 #ifdef CONFIG_QUOTA
4318         int i;
4319 #endif
4320         char *orig_data = kstrdup(data, GFP_KERNEL);
4321
4322         /* Store the original options */
4323         lock_super(sb);
4324         old_sb_flags = sb->s_flags;
4325         old_opts.s_mount_opt = sbi->s_mount_opt;
4326         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4327         old_opts.s_resuid = sbi->s_resuid;
4328         old_opts.s_resgid = sbi->s_resgid;
4329         old_opts.s_commit_interval = sbi->s_commit_interval;
4330         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4331         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4332 #ifdef CONFIG_QUOTA
4333         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4334         for (i = 0; i < MAXQUOTAS; i++)
4335                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
4336 #endif
4337         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4338                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4339
4340         /*
4341          * Allow the "check" option to be passed as a remount option.
4342          */
4343         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4344                 err = -EINVAL;
4345                 goto restore_opts;
4346         }
4347
4348         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4349                 ext4_abort(sb, "Abort forced by user");
4350
4351         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4352                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4353
4354         es = sbi->s_es;
4355
4356         if (sbi->s_journal) {
4357                 ext4_init_journal_params(sb, sbi->s_journal);
4358                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4359         }
4360
4361         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4362                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4363                         err = -EROFS;
4364                         goto restore_opts;
4365                 }
4366
4367                 if (*flags & MS_RDONLY) {
4368                         err = dquot_suspend(sb, -1);
4369                         if (err < 0)
4370                                 goto restore_opts;
4371
4372                         /*
4373                          * First of all, the unconditional stuff we have to do
4374                          * to disable replay of the journal when we next remount
4375                          */
4376                         sb->s_flags |= MS_RDONLY;
4377
4378                         /*
4379                          * OK, test if we are remounting a valid rw partition
4380                          * readonly, and if so set the rdonly flag and then
4381                          * mark the partition as valid again.
4382                          */
4383                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4384                             (sbi->s_mount_state & EXT4_VALID_FS))
4385                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4386
4387                         if (sbi->s_journal)
4388                                 ext4_mark_recovery_complete(sb, es);
4389                 } else {
4390                         /* Make sure we can mount this feature set readwrite */
4391                         if (!ext4_feature_set_ok(sb, 0)) {
4392                                 err = -EROFS;
4393                                 goto restore_opts;
4394                         }
4395                         /*
4396                          * Make sure the group descriptor checksums
4397                          * are sane.  If they aren't, refuse to remount r/w.
4398                          */
4399                         for (g = 0; g < sbi->s_groups_count; g++) {
4400                                 struct ext4_group_desc *gdp =
4401                                         ext4_get_group_desc(sb, g, NULL);
4402
4403                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
4404                                         ext4_msg(sb, KERN_ERR,
4405                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4406                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4407                                                le16_to_cpu(gdp->bg_checksum));
4408                                         err = -EINVAL;
4409                                         goto restore_opts;
4410                                 }
4411                         }
4412
4413                         /*
4414                          * If we have an unprocessed orphan list hanging
4415                          * around from a previously readonly bdev mount,
4416                          * require a full umount/remount for now.
4417                          */
4418                         if (es->s_last_orphan) {
4419                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4420                                        "remount RDWR because of unprocessed "
4421                                        "orphan inode list.  Please "
4422                                        "umount/remount instead");
4423                                 err = -EINVAL;
4424                                 goto restore_opts;
4425                         }
4426
4427                         /*
4428                          * Mounting a RDONLY partition read-write, so reread
4429                          * and store the current valid flag.  (It may have
4430                          * been changed by e2fsck since we originally mounted
4431                          * the partition.)
4432                          */
4433                         if (sbi->s_journal)
4434                                 ext4_clear_journal_err(sb, es);
4435                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4436                         if (!ext4_setup_super(sb, es, 0))
4437                                 sb->s_flags &= ~MS_RDONLY;
4438                         if (EXT4_HAS_INCOMPAT_FEATURE(sb,
4439                                                      EXT4_FEATURE_INCOMPAT_MMP))
4440                                 if (ext4_multi_mount_protect(sb,
4441                                                 le64_to_cpu(es->s_mmp_block))) {
4442                                         err = -EROFS;
4443                                         goto restore_opts;
4444                                 }
4445                         enable_quota = 1;
4446                 }
4447         }
4448
4449         /*
4450          * Reinitialize lazy itable initialization thread based on
4451          * current settings
4452          */
4453         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4454                 ext4_unregister_li_request(sb);
4455         else {
4456                 ext4_group_t first_not_zeroed;
4457                 first_not_zeroed = ext4_has_uninit_itable(sb);
4458                 ext4_register_li_request(sb, first_not_zeroed);
4459         }
4460
4461         ext4_setup_system_zone(sb);
4462         if (sbi->s_journal == NULL)
4463                 ext4_commit_super(sb, 1);
4464
4465 #ifdef CONFIG_QUOTA
4466         /* Release old quota file names */
4467         for (i = 0; i < MAXQUOTAS; i++)
4468                 if (old_opts.s_qf_names[i] &&
4469                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4470                         kfree(old_opts.s_qf_names[i]);
4471 #endif
4472         unlock_super(sb);
4473         if (enable_quota)
4474                 dquot_resume(sb, -1);
4475
4476         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4477         kfree(orig_data);
4478         return 0;
4479
4480 restore_opts:
4481         sb->s_flags = old_sb_flags;
4482         sbi->s_mount_opt = old_opts.s_mount_opt;
4483         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4484         sbi->s_resuid = old_opts.s_resuid;
4485         sbi->s_resgid = old_opts.s_resgid;
4486         sbi->s_commit_interval = old_opts.s_commit_interval;
4487         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4488         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4489 #ifdef CONFIG_QUOTA
4490         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4491         for (i = 0; i < MAXQUOTAS; i++) {
4492                 if (sbi->s_qf_names[i] &&
4493                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4494                         kfree(sbi->s_qf_names[i]);
4495                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4496         }
4497 #endif
4498         unlock_super(sb);
4499         kfree(orig_data);
4500         return err;
4501 }
4502
4503 /*
4504  * Note: calculating the overhead so we can be compatible with
4505  * historical BSD practice is quite difficult in the face of
4506  * clusters/bigalloc.  This is because multiple metadata blocks from
4507  * different block group can end up in the same allocation cluster.
4508  * Calculating the exact overhead in the face of clustered allocation
4509  * requires either O(all block bitmaps) in memory or O(number of block
4510  * groups**2) in time.  We will still calculate the superblock for
4511  * older file systems --- and if we come across with a bigalloc file
4512  * system with zero in s_overhead_clusters the estimate will be close to
4513  * correct especially for very large cluster sizes --- but for newer
4514  * file systems, it's better to calculate this figure once at mkfs
4515  * time, and store it in the superblock.  If the superblock value is
4516  * present (even for non-bigalloc file systems), we will use it.
4517  */
4518 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4519 {
4520         struct super_block *sb = dentry->d_sb;
4521         struct ext4_sb_info *sbi = EXT4_SB(sb);
4522         struct ext4_super_block *es = sbi->s_es;
4523         struct ext4_group_desc *gdp;
4524         u64 fsid;
4525         s64 bfree;
4526
4527         if (test_opt(sb, MINIX_DF)) {
4528                 sbi->s_overhead_last = 0;
4529         } else if (es->s_overhead_clusters) {
4530                 sbi->s_overhead_last = le32_to_cpu(es->s_overhead_clusters);
4531         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
4532                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4533                 ext4_fsblk_t overhead = 0;
4534
4535                 /*
4536                  * Compute the overhead (FS structures).  This is constant
4537                  * for a given filesystem unless the number of block groups
4538                  * changes so we cache the previous value until it does.
4539                  */
4540
4541                 /*
4542                  * All of the blocks before first_data_block are
4543                  * overhead
4544                  */
4545                 overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4546
4547                 /*
4548                  * Add the overhead found in each block group
4549                  */
4550                 for (i = 0; i < ngroups; i++) {
4551                         gdp = ext4_get_group_desc(sb, i, NULL);
4552                         overhead += ext4_num_overhead_clusters(sb, i, gdp);
4553                         cond_resched();
4554                 }
4555                 sbi->s_overhead_last = overhead;
4556                 smp_wmb();
4557                 sbi->s_blocks_last = ext4_blocks_count(es);
4558         }
4559
4560         buf->f_type = EXT4_SUPER_MAGIC;
4561         buf->f_bsize = sb->s_blocksize;
4562         buf->f_blocks = (ext4_blocks_count(es) -
4563                          EXT4_C2B(sbi, sbi->s_overhead_last));
4564         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
4565                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
4566         /* prevent underflow in case that few free space is available */
4567         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
4568         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
4569         if (buf->f_bfree < ext4_r_blocks_count(es))
4570                 buf->f_bavail = 0;
4571         buf->f_files = le32_to_cpu(es->s_inodes_count);
4572         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4573         buf->f_namelen = EXT4_NAME_LEN;
4574         fsid = le64_to_cpup((void *)es->s_uuid) ^
4575                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4576         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4577         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4578
4579         return 0;
4580 }
4581
4582 /* Helper function for writing quotas on sync - we need to start transaction
4583  * before quota file is locked for write. Otherwise the are possible deadlocks:
4584  * Process 1                         Process 2
4585  * ext4_create()                     quota_sync()
4586  *   jbd2_journal_start()                  write_dquot()
4587  *   dquot_initialize()                         down(dqio_mutex)
4588  *     down(dqio_mutex)                    jbd2_journal_start()
4589  *
4590  */
4591
4592 #ifdef CONFIG_QUOTA
4593
4594 static inline struct inode *dquot_to_inode(struct dquot *dquot)
4595 {
4596         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
4597 }
4598
4599 static int ext4_write_dquot(struct dquot *dquot)
4600 {
4601         int ret, err;
4602         handle_t *handle;
4603         struct inode *inode;
4604
4605         inode = dquot_to_inode(dquot);
4606         handle = ext4_journal_start(inode,
4607                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4608         if (IS_ERR(handle))
4609                 return PTR_ERR(handle);
4610         ret = dquot_commit(dquot);
4611         err = ext4_journal_stop(handle);
4612         if (!ret)
4613                 ret = err;
4614         return ret;
4615 }
4616
4617 static int ext4_acquire_dquot(struct dquot *dquot)
4618 {
4619         int ret, err;
4620         handle_t *handle;
4621
4622         handle = ext4_journal_start(dquot_to_inode(dquot),
4623                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4624         if (IS_ERR(handle))
4625                 return PTR_ERR(handle);
4626         ret = dquot_acquire(dquot);
4627         err = ext4_journal_stop(handle);
4628         if (!ret)
4629                 ret = err;
4630         return ret;
4631 }
4632
4633 static int ext4_release_dquot(struct dquot *dquot)
4634 {
4635         int ret, err;
4636         handle_t *handle;
4637
4638         handle = ext4_journal_start(dquot_to_inode(dquot),
4639                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4640         if (IS_ERR(handle)) {
4641                 /* Release dquot anyway to avoid endless cycle in dqput() */
4642                 dquot_release(dquot);
4643                 return PTR_ERR(handle);
4644         }
4645         ret = dquot_release(dquot);
4646         err = ext4_journal_stop(handle);
4647         if (!ret)
4648                 ret = err;
4649         return ret;
4650 }
4651
4652 static int ext4_mark_dquot_dirty(struct dquot *dquot)
4653 {
4654         /* Are we journaling quotas? */
4655         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
4656             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
4657                 dquot_mark_dquot_dirty(dquot);
4658                 return ext4_write_dquot(dquot);
4659         } else {
4660                 return dquot_mark_dquot_dirty(dquot);
4661         }
4662 }
4663
4664 static int ext4_write_info(struct super_block *sb, int type)
4665 {
4666         int ret, err;
4667         handle_t *handle;
4668
4669         /* Data block + inode block */
4670         handle = ext4_journal_start(sb->s_root->d_inode, 2);
4671         if (IS_ERR(handle))
4672                 return PTR_ERR(handle);
4673         ret = dquot_commit_info(sb, type);
4674         err = ext4_journal_stop(handle);
4675         if (!ret)
4676                 ret = err;
4677         return ret;
4678 }
4679
4680 /*
4681  * Turn on quotas during mount time - we need to find
4682  * the quota file and such...
4683  */
4684 static int ext4_quota_on_mount(struct super_block *sb, int type)
4685 {
4686         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4687                                         EXT4_SB(sb)->s_jquota_fmt, type);
4688 }
4689
4690 /*
4691  * Standard function to be called on quota_on
4692  */
4693 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4694                          struct path *path)
4695 {
4696         int err;
4697
4698         if (!test_opt(sb, QUOTA))
4699                 return -EINVAL;
4700
4701         /* Quotafile not on the same filesystem? */
4702         if (path->dentry->d_sb != sb)
4703                 return -EXDEV;
4704         /* Journaling quota? */
4705         if (EXT4_SB(sb)->s_qf_names[type]) {
4706                 /* Quotafile not in fs root? */
4707                 if (path->dentry->d_parent != sb->s_root)
4708                         ext4_msg(sb, KERN_WARNING,
4709                                 "Quota file not on filesystem root. "
4710                                 "Journaled quota will not work");
4711         }
4712
4713         /*
4714          * When we journal data on quota file, we have to flush journal to see
4715          * all updates to the file when we bypass pagecache...
4716          */
4717         if (EXT4_SB(sb)->s_journal &&
4718             ext4_should_journal_data(path->dentry->d_inode)) {
4719                 /*
4720                  * We don't need to lock updates but journal_flush() could
4721                  * otherwise be livelocked...
4722                  */
4723                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4724                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4725                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4726                 if (err)
4727                         return err;
4728         }
4729
4730         return dquot_quota_on(sb, type, format_id, path);
4731 }
4732
4733 static int ext4_quota_off(struct super_block *sb, int type)
4734 {
4735         struct inode *inode = sb_dqopt(sb)->files[type];
4736         handle_t *handle;
4737
4738         /* Force all delayed allocation blocks to be allocated.
4739          * Caller already holds s_umount sem */
4740         if (test_opt(sb, DELALLOC))
4741                 sync_filesystem(sb);
4742
4743         if (!inode)
4744                 goto out;
4745
4746         /* Update modification times of quota files when userspace can
4747          * start looking at them */
4748         handle = ext4_journal_start(inode, 1);
4749         if (IS_ERR(handle))
4750                 goto out;
4751         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
4752         ext4_mark_inode_dirty(handle, inode);
4753         ext4_journal_stop(handle);
4754
4755 out:
4756         return dquot_quota_off(sb, type);
4757 }
4758
4759 /* Read data from quotafile - avoid pagecache and such because we cannot afford
4760  * acquiring the locks... As quota files are never truncated and quota code
4761  * itself serializes the operations (and no one else should touch the files)
4762  * we don't have to be afraid of races */
4763 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
4764                                size_t len, loff_t off)
4765 {
4766         struct inode *inode = sb_dqopt(sb)->files[type];
4767         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4768         int err = 0;
4769         int offset = off & (sb->s_blocksize - 1);
4770         int tocopy;
4771         size_t toread;
4772         struct buffer_head *bh;
4773         loff_t i_size = i_size_read(inode);
4774
4775         if (off > i_size)
4776                 return 0;
4777         if (off+len > i_size)
4778                 len = i_size-off;
4779         toread = len;
4780         while (toread > 0) {
4781                 tocopy = sb->s_blocksize - offset < toread ?
4782                                 sb->s_blocksize - offset : toread;
4783                 bh = ext4_bread(NULL, inode, blk, 0, &err);
4784                 if (err)
4785                         return err;
4786                 if (!bh)        /* A hole? */
4787                         memset(data, 0, tocopy);
4788                 else
4789                         memcpy(data, bh->b_data+offset, tocopy);
4790                 brelse(bh);
4791                 offset = 0;
4792                 toread -= tocopy;
4793                 data += tocopy;
4794                 blk++;
4795         }
4796         return len;
4797 }
4798
4799 /* Write to quotafile (we know the transaction is already started and has
4800  * enough credits) */
4801 static ssize_t ext4_quota_write(struct super_block *sb, int type,
4802                                 const char *data, size_t len, loff_t off)
4803 {
4804         struct inode *inode = sb_dqopt(sb)->files[type];
4805         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4806         int err = 0;
4807         int offset = off & (sb->s_blocksize - 1);
4808         struct buffer_head *bh;
4809         handle_t *handle = journal_current_handle();
4810
4811         if (EXT4_SB(sb)->s_journal && !handle) {
4812                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4813                         " cancelled because transaction is not started",
4814                         (unsigned long long)off, (unsigned long long)len);
4815                 return -EIO;
4816         }
4817         /*
4818          * Since we account only one data block in transaction credits,
4819          * then it is impossible to cross a block boundary.
4820          */
4821         if (sb->s_blocksize - offset < len) {
4822                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4823                         " cancelled because not block aligned",
4824                         (unsigned long long)off, (unsigned long long)len);
4825                 return -EIO;
4826         }
4827
4828         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
4829         bh = ext4_bread(handle, inode, blk, 1, &err);
4830         if (!bh)
4831                 goto out;
4832         err = ext4_journal_get_write_access(handle, bh);
4833         if (err) {
4834                 brelse(bh);
4835                 goto out;
4836         }
4837         lock_buffer(bh);
4838         memcpy(bh->b_data+offset, data, len);
4839         flush_dcache_page(bh->b_page);
4840         unlock_buffer(bh);
4841         err = ext4_handle_dirty_metadata(handle, NULL, bh);
4842         brelse(bh);
4843 out:
4844         if (err) {
4845                 mutex_unlock(&inode->i_mutex);
4846                 return err;
4847         }
4848         if (inode->i_size < off + len) {
4849                 i_size_write(inode, off + len);
4850                 EXT4_I(inode)->i_disksize = inode->i_size;
4851                 ext4_mark_inode_dirty(handle, inode);
4852         }
4853         mutex_unlock(&inode->i_mutex);
4854         return len;
4855 }
4856
4857 #endif
4858
4859 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
4860                        const char *dev_name, void *data)
4861 {
4862         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
4863 }
4864
4865 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4866 static inline void register_as_ext2(void)
4867 {
4868         int err = register_filesystem(&ext2_fs_type);
4869         if (err)
4870                 printk(KERN_WARNING
4871                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
4872 }
4873
4874 static inline void unregister_as_ext2(void)
4875 {
4876         unregister_filesystem(&ext2_fs_type);
4877 }
4878
4879 static inline int ext2_feature_set_ok(struct super_block *sb)
4880 {
4881         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
4882                 return 0;
4883         if (sb->s_flags & MS_RDONLY)
4884                 return 1;
4885         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
4886                 return 0;
4887         return 1;
4888 }
4889 MODULE_ALIAS("ext2");
4890 #else
4891 static inline void register_as_ext2(void) { }
4892 static inline void unregister_as_ext2(void) { }
4893 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
4894 #endif
4895
4896 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4897 static inline void register_as_ext3(void)
4898 {
4899         int err = register_filesystem(&ext3_fs_type);
4900         if (err)
4901                 printk(KERN_WARNING
4902                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
4903 }
4904
4905 static inline void unregister_as_ext3(void)
4906 {
4907         unregister_filesystem(&ext3_fs_type);
4908 }
4909
4910 static inline int ext3_feature_set_ok(struct super_block *sb)
4911 {
4912         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
4913                 return 0;
4914         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
4915                 return 0;
4916         if (sb->s_flags & MS_RDONLY)
4917                 return 1;
4918         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
4919                 return 0;
4920         return 1;
4921 }
4922 MODULE_ALIAS("ext3");
4923 #else
4924 static inline void register_as_ext3(void) { }
4925 static inline void unregister_as_ext3(void) { }
4926 static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
4927 #endif
4928
4929 static struct file_system_type ext4_fs_type = {
4930         .owner          = THIS_MODULE,
4931         .name           = "ext4",
4932         .mount          = ext4_mount,
4933         .kill_sb        = kill_block_super,
4934         .fs_flags       = FS_REQUIRES_DEV,
4935 };
4936
4937 static int __init ext4_init_feat_adverts(void)
4938 {
4939         struct ext4_features *ef;
4940         int ret = -ENOMEM;
4941
4942         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
4943         if (!ef)
4944                 goto out;
4945
4946         ef->f_kobj.kset = ext4_kset;
4947         init_completion(&ef->f_kobj_unregister);
4948         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
4949                                    "features");
4950         if (ret) {
4951                 kfree(ef);
4952                 goto out;
4953         }
4954
4955         ext4_feat = ef;
4956         ret = 0;
4957 out:
4958         return ret;
4959 }
4960
4961 static void ext4_exit_feat_adverts(void)
4962 {
4963         kobject_put(&ext4_feat->f_kobj);
4964         wait_for_completion(&ext4_feat->f_kobj_unregister);
4965         kfree(ext4_feat);
4966 }
4967
4968 /* Shared across all ext4 file systems */
4969 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
4970 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
4971
4972 static int __init ext4_init_fs(void)
4973 {
4974         int i, err;
4975
4976         ext4_li_info = NULL;
4977         mutex_init(&ext4_li_mtx);
4978
4979         ext4_check_flag_values();
4980
4981         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
4982                 mutex_init(&ext4__aio_mutex[i]);
4983                 init_waitqueue_head(&ext4__ioend_wq[i]);
4984         }
4985
4986         err = ext4_init_pageio();
4987         if (err)
4988                 return err;
4989         err = ext4_init_system_zone();
4990         if (err)
4991                 goto out6;
4992         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
4993         if (!ext4_kset)
4994                 goto out5;
4995         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
4996
4997         err = ext4_init_feat_adverts();
4998         if (err)
4999                 goto out4;
5000
5001         err = ext4_init_mballoc();
5002         if (err)
5003                 goto out3;
5004
5005         err = ext4_init_xattr();
5006         if (err)
5007                 goto out2;
5008         err = init_inodecache();
5009         if (err)
5010                 goto out1;
5011         register_as_ext3();
5012         register_as_ext2();
5013         err = register_filesystem(&ext4_fs_type);
5014         if (err)
5015                 goto out;
5016
5017         return 0;
5018 out:
5019         unregister_as_ext2();
5020         unregister_as_ext3();
5021         destroy_inodecache();
5022 out1:
5023         ext4_exit_xattr();
5024 out2:
5025         ext4_exit_mballoc();
5026 out3:
5027         ext4_exit_feat_adverts();
5028 out4:
5029         if (ext4_proc_root)
5030                 remove_proc_entry("fs/ext4", NULL);
5031         kset_unregister(ext4_kset);
5032 out5:
5033         ext4_exit_system_zone();
5034 out6:
5035         ext4_exit_pageio();
5036         return err;
5037 }
5038
5039 static void __exit ext4_exit_fs(void)
5040 {
5041         ext4_destroy_lazyinit_thread();
5042         unregister_as_ext2();
5043         unregister_as_ext3();
5044         unregister_filesystem(&ext4_fs_type);
5045         destroy_inodecache();
5046         ext4_exit_xattr();
5047         ext4_exit_mballoc();
5048         ext4_exit_feat_adverts();
5049         remove_proc_entry("fs/ext4", NULL);
5050         kset_unregister(ext4_kset);
5051         ext4_exit_system_zone();
5052         ext4_exit_pageio();
5053 }
5054
5055 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5056 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5057 MODULE_LICENSE("GPL");
5058 module_init(ext4_init_fs)
5059 module_exit(ext4_exit_fs)