Pileus Git - ~andy/linux/blob - fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/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 linux-ext4@vger.kernel.org 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 static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1956                                    struct ext4_group_desc *gdp)
1957 {
1958         int offset;
1959         __u16 crc = 0;
1960         __le32 le_group = cpu_to_le32(block_group);
1961
1962         if ((sbi->s_es->s_feature_ro_compat &
1963              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))) {
1964                 /* Use new metadata_csum algorithm */
1965                 __u16 old_csum;
1966                 __u32 csum32;
1967
1968                 old_csum = gdp->bg_checksum;
1969                 gdp->bg_checksum = 0;
1970                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
1971                                      sizeof(le_group));
1972                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
1973                                      sbi->s_desc_size);
1974                 gdp->bg_checksum = old_csum;
1975
1976                 crc = csum32 & 0xFFFF;
1977                 goto out;
1978         }
1979
1980         /* old crc16 code */
1981         offset = offsetof(struct ext4_group_desc, bg_checksum);
1982
1983         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1984         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1985         crc = crc16(crc, (__u8 *)gdp, offset);
1986         offset += sizeof(gdp->bg_checksum); /* skip checksum */
1987         /* for checksum of struct ext4_group_desc do the rest...*/
1988         if ((sbi->s_es->s_feature_incompat &
1989              cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1990             offset < le16_to_cpu(sbi->s_es->s_desc_size))
1991                 crc = crc16(crc, (__u8 *)gdp + offset,
1992                             le16_to_cpu(sbi->s_es->s_desc_size) -
1993                                 offset);
1994
1995 out:
1996         return cpu_to_le16(crc);
1997 }
1998
1999 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2000                                 struct ext4_group_desc *gdp)
2001 {
2002         if (ext4_has_group_desc_csum(sb) &&
2003             (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
2004                                                       block_group, gdp)))
2005                 return 0;
2006
2007         return 1;
2008 }
2009
2010 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2011                               struct ext4_group_desc *gdp)
2012 {
2013         if (!ext4_has_group_desc_csum(sb))
2014                 return;
2015         gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
2016 }
2017
2018 /* Called at mount-time, super-block is locked */
2019 static int ext4_check_descriptors(struct super_block *sb,
2020                                   ext4_group_t *first_not_zeroed)
2021 {
2022         struct ext4_sb_info *sbi = EXT4_SB(sb);
2023         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2024         ext4_fsblk_t last_block;
2025         ext4_fsblk_t block_bitmap;
2026         ext4_fsblk_t inode_bitmap;
2027         ext4_fsblk_t inode_table;
2028         int flexbg_flag = 0;
2029         ext4_group_t i, grp = sbi->s_groups_count;
2030
2031         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2032                 flexbg_flag = 1;
2033
2034         ext4_debug("Checking group descriptors");
2035
2036         for (i = 0; i < sbi->s_groups_count; i++) {
2037                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2038
2039                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2040                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2041                 else
2042                         last_block = first_block +
2043                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2044
2045                 if ((grp == sbi->s_groups_count) &&
2046                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2047                         grp = i;
2048
2049                 block_bitmap = ext4_block_bitmap(sb, gdp);
2050                 if (block_bitmap < first_block || block_bitmap > last_block) {
2051                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2052                                "Block bitmap for group %u not in group "
2053                                "(block %llu)!", i, block_bitmap);
2054                         return 0;
2055                 }
2056                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2057                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2058                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2059                                "Inode bitmap for group %u not in group "
2060                                "(block %llu)!", i, inode_bitmap);
2061                         return 0;
2062                 }
2063                 inode_table = ext4_inode_table(sb, gdp);
2064                 if (inode_table < first_block ||
2065                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2066                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2067                                "Inode table for group %u not in group "
2068                                "(block %llu)!", i, inode_table);
2069                         return 0;
2070                 }
2071                 ext4_lock_group(sb, i);
2072                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2073                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2074                                  "Checksum for group %u failed (%u!=%u)",
2075                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2076                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2077                         if (!(sb->s_flags & MS_RDONLY)) {
2078                                 ext4_unlock_group(sb, i);
2079                                 return 0;
2080                         }
2081                 }
2082                 ext4_unlock_group(sb, i);
2083                 if (!flexbg_flag)
2084                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2085         }
2086         if (NULL != first_not_zeroed)
2087                 *first_not_zeroed = grp;
2088
2089         ext4_free_blocks_count_set(sbi->s_es,
2090                                    EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2091         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2092         return 1;
2093 }
2094
2095 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2096  * the superblock) which were deleted from all directories, but held open by
2097  * a process at the time of a crash.  We walk the list and try to delete these
2098  * inodes at recovery time (only with a read-write filesystem).
2099  *
2100  * In order to keep the orphan inode chain consistent during traversal (in
2101  * case of crash during recovery), we link each inode into the superblock
2102  * orphan list_head and handle it the same way as an inode deletion during
2103  * normal operation (which journals the operations for us).
2104  *
2105  * We only do an iget() and an iput() on each inode, which is very safe if we
2106  * accidentally point at an in-use or already deleted inode.  The worst that
2107  * can happen in this case is that we get a "bit already cleared" message from
2108  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2109  * e2fsck was run on this filesystem, and it must have already done the orphan
2110  * inode cleanup for us, so we can safely abort without any further action.
2111  */
2112 static void ext4_orphan_cleanup(struct super_block *sb,
2113                                 struct ext4_super_block *es)
2114 {
2115         unsigned int s_flags = sb->s_flags;
2116         int nr_orphans = 0, nr_truncates = 0;
2117 #ifdef CONFIG_QUOTA
2118         int i;
2119 #endif
2120         if (!es->s_last_orphan) {
2121                 jbd_debug(4, "no orphan inodes to clean up\n");
2122                 return;
2123         }
2124
2125         if (bdev_read_only(sb->s_bdev)) {
2126                 ext4_msg(sb, KERN_ERR, "write access "
2127                         "unavailable, skipping orphan cleanup");
2128                 return;
2129         }
2130
2131         /* Check if feature set would not allow a r/w mount */
2132         if (!ext4_feature_set_ok(sb, 0)) {
2133                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2134                          "unknown ROCOMPAT features");
2135                 return;
2136         }
2137
2138         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2139                 if (es->s_last_orphan)
2140                         jbd_debug(1, "Errors on filesystem, "
2141                                   "clearing orphan list.\n");
2142                 es->s_last_orphan = 0;
2143                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2144                 return;
2145         }
2146
2147         if (s_flags & MS_RDONLY) {
2148                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2149                 sb->s_flags &= ~MS_RDONLY;
2150         }
2151 #ifdef CONFIG_QUOTA
2152         /* Needed for iput() to work correctly and not trash data */
2153         sb->s_flags |= MS_ACTIVE;
2154         /* Turn on quotas so that they are updated correctly */
2155         for (i = 0; i < MAXQUOTAS; i++) {
2156                 if (EXT4_SB(sb)->s_qf_names[i]) {
2157                         int ret = ext4_quota_on_mount(sb, i);
2158                         if (ret < 0)
2159                                 ext4_msg(sb, KERN_ERR,
2160                                         "Cannot turn on journaled "
2161                                         "quota: error %d", ret);
2162                 }
2163         }
2164 #endif
2165
2166         while (es->s_last_orphan) {
2167                 struct inode *inode;
2168
2169                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2170                 if (IS_ERR(inode)) {
2171                         es->s_last_orphan = 0;
2172                         break;
2173                 }
2174
2175                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2176                 dquot_initialize(inode);
2177                 if (inode->i_nlink) {
2178                         ext4_msg(sb, KERN_DEBUG,
2179                                 "%s: truncating inode %lu to %lld bytes",
2180                                 __func__, inode->i_ino, inode->i_size);
2181                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2182                                   inode->i_ino, inode->i_size);
2183                         ext4_truncate(inode);
2184                         nr_truncates++;
2185                 } else {
2186                         ext4_msg(sb, KERN_DEBUG,
2187                                 "%s: deleting unreferenced inode %lu",
2188                                 __func__, inode->i_ino);
2189                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2190                                   inode->i_ino);
2191                         nr_orphans++;
2192                 }
2193                 iput(inode);  /* The delete magic happens here! */
2194         }
2195
2196 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2197
2198         if (nr_orphans)
2199                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2200                        PLURAL(nr_orphans));
2201         if (nr_truncates)
2202                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2203                        PLURAL(nr_truncates));
2204 #ifdef CONFIG_QUOTA
2205         /* Turn quotas off */
2206         for (i = 0; i < MAXQUOTAS; i++) {
2207                 if (sb_dqopt(sb)->files[i])
2208                         dquot_quota_off(sb, i);
2209         }
2210 #endif
2211         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2212 }
2213
2214 /*
2215  * Maximal extent format file size.
2216  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2217  * extent format containers, within a sector_t, and within i_blocks
2218  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2219  * so that won't be a limiting factor.
2220  *
2221  * However there is other limiting factor. We do store extents in the form
2222  * of starting block and length, hence the resulting length of the extent
2223  * covering maximum file size must fit into on-disk format containers as
2224  * well. Given that length is always by 1 unit bigger than max unit (because
2225  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2226  *
2227  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2228  */
2229 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2230 {
2231         loff_t res;
2232         loff_t upper_limit = MAX_LFS_FILESIZE;
2233
2234         /* small i_blocks in vfs inode? */
2235         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2236                 /*
2237                  * CONFIG_LBDAF is not enabled implies the inode
2238                  * i_block represent total blocks in 512 bytes
2239                  * 32 == size of vfs inode i_blocks * 8
2240                  */
2241                 upper_limit = (1LL << 32) - 1;
2242
2243                 /* total blocks in file system block size */
2244                 upper_limit >>= (blkbits - 9);
2245                 upper_limit <<= blkbits;
2246         }
2247
2248         /*
2249          * 32-bit extent-start container, ee_block. We lower the maxbytes
2250          * by one fs block, so ee_len can cover the extent of maximum file
2251          * size
2252          */
2253         res = (1LL << 32) - 1;
2254         res <<= blkbits;
2255
2256         /* Sanity check against vm- & vfs- imposed limits */
2257         if (res > upper_limit)
2258                 res = upper_limit;
2259
2260         return res;
2261 }
2262
2263 /*
2264  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2265  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2266  * We need to be 1 filesystem block less than the 2^48 sector limit.
2267  */
2268 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2269 {
2270         loff_t res = EXT4_NDIR_BLOCKS;
2271         int meta_blocks;
2272         loff_t upper_limit;
2273         /* This is calculated to be the largest file size for a dense, block
2274          * mapped file such that the file's total number of 512-byte sectors,
2275          * including data and all indirect blocks, does not exceed (2^48 - 1).
2276          *
2277          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2278          * number of 512-byte sectors of the file.
2279          */
2280
2281         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2282                 /*
2283                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2284                  * the inode i_block field represents total file blocks in
2285                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2286                  */
2287                 upper_limit = (1LL << 32) - 1;
2288
2289                 /* total blocks in file system block size */
2290                 upper_limit >>= (bits - 9);
2291
2292         } else {
2293                 /*
2294                  * We use 48 bit ext4_inode i_blocks
2295                  * With EXT4_HUGE_FILE_FL set the i_blocks
2296                  * represent total number of blocks in
2297                  * file system block size
2298                  */
2299                 upper_limit = (1LL << 48) - 1;
2300
2301         }
2302
2303         /* indirect blocks */
2304         meta_blocks = 1;
2305         /* double indirect blocks */
2306         meta_blocks += 1 + (1LL << (bits-2));
2307         /* tripple indirect blocks */
2308         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2309
2310         upper_limit -= meta_blocks;
2311         upper_limit <<= bits;
2312
2313         res += 1LL << (bits-2);
2314         res += 1LL << (2*(bits-2));
2315         res += 1LL << (3*(bits-2));
2316         res <<= bits;
2317         if (res > upper_limit)
2318                 res = upper_limit;
2319
2320         if (res > MAX_LFS_FILESIZE)
2321                 res = MAX_LFS_FILESIZE;
2322
2323         return res;
2324 }
2325
2326 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2327                                    ext4_fsblk_t logical_sb_block, int nr)
2328 {
2329         struct ext4_sb_info *sbi = EXT4_SB(sb);
2330         ext4_group_t bg, first_meta_bg;
2331         int has_super = 0;
2332
2333         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2334
2335         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2336             nr < first_meta_bg)
2337                 return logical_sb_block + nr + 1;
2338         bg = sbi->s_desc_per_block * nr;
2339         if (ext4_bg_has_super(sb, bg))
2340                 has_super = 1;
2341
2342         return (has_super + ext4_group_first_block_no(sb, bg));
2343 }
2344
2345 /**
2346  * ext4_get_stripe_size: Get the stripe size.
2347  * @sbi: In memory super block info
2348  *
2349  * If we have specified it via mount option, then
2350  * use the mount option value. If the value specified at mount time is
2351  * greater than the blocks per group use the super block value.
2352  * If the super block value is greater than blocks per group return 0.
2353  * Allocator needs it be less than blocks per group.
2354  *
2355  */
2356 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2357 {
2358         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2359         unsigned long stripe_width =
2360                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2361         int ret;
2362
2363         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2364                 ret = sbi->s_stripe;
2365         else if (stripe_width <= sbi->s_blocks_per_group)
2366                 ret = stripe_width;
2367         else if (stride <= sbi->s_blocks_per_group)
2368                 ret = stride;
2369         else
2370                 ret = 0;
2371
2372         /*
2373          * If the stripe width is 1, this makes no sense and
2374          * we set it to 0 to turn off stripe handling code.
2375          */
2376         if (ret <= 1)
2377                 ret = 0;
2378
2379         return ret;
2380 }
2381
2382 /* sysfs supprt */
2383
2384 struct ext4_attr {
2385         struct attribute attr;
2386         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2387         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2388                          const char *, size_t);
2389         int offset;
2390 };
2391
2392 static int parse_strtoul(const char *buf,
2393                 unsigned long max, unsigned long *value)
2394 {
2395         char *endp;
2396
2397         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2398         endp = skip_spaces(endp);
2399         if (*endp || *value > max)
2400                 return -EINVAL;
2401
2402         return 0;
2403 }
2404
2405 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2406                                               struct ext4_sb_info *sbi,
2407                                               char *buf)
2408 {
2409         return snprintf(buf, PAGE_SIZE, "%llu\n",
2410                 (s64) EXT4_C2B(sbi,
2411                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2412 }
2413
2414 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2415                                          struct ext4_sb_info *sbi, char *buf)
2416 {
2417         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2418
2419         if (!sb->s_bdev->bd_part)
2420                 return snprintf(buf, PAGE_SIZE, "0\n");
2421         return snprintf(buf, PAGE_SIZE, "%lu\n",
2422                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2423                          sbi->s_sectors_written_start) >> 1);
2424 }
2425
2426 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2427                                           struct ext4_sb_info *sbi, char *buf)
2428 {
2429         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2430
2431         if (!sb->s_bdev->bd_part)
2432                 return snprintf(buf, PAGE_SIZE, "0\n");
2433         return snprintf(buf, PAGE_SIZE, "%llu\n",
2434                         (unsigned long long)(sbi->s_kbytes_written +
2435                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2436                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2437 }
2438
2439 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2440                                           struct ext4_sb_info *sbi,
2441                                           const char *buf, size_t count)
2442 {
2443         unsigned long t;
2444
2445         if (parse_strtoul(buf, 0x40000000, &t))
2446                 return -EINVAL;
2447
2448         if (t && !is_power_of_2(t))
2449                 return -EINVAL;
2450
2451         sbi->s_inode_readahead_blks = t;
2452         return count;
2453 }
2454
2455 static ssize_t sbi_ui_show(struct ext4_attr *a,
2456                            struct ext4_sb_info *sbi, char *buf)
2457 {
2458         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2459
2460         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2461 }
2462
2463 static ssize_t sbi_ui_store(struct ext4_attr *a,
2464                             struct ext4_sb_info *sbi,
2465                             const char *buf, size_t count)
2466 {
2467         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2468         unsigned long t;
2469
2470         if (parse_strtoul(buf, 0xffffffff, &t))
2471                 return -EINVAL;
2472         *ui = t;
2473         return count;
2474 }
2475
2476 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2477 static struct ext4_attr ext4_attr_##_name = {                   \
2478         .attr = {.name = __stringify(_name), .mode = _mode },   \
2479         .show   = _show,                                        \
2480         .store  = _store,                                       \
2481         .offset = offsetof(struct ext4_sb_info, _elname),       \
2482 }
2483 #define EXT4_ATTR(name, mode, show, store) \
2484 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2485
2486 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2487 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2488 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2489 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2490         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2491 #define ATTR_LIST(name) &ext4_attr_##name.attr
2492
2493 EXT4_RO_ATTR(delayed_allocation_blocks);
2494 EXT4_RO_ATTR(session_write_kbytes);
2495 EXT4_RO_ATTR(lifetime_write_kbytes);
2496 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2497                  inode_readahead_blks_store, s_inode_readahead_blks);
2498 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2499 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2500 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2501 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2502 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2503 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2504 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2505 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2506
2507 static struct attribute *ext4_attrs[] = {
2508         ATTR_LIST(delayed_allocation_blocks),
2509         ATTR_LIST(session_write_kbytes),
2510         ATTR_LIST(lifetime_write_kbytes),
2511         ATTR_LIST(inode_readahead_blks),
2512         ATTR_LIST(inode_goal),
2513         ATTR_LIST(mb_stats),
2514         ATTR_LIST(mb_max_to_scan),
2515         ATTR_LIST(mb_min_to_scan),
2516         ATTR_LIST(mb_order2_req),
2517         ATTR_LIST(mb_stream_req),
2518         ATTR_LIST(mb_group_prealloc),
2519         ATTR_LIST(max_writeback_mb_bump),
2520         NULL,
2521 };
2522
2523 /* Features this copy of ext4 supports */
2524 EXT4_INFO_ATTR(lazy_itable_init);
2525 EXT4_INFO_ATTR(batched_discard);
2526
2527 static struct attribute *ext4_feat_attrs[] = {
2528         ATTR_LIST(lazy_itable_init),
2529         ATTR_LIST(batched_discard),
2530         NULL,
2531 };
2532
2533 static ssize_t ext4_attr_show(struct kobject *kobj,
2534                               struct attribute *attr, char *buf)
2535 {
2536         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2537                                                 s_kobj);
2538         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2539
2540         return a->show ? a->show(a, sbi, buf) : 0;
2541 }
2542
2543 static ssize_t ext4_attr_store(struct kobject *kobj,
2544                                struct attribute *attr,
2545                                const char *buf, size_t len)
2546 {
2547         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2548                                                 s_kobj);
2549         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2550
2551         return a->store ? a->store(a, sbi, buf, len) : 0;
2552 }
2553
2554 static void ext4_sb_release(struct kobject *kobj)
2555 {
2556         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2557                                                 s_kobj);
2558         complete(&sbi->s_kobj_unregister);
2559 }
2560
2561 static const struct sysfs_ops ext4_attr_ops = {
2562         .show   = ext4_attr_show,
2563         .store  = ext4_attr_store,
2564 };
2565
2566 static struct kobj_type ext4_ktype = {
2567         .default_attrs  = ext4_attrs,
2568         .sysfs_ops      = &ext4_attr_ops,
2569         .release        = ext4_sb_release,
2570 };
2571
2572 static void ext4_feat_release(struct kobject *kobj)
2573 {
2574         complete(&ext4_feat->f_kobj_unregister);
2575 }
2576
2577 static struct kobj_type ext4_feat_ktype = {
2578         .default_attrs  = ext4_feat_attrs,
2579         .sysfs_ops      = &ext4_attr_ops,
2580         .release        = ext4_feat_release,
2581 };
2582
2583 /*
2584  * Check whether this filesystem can be mounted based on
2585  * the features present and the RDONLY/RDWR mount requested.
2586  * Returns 1 if this filesystem can be mounted as requested,
2587  * 0 if it cannot be.
2588  */
2589 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2590 {
2591         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2592                 ext4_msg(sb, KERN_ERR,
2593                         "Couldn't mount because of "
2594                         "unsupported optional features (%x)",
2595                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2596                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2597                 return 0;
2598         }
2599
2600         if (readonly)
2601                 return 1;
2602
2603         /* Check that feature set is OK for a read-write mount */
2604         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2605                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2606                          "unsupported optional features (%x)",
2607                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2608                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2609                 return 0;
2610         }
2611         /*
2612          * Large file size enabled file system can only be mounted
2613          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2614          */
2615         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2616                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2617                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2618                                  "cannot be mounted RDWR without "
2619                                  "CONFIG_LBDAF");
2620                         return 0;
2621                 }
2622         }
2623         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2624             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2625                 ext4_msg(sb, KERN_ERR,
2626                          "Can't support bigalloc feature without "
2627                          "extents feature\n");
2628                 return 0;
2629         }
2630         return 1;
2631 }
2632
2633 /*
2634  * This function is called once a day if we have errors logged
2635  * on the file system
2636  */
2637 static void print_daily_error_info(unsigned long arg)
2638 {
2639         struct super_block *sb = (struct super_block *) arg;
2640         struct ext4_sb_info *sbi;
2641         struct ext4_super_block *es;
2642
2643         sbi = EXT4_SB(sb);
2644         es = sbi->s_es;
2645
2646         if (es->s_error_count)
2647                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2648                          le32_to_cpu(es->s_error_count));
2649         if (es->s_first_error_time) {
2650                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2651                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2652                        (int) sizeof(es->s_first_error_func),
2653                        es->s_first_error_func,
2654                        le32_to_cpu(es->s_first_error_line));
2655                 if (es->s_first_error_ino)
2656                         printk(": inode %u",
2657                                le32_to_cpu(es->s_first_error_ino));
2658                 if (es->s_first_error_block)
2659                         printk(": block %llu", (unsigned long long)
2660                                le64_to_cpu(es->s_first_error_block));
2661                 printk("\n");
2662         }
2663         if (es->s_last_error_time) {
2664                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2665                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2666                        (int) sizeof(es->s_last_error_func),
2667                        es->s_last_error_func,
2668                        le32_to_cpu(es->s_last_error_line));
2669                 if (es->s_last_error_ino)
2670                         printk(": inode %u",
2671                                le32_to_cpu(es->s_last_error_ino));
2672                 if (es->s_last_error_block)
2673                         printk(": block %llu", (unsigned long long)
2674                                le64_to_cpu(es->s_last_error_block));
2675                 printk("\n");
2676         }
2677         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2678 }
2679
2680 /* Find next suitable group and run ext4_init_inode_table */
2681 static int ext4_run_li_request(struct ext4_li_request *elr)
2682 {
2683         struct ext4_group_desc *gdp = NULL;
2684         ext4_group_t group, ngroups;
2685         struct super_block *sb;
2686         unsigned long timeout = 0;
2687         int ret = 0;
2688
2689         sb = elr->lr_super;
2690         ngroups = EXT4_SB(sb)->s_groups_count;
2691
2692         for (group = elr->lr_next_group; group < ngroups; group++) {
2693                 gdp = ext4_get_group_desc(sb, group, NULL);
2694                 if (!gdp) {
2695                         ret = 1;
2696                         break;
2697                 }
2698
2699                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2700                         break;
2701         }
2702
2703         if (group == ngroups)
2704                 ret = 1;
2705
2706         if (!ret) {
2707                 timeout = jiffies;
2708                 ret = ext4_init_inode_table(sb, group,
2709                                             elr->lr_timeout ? 0 : 1);
2710                 if (elr->lr_timeout == 0) {
2711                         timeout = (jiffies - timeout) *
2712                                   elr->lr_sbi->s_li_wait_mult;
2713                         elr->lr_timeout = timeout;
2714                 }
2715                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2716                 elr->lr_next_group = group + 1;
2717         }
2718
2719         return ret;
2720 }
2721
2722 /*
2723  * Remove lr_request from the list_request and free the
2724  * request structure. Should be called with li_list_mtx held
2725  */
2726 static void ext4_remove_li_request(struct ext4_li_request *elr)
2727 {
2728         struct ext4_sb_info *sbi;
2729
2730         if (!elr)
2731                 return;
2732
2733         sbi = elr->lr_sbi;
2734
2735         list_del(&elr->lr_request);
2736         sbi->s_li_request = NULL;
2737         kfree(elr);
2738 }
2739
2740 static void ext4_unregister_li_request(struct super_block *sb)
2741 {
2742         mutex_lock(&ext4_li_mtx);
2743         if (!ext4_li_info) {
2744                 mutex_unlock(&ext4_li_mtx);
2745                 return;
2746         }
2747
2748         mutex_lock(&ext4_li_info->li_list_mtx);
2749         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2750         mutex_unlock(&ext4_li_info->li_list_mtx);
2751         mutex_unlock(&ext4_li_mtx);
2752 }
2753
2754 static struct task_struct *ext4_lazyinit_task;
2755
2756 /*
2757  * This is the function where ext4lazyinit thread lives. It walks
2758  * through the request list searching for next scheduled filesystem.
2759  * When such a fs is found, run the lazy initialization request
2760  * (ext4_rn_li_request) and keep track of the time spend in this
2761  * function. Based on that time we compute next schedule time of
2762  * the request. When walking through the list is complete, compute
2763  * next waking time and put itself into sleep.
2764  */
2765 static int ext4_lazyinit_thread(void *arg)
2766 {
2767         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2768         struct list_head *pos, *n;
2769         struct ext4_li_request *elr;
2770         unsigned long next_wakeup, cur;
2771
2772         BUG_ON(NULL == eli);
2773
2774 cont_thread:
2775         while (true) {
2776                 next_wakeup = MAX_JIFFY_OFFSET;
2777
2778                 mutex_lock(&eli->li_list_mtx);
2779                 if (list_empty(&eli->li_request_list)) {
2780                         mutex_unlock(&eli->li_list_mtx);
2781                         goto exit_thread;
2782                 }
2783
2784                 list_for_each_safe(pos, n, &eli->li_request_list) {
2785                         elr = list_entry(pos, struct ext4_li_request,
2786                                          lr_request);
2787
2788                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2789                                 if (ext4_run_li_request(elr) != 0) {
2790                                         /* error, remove the lazy_init job */
2791                                         ext4_remove_li_request(elr);
2792                                         continue;
2793                                 }
2794                         }
2795
2796                         if (time_before(elr->lr_next_sched, next_wakeup))
2797                                 next_wakeup = elr->lr_next_sched;
2798                 }
2799                 mutex_unlock(&eli->li_list_mtx);
2800
2801                 try_to_freeze();
2802
2803                 cur = jiffies;
2804                 if ((time_after_eq(cur, next_wakeup)) ||
2805                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2806                         cond_resched();
2807                         continue;
2808                 }
2809
2810                 schedule_timeout_interruptible(next_wakeup - cur);
2811
2812                 if (kthread_should_stop()) {
2813                         ext4_clear_request_list();
2814                         goto exit_thread;
2815                 }
2816         }
2817
2818 exit_thread:
2819         /*
2820          * It looks like the request list is empty, but we need
2821          * to check it under the li_list_mtx lock, to prevent any
2822          * additions into it, and of course we should lock ext4_li_mtx
2823          * to atomically free the list and ext4_li_info, because at
2824          * this point another ext4 filesystem could be registering
2825          * new one.
2826          */
2827         mutex_lock(&ext4_li_mtx);
2828         mutex_lock(&eli->li_list_mtx);
2829         if (!list_empty(&eli->li_request_list)) {
2830                 mutex_unlock(&eli->li_list_mtx);
2831                 mutex_unlock(&ext4_li_mtx);
2832                 goto cont_thread;
2833         }
2834         mutex_unlock(&eli->li_list_mtx);
2835         kfree(ext4_li_info);
2836         ext4_li_info = NULL;
2837         mutex_unlock(&ext4_li_mtx);
2838
2839         return 0;
2840 }
2841
2842 static void ext4_clear_request_list(void)
2843 {
2844         struct list_head *pos, *n;
2845         struct ext4_li_request *elr;
2846
2847         mutex_lock(&ext4_li_info->li_list_mtx);
2848         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2849                 elr = list_entry(pos, struct ext4_li_request,
2850                                  lr_request);
2851                 ext4_remove_li_request(elr);
2852         }
2853         mutex_unlock(&ext4_li_info->li_list_mtx);
2854 }
2855
2856 static int ext4_run_lazyinit_thread(void)
2857 {
2858         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2859                                          ext4_li_info, "ext4lazyinit");
2860         if (IS_ERR(ext4_lazyinit_task)) {
2861                 int err = PTR_ERR(ext4_lazyinit_task);
2862                 ext4_clear_request_list();
2863                 kfree(ext4_li_info);
2864                 ext4_li_info = NULL;
2865                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
2866                                  "initialization thread\n",
2867                                  err);
2868                 return err;
2869         }
2870         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2871         return 0;
2872 }
2873
2874 /*
2875  * Check whether it make sense to run itable init. thread or not.
2876  * If there is at least one uninitialized inode table, return
2877  * corresponding group number, else the loop goes through all
2878  * groups and return total number of groups.
2879  */
2880 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2881 {
2882         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2883         struct ext4_group_desc *gdp = NULL;
2884
2885         for (group = 0; group < ngroups; group++) {
2886                 gdp = ext4_get_group_desc(sb, group, NULL);
2887                 if (!gdp)
2888                         continue;
2889
2890                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2891                         break;
2892         }
2893
2894         return group;
2895 }
2896
2897 static int ext4_li_info_new(void)
2898 {
2899         struct ext4_lazy_init *eli = NULL;
2900
2901         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2902         if (!eli)
2903                 return -ENOMEM;
2904
2905         INIT_LIST_HEAD(&eli->li_request_list);
2906         mutex_init(&eli->li_list_mtx);
2907
2908         eli->li_state |= EXT4_LAZYINIT_QUIT;
2909
2910         ext4_li_info = eli;
2911
2912         return 0;
2913 }
2914
2915 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2916                                             ext4_group_t start)
2917 {
2918         struct ext4_sb_info *sbi = EXT4_SB(sb);
2919         struct ext4_li_request *elr;
2920         unsigned long rnd;
2921
2922         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2923         if (!elr)
2924                 return NULL;
2925
2926         elr->lr_super = sb;
2927         elr->lr_sbi = sbi;
2928         elr->lr_next_group = start;
2929
2930         /*
2931          * Randomize first schedule time of the request to
2932          * spread the inode table initialization requests
2933          * better.
2934          */
2935         get_random_bytes(&rnd, sizeof(rnd));
2936         elr->lr_next_sched = jiffies + (unsigned long)rnd %
2937                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
2938
2939         return elr;
2940 }
2941
2942 static int ext4_register_li_request(struct super_block *sb,
2943                                     ext4_group_t first_not_zeroed)
2944 {
2945         struct ext4_sb_info *sbi = EXT4_SB(sb);
2946         struct ext4_li_request *elr;
2947         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2948         int ret = 0;
2949
2950         if (sbi->s_li_request != NULL) {
2951                 /*
2952                  * Reset timeout so it can be computed again, because
2953                  * s_li_wait_mult might have changed.
2954                  */
2955                 sbi->s_li_request->lr_timeout = 0;
2956                 return 0;
2957         }
2958
2959         if (first_not_zeroed == ngroups ||
2960             (sb->s_flags & MS_RDONLY) ||
2961             !test_opt(sb, INIT_INODE_TABLE))
2962                 return 0;
2963
2964         elr = ext4_li_request_new(sb, first_not_zeroed);
2965         if (!elr)
2966                 return -ENOMEM;
2967
2968         mutex_lock(&ext4_li_mtx);
2969
2970         if (NULL == ext4_li_info) {
2971                 ret = ext4_li_info_new();
2972                 if (ret)
2973                         goto out;
2974         }
2975
2976         mutex_lock(&ext4_li_info->li_list_mtx);
2977         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
2978         mutex_unlock(&ext4_li_info->li_list_mtx);
2979
2980         sbi->s_li_request = elr;
2981         /*
2982          * set elr to NULL here since it has been inserted to
2983          * the request_list and the removal and free of it is
2984          * handled by ext4_clear_request_list from now on.
2985          */
2986         elr = NULL;
2987
2988         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
2989                 ret = ext4_run_lazyinit_thread();
2990                 if (ret)
2991                         goto out;
2992         }
2993 out:
2994         mutex_unlock(&ext4_li_mtx);
2995         if (ret)
2996                 kfree(elr);
2997         return ret;
2998 }
2999
3000 /*
3001  * We do not need to lock anything since this is called on
3002  * module unload.
3003  */
3004 static void ext4_destroy_lazyinit_thread(void)
3005 {
3006         /*
3007          * If thread exited earlier
3008          * there's nothing to be done.
3009          */
3010         if (!ext4_li_info || !ext4_lazyinit_task)
3011                 return;
3012
3013         kthread_stop(ext4_lazyinit_task);
3014 }
3015
3016 static int set_journal_csum_feature_set(struct super_block *sb)
3017 {
3018         int ret = 1;
3019         int compat, incompat;
3020         struct ext4_sb_info *sbi = EXT4_SB(sb);
3021
3022         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3023                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3024                 /* journal checksum v2 */
3025                 compat = 0;
3026                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V2;
3027         } else {
3028                 /* journal checksum v1 */
3029                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3030                 incompat = 0;
3031         }
3032
3033         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3034                 ret = jbd2_journal_set_features(sbi->s_journal,
3035                                 compat, 0,
3036                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3037                                 incompat);
3038         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3039                 ret = jbd2_journal_set_features(sbi->s_journal,
3040                                 compat, 0,
3041                                 incompat);
3042                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3043                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3044         } else {
3045                 jbd2_journal_clear_features(sbi->s_journal,
3046                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3047                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3048                                 JBD2_FEATURE_INCOMPAT_CSUM_V2);
3049         }
3050
3051         return ret;
3052 }
3053
3054 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3055 {
3056         char *orig_data = kstrdup(data, GFP_KERNEL);
3057         struct buffer_head *bh;
3058         struct ext4_super_block *es = NULL;
3059         struct ext4_sb_info *sbi;
3060         ext4_fsblk_t block;
3061         ext4_fsblk_t sb_block = get_sb_block(&data);
3062         ext4_fsblk_t logical_sb_block;
3063         unsigned long offset = 0;
3064         unsigned long journal_devnum = 0;
3065         unsigned long def_mount_opts;
3066         struct inode *root;
3067         char *cp;
3068         const char *descr;
3069         int ret = -ENOMEM;
3070         int blocksize, clustersize;
3071         unsigned int db_count;
3072         unsigned int i;
3073         int needs_recovery, has_huge_files, has_bigalloc;
3074         __u64 blocks_count;
3075         int err;
3076         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3077         ext4_group_t first_not_zeroed;
3078
3079         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3080         if (!sbi)
3081                 goto out_free_orig;
3082
3083         sbi->s_blockgroup_lock =
3084                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3085         if (!sbi->s_blockgroup_lock) {
3086                 kfree(sbi);
3087                 goto out_free_orig;
3088         }
3089         sb->s_fs_info = sbi;
3090         sbi->s_mount_opt = 0;
3091         sbi->s_resuid = EXT4_DEF_RESUID;
3092         sbi->s_resgid = EXT4_DEF_RESGID;
3093         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3094         sbi->s_sb_block = sb_block;
3095         if (sb->s_bdev->bd_part)
3096                 sbi->s_sectors_written_start =
3097                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3098
3099         /* Cleanup superblock name */
3100         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3101                 *cp = '!';
3102
3103         ret = -EINVAL;
3104         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3105         if (!blocksize) {
3106                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3107                 goto out_fail;
3108         }
3109
3110         /*
3111          * The ext4 superblock will not be buffer aligned for other than 1kB
3112          * block sizes.  We need to calculate the offset from buffer start.
3113          */
3114         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3115                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3116                 offset = do_div(logical_sb_block, blocksize);
3117         } else {
3118                 logical_sb_block = sb_block;
3119         }
3120
3121         if (!(bh = sb_bread(sb, logical_sb_block))) {
3122                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3123                 goto out_fail;
3124         }
3125         /*
3126          * Note: s_es must be initialized as soon as possible because
3127          *       some ext4 macro-instructions depend on its value
3128          */
3129         es = (struct ext4_super_block *) (bh->b_data + offset);
3130         sbi->s_es = es;
3131         sb->s_magic = le16_to_cpu(es->s_magic);
3132         if (sb->s_magic != EXT4_SUPER_MAGIC)
3133                 goto cantfind_ext4;
3134         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3135
3136         /* Warn if metadata_csum and gdt_csum are both set. */
3137         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3138                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
3139             EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
3140                 ext4_warning(sb, KERN_INFO "metadata_csum and uninit_bg are "
3141                              "redundant flags; please run fsck.");
3142
3143         /* Check for a known checksum algorithm */
3144         if (!ext4_verify_csum_type(sb, es)) {
3145                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3146                          "unknown checksum algorithm.");
3147                 silent = 1;
3148                 goto cantfind_ext4;
3149         }
3150
3151         /* Load the checksum driver */
3152         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3153                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3154                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3155                 if (IS_ERR(sbi->s_chksum_driver)) {
3156                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3157                         ret = PTR_ERR(sbi->s_chksum_driver);
3158                         sbi->s_chksum_driver = NULL;
3159                         goto failed_mount;
3160                 }
3161         }
3162
3163         /* Check superblock checksum */
3164         if (!ext4_superblock_csum_verify(sb, es)) {
3165                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3166                          "invalid superblock checksum.  Run e2fsck?");
3167                 silent = 1;
3168                 goto cantfind_ext4;
3169         }
3170
3171         /* Precompute checksum seed for all metadata */
3172         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3173                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
3174                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3175                                                sizeof(es->s_uuid));
3176
3177         /* Set defaults before we parse the mount options */
3178         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3179         set_opt(sb, INIT_INODE_TABLE);
3180         if (def_mount_opts & EXT4_DEFM_DEBUG)
3181                 set_opt(sb, DEBUG);
3182         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3183                 set_opt(sb, GRPID);
3184         if (def_mount_opts & EXT4_DEFM_UID16)
3185                 set_opt(sb, NO_UID32);
3186         /* xattr user namespace & acls are now defaulted on */
3187 #ifdef CONFIG_EXT4_FS_XATTR
3188         set_opt(sb, XATTR_USER);
3189 #endif
3190 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3191         set_opt(sb, POSIX_ACL);
3192 #endif
3193         set_opt(sb, MBLK_IO_SUBMIT);
3194         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3195                 set_opt(sb, JOURNAL_DATA);
3196         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3197                 set_opt(sb, ORDERED_DATA);
3198         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3199                 set_opt(sb, WRITEBACK_DATA);
3200
3201         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3202                 set_opt(sb, ERRORS_PANIC);
3203         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3204                 set_opt(sb, ERRORS_CONT);
3205         else
3206                 set_opt(sb, ERRORS_RO);
3207         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3208                 set_opt(sb, BLOCK_VALIDITY);
3209         if (def_mount_opts & EXT4_DEFM_DISCARD)
3210                 set_opt(sb, DISCARD);
3211
3212         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
3213         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
3214         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3215         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3216         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3217
3218         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3219                 set_opt(sb, BARRIER);
3220
3221         /*
3222          * enable delayed allocation by default
3223          * Use -o nodelalloc to turn it off
3224          */
3225         if (!IS_EXT3_SB(sb) &&
3226             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3227                 set_opt(sb, DELALLOC);
3228
3229         /*
3230          * set default s_li_wait_mult for lazyinit, for the case there is
3231          * no mount option specified.
3232          */
3233         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3234
3235         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3236                            &journal_devnum, &journal_ioprio, 0)) {
3237                 ext4_msg(sb, KERN_WARNING,
3238                          "failed to parse options in superblock: %s",
3239                          sbi->s_es->s_mount_opts);
3240         }
3241         sbi->s_def_mount_opt = sbi->s_mount_opt;
3242         if (!parse_options((char *) data, sb, &journal_devnum,
3243                            &journal_ioprio, 0))
3244                 goto failed_mount;
3245
3246         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3247                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3248                             "with data=journal disables delayed "
3249                             "allocation and O_DIRECT support!\n");
3250                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3251                         ext4_msg(sb, KERN_ERR, "can't mount with "
3252                                  "both data=journal and delalloc");
3253                         goto failed_mount;
3254                 }
3255                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3256                         ext4_msg(sb, KERN_ERR, "can't mount with "
3257                                  "both data=journal and delalloc");
3258                         goto failed_mount;
3259                 }
3260                 if (test_opt(sb, DELALLOC))
3261                         clear_opt(sb, DELALLOC);
3262         }
3263
3264         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3265         if (test_opt(sb, DIOREAD_NOLOCK)) {
3266                 if (blocksize < PAGE_SIZE) {
3267                         ext4_msg(sb, KERN_ERR, "can't mount with "
3268                                  "dioread_nolock if block size != PAGE_SIZE");
3269                         goto failed_mount;
3270                 }
3271         }
3272
3273         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3274                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3275
3276         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3277             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3278              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3279              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3280                 ext4_msg(sb, KERN_WARNING,
3281                        "feature flags set on rev 0 fs, "
3282                        "running e2fsck is recommended");
3283
3284         if (IS_EXT2_SB(sb)) {
3285                 if (ext2_feature_set_ok(sb))
3286                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3287                                  "using the ext4 subsystem");
3288                 else {
3289                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3290                                  "to feature incompatibilities");
3291                         goto failed_mount;
3292                 }
3293         }
3294
3295         if (IS_EXT3_SB(sb)) {
3296                 if (ext3_feature_set_ok(sb))
3297                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3298                                  "using the ext4 subsystem");
3299                 else {
3300                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3301                                  "to feature incompatibilities");
3302                         goto failed_mount;
3303                 }
3304         }
3305
3306         /*
3307          * Check feature flags regardless of the revision level, since we
3308          * previously didn't change the revision level when setting the flags,
3309          * so there is a chance incompat flags are set on a rev 0 filesystem.
3310          */
3311         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3312                 goto failed_mount;
3313
3314         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3315             blocksize > EXT4_MAX_BLOCK_SIZE) {
3316                 ext4_msg(sb, KERN_ERR,
3317                        "Unsupported filesystem blocksize %d", blocksize);
3318                 goto failed_mount;
3319         }
3320
3321         if (sb->s_blocksize != blocksize) {
3322                 /* Validate the filesystem blocksize */
3323                 if (!sb_set_blocksize(sb, blocksize)) {
3324                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3325                                         blocksize);
3326                         goto failed_mount;
3327                 }
3328
3329                 brelse(bh);
3330                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3331                 offset = do_div(logical_sb_block, blocksize);
3332                 bh = sb_bread(sb, logical_sb_block);
3333                 if (!bh) {
3334                         ext4_msg(sb, KERN_ERR,
3335                                "Can't read superblock on 2nd try");
3336                         goto failed_mount;
3337                 }
3338                 es = (struct ext4_super_block *)(bh->b_data + offset);
3339                 sbi->s_es = es;
3340                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3341                         ext4_msg(sb, KERN_ERR,
3342                                "Magic mismatch, very weird!");
3343                         goto failed_mount;
3344                 }
3345         }
3346
3347         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3348                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3349         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3350                                                       has_huge_files);
3351         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3352
3353         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3354                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3355                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3356         } else {
3357                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3358                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3359                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3360                     (!is_power_of_2(sbi->s_inode_size)) ||
3361                     (sbi->s_inode_size > blocksize)) {
3362                         ext4_msg(sb, KERN_ERR,
3363                                "unsupported inode size: %d",
3364                                sbi->s_inode_size);
3365                         goto failed_mount;
3366                 }
3367                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3368                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3369         }
3370
3371         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3372         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3373                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3374                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3375                     !is_power_of_2(sbi->s_desc_size)) {
3376                         ext4_msg(sb, KERN_ERR,
3377                                "unsupported descriptor size %lu",
3378                                sbi->s_desc_size);
3379                         goto failed_mount;
3380                 }
3381         } else
3382                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3383
3384         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3385         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3386         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3387                 goto cantfind_ext4;
3388
3389         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3390         if (sbi->s_inodes_per_block == 0)
3391                 goto cantfind_ext4;
3392         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3393                                         sbi->s_inodes_per_block;
3394         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3395         sbi->s_sbh = bh;
3396         sbi->s_mount_state = le16_to_cpu(es->s_state);
3397         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3398         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3399
3400         for (i = 0; i < 4; i++)
3401                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3402         sbi->s_def_hash_version = es->s_def_hash_version;
3403         i = le32_to_cpu(es->s_flags);
3404         if (i & EXT2_FLAGS_UNSIGNED_HASH)
3405                 sbi->s_hash_unsigned = 3;
3406         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3407 #ifdef __CHAR_UNSIGNED__
3408                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3409                 sbi->s_hash_unsigned = 3;
3410 #else
3411                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3412 #endif
3413         }
3414
3415         /* Handle clustersize */
3416         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3417         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3418                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3419         if (has_bigalloc) {
3420                 if (clustersize < blocksize) {
3421                         ext4_msg(sb, KERN_ERR,
3422                                  "cluster size (%d) smaller than "
3423                                  "block size (%d)", clustersize, blocksize);
3424                         goto failed_mount;
3425                 }
3426                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3427                         le32_to_cpu(es->s_log_block_size);
3428                 sbi->s_clusters_per_group =
3429                         le32_to_cpu(es->s_clusters_per_group);
3430                 if (sbi->s_clusters_per_group > blocksize * 8) {
3431                         ext4_msg(sb, KERN_ERR,
3432                                  "#clusters per group too big: %lu",
3433                                  sbi->s_clusters_per_group);
3434                         goto failed_mount;
3435                 }
3436                 if (sbi->s_blocks_per_group !=
3437                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3438                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3439                                  "clusters per group (%lu) inconsistent",
3440                                  sbi->s_blocks_per_group,
3441                                  sbi->s_clusters_per_group);
3442                         goto failed_mount;
3443                 }
3444         } else {
3445                 if (clustersize != blocksize) {
3446                         ext4_warning(sb, "fragment/cluster size (%d) != "
3447                                      "block size (%d)", clustersize,
3448                                      blocksize);
3449                         clustersize = blocksize;
3450                 }
3451                 if (sbi->s_blocks_per_group > blocksize * 8) {
3452                         ext4_msg(sb, KERN_ERR,
3453                                  "#blocks per group too big: %lu",
3454                                  sbi->s_blocks_per_group);
3455                         goto failed_mount;
3456                 }
3457                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3458                 sbi->s_cluster_bits = 0;
3459         }
3460         sbi->s_cluster_ratio = clustersize / blocksize;
3461
3462         if (sbi->s_inodes_per_group > blocksize * 8) {
3463                 ext4_msg(sb, KERN_ERR,
3464                        "#inodes per group too big: %lu",
3465                        sbi->s_inodes_per_group);
3466                 goto failed_mount;
3467         }
3468
3469         /*
3470          * Test whether we have more sectors than will fit in sector_t,
3471          * and whether the max offset is addressable by the page cache.
3472          */
3473         err = generic_check_addressable(sb->s_blocksize_bits,
3474                                         ext4_blocks_count(es));
3475         if (err) {
3476                 ext4_msg(sb, KERN_ERR, "filesystem"
3477                          " too large to mount safely on this system");
3478                 if (sizeof(sector_t) < 8)
3479                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3480                 ret = err;
3481                 goto failed_mount;
3482         }
3483
3484         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3485                 goto cantfind_ext4;
3486
3487         /* check blocks count against device size */
3488         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3489         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3490                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3491                        "exceeds size of device (%llu blocks)",
3492                        ext4_blocks_count(es), blocks_count);
3493                 goto failed_mount;
3494         }
3495
3496         /*
3497          * It makes no sense for the first data block to be beyond the end
3498          * of the filesystem.
3499          */
3500         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3501                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3502                          "block %u is beyond end of filesystem (%llu)",
3503                          le32_to_cpu(es->s_first_data_block),
3504                          ext4_blocks_count(es));
3505                 goto failed_mount;
3506         }
3507         blocks_count = (ext4_blocks_count(es) -
3508                         le32_to_cpu(es->s_first_data_block) +
3509                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3510         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3511         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3512                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3513                        "(block count %llu, first data block %u, "
3514                        "blocks per group %lu)", sbi->s_groups_count,
3515                        ext4_blocks_count(es),
3516                        le32_to_cpu(es->s_first_data_block),
3517                        EXT4_BLOCKS_PER_GROUP(sb));
3518                 goto failed_mount;
3519         }
3520         sbi->s_groups_count = blocks_count;
3521         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3522                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3523         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3524                    EXT4_DESC_PER_BLOCK(sb);
3525         sbi->s_group_desc = ext4_kvmalloc(db_count *
3526                                           sizeof(struct buffer_head *),
3527                                           GFP_KERNEL);
3528         if (sbi->s_group_desc == NULL) {
3529                 ext4_msg(sb, KERN_ERR, "not enough memory");
3530                 ret = -ENOMEM;
3531                 goto failed_mount;
3532         }
3533
3534         if (ext4_proc_root)
3535                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3536
3537         if (sbi->s_proc)
3538                 proc_create_data("options", S_IRUGO, sbi->s_proc,
3539                                  &ext4_seq_options_fops, sb);
3540
3541         bgl_lock_init(sbi->s_blockgroup_lock);
3542
3543         for (i = 0; i < db_count; i++) {
3544                 block = descriptor_loc(sb, logical_sb_block, i);
3545                 sbi->s_group_desc[i] = sb_bread(sb, block);
3546                 if (!sbi->s_group_desc[i]) {
3547                         ext4_msg(sb, KERN_ERR,
3548                                "can't read group descriptor %d", i);
3549                         db_count = i;
3550                         goto failed_mount2;
3551                 }
3552         }
3553         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3554                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3555                 goto failed_mount2;
3556         }
3557         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3558                 if (!ext4_fill_flex_info(sb)) {
3559                         ext4_msg(sb, KERN_ERR,
3560                                "unable to initialize "
3561                                "flex_bg meta info!");
3562                         goto failed_mount2;
3563                 }
3564
3565         sbi->s_gdb_count = db_count;
3566         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3567         spin_lock_init(&sbi->s_next_gen_lock);
3568
3569         init_timer(&sbi->s_err_report);
3570         sbi->s_err_report.function = print_daily_error_info;
3571         sbi->s_err_report.data = (unsigned long) sb;
3572
3573         err = percpu_counter_init(&sbi->s_freeclusters_counter,
3574                         ext4_count_free_clusters(sb));
3575         if (!err) {
3576                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
3577                                 ext4_count_free_inodes(sb));
3578         }
3579         if (!err) {
3580                 err = percpu_counter_init(&sbi->s_dirs_counter,
3581                                 ext4_count_dirs(sb));
3582         }
3583         if (!err) {
3584                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0);
3585         }
3586         if (err) {
3587                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3588                 ret = err;
3589                 goto failed_mount3;
3590         }
3591
3592         sbi->s_stripe = ext4_get_stripe_size(sbi);
3593         sbi->s_max_writeback_mb_bump = 128;
3594
3595         /*
3596          * set up enough so that it can read an inode
3597          */
3598         if (!test_opt(sb, NOLOAD) &&
3599             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3600                 sb->s_op = &ext4_sops;
3601         else
3602                 sb->s_op = &ext4_nojournal_sops;
3603         sb->s_export_op = &ext4_export_ops;
3604         sb->s_xattr = ext4_xattr_handlers;
3605 #ifdef CONFIG_QUOTA
3606         sb->s_qcop = &ext4_qctl_operations;
3607         sb->dq_op = &ext4_quota_operations;
3608 #endif
3609         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3610
3611         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3612         mutex_init(&sbi->s_orphan_lock);
3613         sbi->s_resize_flags = 0;
3614
3615         sb->s_root = NULL;
3616
3617         needs_recovery = (es->s_last_orphan != 0 ||
3618                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3619                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3620
3621         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3622             !(sb->s_flags & MS_RDONLY))
3623                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3624                         goto failed_mount3;
3625
3626         /*
3627          * The first inode we look at is the journal inode.  Don't try
3628          * root first: it may be modified in the journal!
3629          */
3630         if (!test_opt(sb, NOLOAD) &&
3631             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3632                 if (ext4_load_journal(sb, es, journal_devnum))
3633                         goto failed_mount3;
3634         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3635               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3636                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3637                        "suppressed and not mounted read-only");
3638                 goto failed_mount_wq;
3639         } else {
3640                 clear_opt(sb, DATA_FLAGS);
3641                 sbi->s_journal = NULL;
3642                 needs_recovery = 0;
3643                 goto no_journal;
3644         }
3645
3646         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) &&
3647             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3648                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3649                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3650                 goto failed_mount_wq;
3651         }
3652
3653         if (!set_journal_csum_feature_set(sb)) {
3654                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
3655                          "feature set");
3656                 goto failed_mount_wq;
3657         }
3658
3659         /* We have now updated the journal if required, so we can
3660          * validate the data journaling mode. */
3661         switch (test_opt(sb, DATA_FLAGS)) {
3662         case 0:
3663                 /* No mode set, assume a default based on the journal
3664                  * capabilities: ORDERED_DATA if the journal can
3665                  * cope, else JOURNAL_DATA
3666                  */
3667                 if (jbd2_journal_check_available_features
3668                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3669                         set_opt(sb, ORDERED_DATA);
3670                 else
3671                         set_opt(sb, JOURNAL_DATA);
3672                 break;
3673
3674         case EXT4_MOUNT_ORDERED_DATA:
3675         case EXT4_MOUNT_WRITEBACK_DATA:
3676                 if (!jbd2_journal_check_available_features
3677                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3678                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3679                                "requested data journaling mode");
3680                         goto failed_mount_wq;
3681                 }
3682         default:
3683                 break;
3684         }
3685         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3686
3687         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
3688
3689         /*
3690          * The journal may have updated the bg summary counts, so we
3691          * need to update the global counters.
3692          */
3693         percpu_counter_set(&sbi->s_freeclusters_counter,
3694                            ext4_count_free_clusters(sb));
3695         percpu_counter_set(&sbi->s_freeinodes_counter,
3696                            ext4_count_free_inodes(sb));
3697         percpu_counter_set(&sbi->s_dirs_counter,
3698                            ext4_count_dirs(sb));
3699         percpu_counter_set(&sbi->s_dirtyclusters_counter, 0);
3700
3701 no_journal:
3702         /*
3703          * The maximum number of concurrent works can be high and
3704          * concurrency isn't really necessary.  Limit it to 1.
3705          */
3706         EXT4_SB(sb)->dio_unwritten_wq =
3707                 alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
3708         if (!EXT4_SB(sb)->dio_unwritten_wq) {
3709                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
3710                 goto failed_mount_wq;
3711         }
3712
3713         /*
3714          * The jbd2_journal_load will have done any necessary log recovery,
3715          * so we can safely mount the rest of the filesystem now.
3716          */
3717
3718         root = ext4_iget(sb, EXT4_ROOT_INO);
3719         if (IS_ERR(root)) {
3720                 ext4_msg(sb, KERN_ERR, "get root inode failed");
3721                 ret = PTR_ERR(root);
3722                 root = NULL;
3723                 goto failed_mount4;
3724         }
3725         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3726                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3727                 iput(root);
3728                 goto failed_mount4;
3729         }
3730         sb->s_root = d_make_root(root);
3731         if (!sb->s_root) {
3732                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
3733                 ret = -ENOMEM;
3734                 goto failed_mount4;
3735         }
3736
3737         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
3738                 sb->s_flags |= MS_RDONLY;
3739
3740         /* determine the minimum size of new large inodes, if present */
3741         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3742                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3743                                                      EXT4_GOOD_OLD_INODE_SIZE;
3744                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3745                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
3746                         if (sbi->s_want_extra_isize <
3747                             le16_to_cpu(es->s_want_extra_isize))
3748                                 sbi->s_want_extra_isize =
3749                                         le16_to_cpu(es->s_want_extra_isize);
3750                         if (sbi->s_want_extra_isize <
3751                             le16_to_cpu(es->s_min_extra_isize))
3752                                 sbi->s_want_extra_isize =
3753                                         le16_to_cpu(es->s_min_extra_isize);
3754                 }
3755         }
3756         /* Check if enough inode space is available */
3757         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3758                                                         sbi->s_inode_size) {
3759                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3760                                                        EXT4_GOOD_OLD_INODE_SIZE;
3761                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
3762                          "available");
3763         }
3764
3765         err = ext4_setup_system_zone(sb);
3766         if (err) {
3767                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3768                          "zone (%d)", err);
3769                 goto failed_mount4a;
3770         }
3771
3772         ext4_ext_init(sb);
3773         err = ext4_mb_init(sb);
3774         if (err) {
3775                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3776                          err);
3777                 goto failed_mount5;
3778         }
3779
3780         err = ext4_register_li_request(sb, first_not_zeroed);
3781         if (err)
3782                 goto failed_mount6;
3783
3784         sbi->s_kobj.kset = ext4_kset;
3785         init_completion(&sbi->s_kobj_unregister);
3786         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3787                                    "%s", sb->s_id);
3788         if (err)
3789                 goto failed_mount7;
3790
3791         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3792         ext4_orphan_cleanup(sb, es);
3793         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3794         if (needs_recovery) {
3795                 ext4_msg(sb, KERN_INFO, "recovery complete");
3796                 ext4_mark_recovery_complete(sb, es);
3797         }
3798         if (EXT4_SB(sb)->s_journal) {
3799                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3800                         descr = " journalled data mode";
3801                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3802                         descr = " ordered data mode";
3803                 else
3804                         descr = " writeback data mode";
3805         } else
3806                 descr = "out journal";
3807
3808         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3809                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
3810                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
3811
3812         if (es->s_error_count)
3813                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
3814
3815         kfree(orig_data);
3816         return 0;
3817
3818 cantfind_ext4:
3819         if (!silent)
3820                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3821         goto failed_mount;
3822
3823 failed_mount7:
3824         ext4_unregister_li_request(sb);
3825 failed_mount6:
3826         ext4_mb_release(sb);
3827 failed_mount5:
3828         ext4_ext_release(sb);
3829         ext4_release_system_zone(sb);
3830 failed_mount4a:
3831         dput(sb->s_root);
3832         sb->s_root = NULL;
3833 failed_mount4:
3834         ext4_msg(sb, KERN_ERR, "mount failed");
3835         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
3836 failed_mount_wq:
3837         if (sbi->s_journal) {
3838                 jbd2_journal_destroy(sbi->s_journal);
3839                 sbi->s_journal = NULL;
3840         }
3841 failed_mount3:
3842         del_timer(&sbi->s_err_report);
3843         if (sbi->s_flex_groups)
3844                 ext4_kvfree(sbi->s_flex_groups);
3845         percpu_counter_destroy(&sbi->s_freeclusters_counter);
3846         percpu_counter_destroy(&sbi->s_freeinodes_counter);
3847         percpu_counter_destroy(&sbi->s_dirs_counter);
3848         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
3849         if (sbi->s_mmp_tsk)
3850                 kthread_stop(sbi->s_mmp_tsk);
3851 failed_mount2:
3852         for (i = 0; i < db_count; i++)
3853                 brelse(sbi->s_group_desc[i]);
3854         ext4_kvfree(sbi->s_group_desc);
3855 failed_mount:
3856         if (sbi->s_chksum_driver)
3857                 crypto_free_shash(sbi->s_chksum_driver);
3858         if (sbi->s_proc) {
3859                 remove_proc_entry("options", sbi->s_proc);
3860                 remove_proc_entry(sb->s_id, ext4_proc_root);
3861         }
3862 #ifdef CONFIG_QUOTA
3863         for (i = 0; i < MAXQUOTAS; i++)
3864                 kfree(sbi->s_qf_names[i]);
3865 #endif
3866         ext4_blkdev_remove(sbi);
3867         brelse(bh);
3868 out_fail:
3869         sb->s_fs_info = NULL;
3870         kfree(sbi->s_blockgroup_lock);
3871         kfree(sbi);
3872 out_free_orig:
3873         kfree(orig_data);
3874         return ret;
3875 }
3876
3877 /*
3878  * Setup any per-fs journal parameters now.  We'll do this both on
3879  * initial mount, once the journal has been initialised but before we've
3880  * done any recovery; and again on any subsequent remount.
3881  */
3882 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
3883 {
3884         struct ext4_sb_info *sbi = EXT4_SB(sb);
3885
3886         journal->j_commit_interval = sbi->s_commit_interval;
3887         journal->j_min_batch_time = sbi->s_min_batch_time;
3888         journal->j_max_batch_time = sbi->s_max_batch_time;
3889
3890         write_lock(&journal->j_state_lock);
3891         if (test_opt(sb, BARRIER))
3892                 journal->j_flags |= JBD2_BARRIER;
3893         else
3894                 journal->j_flags &= ~JBD2_BARRIER;
3895         if (test_opt(sb, DATA_ERR_ABORT))
3896                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3897         else
3898                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3899         write_unlock(&journal->j_state_lock);
3900 }
3901
3902 static journal_t *ext4_get_journal(struct super_block *sb,
3903                                    unsigned int journal_inum)
3904 {
3905         struct inode *journal_inode;
3906         journal_t *journal;
3907
3908         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3909
3910         /* First, test for the existence of a valid inode on disk.  Bad
3911          * things happen if we iget() an unused inode, as the subsequent
3912          * iput() will try to delete it. */
3913
3914         journal_inode = ext4_iget(sb, journal_inum);
3915         if (IS_ERR(journal_inode)) {
3916                 ext4_msg(sb, KERN_ERR, "no journal found");
3917                 return NULL;
3918         }
3919         if (!journal_inode->i_nlink) {
3920                 make_bad_inode(journal_inode);
3921                 iput(journal_inode);
3922                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3923                 return NULL;
3924         }
3925
3926         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3927                   journal_inode, journal_inode->i_size);
3928         if (!S_ISREG(journal_inode->i_mode)) {
3929                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3930                 iput(journal_inode);
3931                 return NULL;
3932         }
3933
3934         journal = jbd2_journal_init_inode(journal_inode);
3935         if (!journal) {
3936                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3937                 iput(journal_inode);
3938                 return NULL;
3939         }
3940         journal->j_private = sb;
3941         ext4_init_journal_params(sb, journal);
3942         return journal;
3943 }
3944
3945 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3946                                        dev_t j_dev)
3947 {
3948         struct buffer_head *bh;
3949         journal_t *journal;
3950         ext4_fsblk_t start;
3951         ext4_fsblk_t len;
3952         int hblock, blocksize;
3953         ext4_fsblk_t sb_block;
3954         unsigned long offset;
3955         struct ext4_super_block *es;
3956         struct block_device *bdev;
3957
3958         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3959
3960         bdev = ext4_blkdev_get(j_dev, sb);
3961         if (bdev == NULL)
3962                 return NULL;
3963
3964         blocksize = sb->s_blocksize;
3965         hblock = bdev_logical_block_size(bdev);
3966         if (blocksize < hblock) {
3967                 ext4_msg(sb, KERN_ERR,
3968                         "blocksize too small for journal device");
3969                 goto out_bdev;
3970         }
3971
3972         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3973         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3974         set_blocksize(bdev, blocksize);
3975         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3976                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3977                        "external journal");
3978                 goto out_bdev;
3979         }
3980
3981         es = (struct ext4_super_block *) (bh->b_data + offset);
3982         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3983             !(le32_to_cpu(es->s_feature_incompat) &
3984               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3985                 ext4_msg(sb, KERN_ERR, "external journal has "
3986                                         "bad superblock");
3987                 brelse(bh);
3988                 goto out_bdev;
3989         }
3990
3991         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3992                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3993                 brelse(bh);
3994                 goto out_bdev;
3995         }
3996
3997         len = ext4_blocks_count(es);
3998         start = sb_block + 1;
3999         brelse(bh);     /* we're done with the superblock */
4000
4001         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4002                                         start, len, blocksize);
4003         if (!journal) {
4004                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4005                 goto out_bdev;
4006         }
4007         journal->j_private = sb;
4008         ll_rw_block(READ, 1, &journal->j_sb_buffer);
4009         wait_on_buffer(journal->j_sb_buffer);
4010         if (!buffer_uptodate(journal->j_sb_buffer)) {
4011                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4012                 goto out_journal;
4013         }
4014         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4015                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4016                                         "user (unsupported) - %d",
4017                         be32_to_cpu(journal->j_superblock->s_nr_users));
4018                 goto out_journal;
4019         }
4020         EXT4_SB(sb)->journal_bdev = bdev;
4021         ext4_init_journal_params(sb, journal);
4022         return journal;
4023
4024 out_journal:
4025         jbd2_journal_destroy(journal);
4026 out_bdev:
4027         ext4_blkdev_put(bdev);
4028         return NULL;
4029 }
4030
4031 static int ext4_load_journal(struct super_block *sb,
4032                              struct ext4_super_block *es,
4033                              unsigned long journal_devnum)
4034 {
4035         journal_t *journal;
4036         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4037         dev_t journal_dev;
4038         int err = 0;
4039         int really_read_only;
4040
4041         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4042
4043         if (journal_devnum &&
4044             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4045                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4046                         "numbers have changed");
4047                 journal_dev = new_decode_dev(journal_devnum);
4048         } else
4049                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4050
4051         really_read_only = bdev_read_only(sb->s_bdev);
4052
4053         /*
4054          * Are we loading a blank journal or performing recovery after a
4055          * crash?  For recovery, we need to check in advance whether we
4056          * can get read-write access to the device.
4057          */
4058         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4059                 if (sb->s_flags & MS_RDONLY) {
4060                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4061                                         "required on readonly filesystem");
4062                         if (really_read_only) {
4063                                 ext4_msg(sb, KERN_ERR, "write access "
4064                                         "unavailable, cannot proceed");
4065                                 return -EROFS;
4066                         }
4067                         ext4_msg(sb, KERN_INFO, "write access will "
4068                                "be enabled during recovery");
4069                 }
4070         }
4071
4072         if (journal_inum && journal_dev) {
4073                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4074                        "and inode journals!");
4075                 return -EINVAL;
4076         }
4077
4078         if (journal_inum) {
4079                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4080                         return -EINVAL;
4081         } else {
4082                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4083                         return -EINVAL;
4084         }
4085
4086         if (!(journal->j_flags & JBD2_BARRIER))
4087                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4088
4089         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4090                 err = jbd2_journal_wipe(journal, !really_read_only);
4091         if (!err) {
4092                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4093                 if (save)
4094                         memcpy(save, ((char *) es) +
4095                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4096                 err = jbd2_journal_load(journal);
4097                 if (save)
4098                         memcpy(((char *) es) + EXT4_S_ERR_START,
4099                                save, EXT4_S_ERR_LEN);
4100                 kfree(save);
4101         }
4102
4103         if (err) {
4104                 ext4_msg(sb, KERN_ERR, "error loading journal");
4105                 jbd2_journal_destroy(journal);
4106                 return err;
4107         }
4108
4109         EXT4_SB(sb)->s_journal = journal;
4110         ext4_clear_journal_err(sb, es);
4111
4112         if (!really_read_only && journal_devnum &&
4113             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4114                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4115
4116                 /* Make sure we flush the recovery flag to disk. */
4117                 ext4_commit_super(sb, 1);
4118         }
4119
4120         return 0;
4121 }
4122
4123 static int ext4_commit_super(struct super_block *sb, int sync)
4124 {
4125         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4126         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4127         int error = 0;
4128
4129         if (!sbh || block_device_ejected(sb))
4130                 return error;
4131         if (buffer_write_io_error(sbh)) {
4132                 /*
4133                  * Oh, dear.  A previous attempt to write the
4134                  * superblock failed.  This could happen because the
4135                  * USB device was yanked out.  Or it could happen to
4136                  * be a transient write error and maybe the block will
4137                  * be remapped.  Nothing we can do but to retry the
4138                  * write and hope for the best.
4139                  */
4140                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4141                        "superblock detected");
4142                 clear_buffer_write_io_error(sbh);
4143                 set_buffer_uptodate(sbh);
4144         }
4145         /*
4146          * If the file system is mounted read-only, don't update the
4147          * superblock write time.  This avoids updating the superblock
4148          * write time when we are mounting the root file system
4149          * read/only but we need to replay the journal; at that point,
4150          * for people who are east of GMT and who make their clock
4151          * tick in localtime for Windows bug-for-bug compatibility,
4152          * the clock is set in the future, and this will cause e2fsck
4153          * to complain and force a full file system check.
4154          */
4155         if (!(sb->s_flags & MS_RDONLY))
4156                 es->s_wtime = cpu_to_le32(get_seconds());
4157         if (sb->s_bdev->bd_part)
4158                 es->s_kbytes_written =
4159                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4160                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4161                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4162         else
4163                 es->s_kbytes_written =
4164                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4165         ext4_free_blocks_count_set(es,
4166                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4167                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4168         es->s_free_inodes_count =
4169                 cpu_to_le32(percpu_counter_sum_positive(
4170                                 &EXT4_SB(sb)->s_freeinodes_counter));
4171         sb->s_dirt = 0;
4172         BUFFER_TRACE(sbh, "marking dirty");
4173         ext4_superblock_csum_set(sb, es);
4174         mark_buffer_dirty(sbh);
4175         if (sync) {
4176                 error = sync_dirty_buffer(sbh);
4177                 if (error)
4178                         return error;
4179
4180                 error = buffer_write_io_error(sbh);
4181                 if (error) {
4182                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4183                                "superblock");
4184                         clear_buffer_write_io_error(sbh);
4185                         set_buffer_uptodate(sbh);
4186                 }
4187         }
4188         return error;
4189 }
4190
4191 /*
4192  * Have we just finished recovery?  If so, and if we are mounting (or
4193  * remounting) the filesystem readonly, then we will end up with a
4194  * consistent fs on disk.  Record that fact.
4195  */
4196 static void ext4_mark_recovery_complete(struct super_block *sb,
4197                                         struct ext4_super_block *es)
4198 {
4199         journal_t *journal = EXT4_SB(sb)->s_journal;
4200
4201         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4202                 BUG_ON(journal != NULL);
4203                 return;
4204         }
4205         jbd2_journal_lock_updates(journal);
4206         if (jbd2_journal_flush(journal) < 0)
4207                 goto out;
4208
4209         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4210             sb->s_flags & MS_RDONLY) {
4211                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4212                 ext4_commit_super(sb, 1);
4213         }
4214
4215 out:
4216         jbd2_journal_unlock_updates(journal);
4217 }
4218
4219 /*
4220  * If we are mounting (or read-write remounting) a filesystem whose journal
4221  * has recorded an error from a previous lifetime, move that error to the
4222  * main filesystem now.
4223  */
4224 static void ext4_clear_journal_err(struct super_block *sb,
4225                                    struct ext4_super_block *es)
4226 {
4227         journal_t *journal;
4228         int j_errno;
4229         const char *errstr;
4230
4231         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4232
4233         journal = EXT4_SB(sb)->s_journal;
4234
4235         /*
4236          * Now check for any error status which may have been recorded in the
4237          * journal by a prior ext4_error() or ext4_abort()
4238          */
4239
4240         j_errno = jbd2_journal_errno(journal);
4241         if (j_errno) {
4242                 char nbuf[16];
4243
4244                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4245                 ext4_warning(sb, "Filesystem error recorded "
4246                              "from previous mount: %s", errstr);
4247                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4248
4249                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4250                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4251                 ext4_commit_super(sb, 1);
4252
4253                 jbd2_journal_clear_err(journal);
4254         }
4255 }
4256
4257 /*
4258  * Force the running and committing transactions to commit,
4259  * and wait on the commit.
4260  */
4261 int ext4_force_commit(struct super_block *sb)
4262 {
4263         journal_t *journal;
4264         int ret = 0;
4265
4266         if (sb->s_flags & MS_RDONLY)
4267                 return 0;
4268
4269         journal = EXT4_SB(sb)->s_journal;
4270         if (journal) {
4271                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
4272                 ret = ext4_journal_force_commit(journal);
4273         }
4274
4275         return ret;
4276 }
4277
4278 static void ext4_write_super(struct super_block *sb)
4279 {
4280         lock_super(sb);
4281         ext4_commit_super(sb, 1);
4282         unlock_super(sb);
4283 }
4284
4285 static int ext4_sync_fs(struct super_block *sb, int wait)
4286 {
4287         int ret = 0;
4288         tid_t target;
4289         struct ext4_sb_info *sbi = EXT4_SB(sb);
4290
4291         trace_ext4_sync_fs(sb, wait);
4292         flush_workqueue(sbi->dio_unwritten_wq);
4293         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4294                 if (wait)
4295                         jbd2_log_wait_commit(sbi->s_journal, target);
4296         }
4297         return ret;
4298 }
4299
4300 /*
4301  * LVM calls this function before a (read-only) snapshot is created.  This
4302  * gives us a chance to flush the journal completely and mark the fs clean.
4303  *
4304  * Note that only this function cannot bring a filesystem to be in a clean
4305  * state independently, because ext4 prevents a new handle from being started
4306  * by @sb->s_frozen, which stays in an upper layer.  It thus needs help from
4307  * the upper layer.
4308  */
4309 static int ext4_freeze(struct super_block *sb)
4310 {
4311         int error = 0;
4312         journal_t *journal;
4313
4314         if (sb->s_flags & MS_RDONLY)
4315                 return 0;
4316
4317         journal = EXT4_SB(sb)->s_journal;
4318
4319         /* Now we set up the journal barrier. */
4320         jbd2_journal_lock_updates(journal);
4321
4322         /*
4323          * Don't clear the needs_recovery flag if we failed to flush
4324          * the journal.
4325          */
4326         error = jbd2_journal_flush(journal);
4327         if (error < 0)
4328                 goto out;
4329
4330         /* Journal blocked and flushed, clear needs_recovery flag. */
4331         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4332         error = ext4_commit_super(sb, 1);
4333 out:
4334         /* we rely on s_frozen to stop further updates */
4335         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4336         return error;
4337 }
4338
4339 /*
4340  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4341  * flag here, even though the filesystem is not technically dirty yet.
4342  */
4343 static int ext4_unfreeze(struct super_block *sb)
4344 {
4345         if (sb->s_flags & MS_RDONLY)
4346                 return 0;
4347
4348         lock_super(sb);
4349         /* Reset the needs_recovery flag before the fs is unlocked. */
4350         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4351         ext4_commit_super(sb, 1);
4352         unlock_super(sb);
4353         return 0;
4354 }
4355
4356 /*
4357  * Structure to save mount options for ext4_remount's benefit
4358  */
4359 struct ext4_mount_options {
4360         unsigned long s_mount_opt;
4361         unsigned long s_mount_opt2;
4362         uid_t s_resuid;
4363         gid_t s_resgid;
4364         unsigned long s_commit_interval;
4365         u32 s_min_batch_time, s_max_batch_time;
4366 #ifdef CONFIG_QUOTA
4367         int s_jquota_fmt;
4368         char *s_qf_names[MAXQUOTAS];
4369 #endif
4370 };
4371
4372 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4373 {
4374         struct ext4_super_block *es;
4375         struct ext4_sb_info *sbi = EXT4_SB(sb);
4376         unsigned long old_sb_flags;
4377         struct ext4_mount_options old_opts;
4378         int enable_quota = 0;
4379         ext4_group_t g;
4380         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4381         int err = 0;
4382 #ifdef CONFIG_QUOTA
4383         int i;
4384 #endif
4385         char *orig_data = kstrdup(data, GFP_KERNEL);
4386
4387         /* Store the original options */
4388         lock_super(sb);
4389         old_sb_flags = sb->s_flags;
4390         old_opts.s_mount_opt = sbi->s_mount_opt;
4391         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4392         old_opts.s_resuid = sbi->s_resuid;
4393         old_opts.s_resgid = sbi->s_resgid;
4394         old_opts.s_commit_interval = sbi->s_commit_interval;
4395         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4396         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4397 #ifdef CONFIG_QUOTA
4398         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4399         for (i = 0; i < MAXQUOTAS; i++)
4400                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
4401 #endif
4402         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4403                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4404
4405         /*
4406          * Allow the "check" option to be passed as a remount option.
4407          */
4408         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4409                 err = -EINVAL;
4410                 goto restore_opts;
4411         }
4412
4413         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4414                 ext4_abort(sb, "Abort forced by user");
4415
4416         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4417                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4418
4419         es = sbi->s_es;
4420
4421         if (sbi->s_journal) {
4422                 ext4_init_journal_params(sb, sbi->s_journal);
4423                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4424         }
4425
4426         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4427                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4428                         err = -EROFS;
4429                         goto restore_opts;
4430                 }
4431
4432                 if (*flags & MS_RDONLY) {
4433                         err = dquot_suspend(sb, -1);
4434                         if (err < 0)
4435                                 goto restore_opts;
4436
4437                         /*
4438                          * First of all, the unconditional stuff we have to do
4439                          * to disable replay of the journal when we next remount
4440                          */
4441                         sb->s_flags |= MS_RDONLY;
4442
4443                         /*
4444                          * OK, test if we are remounting a valid rw partition
4445                          * readonly, and if so set the rdonly flag and then
4446                          * mark the partition as valid again.
4447                          */
4448                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4449                             (sbi->s_mount_state & EXT4_VALID_FS))
4450                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4451
4452                         if (sbi->s_journal)
4453                                 ext4_mark_recovery_complete(sb, es);
4454                 } else {
4455                         /* Make sure we can mount this feature set readwrite */
4456                         if (!ext4_feature_set_ok(sb, 0)) {
4457                                 err = -EROFS;
4458                                 goto restore_opts;
4459                         }
4460                         /*
4461                          * Make sure the group descriptor checksums
4462                          * are sane.  If they aren't, refuse to remount r/w.
4463                          */
4464                         for (g = 0; g < sbi->s_groups_count; g++) {
4465                                 struct ext4_group_desc *gdp =
4466                                         ext4_get_group_desc(sb, g, NULL);
4467
4468                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
4469                                         ext4_msg(sb, KERN_ERR,
4470                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4471                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4472                                                le16_to_cpu(gdp->bg_checksum));
4473                                         err = -EINVAL;
4474                                         goto restore_opts;
4475                                 }
4476                         }
4477
4478                         /*
4479                          * If we have an unprocessed orphan list hanging
4480                          * around from a previously readonly bdev mount,
4481                          * require a full umount/remount for now.
4482                          */
4483                         if (es->s_last_orphan) {
4484                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4485                                        "remount RDWR because of unprocessed "
4486                                        "orphan inode list.  Please "
4487                                        "umount/remount instead");
4488                                 err = -EINVAL;
4489                                 goto restore_opts;
4490                         }
4491
4492                         /*
4493                          * Mounting a RDONLY partition read-write, so reread
4494                          * and store the current valid flag.  (It may have
4495                          * been changed by e2fsck since we originally mounted
4496                          * the partition.)
4497                          */
4498                         if (sbi->s_journal)
4499                                 ext4_clear_journal_err(sb, es);
4500                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4501                         if (!ext4_setup_super(sb, es, 0))
4502                                 sb->s_flags &= ~MS_RDONLY;
4503                         if (EXT4_HAS_INCOMPAT_FEATURE(sb,
4504                                                      EXT4_FEATURE_INCOMPAT_MMP))
4505                                 if (ext4_multi_mount_protect(sb,
4506                                                 le64_to_cpu(es->s_mmp_block))) {
4507                                         err = -EROFS;
4508                                         goto restore_opts;
4509                                 }
4510                         enable_quota = 1;
4511                 }
4512         }
4513
4514         /*
4515          * Reinitialize lazy itable initialization thread based on
4516          * current settings
4517          */
4518         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4519                 ext4_unregister_li_request(sb);
4520         else {
4521                 ext4_group_t first_not_zeroed;
4522                 first_not_zeroed = ext4_has_uninit_itable(sb);
4523                 ext4_register_li_request(sb, first_not_zeroed);
4524         }
4525
4526         ext4_setup_system_zone(sb);
4527         if (sbi->s_journal == NULL)
4528                 ext4_commit_super(sb, 1);
4529
4530 #ifdef CONFIG_QUOTA
4531         /* Release old quota file names */
4532         for (i = 0; i < MAXQUOTAS; i++)
4533                 if (old_opts.s_qf_names[i] &&
4534                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4535                         kfree(old_opts.s_qf_names[i]);
4536 #endif
4537         unlock_super(sb);
4538         if (enable_quota)
4539                 dquot_resume(sb, -1);
4540
4541         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4542         kfree(orig_data);
4543         return 0;
4544
4545 restore_opts:
4546         sb->s_flags = old_sb_flags;
4547         sbi->s_mount_opt = old_opts.s_mount_opt;
4548         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4549         sbi->s_resuid = old_opts.s_resuid;
4550         sbi->s_resgid = old_opts.s_resgid;
4551         sbi->s_commit_interval = old_opts.s_commit_interval;
4552         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4553         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4554 #ifdef CONFIG_QUOTA
4555         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4556         for (i = 0; i < MAXQUOTAS; i++) {
4557                 if (sbi->s_qf_names[i] &&
4558                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4559                         kfree(sbi->s_qf_names[i]);
4560                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4561         }
4562 #endif
4563         unlock_super(sb);
4564         kfree(orig_data);
4565         return err;
4566 }
4567
4568 /*
4569  * Note: calculating the overhead so we can be compatible with
4570  * historical BSD practice is quite difficult in the face of
4571  * clusters/bigalloc.  This is because multiple metadata blocks from
4572  * different block group can end up in the same allocation cluster.
4573  * Calculating the exact overhead in the face of clustered allocation
4574  * requires either O(all block bitmaps) in memory or O(number of block
4575  * groups**2) in time.  We will still calculate the superblock for
4576  * older file systems --- and if we come across with a bigalloc file
4577  * system with zero in s_overhead_clusters the estimate will be close to
4578  * correct especially for very large cluster sizes --- but for newer
4579  * file systems, it's better to calculate this figure once at mkfs
4580  * time, and store it in the superblock.  If the superblock value is
4581  * present (even for non-bigalloc file systems), we will use it.
4582  */
4583 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4584 {
4585         struct super_block *sb = dentry->d_sb;
4586         struct ext4_sb_info *sbi = EXT4_SB(sb);
4587         struct ext4_super_block *es = sbi->s_es;
4588         struct ext4_group_desc *gdp;
4589         u64 fsid;
4590         s64 bfree;
4591
4592         if (test_opt(sb, MINIX_DF)) {
4593                 sbi->s_overhead_last = 0;
4594         } else if (es->s_overhead_clusters) {
4595                 sbi->s_overhead_last = le32_to_cpu(es->s_overhead_clusters);
4596         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
4597                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4598                 ext4_fsblk_t overhead = 0;
4599
4600                 /*
4601                  * Compute the overhead (FS structures).  This is constant
4602                  * for a given filesystem unless the number of block groups
4603                  * changes so we cache the previous value until it does.
4604                  */
4605
4606                 /*
4607                  * All of the blocks before first_data_block are
4608                  * overhead
4609                  */
4610                 overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4611
4612                 /*
4613                  * Add the overhead found in each block group
4614                  */
4615                 for (i = 0; i < ngroups; i++) {
4616                         gdp = ext4_get_group_desc(sb, i, NULL);
4617                         overhead += ext4_num_overhead_clusters(sb, i, gdp);
4618                         cond_resched();
4619                 }
4620                 sbi->s_overhead_last = overhead;
4621                 smp_wmb();
4622                 sbi->s_blocks_last = ext4_blocks_count(es);
4623         }
4624
4625         buf->f_type = EXT4_SUPER_MAGIC;
4626         buf->f_bsize = sb->s_blocksize;
4627         buf->f_blocks = (ext4_blocks_count(es) -
4628                          EXT4_C2B(sbi, sbi->s_overhead_last));
4629         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
4630                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
4631         /* prevent underflow in case that few free space is available */
4632         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
4633         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
4634         if (buf->f_bfree < ext4_r_blocks_count(es))
4635                 buf->f_bavail = 0;
4636         buf->f_files = le32_to_cpu(es->s_inodes_count);
4637         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4638         buf->f_namelen = EXT4_NAME_LEN;
4639         fsid = le64_to_cpup((void *)es->s_uuid) ^
4640                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4641         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4642         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4643
4644         return 0;
4645 }
4646
4647 /* Helper function for writing quotas on sync - we need to start transaction
4648  * before quota file is locked for write. Otherwise the are possible deadlocks:
4649  * Process 1                         Process 2
4650  * ext4_create()                     quota_sync()
4651  *   jbd2_journal_start()                  write_dquot()
4652  *   dquot_initialize()                         down(dqio_mutex)
4653  *     down(dqio_mutex)                    jbd2_journal_start()
4654  *
4655  */
4656
4657 #ifdef CONFIG_QUOTA
4658
4659 static inline struct inode *dquot_to_inode(struct dquot *dquot)
4660 {
4661         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
4662 }
4663
4664 static int ext4_write_dquot(struct dquot *dquot)
4665 {
4666         int ret, err;
4667         handle_t *handle;
4668         struct inode *inode;
4669
4670         inode = dquot_to_inode(dquot);
4671         handle = ext4_journal_start(inode,
4672                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4673         if (IS_ERR(handle))
4674                 return PTR_ERR(handle);
4675         ret = dquot_commit(dquot);
4676         err = ext4_journal_stop(handle);
4677         if (!ret)
4678                 ret = err;
4679         return ret;
4680 }
4681
4682 static int ext4_acquire_dquot(struct dquot *dquot)
4683 {
4684         int ret, err;
4685         handle_t *handle;
4686
4687         handle = ext4_journal_start(dquot_to_inode(dquot),
4688                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4689         if (IS_ERR(handle))
4690                 return PTR_ERR(handle);
4691         ret = dquot_acquire(dquot);
4692         err = ext4_journal_stop(handle);
4693         if (!ret)
4694                 ret = err;
4695         return ret;
4696 }
4697
4698 static int ext4_release_dquot(struct dquot *dquot)
4699 {
4700         int ret, err;
4701         handle_t *handle;
4702
4703         handle = ext4_journal_start(dquot_to_inode(dquot),
4704                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4705         if (IS_ERR(handle)) {
4706                 /* Release dquot anyway to avoid endless cycle in dqput() */
4707                 dquot_release(dquot);
4708                 return PTR_ERR(handle);
4709         }
4710         ret = dquot_release(dquot);
4711         err = ext4_journal_stop(handle);
4712         if (!ret)
4713                 ret = err;
4714         return ret;
4715 }
4716
4717 static int ext4_mark_dquot_dirty(struct dquot *dquot)
4718 {
4719         /* Are we journaling quotas? */
4720         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
4721             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
4722                 dquot_mark_dquot_dirty(dquot);
4723                 return ext4_write_dquot(dquot);
4724         } else {
4725                 return dquot_mark_dquot_dirty(dquot);
4726         }
4727 }
4728
4729 static int ext4_write_info(struct super_block *sb, int type)
4730 {
4731         int ret, err;
4732         handle_t *handle;
4733
4734         /* Data block + inode block */
4735         handle = ext4_journal_start(sb->s_root->d_inode, 2);
4736         if (IS_ERR(handle))
4737                 return PTR_ERR(handle);
4738         ret = dquot_commit_info(sb, type);
4739         err = ext4_journal_stop(handle);
4740         if (!ret)
4741                 ret = err;
4742         return ret;
4743 }
4744
4745 /*
4746  * Turn on quotas during mount time - we need to find
4747  * the quota file and such...
4748  */
4749 static int ext4_quota_on_mount(struct super_block *sb, int type)
4750 {
4751         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4752                                         EXT4_SB(sb)->s_jquota_fmt, type);
4753 }
4754
4755 /*
4756  * Standard function to be called on quota_on
4757  */
4758 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4759                          struct path *path)
4760 {
4761         int err;
4762
4763         if (!test_opt(sb, QUOTA))
4764                 return -EINVAL;
4765
4766         /* Quotafile not on the same filesystem? */
4767         if (path->dentry->d_sb != sb)
4768                 return -EXDEV;
4769         /* Journaling quota? */
4770         if (EXT4_SB(sb)->s_qf_names[type]) {
4771                 /* Quotafile not in fs root? */
4772                 if (path->dentry->d_parent != sb->s_root)
4773                         ext4_msg(sb, KERN_WARNING,
4774                                 "Quota file not on filesystem root. "
4775                                 "Journaled quota will not work");
4776         }
4777
4778         /*
4779          * When we journal data on quota file, we have to flush journal to see
4780          * all updates to the file when we bypass pagecache...
4781          */
4782         if (EXT4_SB(sb)->s_journal &&
4783             ext4_should_journal_data(path->dentry->d_inode)) {
4784                 /*
4785                  * We don't need to lock updates but journal_flush() could
4786                  * otherwise be livelocked...
4787                  */
4788                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4789                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4790                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4791                 if (err)
4792                         return err;
4793         }
4794
4795         return dquot_quota_on(sb, type, format_id, path);
4796 }
4797
4798 static int ext4_quota_off(struct super_block *sb, int type)
4799 {
4800         struct inode *inode = sb_dqopt(sb)->files[type];
4801         handle_t *handle;
4802
4803         /* Force all delayed allocation blocks to be allocated.
4804          * Caller already holds s_umount sem */
4805         if (test_opt(sb, DELALLOC))
4806                 sync_filesystem(sb);
4807
4808         if (!inode)
4809                 goto out;
4810
4811         /* Update modification times of quota files when userspace can
4812          * start looking at them */
4813         handle = ext4_journal_start(inode, 1);
4814         if (IS_ERR(handle))
4815                 goto out;
4816         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
4817         ext4_mark_inode_dirty(handle, inode);
4818         ext4_journal_stop(handle);
4819
4820 out:
4821         return dquot_quota_off(sb, type);
4822 }
4823
4824 /* Read data from quotafile - avoid pagecache and such because we cannot afford
4825  * acquiring the locks... As quota files are never truncated and quota code
4826  * itself serializes the operations (and no one else should touch the files)
4827  * we don't have to be afraid of races */
4828 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
4829                                size_t len, loff_t off)
4830 {
4831         struct inode *inode = sb_dqopt(sb)->files[type];
4832         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4833         int err = 0;
4834         int offset = off & (sb->s_blocksize - 1);
4835         int tocopy;
4836         size_t toread;
4837         struct buffer_head *bh;
4838         loff_t i_size = i_size_read(inode);
4839
4840         if (off > i_size)
4841                 return 0;
4842         if (off+len > i_size)
4843                 len = i_size-off;
4844         toread = len;
4845         while (toread > 0) {
4846                 tocopy = sb->s_blocksize - offset < toread ?
4847                                 sb->s_blocksize - offset : toread;
4848                 bh = ext4_bread(NULL, inode, blk, 0, &err);
4849                 if (err)
4850                         return err;
4851                 if (!bh)        /* A hole? */
4852                         memset(data, 0, tocopy);
4853                 else
4854                         memcpy(data, bh->b_data+offset, tocopy);
4855                 brelse(bh);
4856                 offset = 0;
4857                 toread -= tocopy;
4858                 data += tocopy;
4859                 blk++;
4860         }
4861         return len;
4862 }
4863
4864 /* Write to quotafile (we know the transaction is already started and has
4865  * enough credits) */
4866 static ssize_t ext4_quota_write(struct super_block *sb, int type,
4867                                 const char *data, size_t len, loff_t off)
4868 {
4869         struct inode *inode = sb_dqopt(sb)->files[type];
4870         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4871         int err = 0;
4872         int offset = off & (sb->s_blocksize - 1);
4873         struct buffer_head *bh;
4874         handle_t *handle = journal_current_handle();
4875
4876         if (EXT4_SB(sb)->s_journal && !handle) {
4877                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4878                         " cancelled because transaction is not started",
4879                         (unsigned long long)off, (unsigned long long)len);
4880                 return -EIO;
4881         }
4882         /*
4883          * Since we account only one data block in transaction credits,
4884          * then it is impossible to cross a block boundary.
4885          */
4886         if (sb->s_blocksize - offset < len) {
4887                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4888                         " cancelled because not block aligned",
4889                         (unsigned long long)off, (unsigned long long)len);
4890                 return -EIO;
4891         }
4892
4893         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
4894         bh = ext4_bread(handle, inode, blk, 1, &err);
4895         if (!bh)
4896                 goto out;
4897         err = ext4_journal_get_write_access(handle, bh);
4898         if (err) {
4899                 brelse(bh);
4900                 goto out;
4901         }
4902         lock_buffer(bh);
4903         memcpy(bh->b_data+offset, data, len);
4904         flush_dcache_page(bh->b_page);
4905         unlock_buffer(bh);
4906         err = ext4_handle_dirty_metadata(handle, NULL, bh);
4907         brelse(bh);
4908 out:
4909         if (err) {
4910                 mutex_unlock(&inode->i_mutex);
4911                 return err;
4912         }
4913         if (inode->i_size < off + len) {
4914                 i_size_write(inode, off + len);
4915                 EXT4_I(inode)->i_disksize = inode->i_size;
4916                 ext4_mark_inode_dirty(handle, inode);
4917         }
4918         mutex_unlock(&inode->i_mutex);
4919         return len;
4920 }
4921
4922 #endif
4923
4924 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
4925                        const char *dev_name, void *data)
4926 {
4927         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
4928 }
4929
4930 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4931 static inline void register_as_ext2(void)
4932 {
4933         int err = register_filesystem(&ext2_fs_type);
4934         if (err)
4935                 printk(KERN_WARNING
4936                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
4937 }
4938
4939 static inline void unregister_as_ext2(void)
4940 {
4941         unregister_filesystem(&ext2_fs_type);
4942 }
4943
4944 static inline int ext2_feature_set_ok(struct super_block *sb)
4945 {
4946         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
4947                 return 0;
4948         if (sb->s_flags & MS_RDONLY)
4949                 return 1;
4950         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
4951                 return 0;
4952         return 1;
4953 }
4954 MODULE_ALIAS("ext2");
4955 #else
4956 static inline void register_as_ext2(void) { }
4957 static inline void unregister_as_ext2(void) { }
4958 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
4959 #endif
4960
4961 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4962 static inline void register_as_ext3(void)
4963 {
4964         int err = register_filesystem(&ext3_fs_type);
4965         if (err)
4966                 printk(KERN_WARNING
4967                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
4968 }
4969
4970 static inline void unregister_as_ext3(void)
4971 {
4972         unregister_filesystem(&ext3_fs_type);
4973 }
4974
4975 static inline int ext3_feature_set_ok(struct super_block *sb)
4976 {
4977         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
4978                 return 0;
4979         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
4980                 return 0;
4981         if (sb->s_flags & MS_RDONLY)
4982                 return 1;
4983         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
4984                 return 0;
4985         return 1;
4986 }
4987 MODULE_ALIAS("ext3");
4988 #else
4989 static inline void register_as_ext3(void) { }
4990 static inline void unregister_as_ext3(void) { }
4991 static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
4992 #endif
4993
4994 static struct file_system_type ext4_fs_type = {
4995         .owner          = THIS_MODULE,
4996         .name           = "ext4",
4997         .mount          = ext4_mount,
4998         .kill_sb        = kill_block_super,
4999         .fs_flags       = FS_REQUIRES_DEV,
5000 };
5001
5002 static int __init ext4_init_feat_adverts(void)
5003 {
5004         struct ext4_features *ef;
5005         int ret = -ENOMEM;
5006
5007         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
5008         if (!ef)
5009                 goto out;
5010
5011         ef->f_kobj.kset = ext4_kset;
5012         init_completion(&ef->f_kobj_unregister);
5013         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
5014                                    "features");
5015         if (ret) {
5016                 kfree(ef);
5017                 goto out;
5018         }
5019
5020         ext4_feat = ef;
5021         ret = 0;
5022 out:
5023         return ret;
5024 }
5025
5026 static void ext4_exit_feat_adverts(void)
5027 {
5028         kobject_put(&ext4_feat->f_kobj);
5029         wait_for_completion(&ext4_feat->f_kobj_unregister);
5030         kfree(ext4_feat);
5031 }
5032
5033 /* Shared across all ext4 file systems */
5034 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5035 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5036
5037 static int __init ext4_init_fs(void)
5038 {
5039         int i, err;
5040
5041         ext4_li_info = NULL;
5042         mutex_init(&ext4_li_mtx);
5043
5044         ext4_check_flag_values();
5045
5046         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5047                 mutex_init(&ext4__aio_mutex[i]);
5048                 init_waitqueue_head(&ext4__ioend_wq[i]);
5049         }
5050
5051         err = ext4_init_pageio();
5052         if (err)
5053                 return err;
5054         err = ext4_init_system_zone();
5055         if (err)
5056                 goto out6;
5057         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
5058         if (!ext4_kset)
5059                 goto out5;
5060         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
5061
5062         err = ext4_init_feat_adverts();
5063         if (err)
5064                 goto out4;
5065
5066         err = ext4_init_mballoc();
5067         if (err)
5068                 goto out3;
5069
5070         err = ext4_init_xattr();
5071         if (err)
5072                 goto out2;
5073         err = init_inodecache();
5074         if (err)
5075                 goto out1;
5076         register_as_ext3();
5077         register_as_ext2();
5078         err = register_filesystem(&ext4_fs_type);
5079         if (err)
5080                 goto out;
5081
5082         return 0;
5083 out:
5084         unregister_as_ext2();
5085         unregister_as_ext3();
5086         destroy_inodecache();
5087 out1:
5088         ext4_exit_xattr();
5089 out2:
5090         ext4_exit_mballoc();
5091 out3:
5092         ext4_exit_feat_adverts();
5093 out4:
5094         if (ext4_proc_root)
5095                 remove_proc_entry("fs/ext4", NULL);
5096         kset_unregister(ext4_kset);
5097 out5:
5098         ext4_exit_system_zone();
5099 out6:
5100         ext4_exit_pageio();
5101         return err;
5102 }
5103
5104 static void __exit ext4_exit_fs(void)
5105 {
5106         ext4_destroy_lazyinit_thread();
5107         unregister_as_ext2();
5108         unregister_as_ext3();
5109         unregister_filesystem(&ext4_fs_type);
5110         destroy_inodecache();
5111         ext4_exit_xattr();
5112         ext4_exit_mballoc();
5113         ext4_exit_feat_adverts();
5114         remove_proc_entry("fs/ext4", NULL);
5115         kset_unregister(ext4_kset);
5116         ext4_exit_system_zone();
5117         ext4_exit_pageio();
5118 }
5119
5120 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5121 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5122 MODULE_LICENSE("GPL");
5123 module_init(ext4_init_fs)
5124 module_exit(ext4_exit_fs)