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 #include "richacl.h"
  54
  55 #define CREATE_TRACE_POINTS
  56 #include <trace/events/ext4.h>
  57
  58 static struct proc_dir_entry *ext4_proc_root;
  59 static struct kset *ext4_kset;
  60 static struct ext4_lazy_init *ext4_li_info;
  61 static struct mutex ext4_li_mtx;
  62 static struct ext4_features *ext4_feat;
  63
  64 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  65                              unsigned long journal_devnum);
  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 void *ext4_kvmalloc(size_t size, gfp_t flags)
 116 {
 117         void *ret;
 118
 119         ret = kmalloc(size, flags);
 120         if (!ret)
 121                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 122         return ret;
 123 }
 124
 125 void *ext4_kvzalloc(size_t size, gfp_t flags)
 126 {
 127         void *ret;
 128
 129         ret = kzalloc(size, flags);
 130         if (!ret)
 131                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 132         return ret;
 133 }
 134
 135 void ext4_kvfree(void *ptr)
 136 {
 137         if (is_vmalloc_addr(ptr))
 138                 vfree(ptr);
 139         else
 140                 kfree(ptr);
 141
 142 }
 143
 144 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 145                                struct ext4_group_desc *bg)
 146 {
 147         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 148                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 149                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 150 }
 151
 152 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 153                                struct ext4_group_desc *bg)
 154 {
 155         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 156                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 157                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 158 }
 159
 160 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 161                               struct ext4_group_desc *bg)
 162 {
 163         return le32_to_cpu(bg->bg_inode_table_lo) |
 164                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 165                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 166 }
 167
 168 __u32 ext4_free_group_clusters(struct super_block *sb,
 169                                struct ext4_group_desc *bg)
 170 {
 171         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 172                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 173                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 174 }
 175
 176 __u32 ext4_free_inodes_count(struct super_block *sb,
 177                               struct ext4_group_desc *bg)
 178 {
 179         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 180                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 181                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 182 }
 183
 184 __u32 ext4_used_dirs_count(struct super_block *sb,
 185                               struct ext4_group_desc *bg)
 186 {
 187         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 188                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 189                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 190 }
 191
 192 __u32 ext4_itable_unused_count(struct super_block *sb,
 193                               struct ext4_group_desc *bg)
 194 {
 195         return le16_to_cpu(bg->bg_itable_unused_lo) |
 196                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 197                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 198 }
 199
 200 void ext4_block_bitmap_set(struct super_block *sb,
 201                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 202 {
 203         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 204         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 205                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 206 }
 207
 208 void ext4_inode_bitmap_set(struct super_block *sb,
 209                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 210 {
 211         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 212         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 213                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 214 }
 215
 216 void ext4_inode_table_set(struct super_block *sb,
 217                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 218 {
 219         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 220         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 221                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 222 }
 223
 224 void ext4_free_group_clusters_set(struct super_block *sb,
 225                                   struct ext4_group_desc *bg, __u32 count)
 226 {
 227         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 228         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 229                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 230 }
 231
 232 void ext4_free_inodes_set(struct super_block *sb,
 233                           struct ext4_group_desc *bg, __u32 count)
 234 {
 235         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 236         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 237                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 238 }
 239
 240 void ext4_used_dirs_set(struct super_block *sb,
 241                           struct ext4_group_desc *bg, __u32 count)
 242 {
 243         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 244         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 245                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 246 }
 247
 248 void ext4_itable_unused_set(struct super_block *sb,
 249                           struct ext4_group_desc *bg, __u32 count)
 250 {
 251         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 252         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 253                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 254 }
 255
 256
 257 /* Just increment the non-pointer handle value */
 258 static handle_t *ext4_get_nojournal(void)
 259 {
 260         handle_t *handle = current->journal_info;
 261         unsigned long ref_cnt = (unsigned long)handle;
 262
 263         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
 264
 265         ref_cnt++;
 266         handle = (handle_t *)ref_cnt;
 267
 268         current->journal_info = handle;
 269         return handle;
 270 }
 271
 272
 273 /* Decrement the non-pointer handle value */
 274 static void ext4_put_nojournal(handle_t *handle)
 275 {
 276         unsigned long ref_cnt = (unsigned long)handle;
 277
 278         BUG_ON(ref_cnt == 0);
 279
 280         ref_cnt--;
 281         handle = (handle_t *)ref_cnt;
 282
 283         current->journal_info = handle;
 284 }
 285
 286 /*
 287  * Wrappers for jbd2_journal_start/end.
 288  *
 289  * The only special thing we need to do here is to make sure that all
 290  * journal_end calls result in the superblock being marked dirty, so
 291  * that sync() will call the filesystem's write_super callback if
 292  * appropriate.
 293  *
 294  * To avoid j_barrier hold in userspace when a user calls freeze(),
 295  * ext4 prevents a new handle from being started by s_frozen, which
 296  * is in an upper layer.
 297  */
 298 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 299 {
 300         journal_t *journal;
 301         handle_t  *handle;
 302
 303         trace_ext4_journal_start(sb, nblocks, _RET_IP_);
 304         if (sb->s_flags & MS_RDONLY)
 305                 return ERR_PTR(-EROFS);
 306
 307         journal = EXT4_SB(sb)->s_journal;
 308         handle = ext4_journal_current_handle();
 309
 310         /*
 311          * If a handle has been started, it should be allowed to
 312          * finish, otherwise deadlock could happen between freeze
 313          * and others(e.g. truncate) due to the restart of the
 314          * journal handle if the filesystem is forzen and active
 315          * handles are not stopped.
 316          */
 317         if (!handle)
 318                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
 319
 320         if (!journal)
 321                 return ext4_get_nojournal();
 322         /*
 323          * Special case here: if the journal has aborted behind our
 324          * backs (eg. EIO in the commit thread), then we still need to
 325          * take the FS itself readonly cleanly.
 326          */
 327         if (is_journal_aborted(journal)) {
 328                 ext4_abort(sb, "Detected aborted journal");
 329                 return ERR_PTR(-EROFS);
 330         }
 331         return jbd2_journal_start(journal, nblocks);
 332 }
 333
 334 /*
 335  * The only special thing we need to do here is to make sure that all
 336  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 337  * that sync() will call the filesystem's write_super callback if
 338  * appropriate.
 339  */
 340 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
 341 {
 342         struct super_block *sb;
 343         int err;
 344         int rc;
 345
 346         if (!ext4_handle_valid(handle)) {
 347                 ext4_put_nojournal(handle);
 348                 return 0;
 349         }
 350         sb = handle->h_transaction->t_journal->j_private;
 351         err = handle->h_err;
 352         rc = jbd2_journal_stop(handle);
 353
 354         if (!err)
 355                 err = rc;
 356         if (err)
 357                 __ext4_std_error(sb, where, line, err);
 358         return err;
 359 }
 360
 361 void ext4_journal_abort_handle(const char *caller, unsigned int line,
 362                                const char *err_fn, struct buffer_head *bh,
 363                                handle_t *handle, int err)
 364 {
 365         char nbuf[16];
 366         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 367
 368         BUG_ON(!ext4_handle_valid(handle));
 369
 370         if (bh)
 371                 BUFFER_TRACE(bh, "abort");
 372
 373         if (!handle->h_err)
 374                 handle->h_err = err;
 375
 376         if (is_handle_aborted(handle))
 377                 return;
 378
 379         printk(KERN_ERR "%s:%d: aborting transaction: %s in %s\n",
 380                caller, line, errstr, err_fn);
 381
 382         jbd2_journal_abort_handle(handle);
 383 }
 384
 385 static void __save_error_info(struct super_block *sb, const char *func,
 386                             unsigned int line)
 387 {
 388         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 389
 390         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 391         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 392         es->s_last_error_time = cpu_to_le32(get_seconds());
 393         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 394         es->s_last_error_line = cpu_to_le32(line);
 395         if (!es->s_first_error_time) {
 396                 es->s_first_error_time = es->s_last_error_time;
 397                 strncpy(es->s_first_error_func, func,
 398                         sizeof(es->s_first_error_func));
 399                 es->s_first_error_line = cpu_to_le32(line);
 400                 es->s_first_error_ino = es->s_last_error_ino;
 401                 es->s_first_error_block = es->s_last_error_block;
 402         }
 403         /*
 404          * Start the daily error reporting function if it hasn't been
 405          * started already
 406          */
 407         if (!es->s_error_count)
 408                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 409         es->s_error_count = cpu_to_le32(le32_to_cpu(es->s_error_count) + 1);
 410 }
 411
 412 static void save_error_info(struct super_block *sb, const char *func,
 413                             unsigned int line)
 414 {
 415         __save_error_info(sb, func, line);
 416         ext4_commit_super(sb, 1);
 417 }
 418
 419 /*
 420  * The del_gendisk() function uninitializes the disk-specific data
 421  * structures, including the bdi structure, without telling anyone
 422  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 423  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 424  * This is a kludge to prevent these oops until we can put in a proper
 425  * hook in del_gendisk() to inform the VFS and file system layers.
 426  */
 427 static int block_device_ejected(struct super_block *sb)
 428 {
 429         struct inode *bd_inode = sb->s_bdev->bd_inode;
 430         struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info;
 431
 432         return bdi->dev == NULL;
 433 }
 434
 435
 436 /* Deal with the reporting of failure conditions on a filesystem such as
 437  * inconsistencies detected or read IO failures.
 438  *
 439  * On ext2, we can store the error state of the filesystem in the
 440  * superblock.  That is not possible on ext4, because we may have other
 441  * write ordering constraints on the superblock which prevent us from
 442  * writing it out straight away; and given that the journal is about to
 443  * be aborted, we can't rely on the current, or future, transactions to
 444  * write out the superblock safely.
 445  *
 446  * We'll just use the jbd2_journal_abort() error code to record an error in
 447  * the journal instead.  On recovery, the journal will complain about
 448  * that error until we've noted it down and cleared it.
 449  */
 450
 451 static void ext4_handle_error(struct super_block *sb)
 452 {
 453         if (sb->s_flags & MS_RDONLY)
 454                 return;
 455
 456         if (!test_opt(sb, ERRORS_CONT)) {
 457                 journal_t *journal = EXT4_SB(sb)->s_journal;
 458
 459                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 460                 if (journal)
 461                         jbd2_journal_abort(journal, -EIO);
 462         }
 463         if (test_opt(sb, ERRORS_RO)) {
 464                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 465                 sb->s_flags |= MS_RDONLY;
 466         }
 467         if (test_opt(sb, ERRORS_PANIC))
 468                 panic("EXT4-fs (device %s): panic forced after error\n",
 469                         sb->s_id);
 470 }
 471
 472 void __ext4_error(struct super_block *sb, const char *function,
 473                   unsigned int line, const char *fmt, ...)
 474 {
 475         struct va_format vaf;
 476         va_list args;
 477
 478         va_start(args, fmt);
 479         vaf.fmt = fmt;
 480         vaf.va = &args;
 481         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 482                sb->s_id, function, line, current->comm, &vaf);
 483         va_end(args);
 484
 485         ext4_handle_error(sb);
 486 }
 487
 488 void ext4_error_inode(struct inode *inode, const char *function,
 489                       unsigned int line, ext4_fsblk_t block,
 490                       const char *fmt, ...)
 491 {
 492         va_list args;
 493         struct va_format vaf;
 494         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 495
 496         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 497         es->s_last_error_block = cpu_to_le64(block);
 498         save_error_info(inode->i_sb, function, line);
 499         va_start(args, fmt);
 500         vaf.fmt = fmt;
 501         vaf.va = &args;
 502         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: inode #%lu: ",
 503                inode->i_sb->s_id, function, line, inode->i_ino);
 504         if (block)
 505                 printk(KERN_CONT "block %llu: ", block);
 506         printk(KERN_CONT "comm %s: %pV\n", current->comm, &vaf);
 507         va_end(args);
 508
 509         ext4_handle_error(inode->i_sb);
 510 }
 511
 512 void ext4_error_file(struct file *file, const char *function,
 513                      unsigned int line, ext4_fsblk_t block,
 514                      const char *fmt, ...)
 515 {
 516         va_list args;
 517         struct va_format vaf;
 518         struct ext4_super_block *es;
 519         struct inode *inode = file->f_dentry->d_inode;
 520         char pathname[80], *path;
 521
 522         es = EXT4_SB(inode->i_sb)->s_es;
 523         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 524         save_error_info(inode->i_sb, function, line);
 525         path = d_path(&(file->f_path), pathname, sizeof(pathname));
 526         if (IS_ERR(path))
 527                 path = "(unknown)";
 528         printk(KERN_CRIT
 529                "EXT4-fs error (device %s): %s:%d: inode #%lu: ",
 530                inode->i_sb->s_id, function, line, inode->i_ino);
 531         if (block)
 532                 printk(KERN_CONT "block %llu: ", block);
 533         va_start(args, fmt);
 534         vaf.fmt = fmt;
 535         vaf.va = &args;
 536         printk(KERN_CONT "comm %s: path %s: %pV\n", current->comm, path, &vaf);
 537         va_end(args);
 538
 539         ext4_handle_error(inode->i_sb);
 540 }
 541
 542 static const char *ext4_decode_error(struct super_block *sb, int errno,
 543                                      char nbuf[16])
 544 {
 545         char *errstr = NULL;
 546
 547         switch (errno) {
 548         case -EIO:
 549                 errstr = "IO failure";
 550                 break;
 551         case -ENOMEM:
 552                 errstr = "Out of memory";
 553                 break;
 554         case -EROFS:
 555                 if (!sb || (EXT4_SB(sb)->s_journal &&
 556                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 557                         errstr = "Journal has aborted";
 558                 else
 559                         errstr = "Readonly filesystem";
 560                 break;
 561         default:
 562                 /* If the caller passed in an extra buffer for unknown
 563                  * errors, textualise them now.  Else we just return
 564                  * NULL. */
 565                 if (nbuf) {
 566                         /* Check for truncated error codes... */
 567                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 568                                 errstr = nbuf;
 569                 }
 570                 break;
 571         }
 572
 573         return errstr;
 574 }
 575
 576 /* __ext4_std_error decodes expected errors from journaling functions
 577  * automatically and invokes the appropriate error response.  */
 578
 579 void __ext4_std_error(struct super_block *sb, const char *function,
 580                       unsigned int line, int errno)
 581 {
 582         char nbuf[16];
 583         const char *errstr;
 584
 585         /* Special case: if the error is EROFS, and we're not already
 586          * inside a transaction, then there's really no point in logging
 587          * an error. */
 588         if (errno == -EROFS && journal_current_handle() == NULL &&
 589             (sb->s_flags & MS_RDONLY))
 590                 return;
 591
 592         errstr = ext4_decode_error(sb, errno, nbuf);
 593         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 594                sb->s_id, function, line, errstr);
 595         save_error_info(sb, function, line);
 596
 597         ext4_handle_error(sb);
 598 }
 599
 600 /*
 601  * ext4_abort is a much stronger failure handler than ext4_error.  The
 602  * abort function may be used to deal with unrecoverable failures such
 603  * as journal IO errors or ENOMEM at a critical moment in log management.
 604  *
 605  * We unconditionally force the filesystem into an ABORT|READONLY state,
 606  * unless the error response on the fs has been set to panic in which
 607  * case we take the easy way out and panic immediately.
 608  */
 609
 610 void __ext4_abort(struct super_block *sb, const char *function,
 611                 unsigned int line, const char *fmt, ...)
 612 {
 613         va_list args;
 614
 615         save_error_info(sb, function, line);
 616         va_start(args, fmt);
 617         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 618                function, line);
 619         vprintk(fmt, args);
 620         printk("\n");
 621         va_end(args);
 622
 623         if ((sb->s_flags & MS_RDONLY) == 0) {
 624                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 625                 sb->s_flags |= MS_RDONLY;
 626                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 627                 if (EXT4_SB(sb)->s_journal)
 628                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 629                 save_error_info(sb, function, line);
 630         }
 631         if (test_opt(sb, ERRORS_PANIC))
 632                 panic("EXT4-fs panic from previous error\n");
 633 }
 634
 635 void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
 636 {
 637         struct va_format vaf;
 638         va_list args;
 639
 640         va_start(args, fmt);
 641         vaf.fmt = fmt;
 642         vaf.va = &args;
 643         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 644         va_end(args);
 645 }
 646
 647 void __ext4_warning(struct super_block *sb, const char *function,
 648                     unsigned int line, const char *fmt, ...)
 649 {
 650         struct va_format vaf;
 651         va_list args;
 652
 653         va_start(args, fmt);
 654         vaf.fmt = fmt;
 655         vaf.va = &args;
 656         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 657                sb->s_id, function, line, &vaf);
 658         va_end(args);
 659 }
 660
 661 void __ext4_grp_locked_error(const char *function, unsigned int line,
 662                              struct super_block *sb, ext4_group_t grp,
 663                              unsigned long ino, ext4_fsblk_t block,
 664                              const char *fmt, ...)
 665 __releases(bitlock)
 666 __acquires(bitlock)
 667 {
 668         struct va_format vaf;
 669         va_list args;
 670         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 671
 672         es->s_last_error_ino = cpu_to_le32(ino);
 673         es->s_last_error_block = cpu_to_le64(block);
 674         __save_error_info(sb, function, line);
 675
 676         va_start(args, fmt);
 677
 678         vaf.fmt = fmt;
 679         vaf.va = &args;
 680         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 681                sb->s_id, function, line, grp);
 682         if (ino)
 683                 printk(KERN_CONT "inode %lu: ", ino);
 684         if (block)
 685                 printk(KERN_CONT "block %llu:", (unsigned long long) block);
 686         printk(KERN_CONT "%pV\n", &vaf);
 687         va_end(args);
 688
 689         if (test_opt(sb, ERRORS_CONT)) {
 690                 ext4_commit_super(sb, 0);
 691                 return;
 692         }
 693
 694         ext4_unlock_group(sb, grp);
 695         ext4_handle_error(sb);
 696         /*
 697          * We only get here in the ERRORS_RO case; relocking the group
 698          * may be dangerous, but nothing bad will happen since the
 699          * filesystem will have already been marked read/only and the
 700          * journal has been aborted.  We return 1 as a hint to callers
 701          * who might what to use the return value from
 702          * ext4_grp_locked_error() to distinguish between the
 703          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 704          * aggressively from the ext4 function in question, with a
 705          * more appropriate error code.
 706          */
 707         ext4_lock_group(sb, grp);
 708         return;
 709 }
 710
 711 void ext4_update_dynamic_rev(struct super_block *sb)
 712 {
 713         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 714
 715         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 716                 return;
 717
 718         ext4_warning(sb,
 719                      "updating to rev %d because of new feature flag, "
 720                      "running e2fsck is recommended",
 721                      EXT4_DYNAMIC_REV);
 722
 723         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 724         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 725         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 726         /* leave es->s_feature_*compat flags alone */
 727         /* es->s_uuid will be set by e2fsck if empty */
 728
 729         /*
 730          * The rest of the superblock fields should be zero, and if not it
 731          * means they are likely already in use, so leave them alone.  We
 732          * can leave it up to e2fsck to clean up any inconsistencies there.
 733          */
 734 }
 735
 736 /*
 737  * Open the external journal device
 738  */
 739 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 740 {
 741         struct block_device *bdev;
 742         char b[BDEVNAME_SIZE];
 743
 744         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 745         if (IS_ERR(bdev))
 746                 goto fail;
 747         return bdev;
 748
 749 fail:
 750         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 751                         __bdevname(dev, b), PTR_ERR(bdev));
 752         return NULL;
 753 }
 754
 755 /*
 756  * Release the journal device
 757  */
 758 static int ext4_blkdev_put(struct block_device *bdev)
 759 {
 760         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 761 }
 762
 763 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 764 {
 765         struct block_device *bdev;
 766         int ret = -ENODEV;
 767
 768         bdev = sbi->journal_bdev;
 769         if (bdev) {
 770                 ret = ext4_blkdev_put(bdev);
 771                 sbi->journal_bdev = NULL;
 772         }
 773         return ret;
 774 }
 775
 776 static inline struct inode *orphan_list_entry(struct list_head *l)
 777 {
 778         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 779 }
 780
 781 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 782 {
 783         struct list_head *l;
 784
 785         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 786                  le32_to_cpu(sbi->s_es->s_last_orphan));
 787
 788         printk(KERN_ERR "sb_info orphan list:\n");
 789         list_for_each(l, &sbi->s_orphan) {
 790                 struct inode *inode = orphan_list_entry(l);
 791                 printk(KERN_ERR "  "
 792                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 793                        inode->i_sb->s_id, inode->i_ino, inode,
 794                        inode->i_mode, inode->i_nlink,
 795                        NEXT_ORPHAN(inode));
 796         }
 797 }
 798
 799 static void ext4_put_super(struct super_block *sb)
 800 {
 801         struct ext4_sb_info *sbi = EXT4_SB(sb);
 802         struct ext4_super_block *es = sbi->s_es;
 803         int i, err;
 804
 805         ext4_unregister_li_request(sb);
 806         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 807
 808         flush_workqueue(sbi->dio_unwritten_wq);
 809         destroy_workqueue(sbi->dio_unwritten_wq);
 810
 811         lock_super(sb);
 812         if (sb->s_dirt)
 813                 ext4_commit_super(sb, 1);
 814
 815         if (sbi->s_journal) {
 816                 err = jbd2_journal_destroy(sbi->s_journal);
 817                 sbi->s_journal = NULL;
 818                 if (err < 0)
 819                         ext4_abort(sb, "Couldn't clean up the journal");
 820         }
 821
 822         del_timer(&sbi->s_err_report);
 823         ext4_release_system_zone(sb);
 824         ext4_mb_release(sb);
 825         ext4_ext_release(sb);
 826         ext4_xattr_put_super(sb);
 827
 828         if (!(sb->s_flags & MS_RDONLY)) {
 829                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 830                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 831                 ext4_commit_super(sb, 1);
 832         }
 833         if (sbi->s_proc) {
 834                 remove_proc_entry(sb->s_id, ext4_proc_root);
 835         }
 836         kobject_del(&sbi->s_kobj);
 837
 838         for (i = 0; i < sbi->s_gdb_count; i++)
 839                 brelse(sbi->s_group_desc[i]);
 840         ext4_kvfree(sbi->s_group_desc);
 841         ext4_kvfree(sbi->s_flex_groups);
 842         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 843         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 844         percpu_counter_destroy(&sbi->s_dirs_counter);
 845         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 846         brelse(sbi->s_sbh);
 847 #ifdef CONFIG_QUOTA
 848         for (i = 0; i < MAXQUOTAS; i++)
 849                 kfree(sbi->s_qf_names[i]);
 850 #endif
 851
 852         /* Debugging code just in case the in-memory inode orphan list
 853          * isn't empty.  The on-disk one can be non-empty if we've
 854          * detected an error and taken the fs readonly, but the
 855          * in-memory list had better be clean by this point. */
 856         if (!list_empty(&sbi->s_orphan))
 857                 dump_orphan_list(sb, sbi);
 858         J_ASSERT(list_empty(&sbi->s_orphan));
 859
 860         invalidate_bdev(sb->s_bdev);
 861         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 862                 /*
 863                  * Invalidate the journal device's buffers.  We don't want them
 864                  * floating about in memory - the physical journal device may
 865                  * hotswapped, and it breaks the `ro-after' testing code.
 866                  */
 867                 sync_blockdev(sbi->journal_bdev);
 868                 invalidate_bdev(sbi->journal_bdev);
 869                 ext4_blkdev_remove(sbi);
 870         }
 871         if (sbi->s_mmp_tsk)
 872                 kthread_stop(sbi->s_mmp_tsk);
 873         sb->s_fs_info = NULL;
 874         /*
 875          * Now that we are completely done shutting down the
 876          * superblock, we need to actually destroy the kobject.
 877          */
 878         unlock_super(sb);
 879         kobject_put(&sbi->s_kobj);
 880         wait_for_completion(&sbi->s_kobj_unregister);
 881         kfree(sbi->s_blockgroup_lock);
 882         kfree(sbi);
 883 }
 884
 885 static struct kmem_cache *ext4_inode_cachep;
 886
 887 /*
 888  * Called inside transaction, so use GFP_NOFS
 889  */
 890 static struct inode *ext4_alloc_inode(struct super_block *sb)
 891 {
 892         struct ext4_inode_info *ei;
 893
 894         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 895         if (!ei)
 896                 return NULL;
 897 #ifdef CONFIG_EXT4_FS_RICHACL
 898         ei->i_richacl = EXT4_RICHACL_NOT_CACHED;
 899 #endif
 900         ei->vfs_inode.i_version = 1;
 901         ei->vfs_inode.i_data.writeback_index = 0;
 902         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 903         INIT_LIST_HEAD(&ei->i_prealloc_list);
 904         spin_lock_init(&ei->i_prealloc_lock);
 905         ei->i_reserved_data_blocks = 0;
 906         ei->i_reserved_meta_blocks = 0;
 907         ei->i_allocated_meta_blocks = 0;
 908         ei->i_da_metadata_calc_len = 0;
 909         spin_lock_init(&(ei->i_block_reservation_lock));
 910 #ifdef CONFIG_QUOTA
 911         ei->i_reserved_quota = 0;
 912 #endif
 913         ei->jinode = NULL;
 914         INIT_LIST_HEAD(&ei->i_completed_io_list);
 915         spin_lock_init(&ei->i_completed_io_lock);
 916         ei->cur_aio_dio = NULL;
 917         ei->i_sync_tid = 0;
 918         ei->i_datasync_tid = 0;
 919         atomic_set(&ei->i_ioend_count, 0);
 920         atomic_set(&ei->i_aiodio_unwritten, 0);
 921
 922         return &ei->vfs_inode;
 923 }
 924
 925 static int ext4_drop_inode(struct inode *inode)
 926 {
 927         int drop = generic_drop_inode(inode);
 928
 929         trace_ext4_drop_inode(inode, drop);
 930         return drop;
 931 }
 932
 933 static void ext4_i_callback(struct rcu_head *head)
 934 {
 935         struct inode *inode = container_of(head, struct inode, i_rcu);
 936         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 937 }
 938
 939 static void ext4_destroy_inode(struct inode *inode)
 940 {
 941         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 942                 ext4_msg(inode->i_sb, KERN_ERR,
 943                          "Inode %lu (%p): orphan list check failed!",
 944                          inode->i_ino, EXT4_I(inode));
 945                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 946                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 947                                 true);
 948                 dump_stack();
 949         }
 950         call_rcu(&inode->i_rcu, ext4_i_callback);
 951 }
 952
 953 static void init_once(void *foo)
 954 {
 955         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 956
 957         INIT_LIST_HEAD(&ei->i_orphan);
 958 #ifdef CONFIG_EXT4_FS_XATTR
 959         init_rwsem(&ei->xattr_sem);
 960 #endif
 961         init_rwsem(&ei->i_data_sem);
 962         inode_init_once(&ei->vfs_inode);
 963 }
 964
 965 static int init_inodecache(void)
 966 {
 967         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 968                                              sizeof(struct ext4_inode_info),
 969                                              0, (SLAB_RECLAIM_ACCOUNT|
 970                                                 SLAB_MEM_SPREAD),
 971                                              init_once);
 972         if (ext4_inode_cachep == NULL)
 973                 return -ENOMEM;
 974         return 0;
 975 }
 976
 977 static void destroy_inodecache(void)
 978 {
 979         kmem_cache_destroy(ext4_inode_cachep);
 980 }
 981
 982 void ext4_clear_inode(struct inode *inode)
 983 {
 984         invalidate_inode_buffers(inode);
 985         end_writeback(inode);
 986         dquot_drop(inode);
 987 #ifdef CONFIG_EXT4_FS_RICHACL
 988         if (EXT4_I(inode)->i_richacl &&
 989                 EXT4_I(inode)->i_richacl != EXT4_RICHACL_NOT_CACHED) {
 990                 richacl_put(EXT4_I(inode)->i_richacl);
 991                 EXT4_I(inode)->i_richacl = EXT4_RICHACL_NOT_CACHED;
 992         }
 993 #endif
 994         ext4_discard_preallocations(inode);
 995         if (EXT4_I(inode)->jinode) {
 996                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
 997                                                EXT4_I(inode)->jinode);
 998                 jbd2_free_inode(EXT4_I(inode)->jinode);
 999                 EXT4_I(inode)->jinode = NULL;
1000         }
1001 }
1002
1003 static inline void ext4_show_quota_options(struct seq_file *seq,
1004                                            struct super_block *sb)
1005 {
1006 #if defined(CONFIG_QUOTA)
1007         struct ext4_sb_info *sbi = EXT4_SB(sb);
1008
1009         if (sbi->s_jquota_fmt) {
1010                 char *fmtname = "";
1011
1012                 switch (sbi->s_jquota_fmt) {
1013                 case QFMT_VFS_OLD:
1014                         fmtname = "vfsold";
1015                         break;
1016                 case QFMT_VFS_V0:
1017                         fmtname = "vfsv0";
1018                         break;
1019                 case QFMT_VFS_V1:
1020                         fmtname = "vfsv1";
1021                         break;
1022                 }
1023                 seq_printf(seq, ",jqfmt=%s", fmtname);
1024         }
1025
1026         if (sbi->s_qf_names[USRQUOTA])
1027                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1028
1029         if (sbi->s_qf_names[GRPQUOTA])
1030                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1031
1032         if (test_opt(sb, USRQUOTA))
1033                 seq_puts(seq, ",usrquota");
1034
1035         if (test_opt(sb, GRPQUOTA))
1036                 seq_puts(seq, ",grpquota");
1037 #endif
1038 }
1039
1040 /*
1041  * Show an option if
1042  *  - it's set to a non-default value OR
1043  *  - if the per-sb default is different from the global default
1044  */
1045 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1046 {
1047         int def_errors;
1048         unsigned long def_mount_opts;
1049         struct super_block *sb = root->d_sb;
1050         struct ext4_sb_info *sbi = EXT4_SB(sb);
1051         struct ext4_super_block *es = sbi->s_es;
1052
1053         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
1054         def_errors     = le16_to_cpu(es->s_errors);
1055
1056         if (sbi->s_sb_block != 1)
1057                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
1058         if (test_opt(sb, MINIX_DF))
1059                 seq_puts(seq, ",minixdf");
1060         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
1061                 seq_puts(seq, ",grpid");
1062         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
1063                 seq_puts(seq, ",nogrpid");
1064         if (sbi->s_resuid != EXT4_DEF_RESUID ||
1065             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
1066                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
1067         }
1068         if (sbi->s_resgid != EXT4_DEF_RESGID ||
1069             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
1070                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
1071         }
1072         if (test_opt(sb, ERRORS_RO)) {
1073                 if (def_errors == EXT4_ERRORS_PANIC ||
1074                     def_errors == EXT4_ERRORS_CONTINUE) {
1075                         seq_puts(seq, ",errors=remount-ro");
1076                 }
1077         }
1078         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1079                 seq_puts(seq, ",errors=continue");
1080         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1081                 seq_puts(seq, ",errors=panic");
1082         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
1083                 seq_puts(seq, ",nouid32");
1084         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
1085                 seq_puts(seq, ",debug");
1086 #ifdef CONFIG_EXT4_FS_XATTR
1087         if (test_opt(sb, XATTR_USER))
1088                 seq_puts(seq, ",user_xattr");
1089         if (!test_opt(sb, XATTR_USER))
1090                 seq_puts(seq, ",nouser_xattr");
1091 #endif
1092 #if defined(CONFIG_EXT4_FS_POSIX_ACL) || defined(CONFIG_EXT4_FS_RICHACL)
1093         if (sb->s_flags & MS_POSIXACL) {
1094                 if (!(def_mount_opts & EXT4_DEFM_ACL))
1095                         seq_puts(seq, ",acl");
1096         } else if (sb->s_flags & MS_RICHACL)
1097                 seq_puts(seq, ",richacl");
1098         else if (def_mount_opts & EXT4_DEFM_ACL)
1099                 seq_puts(seq, ",noacl");
1100 #endif
1101         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
1102                 seq_printf(seq, ",commit=%u",
1103                            (unsigned) (sbi->s_commit_interval / HZ));
1104         }
1105         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
1106                 seq_printf(seq, ",min_batch_time=%u",
1107                            (unsigned) sbi->s_min_batch_time);
1108         }
1109         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
1110                 seq_printf(seq, ",max_batch_time=%u",
1111                            (unsigned) sbi->s_max_batch_time);
1112         }
1113
1114         /*
1115          * We're changing the default of barrier mount option, so
1116          * let's always display its mount state so it's clear what its
1117          * status is.
1118          */
1119         seq_puts(seq, ",barrier=");
1120         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
1121         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
1122                 seq_puts(seq, ",journal_async_commit");
1123         else if (test_opt(sb, JOURNAL_CHECKSUM))
1124                 seq_puts(seq, ",journal_checksum");
1125         if (test_opt(sb, I_VERSION))
1126                 seq_puts(seq, ",i_version");
1127         if (!test_opt(sb, DELALLOC) &&
1128             !(def_mount_opts & EXT4_DEFM_NODELALLOC))
1129                 seq_puts(seq, ",nodelalloc");
1130
1131         if (!test_opt(sb, MBLK_IO_SUBMIT))
1132                 seq_puts(seq, ",nomblk_io_submit");
1133         if (sbi->s_stripe)
1134                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
1135         /*
1136          * journal mode get enabled in different ways
1137          * So just print the value even if we didn't specify it
1138          */
1139         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1140                 seq_puts(seq, ",data=journal");
1141         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1142                 seq_puts(seq, ",data=ordered");
1143         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1144                 seq_puts(seq, ",data=writeback");
1145
1146         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1147                 seq_printf(seq, ",inode_readahead_blks=%u",
1148                            sbi->s_inode_readahead_blks);
1149
1150         if (test_opt(sb, DATA_ERR_ABORT))
1151                 seq_puts(seq, ",data_err=abort");
1152
1153         if (test_opt(sb, NO_AUTO_DA_ALLOC))
1154                 seq_puts(seq, ",noauto_da_alloc");
1155
1156         if (test_opt(sb, DISCARD) && !(def_mount_opts & EXT4_DEFM_DISCARD))
1157                 seq_puts(seq, ",discard");
1158
1159         if (test_opt(sb, NOLOAD))
1160                 seq_puts(seq, ",norecovery");
1161
1162         if (test_opt(sb, DIOREAD_NOLOCK))
1163                 seq_puts(seq, ",dioread_nolock");
1164
1165         if (test_opt(sb, BLOCK_VALIDITY) &&
1166             !(def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY))
1167                 seq_puts(seq, ",block_validity");
1168
1169         if (!test_opt(sb, INIT_INODE_TABLE))
1170                 seq_puts(seq, ",noinit_itable");
1171         else if (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)
1172                 seq_printf(seq, ",init_itable=%u",
1173                            (unsigned) sbi->s_li_wait_mult);
1174
1175         ext4_show_quota_options(seq, sb);
1176
1177         return 0;
1178 }
1179
1180 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1181                                         u64 ino, u32 generation)
1182 {
1183         struct inode *inode;
1184
1185         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1186                 return ERR_PTR(-ESTALE);
1187         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1188                 return ERR_PTR(-ESTALE);
1189
1190         /* iget isn't really right if the inode is currently unallocated!!
1191          *
1192          * ext4_read_inode will return a bad_inode if the inode had been
1193          * deleted, so we should be safe.
1194          *
1195          * Currently we don't know the generation for parent directory, so
1196          * a generation of 0 means "accept any"
1197          */
1198         inode = ext4_iget(sb, ino);
1199         if (IS_ERR(inode))
1200                 return ERR_CAST(inode);
1201         if (generation && inode->i_generation != generation) {
1202                 iput(inode);
1203                 return ERR_PTR(-ESTALE);
1204         }
1205
1206         return inode;
1207 }
1208
1209 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1210                                         int fh_len, int fh_type)
1211 {
1212         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1213                                     ext4_nfs_get_inode);
1214 }
1215
1216 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1217                                         int fh_len, int fh_type)
1218 {
1219         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1220                                     ext4_nfs_get_inode);
1221 }
1222
1223 /*
1224  * Try to release metadata pages (indirect blocks, directories) which are
1225  * mapped via the block device.  Since these pages could have journal heads
1226  * which would prevent try_to_free_buffers() from freeing them, we must use
1227  * jbd2 layer's try_to_free_buffers() function to release them.
1228  */
1229 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1230                                  gfp_t wait)
1231 {
1232         journal_t *journal = EXT4_SB(sb)->s_journal;
1233
1234         WARN_ON(PageChecked(page));
1235         if (!page_has_buffers(page))
1236                 return 0;
1237         if (journal)
1238                 return jbd2_journal_try_to_free_buffers(journal, page,
1239                                                         wait & ~__GFP_WAIT);
1240         return try_to_free_buffers(page);
1241 }
1242
1243 #ifdef CONFIG_QUOTA
1244 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1245 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1246
1247 static int ext4_write_dquot(struct dquot *dquot);
1248 static int ext4_acquire_dquot(struct dquot *dquot);
1249 static int ext4_release_dquot(struct dquot *dquot);
1250 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1251 static int ext4_write_info(struct super_block *sb, int type);
1252 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1253                          struct path *path);
1254 static int ext4_quota_off(struct super_block *sb, int type);
1255 static int ext4_quota_on_mount(struct super_block *sb, int type);
1256 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1257                                size_t len, loff_t off);
1258 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1259                                 const char *data, size_t len, loff_t off);
1260
1261 static const struct dquot_operations ext4_quota_operations = {
1262         .get_reserved_space = ext4_get_reserved_space,
1263         .write_dquot    = ext4_write_dquot,
1264         .acquire_dquot  = ext4_acquire_dquot,
1265         .release_dquot  = ext4_release_dquot,
1266         .mark_dirty     = ext4_mark_dquot_dirty,
1267         .write_info     = ext4_write_info,
1268         .alloc_dquot    = dquot_alloc,
1269         .destroy_dquot  = dquot_destroy,
1270 };
1271
1272 static const struct quotactl_ops ext4_qctl_operations = {
1273         .quota_on       = ext4_quota_on,
1274         .quota_off      = ext4_quota_off,
1275         .quota_sync     = dquot_quota_sync,
1276         .get_info       = dquot_get_dqinfo,
1277         .set_info       = dquot_set_dqinfo,
1278         .get_dqblk      = dquot_get_dqblk,
1279         .set_dqblk      = dquot_set_dqblk
1280 };
1281 #endif
1282
1283 static const struct super_operations ext4_sops = {
1284         .alloc_inode    = ext4_alloc_inode,
1285         .destroy_inode  = ext4_destroy_inode,
1286         .write_inode    = ext4_write_inode,
1287         .dirty_inode    = ext4_dirty_inode,
1288         .drop_inode     = ext4_drop_inode,
1289         .evict_inode    = ext4_evict_inode,
1290         .put_super      = ext4_put_super,
1291         .sync_fs        = ext4_sync_fs,
1292         .freeze_fs      = ext4_freeze,
1293         .unfreeze_fs    = ext4_unfreeze,
1294         .statfs         = ext4_statfs,
1295         .remount_fs     = ext4_remount,
1296         .show_options   = ext4_show_options,
1297 #ifdef CONFIG_QUOTA
1298         .quota_read     = ext4_quota_read,
1299         .quota_write    = ext4_quota_write,
1300 #endif
1301         .bdev_try_to_free_page = bdev_try_to_free_page,
1302 };
1303
1304 static const struct super_operations ext4_nojournal_sops = {
1305         .alloc_inode    = ext4_alloc_inode,
1306         .destroy_inode  = ext4_destroy_inode,
1307         .write_inode    = ext4_write_inode,
1308         .dirty_inode    = ext4_dirty_inode,
1309         .drop_inode     = ext4_drop_inode,
1310         .evict_inode    = ext4_evict_inode,
1311         .write_super    = ext4_write_super,
1312         .put_super      = ext4_put_super,
1313         .statfs         = ext4_statfs,
1314         .remount_fs     = ext4_remount,
1315         .show_options   = ext4_show_options,
1316 #ifdef CONFIG_QUOTA
1317         .quota_read     = ext4_quota_read,
1318         .quota_write    = ext4_quota_write,
1319 #endif
1320         .bdev_try_to_free_page = bdev_try_to_free_page,
1321 };
1322
1323 static const struct export_operations ext4_export_ops = {
1324         .fh_to_dentry = ext4_fh_to_dentry,
1325         .fh_to_parent = ext4_fh_to_parent,
1326         .get_parent = ext4_get_parent,
1327 };
1328
1329 enum {
1330         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1331         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1332         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1333         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_richacl, Opt_noacl,
1334         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1335         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1336         Opt_journal_update, Opt_journal_dev,
1337         Opt_journal_checksum, Opt_journal_async_commit,
1338         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1339         Opt_data_err_abort, Opt_data_err_ignore,
1340         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1341         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1342         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1343         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1344         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1345         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1346         Opt_inode_readahead_blks, Opt_journal_ioprio,
1347         Opt_dioread_nolock, Opt_dioread_lock,
1348         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1349 };
1350
1351 static const match_table_t tokens = {
1352         {Opt_bsd_df, "bsddf"},
1353         {Opt_minix_df, "minixdf"},
1354         {Opt_grpid, "grpid"},
1355         {Opt_grpid, "bsdgroups"},
1356         {Opt_nogrpid, "nogrpid"},
1357         {Opt_nogrpid, "sysvgroups"},
1358         {Opt_resgid, "resgid=%u"},
1359         {Opt_resuid, "resuid=%u"},
1360         {Opt_sb, "sb=%u"},
1361         {Opt_err_cont, "errors=continue"},
1362         {Opt_err_panic, "errors=panic"},
1363         {Opt_err_ro, "errors=remount-ro"},
1364         {Opt_nouid32, "nouid32"},
1365         {Opt_debug, "debug"},
1366         {Opt_oldalloc, "oldalloc"},
1367         {Opt_orlov, "orlov"},
1368         {Opt_user_xattr, "user_xattr"},
1369         {Opt_nouser_xattr, "nouser_xattr"},
1370         {Opt_acl, "acl"},
1371         {Opt_richacl, "richacl"},
1372         {Opt_noacl, "noacl"},
1373         {Opt_noload, "noload"},
1374         {Opt_noload, "norecovery"},
1375         {Opt_nobh, "nobh"},
1376         {Opt_bh, "bh"},
1377         {Opt_commit, "commit=%u"},
1378         {Opt_min_batch_time, "min_batch_time=%u"},
1379         {Opt_max_batch_time, "max_batch_time=%u"},
1380         {Opt_journal_update, "journal=update"},
1381         {Opt_journal_dev, "journal_dev=%u"},
1382         {Opt_journal_checksum, "journal_checksum"},
1383         {Opt_journal_async_commit, "journal_async_commit"},
1384         {Opt_abort, "abort"},
1385         {Opt_data_journal, "data=journal"},
1386         {Opt_data_ordered, "data=ordered"},
1387         {Opt_data_writeback, "data=writeback"},
1388         {Opt_data_err_abort, "data_err=abort"},
1389         {Opt_data_err_ignore, "data_err=ignore"},
1390         {Opt_offusrjquota, "usrjquota="},
1391         {Opt_usrjquota, "usrjquota=%s"},
1392         {Opt_offgrpjquota, "grpjquota="},
1393         {Opt_grpjquota, "grpjquota=%s"},
1394         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1395         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1396         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1397         {Opt_grpquota, "grpquota"},
1398         {Opt_noquota, "noquota"},
1399         {Opt_quota, "quota"},
1400         {Opt_usrquota, "usrquota"},
1401         {Opt_barrier, "barrier=%u"},
1402         {Opt_barrier, "barrier"},
1403         {Opt_nobarrier, "nobarrier"},
1404         {Opt_i_version, "i_version"},
1405         {Opt_stripe, "stripe=%u"},
1406         {Opt_resize, "resize"},
1407         {Opt_delalloc, "delalloc"},
1408         {Opt_nodelalloc, "nodelalloc"},
1409         {Opt_mblk_io_submit, "mblk_io_submit"},
1410         {Opt_nomblk_io_submit, "nomblk_io_submit"},
1411         {Opt_block_validity, "block_validity"},
1412         {Opt_noblock_validity, "noblock_validity"},
1413         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1414         {Opt_journal_ioprio, "journal_ioprio=%u"},
1415         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1416         {Opt_auto_da_alloc, "auto_da_alloc"},
1417         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1418         {Opt_dioread_nolock, "dioread_nolock"},
1419         {Opt_dioread_lock, "dioread_lock"},
1420         {Opt_discard, "discard"},
1421         {Opt_nodiscard, "nodiscard"},
1422         {Opt_init_itable, "init_itable=%u"},
1423         {Opt_init_itable, "init_itable"},
1424         {Opt_noinit_itable, "noinit_itable"},
1425         {Opt_err, NULL},
1426 };
1427
1428 static ext4_fsblk_t get_sb_block(void **data)
1429 {
1430         ext4_fsblk_t    sb_block;
1431         char            *options = (char *) *data;
1432
1433         if (!options || strncmp(options, "sb=", 3) != 0)
1434                 return 1;       /* Default location */
1435
1436         options += 3;
1437         /* TODO: use simple_strtoll with >32bit ext4 */
1438         sb_block = simple_strtoul(options, &options, 0);
1439         if (*options && *options != ',') {
1440                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1441                        (char *) *data);
1442                 return 1;
1443         }
1444         if (*options == ',')
1445                 options++;
1446         *data = (void *) options;
1447
1448         return sb_block;
1449 }
1450
1451 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1452 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1453         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1454
1455 #ifdef CONFIG_QUOTA
1456 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1457 {
1458         struct ext4_sb_info *sbi = EXT4_SB(sb);
1459         char *qname;
1460
1461         if (sb_any_quota_loaded(sb) &&
1462                 !sbi->s_qf_names[qtype]) {
1463                 ext4_msg(sb, KERN_ERR,
1464                         "Cannot change journaled "
1465                         "quota options when quota turned on");
1466                 return 0;
1467         }
1468         qname = match_strdup(args);
1469         if (!qname) {
1470                 ext4_msg(sb, KERN_ERR,
1471                         "Not enough memory for storing quotafile name");
1472                 return 0;
1473         }
1474         if (sbi->s_qf_names[qtype] &&
1475                 strcmp(sbi->s_qf_names[qtype], qname)) {
1476                 ext4_msg(sb, KERN_ERR,
1477                         "%s quota file already specified", QTYPE2NAME(qtype));
1478                 kfree(qname);
1479                 return 0;
1480         }
1481         sbi->s_qf_names[qtype] = qname;
1482         if (strchr(sbi->s_qf_names[qtype], '/')) {
1483                 ext4_msg(sb, KERN_ERR,
1484                         "quotafile must be on filesystem root");
1485                 kfree(sbi->s_qf_names[qtype]);
1486                 sbi->s_qf_names[qtype] = NULL;
1487                 return 0;
1488         }
1489         set_opt(sb, QUOTA);
1490         return 1;
1491 }
1492
1493 static int clear_qf_name(struct super_block *sb, int qtype)
1494 {
1495
1496         struct ext4_sb_info *sbi = EXT4_SB(sb);
1497
1498         if (sb_any_quota_loaded(sb) &&
1499                 sbi->s_qf_names[qtype]) {
1500                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1501                         " when quota turned on");
1502                 return 0;
1503         }
1504         /*
1505          * The space will be released later when all options are confirmed
1506          * to be correct
1507          */
1508         sbi->s_qf_names[qtype] = NULL;
1509         return 1;
1510 }
1511 #endif
1512
1513 static int parse_options(char *options, struct super_block *sb,
1514                          unsigned long *journal_devnum,
1515                          unsigned int *journal_ioprio,
1516                          ext4_fsblk_t *n_blocks_count, int is_remount)
1517 {
1518         struct ext4_sb_info *sbi = EXT4_SB(sb);
1519         char *p;
1520         substring_t args[MAX_OPT_ARGS];
1521         int data_opt = 0;
1522         int option;
1523 #ifdef CONFIG_QUOTA
1524         int qfmt;
1525 #endif
1526
1527         if (!options)
1528                 return 1;
1529
1530         while ((p = strsep(&options, ",")) != NULL) {
1531                 int token;
1532                 if (!*p)
1533                         continue;
1534
1535                 /*
1536                  * Initialize args struct so we know whether arg was
1537                  * found; some options take optional arguments.
1538                  */
1539                 args[0].to = args[0].from = NULL;
1540                 token = match_token(p, tokens, args);
1541                 switch (token) {
1542                 case Opt_bsd_df:
1543                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1544                         clear_opt(sb, MINIX_DF);
1545                         break;
1546                 case Opt_minix_df:
1547                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1548                         set_opt(sb, MINIX_DF);
1549
1550                         break;
1551                 case Opt_grpid:
1552                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1553                         set_opt(sb, GRPID);
1554
1555                         break;
1556                 case Opt_nogrpid:
1557                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1558                         clear_opt(sb, GRPID);
1559
1560                         break;
1561                 case Opt_resuid:
1562                         if (match_int(&args[0], &option))
1563                                 return 0;
1564                         sbi->s_resuid = option;
1565                         break;
1566                 case Opt_resgid:
1567                         if (match_int(&args[0], &option))
1568                                 return 0;
1569                         sbi->s_resgid = option;
1570                         break;
1571                 case Opt_sb:
1572                         /* handled by get_sb_block() instead of here */
1573                         /* *sb_block = match_int(&args[0]); */
1574                         break;
1575                 case Opt_err_panic:
1576                         clear_opt(sb, ERRORS_CONT);
1577                         clear_opt(sb, ERRORS_RO);
1578                         set_opt(sb, ERRORS_PANIC);
1579                         break;
1580                 case Opt_err_ro:
1581                         clear_opt(sb, ERRORS_CONT);
1582                         clear_opt(sb, ERRORS_PANIC);
1583                         set_opt(sb, ERRORS_RO);
1584                         break;
1585                 case Opt_err_cont:
1586                         clear_opt(sb, ERRORS_RO);
1587                         clear_opt(sb, ERRORS_PANIC);
1588                         set_opt(sb, ERRORS_CONT);
1589                         break;
1590                 case Opt_nouid32:
1591                         set_opt(sb, NO_UID32);
1592                         break;
1593                 case Opt_debug:
1594                         set_opt(sb, DEBUG);
1595                         break;
1596                 case Opt_oldalloc:
1597                         ext4_msg(sb, KERN_WARNING,
1598                                  "Ignoring deprecated oldalloc option");
1599                         break;
1600                 case Opt_orlov:
1601                         ext4_msg(sb, KERN_WARNING,
1602                                  "Ignoring deprecated orlov option");
1603                         break;
1604 #ifdef CONFIG_EXT4_FS_XATTR
1605                 case Opt_user_xattr:
1606                         set_opt(sb, XATTR_USER);
1607                         break;
1608                 case Opt_nouser_xattr:
1609                         clear_opt(sb, XATTR_USER);
1610                         break;
1611 #else
1612                 case Opt_user_xattr:
1613                 case Opt_nouser_xattr:
1614                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1615                         break;
1616 #endif
1617 #if defined(CONFIG_EXT4_FS_POSIX_ACL) || defined(CONFIG_EXT4_FS_RICHACL)
1618 # ifdef CONFIG_EXT4_FS_POSIX_ACL
1619                 case Opt_acl:
1620                         if (!(sb->s_flags & MS_RICHACL))
1621                                 sb->s_flags |= MS_POSIXACL;
1622                         break;
1623 # endif
1624 # ifdef CONFIG_EXT4_FS_RICHACL
1625                 case Opt_richacl:
1626                         sb->s_flags &= ~MS_POSIXACL;
1627                         sb->s_flags |= MS_RICHACL;
1628                         break;
1629 # endif
1630                 case Opt_noacl:
1631                         sb->s_flags &= ~(MS_POSIXACL | MS_RICHACL);
1632                         break;
1633 #else
1634                 case Opt_acl:
1635                 case Opt_noacl:
1636                         ext4_msg(sb, KERN_ERR, "(no)acl/richacl options not supported");
1637                         break;
1638 #endif
1639                 case Opt_journal_update:
1640                         /* @@@ FIXME */
1641                         /* Eventually we will want to be able to create
1642                            a journal file here.  For now, only allow the
1643                            user to specify an existing inode to be the
1644                            journal file. */
1645                         if (is_remount) {
1646                                 ext4_msg(sb, KERN_ERR,
1647                                          "Cannot specify journal on remount");
1648                                 return 0;
1649                         }
1650                         set_opt(sb, UPDATE_JOURNAL);
1651                         break;
1652                 case Opt_journal_dev:
1653                         if (is_remount) {
1654                                 ext4_msg(sb, KERN_ERR,
1655                                         "Cannot specify journal on remount");
1656                                 return 0;
1657                         }
1658                         if (match_int(&args[0], &option))
1659                                 return 0;
1660                         *journal_devnum = option;
1661                         break;
1662                 case Opt_journal_checksum:
1663                         set_opt(sb, JOURNAL_CHECKSUM);
1664                         break;
1665                 case Opt_journal_async_commit:
1666                         set_opt(sb, JOURNAL_ASYNC_COMMIT);
1667                         set_opt(sb, JOURNAL_CHECKSUM);
1668                         break;
1669                 case Opt_noload:
1670                         set_opt(sb, NOLOAD);
1671                         break;
1672                 case Opt_commit:
1673                         if (match_int(&args[0], &option))
1674                                 return 0;
1675                         if (option < 0)
1676                                 return 0;
1677                         if (option == 0)
1678                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1679                         sbi->s_commit_interval = HZ * option;
1680                         break;
1681                 case Opt_max_batch_time:
1682                         if (match_int(&args[0], &option))
1683                                 return 0;
1684                         if (option < 0)
1685                                 return 0;
1686                         if (option == 0)
1687                                 option = EXT4_DEF_MAX_BATCH_TIME;
1688                         sbi->s_max_batch_time = option;
1689                         break;
1690                 case Opt_min_batch_time:
1691                         if (match_int(&args[0], &option))
1692                                 return 0;
1693                         if (option < 0)
1694                                 return 0;
1695                         sbi->s_min_batch_time = option;
1696                         break;
1697                 case Opt_data_journal:
1698                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1699                         goto datacheck;
1700                 case Opt_data_ordered:
1701                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1702                         goto datacheck;
1703                 case Opt_data_writeback:
1704                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1705                 datacheck:
1706                         if (is_remount) {
1707                                 if (!sbi->s_journal)
1708                                         ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1709                                 else if (test_opt(sb, DATA_FLAGS) != data_opt) {
1710                                         ext4_msg(sb, KERN_ERR,
1711                                                 "Cannot change data mode on remount");
1712                                         return 0;
1713                                 }
1714                         } else {
1715                                 clear_opt(sb, DATA_FLAGS);
1716                                 sbi->s_mount_opt |= data_opt;
1717                         }
1718                         break;
1719                 case Opt_data_err_abort:
1720                         set_opt(sb, DATA_ERR_ABORT);
1721                         break;
1722                 case Opt_data_err_ignore:
1723                         clear_opt(sb, DATA_ERR_ABORT);
1724                         break;
1725 #ifdef CONFIG_QUOTA
1726                 case Opt_usrjquota:
1727                         if (!set_qf_name(sb, USRQUOTA, &args[0]))
1728                                 return 0;
1729                         break;
1730                 case Opt_grpjquota:
1731                         if (!set_qf_name(sb, GRPQUOTA, &args[0]))
1732                                 return 0;
1733                         break;
1734                 case Opt_offusrjquota:
1735                         if (!clear_qf_name(sb, USRQUOTA))
1736                                 return 0;
1737                         break;
1738                 case Opt_offgrpjquota:
1739                         if (!clear_qf_name(sb, GRPQUOTA))
1740                                 return 0;
1741                         break;
1742
1743                 case Opt_jqfmt_vfsold:
1744                         qfmt = QFMT_VFS_OLD;
1745                         goto set_qf_format;
1746                 case Opt_jqfmt_vfsv0:
1747                         qfmt = QFMT_VFS_V0;
1748                         goto set_qf_format;
1749                 case Opt_jqfmt_vfsv1:
1750                         qfmt = QFMT_VFS_V1;
1751 set_qf_format:
1752                         if (sb_any_quota_loaded(sb) &&
1753                             sbi->s_jquota_fmt != qfmt) {
1754                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1755                                         "journaled quota options when "
1756                                         "quota turned on");
1757                                 return 0;
1758                         }
1759                         sbi->s_jquota_fmt = qfmt;
1760                         break;
1761                 case Opt_quota:
1762                 case Opt_usrquota:
1763                         set_opt(sb, QUOTA);
1764                         set_opt(sb, USRQUOTA);
1765                         break;
1766                 case Opt_grpquota:
1767                         set_opt(sb, QUOTA);
1768                         set_opt(sb, GRPQUOTA);
1769                         break;
1770                 case Opt_noquota:
1771                         if (sb_any_quota_loaded(sb)) {
1772                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1773                                         "options when quota turned on");
1774                                 return 0;
1775                         }
1776                         clear_opt(sb, QUOTA);
1777                         clear_opt(sb, USRQUOTA);
1778                         clear_opt(sb, GRPQUOTA);
1779                         break;
1780 #else
1781                 case Opt_quota:
1782                 case Opt_usrquota:
1783                 case Opt_grpquota:
1784                         ext4_msg(sb, KERN_ERR,
1785                                 "quota options not supported");
1786                         break;
1787                 case Opt_usrjquota:
1788                 case Opt_grpjquota:
1789                 case Opt_offusrjquota:
1790                 case Opt_offgrpjquota:
1791                 case Opt_jqfmt_vfsold:
1792                 case Opt_jqfmt_vfsv0:
1793                 case Opt_jqfmt_vfsv1:
1794                         ext4_msg(sb, KERN_ERR,
1795                                 "journaled quota options not supported");
1796                         break;
1797                 case Opt_noquota:
1798                         break;
1799 #endif
1800                 case Opt_abort:
1801                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1802                         break;
1803                 case Opt_nobarrier:
1804                         clear_opt(sb, BARRIER);
1805                         break;
1806                 case Opt_barrier:
1807                         if (args[0].from) {
1808                                 if (match_int(&args[0], &option))
1809                                         return 0;
1810                         } else
1811                                 option = 1;     /* No argument, default to 1 */
1812                         if (option)
1813                                 set_opt(sb, BARRIER);
1814                         else
1815                                 clear_opt(sb, BARRIER);
1816                         break;
1817                 case Opt_ignore:
1818                         break;
1819                 case Opt_resize:
1820                         if (!is_remount) {
1821                                 ext4_msg(sb, KERN_ERR,
1822                                         "resize option only available "
1823                                         "for remount");
1824                                 return 0;
1825                         }
1826                         if (match_int(&args[0], &option) != 0)
1827                                 return 0;
1828                         *n_blocks_count = option;
1829                         break;
1830                 case Opt_nobh:
1831                         ext4_msg(sb, KERN_WARNING,
1832                                  "Ignoring deprecated nobh option");
1833                         break;
1834                 case Opt_bh:
1835                         ext4_msg(sb, KERN_WARNING,
1836                                  "Ignoring deprecated bh option");
1837                         break;
1838                 case Opt_i_version:
1839                         set_opt(sb, I_VERSION);
1840                         sb->s_flags |= MS_I_VERSION;
1841                         break;
1842                 case Opt_nodelalloc:
1843                         clear_opt(sb, DELALLOC);
1844                         clear_opt2(sb, EXPLICIT_DELALLOC);
1845                         break;
1846                 case Opt_mblk_io_submit:
1847                         set_opt(sb, MBLK_IO_SUBMIT);
1848                         break;
1849                 case Opt_nomblk_io_submit:
1850                         clear_opt(sb, MBLK_IO_SUBMIT);
1851                         break;
1852                 case Opt_stripe:
1853                         if (match_int(&args[0], &option))
1854                                 return 0;
1855                         if (option < 0)
1856                                 return 0;
1857                         sbi->s_stripe = option;
1858                         break;
1859                 case Opt_delalloc:
1860                         set_opt(sb, DELALLOC);
1861                         set_opt2(sb, EXPLICIT_DELALLOC);
1862                         break;
1863                 case Opt_block_validity:
1864                         set_opt(sb, BLOCK_VALIDITY);
1865                         break;
1866                 case Opt_noblock_validity:
1867                         clear_opt(sb, BLOCK_VALIDITY);
1868                         break;
1869                 case Opt_inode_readahead_blks:
1870                         if (match_int(&args[0], &option))
1871                                 return 0;
1872                         if (option < 0 || option > (1 << 30))
1873                                 return 0;
1874                         if (option && !is_power_of_2(option)) {
1875                                 ext4_msg(sb, KERN_ERR,
1876                                          "EXT4-fs: inode_readahead_blks"
1877                                          " must be a power of 2");
1878                                 return 0;
1879                         }
1880                         sbi->s_inode_readahead_blks = option;
1881                         break;
1882                 case Opt_journal_ioprio:
1883                         if (match_int(&args[0], &option))
1884                                 return 0;
1885                         if (option < 0 || option > 7)
1886                                 break;
1887                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1888                                                             option);
1889                         break;
1890                 case Opt_noauto_da_alloc:
1891                         set_opt(sb, NO_AUTO_DA_ALLOC);
1892                         break;
1893                 case Opt_auto_da_alloc:
1894                         if (args[0].from) {
1895                                 if (match_int(&args[0], &option))
1896                                         return 0;
1897                         } else
1898                                 option = 1;     /* No argument, default to 1 */
1899                         if (option)
1900                                 clear_opt(sb, NO_AUTO_DA_ALLOC);
1901                         else
1902                                 set_opt(sb,NO_AUTO_DA_ALLOC);
1903                         break;
1904                 case Opt_discard:
1905                         set_opt(sb, DISCARD);
1906                         break;
1907                 case Opt_nodiscard:
1908                         clear_opt(sb, DISCARD);
1909                         break;
1910                 case Opt_dioread_nolock:
1911                         set_opt(sb, DIOREAD_NOLOCK);
1912                         break;
1913                 case Opt_dioread_lock:
1914                         clear_opt(sb, DIOREAD_NOLOCK);
1915                         break;
1916                 case Opt_init_itable:
1917                         set_opt(sb, INIT_INODE_TABLE);
1918                         if (args[0].from) {
1919                                 if (match_int(&args[0], &option))
1920                                         return 0;
1921                         } else
1922                                 option = EXT4_DEF_LI_WAIT_MULT;
1923                         if (option < 0)
1924                                 return 0;
1925                         sbi->s_li_wait_mult = option;
1926                         break;
1927                 case Opt_noinit_itable:
1928                         clear_opt(sb, INIT_INODE_TABLE);
1929                         break;
1930                 default:
1931                         ext4_msg(sb, KERN_ERR,
1932                                "Unrecognized mount option \"%s\" "
1933                                "or missing value", p);
1934                         return 0;
1935                 }
1936         }
1937 #ifdef CONFIG_QUOTA
1938         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1939                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1940                         clear_opt(sb, USRQUOTA);
1941
1942                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1943                         clear_opt(sb, GRPQUOTA);
1944
1945                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1946                         ext4_msg(sb, KERN_ERR, "old and new quota "
1947                                         "format mixing");
1948                         return 0;
1949                 }
1950
1951                 if (!sbi->s_jquota_fmt) {
1952                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1953                                         "not specified");
1954                         return 0;
1955                 }
1956         } else {
1957                 if (sbi->s_jquota_fmt) {
1958                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1959                                         "specified with no journaling "
1960                                         "enabled");
1961                         return 0;
1962                 }
1963         }
1964 #endif
1965         return 1;
1966 }
1967
1968 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1969                             int read_only)
1970 {
1971         struct ext4_sb_info *sbi = EXT4_SB(sb);
1972         int res = 0;
1973
1974         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1975                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1976                          "forcing read-only mode");
1977                 res = MS_RDONLY;
1978         }
1979         if (read_only)
1980                 goto done;
1981         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1982                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1983                          "running e2fsck is recommended");
1984         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1985                 ext4_msg(sb, KERN_WARNING,
1986                          "warning: mounting fs with errors, "
1987                          "running e2fsck is recommended");
1988         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1989                  le16_to_cpu(es->s_mnt_count) >=
1990                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1991                 ext4_msg(sb, KERN_WARNING,
1992                          "warning: maximal mount count reached, "
1993                          "running e2fsck is recommended");
1994         else if (le32_to_cpu(es->s_checkinterval) &&
1995                 (le32_to_cpu(es->s_lastcheck) +
1996                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1997                 ext4_msg(sb, KERN_WARNING,
1998                          "warning: checktime reached, "
1999                          "running e2fsck is recommended");
2000         if (!sbi->s_journal)
2001                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2002         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2003                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2004         le16_add_cpu(&es->s_mnt_count, 1);
2005         es->s_mtime = cpu_to_le32(get_seconds());
2006         ext4_update_dynamic_rev(sb);
2007         if (sbi->s_journal)
2008                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
2009
2010         ext4_commit_super(sb, 1);
2011 done:
2012         if (test_opt(sb, DEBUG))
2013                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2014                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2015                         sb->s_blocksize,
2016                         sbi->s_groups_count,
2017                         EXT4_BLOCKS_PER_GROUP(sb),
2018                         EXT4_INODES_PER_GROUP(sb),
2019                         sbi->s_mount_opt, sbi->s_mount_opt2);
2020
2021         cleancache_init_fs(sb);
2022         return res;
2023 }
2024
2025 static int ext4_fill_flex_info(struct super_block *sb)
2026 {
2027         struct ext4_sb_info *sbi = EXT4_SB(sb);
2028         struct ext4_group_desc *gdp = NULL;
2029         ext4_group_t flex_group_count;
2030         ext4_group_t flex_group;
2031         unsigned int groups_per_flex = 0;
2032         size_t size;
2033         int i;
2034
2035         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2036         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2037                 sbi->s_log_groups_per_flex = 0;
2038                 return 1;
2039         }
2040         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
2041
2042         /* We allocate both existing and potentially added groups */
2043         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
2044                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
2045                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
2046         size = flex_group_count * sizeof(struct flex_groups);
2047         sbi->s_flex_groups = ext4_kvzalloc(size, GFP_KERNEL);
2048         if (sbi->s_flex_groups == NULL) {
2049                 ext4_msg(sb, KERN_ERR, "not enough memory for %u flex groups",
2050                          flex_group_count);
2051                 goto failed;
2052         }
2053
2054         for (i = 0; i < sbi->s_groups_count; i++) {
2055                 gdp = ext4_get_group_desc(sb, i, NULL);
2056
2057                 flex_group = ext4_flex_group(sbi, i);
2058                 atomic_add(ext4_free_inodes_count(sb, gdp),
2059                            &sbi->s_flex_groups[flex_group].free_inodes);
2060                 atomic_add(ext4_free_group_clusters(sb, gdp),
2061                            &sbi->s_flex_groups[flex_group].free_clusters);
2062                 atomic_add(ext4_used_dirs_count(sb, gdp),
2063                            &sbi->s_flex_groups[flex_group].used_dirs);
2064         }
2065
2066         return 1;
2067 failed:
2068         return 0;
2069 }
2070
2071 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
2072                             struct ext4_group_desc *gdp)
2073 {
2074         __u16 crc = 0;
2075
2076         if (sbi->s_es->s_feature_ro_compat &
2077             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
2078                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
2079                 __le32 le_group = cpu_to_le32(block_group);
2080
2081                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2082                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2083                 crc = crc16(crc, (__u8 *)gdp, offset);
2084                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
2085                 /* for checksum of struct ext4_group_desc do the rest...*/
2086                 if ((sbi->s_es->s_feature_incompat &
2087                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2088                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
2089                         crc = crc16(crc, (__u8 *)gdp + offset,
2090                                     le16_to_cpu(sbi->s_es->s_desc_size) -
2091                                         offset);
2092         }
2093
2094         return cpu_to_le16(crc);
2095 }
2096
2097 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
2098                                 struct ext4_group_desc *gdp)
2099 {
2100         if ((sbi->s_es->s_feature_ro_compat &
2101              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
2102             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
2103                 return 0;
2104
2105         return 1;
2106 }
2107
2108 /* Called at mount-time, super-block is locked */
2109 static int ext4_check_descriptors(struct super_block *sb,
2110                                   ext4_group_t *first_not_zeroed)
2111 {
2112         struct ext4_sb_info *sbi = EXT4_SB(sb);
2113         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2114         ext4_fsblk_t last_block;
2115         ext4_fsblk_t block_bitmap;
2116         ext4_fsblk_t inode_bitmap;
2117         ext4_fsblk_t inode_table;
2118         int flexbg_flag = 0;
2119         ext4_group_t i, grp = sbi->s_groups_count;
2120
2121         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2122                 flexbg_flag = 1;
2123
2124         ext4_debug("Checking group descriptors");
2125
2126         for (i = 0; i < sbi->s_groups_count; i++) {
2127                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2128
2129                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2130                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2131                 else
2132                         last_block = first_block +
2133                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2134
2135                 if ((grp == sbi->s_groups_count) &&
2136                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2137                         grp = i;
2138
2139                 block_bitmap = ext4_block_bitmap(sb, gdp);
2140                 if (block_bitmap < first_block || block_bitmap > last_block) {
2141                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2142                                "Block bitmap for group %u not in group "
2143                                "(block %llu)!", i, block_bitmap);
2144                         return 0;
2145                 }
2146                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2147                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2148                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2149                                "Inode bitmap for group %u not in group "
2150                                "(block %llu)!", i, inode_bitmap);
2151                         return 0;
2152                 }
2153                 inode_table = ext4_inode_table(sb, gdp);
2154                 if (inode_table < first_block ||
2155                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2156                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2157                                "Inode table for group %u not in group "
2158                                "(block %llu)!", i, inode_table);
2159                         return 0;
2160                 }
2161                 ext4_lock_group(sb, i);
2162                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
2163                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2164                                  "Checksum for group %u failed (%u!=%u)",
2165                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2166                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2167                         if (!(sb->s_flags & MS_RDONLY)) {
2168                                 ext4_unlock_group(sb, i);
2169                                 return 0;
2170                         }
2171                 }
2172                 ext4_unlock_group(sb, i);
2173                 if (!flexbg_flag)
2174                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2175         }
2176         if (NULL != first_not_zeroed)
2177                 *first_not_zeroed = grp;
2178
2179         ext4_free_blocks_count_set(sbi->s_es,
2180                                    EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2181         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2182         return 1;
2183 }
2184
2185 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2186  * the superblock) which were deleted from all directories, but held open by
2187  * a process at the time of a crash.  We walk the list and try to delete these
2188  * inodes at recovery time (only with a read-write filesystem).
2189  *
2190  * In order to keep the orphan inode chain consistent during traversal (in
2191  * case of crash during recovery), we link each inode into the superblock
2192  * orphan list_head and handle it the same way as an inode deletion during
2193  * normal operation (which journals the operations for us).
2194  *
2195  * We only do an iget() and an iput() on each inode, which is very safe if we
2196  * accidentally point at an in-use or already deleted inode.  The worst that
2197  * can happen in this case is that we get a "bit already cleared" message from
2198  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2199  * e2fsck was run on this filesystem, and it must have already done the orphan
2200  * inode cleanup for us, so we can safely abort without any further action.
2201  */
2202 static void ext4_orphan_cleanup(struct super_block *sb,
2203                                 struct ext4_super_block *es)
2204 {
2205         unsigned int s_flags = sb->s_flags;
2206         int nr_orphans = 0, nr_truncates = 0;
2207 #ifdef CONFIG_QUOTA
2208         int i;
2209 #endif
2210         if (!es->s_last_orphan) {
2211                 jbd_debug(4, "no orphan inodes to clean up\n");
2212                 return;
2213         }
2214
2215         if (bdev_read_only(sb->s_bdev)) {
2216                 ext4_msg(sb, KERN_ERR, "write access "
2217                         "unavailable, skipping orphan cleanup");
2218                 return;
2219         }
2220
2221         /* Check if feature set would not allow a r/w mount */
2222         if (!ext4_feature_set_ok(sb, 0)) {
2223                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2224                          "unknown ROCOMPAT features");
2225                 return;
2226         }
2227
2228         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2229                 if (es->s_last_orphan)
2230                         jbd_debug(1, "Errors on filesystem, "
2231                                   "clearing orphan list.\n");
2232                 es->s_last_orphan = 0;
2233                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2234                 return;
2235         }
2236
2237         if (s_flags & MS_RDONLY) {
2238                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2239                 sb->s_flags &= ~MS_RDONLY;
2240         }
2241 #ifdef CONFIG_QUOTA
2242         /* Needed for iput() to work correctly and not trash data */
2243         sb->s_flags |= MS_ACTIVE;
2244         /* Turn on quotas so that they are updated correctly */
2245         for (i = 0; i < MAXQUOTAS; i++) {
2246                 if (EXT4_SB(sb)->s_qf_names[i]) {
2247                         int ret = ext4_quota_on_mount(sb, i);
2248                         if (ret < 0)
2249                                 ext4_msg(sb, KERN_ERR,
2250                                         "Cannot turn on journaled "
2251                                         "quota: error %d", ret);
2252                 }
2253         }
2254 #endif
2255
2256         while (es->s_last_orphan) {
2257                 struct inode *inode;
2258
2259                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2260                 if (IS_ERR(inode)) {
2261                         es->s_last_orphan = 0;
2262                         break;
2263                 }
2264
2265                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2266                 dquot_initialize(inode);
2267                 if (inode->i_nlink) {
2268                         ext4_msg(sb, KERN_DEBUG,
2269                                 "%s: truncating inode %lu to %lld bytes",
2270                                 __func__, inode->i_ino, inode->i_size);
2271                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2272                                   inode->i_ino, inode->i_size);
2273                         ext4_truncate(inode);
2274                         nr_truncates++;
2275                 } else {
2276                         ext4_msg(sb, KERN_DEBUG,
2277                                 "%s: deleting unreferenced inode %lu",
2278                                 __func__, inode->i_ino);
2279                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2280                                   inode->i_ino);
2281                         nr_orphans++;
2282                 }
2283                 iput(inode);  /* The delete magic happens here! */
2284         }
2285
2286 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2287
2288         if (nr_orphans)
2289                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2290                        PLURAL(nr_orphans));
2291         if (nr_truncates)
2292                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2293                        PLURAL(nr_truncates));
2294 #ifdef CONFIG_QUOTA
2295         /* Turn quotas off */
2296         for (i = 0; i < MAXQUOTAS; i++) {
2297                 if (sb_dqopt(sb)->files[i])
2298                         dquot_quota_off(sb, i);
2299         }
2300 #endif
2301         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2302 }
2303
2304 /*
2305  * Maximal extent format file size.
2306  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2307  * extent format containers, within a sector_t, and within i_blocks
2308  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2309  * so that won't be a limiting factor.
2310  *
2311  * However there is other limiting factor. We do store extents in the form
2312  * of starting block and length, hence the resulting length of the extent
2313  * covering maximum file size must fit into on-disk format containers as
2314  * well. Given that length is always by 1 unit bigger than max unit (because
2315  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2316  *
2317  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2318  */
2319 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2320 {
2321         loff_t res;
2322         loff_t upper_limit = MAX_LFS_FILESIZE;
2323
2324         /* small i_blocks in vfs inode? */
2325         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2326                 /*
2327                  * CONFIG_LBDAF is not enabled implies the inode
2328                  * i_block represent total blocks in 512 bytes
2329                  * 32 == size of vfs inode i_blocks * 8
2330                  */
2331                 upper_limit = (1LL << 32) - 1;
2332
2333                 /* total blocks in file system block size */
2334                 upper_limit >>= (blkbits - 9);
2335                 upper_limit <<= blkbits;
2336         }
2337
2338         /*
2339          * 32-bit extent-start container, ee_block. We lower the maxbytes
2340          * by one fs block, so ee_len can cover the extent of maximum file
2341          * size
2342          */
2343         res = (1LL << 32) - 1;
2344         res <<= blkbits;
2345
2346         /* Sanity check against vm- & vfs- imposed limits */
2347         if (res > upper_limit)
2348                 res = upper_limit;
2349
2350         return res;
2351 }
2352
2353 /*
2354  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2355  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2356  * We need to be 1 filesystem block less than the 2^48 sector limit.
2357  */
2358 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2359 {
2360         loff_t res = EXT4_NDIR_BLOCKS;
2361         int meta_blocks;
2362         loff_t upper_limit;
2363         /* This is calculated to be the largest file size for a dense, block
2364          * mapped file such that the file's total number of 512-byte sectors,
2365          * including data and all indirect blocks, does not exceed (2^48 - 1).
2366          *
2367          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2368          * number of 512-byte sectors of the file.
2369          */
2370
2371         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2372                 /*
2373                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2374                  * the inode i_block field represents total file blocks in
2375                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2376                  */
2377                 upper_limit = (1LL << 32) - 1;
2378
2379                 /* total blocks in file system block size */
2380                 upper_limit >>= (bits - 9);
2381
2382         } else {
2383                 /*
2384                  * We use 48 bit ext4_inode i_blocks
2385                  * With EXT4_HUGE_FILE_FL set the i_blocks
2386                  * represent total number of blocks in
2387                  * file system block size
2388                  */
2389                 upper_limit = (1LL << 48) - 1;
2390
2391         }
2392
2393         /* indirect blocks */
2394         meta_blocks = 1;
2395         /* double indirect blocks */
2396         meta_blocks += 1 + (1LL << (bits-2));
2397         /* tripple indirect blocks */
2398         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2399
2400         upper_limit -= meta_blocks;
2401         upper_limit <<= bits;
2402
2403         res += 1LL << (bits-2);
2404         res += 1LL << (2*(bits-2));
2405         res += 1LL << (3*(bits-2));
2406         res <<= bits;
2407         if (res > upper_limit)
2408                 res = upper_limit;
2409
2410         if (res > MAX_LFS_FILESIZE)
2411                 res = MAX_LFS_FILESIZE;
2412
2413         return res;
2414 }
2415
2416 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2417                                    ext4_fsblk_t logical_sb_block, int nr)
2418 {
2419         struct ext4_sb_info *sbi = EXT4_SB(sb);
2420         ext4_group_t bg, first_meta_bg;
2421         int has_super = 0;
2422
2423         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2424
2425         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2426             nr < first_meta_bg)
2427                 return logical_sb_block + nr + 1;
2428         bg = sbi->s_desc_per_block * nr;
2429         if (ext4_bg_has_super(sb, bg))
2430                 has_super = 1;
2431
2432         return (has_super + ext4_group_first_block_no(sb, bg));
2433 }
2434
2435 /**
2436  * ext4_get_stripe_size: Get the stripe size.
2437  * @sbi: In memory super block info
2438  *
2439  * If we have specified it via mount option, then
2440  * use the mount option value. If the value specified at mount time is
2441  * greater than the blocks per group use the super block value.
2442  * If the super block value is greater than blocks per group return 0.
2443  * Allocator needs it be less than blocks per group.
2444  *
2445  */
2446 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2447 {
2448         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2449         unsigned long stripe_width =
2450                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2451         int ret;
2452
2453         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2454                 ret = sbi->s_stripe;
2455         else if (stripe_width <= sbi->s_blocks_per_group)
2456                 ret = stripe_width;
2457         else if (stride <= sbi->s_blocks_per_group)
2458                 ret = stride;
2459         else
2460                 ret = 0;
2461
2462         /*
2463          * If the stripe width is 1, this makes no sense and
2464          * we set it to 0 to turn off stripe handling code.
2465          */
2466         if (ret <= 1)
2467                 ret = 0;
2468
2469         return ret;
2470 }
2471
2472 /* sysfs supprt */
2473
2474 struct ext4_attr {
2475         struct attribute attr;
2476         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2477         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2478                          const char *, size_t);
2479         int offset;
2480 };
2481
2482 static int parse_strtoul(const char *buf,
2483                 unsigned long max, unsigned long *value)
2484 {
2485         char *endp;
2486
2487         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2488         endp = skip_spaces(endp);
2489         if (*endp || *value > max)
2490                 return -EINVAL;
2491
2492         return 0;
2493 }
2494
2495 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2496                                               struct ext4_sb_info *sbi,
2497                                               char *buf)
2498 {
2499         return snprintf(buf, PAGE_SIZE, "%llu\n",
2500                 (s64) EXT4_C2B(sbi,
2501                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2502 }
2503
2504 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2505                                          struct ext4_sb_info *sbi, char *buf)
2506 {
2507         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2508
2509         if (!sb->s_bdev->bd_part)
2510                 return snprintf(buf, PAGE_SIZE, "0\n");
2511         return snprintf(buf, PAGE_SIZE, "%lu\n",
2512                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2513                          sbi->s_sectors_written_start) >> 1);
2514 }
2515
2516 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2517                                           struct ext4_sb_info *sbi, char *buf)
2518 {
2519         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2520
2521         if (!sb->s_bdev->bd_part)
2522                 return snprintf(buf, PAGE_SIZE, "0\n");
2523         return snprintf(buf, PAGE_SIZE, "%llu\n",
2524                         (unsigned long long)(sbi->s_kbytes_written +
2525                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2526                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2527 }
2528
2529 static ssize_t extent_cache_hits_show(struct ext4_attr *a,
2530                                       struct ext4_sb_info *sbi, char *buf)
2531 {
2532         return snprintf(buf, PAGE_SIZE, "%lu\n", sbi->extent_cache_hits);
2533 }
2534
2535 static ssize_t extent_cache_misses_show(struct ext4_attr *a,
2536                                         struct ext4_sb_info *sbi, char *buf)
2537 {
2538         return snprintf(buf, PAGE_SIZE, "%lu\n", sbi->extent_cache_misses);
2539 }
2540
2541 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2542                                           struct ext4_sb_info *sbi,
2543                                           const char *buf, size_t count)
2544 {
2545         unsigned long t;
2546
2547         if (parse_strtoul(buf, 0x40000000, &t))
2548                 return -EINVAL;
2549
2550         if (t && !is_power_of_2(t))
2551                 return -EINVAL;
2552
2553         sbi->s_inode_readahead_blks = t;
2554         return count;
2555 }
2556
2557 static ssize_t sbi_ui_show(struct ext4_attr *a,
2558                            struct ext4_sb_info *sbi, char *buf)
2559 {
2560         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2561
2562         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2563 }
2564
2565 static ssize_t sbi_ui_store(struct ext4_attr *a,
2566                             struct ext4_sb_info *sbi,
2567                             const char *buf, size_t count)
2568 {
2569         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2570         unsigned long t;
2571
2572         if (parse_strtoul(buf, 0xffffffff, &t))
2573                 return -EINVAL;
2574         *ui = t;
2575         return count;
2576 }
2577
2578 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2579 static struct ext4_attr ext4_attr_##_name = {                   \
2580         .attr = {.name = __stringify(_name), .mode = _mode },   \
2581         .show   = _show,                                        \
2582         .store  = _store,                                       \
2583         .offset = offsetof(struct ext4_sb_info, _elname),       \
2584 }
2585 #define EXT4_ATTR(name, mode, show, store) \
2586 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2587
2588 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2589 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2590 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2591 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2592         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2593 #define ATTR_LIST(name) &ext4_attr_##name.attr
2594
2595 EXT4_RO_ATTR(delayed_allocation_blocks);
2596 EXT4_RO_ATTR(session_write_kbytes);
2597 EXT4_RO_ATTR(lifetime_write_kbytes);
2598 EXT4_RO_ATTR(extent_cache_hits);
2599 EXT4_RO_ATTR(extent_cache_misses);
2600 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2601                  inode_readahead_blks_store, s_inode_readahead_blks);
2602 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2603 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2604 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2605 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2606 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2607 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2608 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2609 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2610
2611 static struct attribute *ext4_attrs[] = {
2612         ATTR_LIST(delayed_allocation_blocks),
2613         ATTR_LIST(session_write_kbytes),
2614         ATTR_LIST(lifetime_write_kbytes),
2615         ATTR_LIST(extent_cache_hits),
2616         ATTR_LIST(extent_cache_misses),
2617         ATTR_LIST(inode_readahead_blks),
2618         ATTR_LIST(inode_goal),
2619         ATTR_LIST(mb_stats),
2620         ATTR_LIST(mb_max_to_scan),
2621         ATTR_LIST(mb_min_to_scan),
2622         ATTR_LIST(mb_order2_req),
2623         ATTR_LIST(mb_stream_req),
2624         ATTR_LIST(mb_group_prealloc),
2625         ATTR_LIST(max_writeback_mb_bump),
2626         NULL,
2627 };
2628
2629 /* Features this copy of ext4 supports */
2630 EXT4_INFO_ATTR(lazy_itable_init);
2631 EXT4_INFO_ATTR(batched_discard);
2632
2633 static struct attribute *ext4_feat_attrs[] = {
2634         ATTR_LIST(lazy_itable_init),
2635         ATTR_LIST(batched_discard),
2636         NULL,
2637 };
2638
2639 static ssize_t ext4_attr_show(struct kobject *kobj,
2640                               struct attribute *attr, char *buf)
2641 {
2642         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2643                                                 s_kobj);
2644         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2645
2646         return a->show ? a->show(a, sbi, buf) : 0;
2647 }
2648
2649 static ssize_t ext4_attr_store(struct kobject *kobj,
2650                                struct attribute *attr,
2651                                const char *buf, size_t len)
2652 {
2653         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2654                                                 s_kobj);
2655         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2656
2657         return a->store ? a->store(a, sbi, buf, len) : 0;
2658 }
2659
2660 static void ext4_sb_release(struct kobject *kobj)
2661 {
2662         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2663                                                 s_kobj);
2664         complete(&sbi->s_kobj_unregister);
2665 }
2666
2667 static const struct sysfs_ops ext4_attr_ops = {
2668         .show   = ext4_attr_show,
2669         .store  = ext4_attr_store,
2670 };
2671
2672 static struct kobj_type ext4_ktype = {
2673         .default_attrs  = ext4_attrs,
2674         .sysfs_ops      = &ext4_attr_ops,
2675         .release        = ext4_sb_release,
2676 };
2677
2678 static void ext4_feat_release(struct kobject *kobj)
2679 {
2680         complete(&ext4_feat->f_kobj_unregister);
2681 }
2682
2683 static struct kobj_type ext4_feat_ktype = {
2684         .default_attrs  = ext4_feat_attrs,
2685         .sysfs_ops      = &ext4_attr_ops,
2686         .release        = ext4_feat_release,
2687 };
2688
2689 /*
2690  * Check whether this filesystem can be mounted based on
2691  * the features present and the RDONLY/RDWR mount requested.
2692  * Returns 1 if this filesystem can be mounted as requested,
2693  * 0 if it cannot be.
2694  */
2695 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2696 {
2697         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2698                 ext4_msg(sb, KERN_ERR,
2699                         "Couldn't mount because of "
2700                         "unsupported optional features (%x)",
2701                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2702                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2703                 return 0;
2704         }
2705
2706         if (readonly)
2707                 return 1;
2708
2709         /* Check that feature set is OK for a read-write mount */
2710         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2711                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2712                          "unsupported optional features (%x)",
2713                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2714                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2715                 return 0;
2716         }
2717         /*
2718          * Large file size enabled file system can only be mounted
2719          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2720          */
2721         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2722                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2723                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2724                                  "cannot be mounted RDWR without "
2725                                  "CONFIG_LBDAF");
2726                         return 0;
2727                 }
2728         }
2729         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2730             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2731                 ext4_msg(sb, KERN_ERR,
2732                          "Can't support bigalloc feature without "
2733                          "extents feature\n");
2734                 return 0;
2735         }
2736         return 1;
2737 }
2738
2739 /*
2740  * This function is called once a day if we have errors logged
2741  * on the file system
2742  */
2743 static void print_daily_error_info(unsigned long arg)
2744 {
2745         struct super_block *sb = (struct super_block *) arg;
2746         struct ext4_sb_info *sbi;
2747         struct ext4_super_block *es;
2748
2749         sbi = EXT4_SB(sb);
2750         es = sbi->s_es;
2751
2752         if (es->s_error_count)
2753                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2754                          le32_to_cpu(es->s_error_count));
2755         if (es->s_first_error_time) {
2756                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2757                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2758                        (int) sizeof(es->s_first_error_func),
2759                        es->s_first_error_func,
2760                        le32_to_cpu(es->s_first_error_line));
2761                 if (es->s_first_error_ino)
2762                         printk(": inode %u",
2763                                le32_to_cpu(es->s_first_error_ino));
2764                 if (es->s_first_error_block)
2765                         printk(": block %llu", (unsigned long long)
2766                                le64_to_cpu(es->s_first_error_block));
2767                 printk("\n");
2768         }
2769         if (es->s_last_error_time) {
2770                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2771                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2772                        (int) sizeof(es->s_last_error_func),
2773                        es->s_last_error_func,
2774                        le32_to_cpu(es->s_last_error_line));
2775                 if (es->s_last_error_ino)
2776                         printk(": inode %u",
2777                                le32_to_cpu(es->s_last_error_ino));
2778                 if (es->s_last_error_block)
2779                         printk(": block %llu", (unsigned long long)
2780                                le64_to_cpu(es->s_last_error_block));
2781                 printk("\n");
2782         }
2783         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2784 }
2785
2786 /* Find next suitable group and run ext4_init_inode_table */
2787 static int ext4_run_li_request(struct ext4_li_request *elr)
2788 {
2789         struct ext4_group_desc *gdp = NULL;
2790         ext4_group_t group, ngroups;
2791         struct super_block *sb;
2792         unsigned long timeout = 0;
2793         int ret = 0;
2794
2795         sb = elr->lr_super;
2796         ngroups = EXT4_SB(sb)->s_groups_count;
2797
2798         for (group = elr->lr_next_group; group < ngroups; group++) {
2799                 gdp = ext4_get_group_desc(sb, group, NULL);
2800                 if (!gdp) {
2801                         ret = 1;
2802                         break;
2803                 }
2804
2805                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2806                         break;
2807         }
2808
2809         if (group == ngroups)
2810                 ret = 1;
2811
2812         if (!ret) {
2813                 timeout = jiffies;
2814                 ret = ext4_init_inode_table(sb, group,
2815                                             elr->lr_timeout ? 0 : 1);
2816                 if (elr->lr_timeout == 0) {
2817                         timeout = (jiffies - timeout) *
2818                                   elr->lr_sbi->s_li_wait_mult;
2819                         elr->lr_timeout = timeout;
2820                 }
2821                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2822                 elr->lr_next_group = group + 1;
2823         }
2824
2825         return ret;
2826 }
2827
2828 /*
2829  * Remove lr_request from the list_request and free the
2830  * request structure. Should be called with li_list_mtx held
2831  */
2832 static void ext4_remove_li_request(struct ext4_li_request *elr)
2833 {
2834         struct ext4_sb_info *sbi;
2835
2836         if (!elr)
2837                 return;
2838
2839         sbi = elr->lr_sbi;
2840
2841         list_del(&elr->lr_request);
2842         sbi->s_li_request = NULL;
2843         kfree(elr);
2844 }
2845
2846 static void ext4_unregister_li_request(struct super_block *sb)
2847 {
2848         mutex_lock(&ext4_li_mtx);
2849         if (!ext4_li_info) {
2850                 mutex_unlock(&ext4_li_mtx);
2851                 return;
2852         }
2853
2854         mutex_lock(&ext4_li_info->li_list_mtx);
2855         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2856         mutex_unlock(&ext4_li_info->li_list_mtx);
2857         mutex_unlock(&ext4_li_mtx);
2858 }
2859
2860 static struct task_struct *ext4_lazyinit_task;
2861
2862 /*
2863  * This is the function where ext4lazyinit thread lives. It walks
2864  * through the request list searching for next scheduled filesystem.
2865  * When such a fs is found, run the lazy initialization request
2866  * (ext4_rn_li_request) and keep track of the time spend in this
2867  * function. Based on that time we compute next schedule time of
2868  * the request. When walking through the list is complete, compute
2869  * next waking time and put itself into sleep.
2870  */
2871 static int ext4_lazyinit_thread(void *arg)
2872 {
2873         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2874         struct list_head *pos, *n;
2875         struct ext4_li_request *elr;
2876         unsigned long next_wakeup, cur;
2877
2878         BUG_ON(NULL == eli);
2879
2880 cont_thread:
2881         while (true) {
2882                 next_wakeup = MAX_JIFFY_OFFSET;
2883
2884                 mutex_lock(&eli->li_list_mtx);
2885                 if (list_empty(&eli->li_request_list)) {
2886                         mutex_unlock(&eli->li_list_mtx);
2887                         goto exit_thread;
2888                 }
2889
2890                 list_for_each_safe(pos, n, &eli->li_request_list) {
2891                         elr = list_entry(pos, struct ext4_li_request,
2892                                          lr_request);
2893
2894                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2895                                 if (ext4_run_li_request(elr) != 0) {
2896                                         /* error, remove the lazy_init job */
2897                                         ext4_remove_li_request(elr);
2898                                         continue;
2899                                 }
2900                         }
2901
2902                         if (time_before(elr->lr_next_sched, next_wakeup))
2903                                 next_wakeup = elr->lr_next_sched;
2904                 }
2905                 mutex_unlock(&eli->li_list_mtx);
2906
2907                 try_to_freeze();
2908
2909                 cur = jiffies;
2910                 if ((time_after_eq(cur, next_wakeup)) ||
2911                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2912                         cond_resched();
2913                         continue;
2914                 }
2915
2916                 schedule_timeout_interruptible(next_wakeup - cur);
2917
2918                 if (kthread_should_stop()) {
2919                         ext4_clear_request_list();
2920                         goto exit_thread;
2921                 }
2922         }
2923
2924 exit_thread:
2925         /*
2926          * It looks like the request list is empty, but we need
2927          * to check it under the li_list_mtx lock, to prevent any
2928          * additions into it, and of course we should lock ext4_li_mtx
2929          * to atomically free the list and ext4_li_info, because at
2930          * this point another ext4 filesystem could be registering
2931          * new one.
2932          */
2933         mutex_lock(&ext4_li_mtx);
2934         mutex_lock(&eli->li_list_mtx);
2935         if (!list_empty(&eli->li_request_list)) {
2936                 mutex_unlock(&eli->li_list_mtx);
2937                 mutex_unlock(&ext4_li_mtx);
2938                 goto cont_thread;
2939         }
2940         mutex_unlock(&eli->li_list_mtx);
2941         kfree(ext4_li_info);
2942         ext4_li_info = NULL;
2943         mutex_unlock(&ext4_li_mtx);
2944
2945         return 0;
2946 }
2947
2948 static void ext4_clear_request_list(void)
2949 {
2950         struct list_head *pos, *n;
2951         struct ext4_li_request *elr;
2952
2953         mutex_lock(&ext4_li_info->li_list_mtx);
2954         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2955                 elr = list_entry(pos, struct ext4_li_request,
2956                                  lr_request);
2957                 ext4_remove_li_request(elr);
2958         }
2959         mutex_unlock(&ext4_li_info->li_list_mtx);
2960 }
2961
2962 static int ext4_run_lazyinit_thread(void)
2963 {
2964         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2965                                          ext4_li_info, "ext4lazyinit");
2966         if (IS_ERR(ext4_lazyinit_task)) {
2967                 int err = PTR_ERR(ext4_lazyinit_task);
2968                 ext4_clear_request_list();
2969                 kfree(ext4_li_info);
2970                 ext4_li_info = NULL;
2971                 printk(KERN_CRIT "EXT4: error %d creating inode table "
2972                                  "initialization thread\n",
2973                                  err);
2974                 return err;
2975         }
2976         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2977         return 0;
2978 }
2979
2980 /*
2981  * Check whether it make sense to run itable init. thread or not.
2982  * If there is at least one uninitialized inode table, return
2983  * corresponding group number, else the loop goes through all
2984  * groups and return total number of groups.
2985  */
2986 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2987 {
2988         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2989         struct ext4_group_desc *gdp = NULL;
2990
2991         for (group = 0; group < ngroups; group++) {
2992                 gdp = ext4_get_group_desc(sb, group, NULL);
2993                 if (!gdp)
2994                         continue;
2995
2996                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2997                         break;
2998         }
2999
3000         return group;
3001 }
3002
3003 static int ext4_li_info_new(void)
3004 {
3005         struct ext4_lazy_init *eli = NULL;
3006
3007         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3008         if (!eli)
3009                 return -ENOMEM;
3010
3011         INIT_LIST_HEAD(&eli->li_request_list);
3012         mutex_init(&eli->li_list_mtx);
3013
3014         eli->li_state |= EXT4_LAZYINIT_QUIT;
3015
3016         ext4_li_info = eli;
3017
3018         return 0;
3019 }
3020
3021 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3022                                             ext4_group_t start)
3023 {
3024         struct ext4_sb_info *sbi = EXT4_SB(sb);
3025         struct ext4_li_request *elr;
3026         unsigned long rnd;
3027
3028         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3029         if (!elr)
3030                 return NULL;
3031
3032         elr->lr_super = sb;
3033         elr->lr_sbi = sbi;
3034         elr->lr_next_group = start;
3035
3036         /*
3037          * Randomize first schedule time of the request to
3038          * spread the inode table initialization requests
3039          * better.
3040          */
3041         get_random_bytes(&rnd, sizeof(rnd));
3042         elr->lr_next_sched = jiffies + (unsigned long)rnd %
3043                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
3044
3045         return elr;
3046 }
3047
3048 static int ext4_register_li_request(struct super_block *sb,
3049                                     ext4_group_t first_not_zeroed)
3050 {
3051         struct ext4_sb_info *sbi = EXT4_SB(sb);
3052         struct ext4_li_request *elr;
3053         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3054         int ret = 0;
3055
3056         if (sbi->s_li_request != NULL) {
3057                 /*
3058                  * Reset timeout so it can be computed again, because
3059                  * s_li_wait_mult might have changed.
3060                  */
3061                 sbi->s_li_request->lr_timeout = 0;
3062                 return 0;
3063         }
3064
3065         if (first_not_zeroed == ngroups ||
3066             (sb->s_flags & MS_RDONLY) ||
3067             !test_opt(sb, INIT_INODE_TABLE))
3068                 return 0;
3069
3070         elr = ext4_li_request_new(sb, first_not_zeroed);
3071         if (!elr)
3072                 return -ENOMEM;
3073
3074         mutex_lock(&ext4_li_mtx);
3075
3076         if (NULL == ext4_li_info) {
3077                 ret = ext4_li_info_new();
3078                 if (ret)
3079                         goto out;
3080         }
3081
3082         mutex_lock(&ext4_li_info->li_list_mtx);
3083         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3084         mutex_unlock(&ext4_li_info->li_list_mtx);
3085
3086         sbi->s_li_request = elr;
3087         /*
3088          * set elr to NULL here since it has been inserted to
3089          * the request_list and the removal and free of it is
3090          * handled by ext4_clear_request_list from now on.
3091          */
3092         elr = NULL;
3093
3094         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3095                 ret = ext4_run_lazyinit_thread();
3096                 if (ret)
3097                         goto out;
3098         }
3099 out:
3100         mutex_unlock(&ext4_li_mtx);
3101         if (ret)
3102                 kfree(elr);
3103         return ret;
3104 }
3105
3106 /*
3107  * We do not need to lock anything since this is called on
3108  * module unload.
3109  */
3110 static void ext4_destroy_lazyinit_thread(void)
3111 {
3112         /*
3113          * If thread exited earlier
3114          * there's nothing to be done.
3115          */
3116         if (!ext4_li_info || !ext4_lazyinit_task)
3117                 return;
3118
3119         kthread_stop(ext4_lazyinit_task);
3120 }
3121
3122 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3123 {
3124         char *orig_data = kstrdup(data, GFP_KERNEL);
3125         struct buffer_head *bh;
3126         struct ext4_super_block *es = NULL;
3127         struct ext4_sb_info *sbi;
3128         ext4_fsblk_t block;
3129         ext4_fsblk_t sb_block = get_sb_block(&data);
3130         ext4_fsblk_t logical_sb_block;
3131         unsigned long offset = 0;
3132         unsigned long journal_devnum = 0;
3133         unsigned long def_mount_opts;
3134         struct inode *root;
3135         char *cp;
3136         const char *descr;
3137         int ret = -ENOMEM;
3138         int blocksize, clustersize;
3139         unsigned int db_count;
3140         unsigned int i;
3141         int needs_recovery, has_huge_files, has_bigalloc;
3142         __u64 blocks_count;
3143         int err;
3144         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3145         ext4_group_t first_not_zeroed;
3146
3147         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3148         if (!sbi)
3149                 goto out_free_orig;
3150
3151         sbi->s_blockgroup_lock =
3152                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3153         if (!sbi->s_blockgroup_lock) {
3154                 kfree(sbi);
3155                 goto out_free_orig;
3156         }
3157         sb->s_fs_info = sbi;
3158         sbi->s_mount_opt = 0;
3159         sbi->s_resuid = EXT4_DEF_RESUID;
3160         sbi->s_resgid = EXT4_DEF_RESGID;
3161         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3162         sbi->s_sb_block = sb_block;
3163         if (sb->s_bdev->bd_part)
3164                 sbi->s_sectors_written_start =
3165                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3166
3167         /* Cleanup superblock name */
3168         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3169                 *cp = '!';
3170
3171         ret = -EINVAL;
3172         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3173         if (!blocksize) {
3174                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3175                 goto out_fail;
3176         }
3177
3178         /*
3179          * The ext4 superblock will not be buffer aligned for other than 1kB
3180          * block sizes.  We need to calculate the offset from buffer start.
3181          */
3182         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3183                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3184                 offset = do_div(logical_sb_block, blocksize);
3185         } else {
3186                 logical_sb_block = sb_block;
3187         }
3188
3189         if (!(bh = sb_bread(sb, logical_sb_block))) {
3190                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3191                 goto out_fail;
3192         }
3193         /*
3194          * Note: s_es must be initialized as soon as possible because
3195          *       some ext4 macro-instructions depend on its value
3196          */
3197         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3198         sbi->s_es = es;
3199         sb->s_magic = le16_to_cpu(es->s_magic);
3200         if (sb->s_magic != EXT4_SUPER_MAGIC)
3201                 goto cantfind_ext4;
3202         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3203
3204         /* Set defaults before we parse the mount options */
3205         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3206         set_opt(sb, INIT_INODE_TABLE);
3207         if (def_mount_opts & EXT4_DEFM_DEBUG)
3208                 set_opt(sb, DEBUG);
3209         if (def_mount_opts & EXT4_DEFM_BSDGROUPS) {
3210                 ext4_msg(sb, KERN_WARNING, deprecated_msg, "bsdgroups",
3211                         "2.6.38");
3212                 set_opt(sb, GRPID);
3213         }
3214         if (def_mount_opts & EXT4_DEFM_UID16)
3215                 set_opt(sb, NO_UID32);
3216         /* xattr user namespace & acls are now defaulted on */
3217 #ifdef CONFIG_EXT4_FS_XATTR
3218         set_opt(sb, XATTR_USER);
3219 #endif
3220 #if defined(CONFIG_EXT4_FS_POSIX_ACL)
3221         sb->s_flags |= MS_POSIXACL;
3222 #endif
3223         set_opt(sb, MBLK_IO_SUBMIT);
3224         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3225                 set_opt(sb, JOURNAL_DATA);
3226         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3227                 set_opt(sb, ORDERED_DATA);
3228         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3229                 set_opt(sb, WRITEBACK_DATA);
3230
3231         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3232                 set_opt(sb, ERRORS_PANIC);
3233         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3234                 set_opt(sb, ERRORS_CONT);
3235         else
3236                 set_opt(sb, ERRORS_RO);
3237         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3238                 set_opt(sb, BLOCK_VALIDITY);
3239         if (def_mount_opts & EXT4_DEFM_DISCARD)
3240                 set_opt(sb, DISCARD);
3241
3242         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
3243         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
3244         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3245         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3246         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3247
3248         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3249                 set_opt(sb, BARRIER);
3250
3251         /*
3252          * enable delayed allocation by default
3253          * Use -o nodelalloc to turn it off
3254          */
3255         if (!IS_EXT3_SB(sb) &&
3256             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3257                 set_opt(sb, DELALLOC);
3258
3259         /*
3260          * set default s_li_wait_mult for lazyinit, for the case there is
3261          * no mount option specified.
3262          */
3263         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3264
3265         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3266                            &journal_devnum, &journal_ioprio, NULL, 0)) {
3267                 ext4_msg(sb, KERN_WARNING,
3268                          "failed to parse options in superblock: %s",
3269                          sbi->s_es->s_mount_opts);
3270         }
3271         if (!parse_options((char *) data, sb, &journal_devnum,
3272                            &journal_ioprio, NULL, 0))
3273                 goto failed_mount;
3274
3275         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3276                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3277                             "with data=journal disables delayed "
3278                             "allocation and O_DIRECT support!\n");
3279                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3280                         ext4_msg(sb, KERN_ERR, "can't mount with "
3281                                  "both data=journal and delalloc");
3282                         goto failed_mount;
3283                 }
3284                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3285                         ext4_msg(sb, KERN_ERR, "can't mount with "
3286                                  "both data=journal and delalloc");
3287                         goto failed_mount;
3288                 }
3289                 if (test_opt(sb, DELALLOC))
3290                         clear_opt(sb, DELALLOC);
3291         }
3292
3293         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3294         if (test_opt(sb, DIOREAD_NOLOCK)) {
3295                 if (blocksize < PAGE_SIZE) {
3296                         ext4_msg(sb, KERN_ERR, "can't mount with "
3297                                  "dioread_nolock if block size != PAGE_SIZE");
3298                         goto failed_mount;
3299                 }
3300         }
3301
3302         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3303             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3304              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3305              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3306                 ext4_msg(sb, KERN_WARNING,
3307                        "feature flags set on rev 0 fs, "
3308                        "running e2fsck is recommended");
3309
3310         if (IS_EXT2_SB(sb)) {
3311                 if (ext2_feature_set_ok(sb))
3312                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3313                                  "using the ext4 subsystem");
3314                 else {
3315                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3316                                  "to feature incompatibilities");
3317                         goto failed_mount;
3318                 }
3319         }
3320
3321         if (IS_EXT3_SB(sb)) {
3322                 if (ext3_feature_set_ok(sb))
3323                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3324                                  "using the ext4 subsystem");
3325                 else {
3326                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3327                                  "to feature incompatibilities");
3328                         goto failed_mount;
3329                 }
3330         }
3331
3332         /*
3333          * Check feature flags regardless of the revision level, since we
3334          * previously didn't change the revision level when setting the flags,
3335          * so there is a chance incompat flags are set on a rev 0 filesystem.
3336          */
3337         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3338                 goto failed_mount;
3339
3340         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3341             blocksize > EXT4_MAX_BLOCK_SIZE) {
3342                 ext4_msg(sb, KERN_ERR,
3343                        "Unsupported filesystem blocksize %d", blocksize);
3344                 goto failed_mount;
3345         }
3346
3347         if (sb->s_blocksize != blocksize) {
3348                 /* Validate the filesystem blocksize */
3349                 if (!sb_set_blocksize(sb, blocksize)) {
3350                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3351                                         blocksize);
3352                         goto failed_mount;
3353                 }
3354
3355                 brelse(bh);
3356                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3357                 offset = do_div(logical_sb_block, blocksize);
3358                 bh = sb_bread(sb, logical_sb_block);
3359                 if (!bh) {
3360                         ext4_msg(sb, KERN_ERR,
3361                                "Can't read superblock on 2nd try");
3362                         goto failed_mount;
3363                 }
3364                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
3365                 sbi->s_es = es;
3366                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3367                         ext4_msg(sb, KERN_ERR,
3368                                "Magic mismatch, very weird!");
3369                         goto failed_mount;
3370                 }
3371         }
3372
3373         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3374                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3375         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3376                                                       has_huge_files);
3377         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3378
3379         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3380                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3381                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3382         } else {
3383                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3384                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3385                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3386                     (!is_power_of_2(sbi->s_inode_size)) ||
3387                     (sbi->s_inode_size > blocksize)) {
3388                         ext4_msg(sb, KERN_ERR,
3389                                "unsupported inode size: %d",
3390                                sbi->s_inode_size);
3391                         goto failed_mount;
3392                 }
3393                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3394                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3395         }
3396
3397         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3398         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3399                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3400                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3401                     !is_power_of_2(sbi->s_desc_size)) {
3402                         ext4_msg(sb, KERN_ERR,
3403                                "unsupported descriptor size %lu",
3404                                sbi->s_desc_size);
3405                         goto failed_mount;
3406                 }
3407         } else
3408                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3409
3410         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3411         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3412         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3413                 goto cantfind_ext4;
3414
3415         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3416         if (sbi->s_inodes_per_block == 0)
3417                 goto cantfind_ext4;
3418         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3419                                         sbi->s_inodes_per_block;
3420         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3421         sbi->s_sbh = bh;
3422         sbi->s_mount_state = le16_to_cpu(es->s_state);
3423         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3424         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3425
3426         for (i = 0; i < 4; i++)
3427                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3428         sbi->s_def_hash_version = es->s_def_hash_version;
3429         i = le32_to_cpu(es->s_flags);
3430         if (i & EXT2_FLAGS_UNSIGNED_HASH)
3431                 sbi->s_hash_unsigned = 3;
3432         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3433 #ifdef __CHAR_UNSIGNED__
3434                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3435                 sbi->s_hash_unsigned = 3;
3436 #else
3437                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3438 #endif
3439                 sb->s_dirt = 1;
3440         }
3441
3442         /* Handle clustersize */
3443         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3444         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3445                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3446         if (has_bigalloc) {
3447                 if (clustersize < blocksize) {
3448                         ext4_msg(sb, KERN_ERR,
3449                                  "cluster size (%d) smaller than "
3450                                  "block size (%d)", clustersize, blocksize);
3451                         goto failed_mount;
3452                 }
3453                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3454                         le32_to_cpu(es->s_log_block_size);
3455                 sbi->s_clusters_per_group =
3456                         le32_to_cpu(es->s_clusters_per_group);
3457                 if (sbi->s_clusters_per_group > blocksize * 8) {
3458                         ext4_msg(sb, KERN_ERR,
3459                                  "#clusters per group too big: %lu",
3460                                  sbi->s_clusters_per_group);
3461                         goto failed_mount;
3462                 }
3463                 if (sbi->s_blocks_per_group !=
3464                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3465                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3466                                  "clusters per group (%lu) inconsistent",
3467                                  sbi->s_blocks_per_group,
3468                                  sbi->s_clusters_per_group);
3469                         goto failed_mount;
3470                 }
3471         } else {
3472                 if (clustersize != blocksize) {
3473                         ext4_warning(sb, "fragment/cluster size (%d) != "
3474                                      "block size (%d)", clustersize,
3475                                      blocksize);
3476                         clustersize = blocksize;
3477                 }
3478                 if (sbi->s_blocks_per_group > blocksize * 8) {
3479                         ext4_msg(sb, KERN_ERR,
3480                                  "#blocks per group too big: %lu",
3481                                  sbi->s_blocks_per_group);
3482                         goto failed_mount;
3483                 }
3484                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3485                 sbi->s_cluster_bits = 0;
3486         }
3487         sbi->s_cluster_ratio = clustersize / blocksize;
3488
3489         if (sbi->s_inodes_per_group > blocksize * 8) {
3490                 ext4_msg(sb, KERN_ERR,
3491                        "#inodes per group too big: %lu",
3492                        sbi->s_inodes_per_group);
3493                 goto failed_mount;
3494         }
3495
3496         /*
3497          * Test whether we have more sectors than will fit in sector_t,
3498          * and whether the max offset is addressable by the page cache.
3499          */
3500         err = generic_check_addressable(sb->s_blocksize_bits,
3501                                         ext4_blocks_count(es));
3502         if (err) {
3503                 ext4_msg(sb, KERN_ERR, "filesystem"
3504                          " too large to mount safely on this system");
3505                 if (sizeof(sector_t) < 8)
3506                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3507                 ret = err;
3508                 goto failed_mount;
3509         }
3510
3511         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3512                 goto cantfind_ext4;
3513
3514         /* check blocks count against device size */
3515         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3516         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3517                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3518                        "exceeds size of device (%llu blocks)",
3519                        ext4_blocks_count(es), blocks_count);
3520                 goto failed_mount;
3521         }
3522
3523         /*
3524          * It makes no sense for the first data block to be beyond the end
3525          * of the filesystem.
3526          */
3527         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3528                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3529                          "block %u is beyond end of filesystem (%llu)",
3530                          le32_to_cpu(es->s_first_data_block),
3531                          ext4_blocks_count(es));
3532                 goto failed_mount;
3533         }
3534         blocks_count = (ext4_blocks_count(es) -
3535                         le32_to_cpu(es->s_first_data_block) +
3536                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3537         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3538         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3539                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3540                        "(block count %llu, first data block %u, "
3541                        "blocks per group %lu)", sbi->s_groups_count,
3542                        ext4_blocks_count(es),
3543                        le32_to_cpu(es->s_first_data_block),
3544                        EXT4_BLOCKS_PER_GROUP(sb));
3545                 goto failed_mount;
3546         }
3547         sbi->s_groups_count = blocks_count;
3548         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3549                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3550         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3551                    EXT4_DESC_PER_BLOCK(sb);
3552         sbi->s_group_desc = ext4_kvmalloc(db_count *
3553                                           sizeof(struct buffer_head *),
3554                                           GFP_KERNEL);
3555         if (sbi->s_group_desc == NULL) {
3556                 ext4_msg(sb, KERN_ERR, "not enough memory");
3557                 goto failed_mount;
3558         }
3559
3560         if (ext4_proc_root)
3561                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3562
3563         bgl_lock_init(sbi->s_blockgroup_lock);
3564
3565         for (i = 0; i < db_count; i++) {
3566                 block = descriptor_loc(sb, logical_sb_block, i);
3567                 sbi->s_group_desc[i] = sb_bread(sb, block);
3568                 if (!sbi->s_group_desc[i]) {
3569                         ext4_msg(sb, KERN_ERR,
3570                                "can't read group descriptor %d", i);
3571                         db_count = i;
3572                         goto failed_mount2;
3573                 }
3574         }
3575         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3576                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3577                 goto failed_mount2;
3578         }
3579         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3580                 if (!ext4_fill_flex_info(sb)) {
3581                         ext4_msg(sb, KERN_ERR,
3582                                "unable to initialize "
3583                                "flex_bg meta info!");
3584                         goto failed_mount2;
3585                 }
3586
3587         sbi->s_gdb_count = db_count;
3588         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3589         spin_lock_init(&sbi->s_next_gen_lock);
3590
3591         init_timer(&sbi->s_err_report);
3592         sbi->s_err_report.function = print_daily_error_info;
3593         sbi->s_err_report.data = (unsigned long) sb;
3594
3595         err = percpu_counter_init(&sbi->s_freeclusters_counter,
3596                         ext4_count_free_clusters(sb));
3597         if (!err) {
3598                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
3599                                 ext4_count_free_inodes(sb));
3600         }
3601         if (!err) {
3602                 err = percpu_counter_init(&sbi->s_dirs_counter,
3603                                 ext4_count_dirs(sb));
3604         }
3605         if (!err) {
3606                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0);
3607         }
3608         if (err) {
3609                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3610                 goto failed_mount3;
3611         }
3612
3613         sbi->s_stripe = ext4_get_stripe_size(sbi);
3614         sbi->s_max_writeback_mb_bump = 128;
3615
3616         /*
3617          * set up enough so that it can read an inode
3618          */
3619         if (!test_opt(sb, NOLOAD) &&
3620             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3621                 sb->s_op = &ext4_sops;
3622         else
3623                 sb->s_op = &ext4_nojournal_sops;
3624         sb->s_export_op = &ext4_export_ops;
3625         sb->s_xattr = ext4_xattr_handlers;
3626 #ifdef CONFIG_QUOTA
3627         sb->s_qcop = &ext4_qctl_operations;
3628         sb->dq_op = &ext4_quota_operations;
3629 #endif
3630         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3631
3632         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3633         mutex_init(&sbi->s_orphan_lock);
3634         sbi->s_resize_flags = 0;
3635
3636         sb->s_root = NULL;
3637
3638         needs_recovery = (es->s_last_orphan != 0 ||
3639                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3640                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3641
3642         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3643             !(sb->s_flags & MS_RDONLY))
3644                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3645                         goto failed_mount3;
3646
3647         /*
3648          * The first inode we look at is the journal inode.  Don't try
3649          * root first: it may be modified in the journal!
3650          */
3651         if (!test_opt(sb, NOLOAD) &&
3652             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3653                 if (ext4_load_journal(sb, es, journal_devnum))
3654                         goto failed_mount3;
3655         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3656               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3657                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3658                        "suppressed and not mounted read-only");
3659                 goto failed_mount_wq;
3660         } else {
3661                 clear_opt(sb, DATA_FLAGS);
3662                 sbi->s_journal = NULL;
3663                 needs_recovery = 0;
3664                 goto no_journal;
3665         }
3666
3667         if (ext4_blocks_count(es) > 0xffffffffULL &&
3668             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3669                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3670                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3671                 goto failed_mount_wq;
3672         }
3673
3674         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3675                 jbd2_journal_set_features(sbi->s_journal,
3676                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3677                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3678         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3679                 jbd2_journal_set_features(sbi->s_journal,
3680                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
3681                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3682                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3683         } else {
3684                 jbd2_journal_clear_features(sbi->s_journal,
3685                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3686                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3687         }
3688
3689         /* We have now updated the journal if required, so we can
3690          * validate the data journaling mode. */
3691         switch (test_opt(sb, DATA_FLAGS)) {
3692         case 0:
3693                 /* No mode set, assume a default based on the journal
3694                  * capabilities: ORDERED_DATA if the journal can
3695                  * cope, else JOURNAL_DATA
3696                  */
3697                 if (jbd2_journal_check_available_features
3698                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3699                         set_opt(sb, ORDERED_DATA);
3700                 else
3701                         set_opt(sb, JOURNAL_DATA);
3702                 break;
3703
3704         case EXT4_MOUNT_ORDERED_DATA:
3705         case EXT4_MOUNT_WRITEBACK_DATA:
3706                 if (!jbd2_journal_check_available_features
3707                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3708                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3709                                "requested data journaling mode");
3710                         goto failed_mount_wq;
3711                 }
3712         default:
3713                 break;
3714         }
3715         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3716
3717         /*
3718          * The journal may have updated the bg summary counts, so we
3719          * need to update the global counters.
3720          */
3721         percpu_counter_set(&sbi->s_freeclusters_counter,
3722                            ext4_count_free_clusters(sb));
3723         percpu_counter_set(&sbi->s_freeinodes_counter,
3724                            ext4_count_free_inodes(sb));
3725         percpu_counter_set(&sbi->s_dirs_counter,
3726                            ext4_count_dirs(sb));
3727         percpu_counter_set(&sbi->s_dirtyclusters_counter, 0);
3728
3729 no_journal:
3730         /*
3731          * The maximum number of concurrent works can be high and
3732          * concurrency isn't really necessary.  Limit it to 1.
3733          */
3734         EXT4_SB(sb)->dio_unwritten_wq =
3735                 alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
3736         if (!EXT4_SB(sb)->dio_unwritten_wq) {
3737                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
3738                 goto failed_mount_wq;
3739         }
3740
3741         /*
3742          * The jbd2_journal_load will have done any necessary log recovery,
3743          * so we can safely mount the rest of the filesystem now.
3744          */
3745
3746         root = ext4_iget(sb, EXT4_ROOT_INO);
3747         if (IS_ERR(root)) {
3748                 ext4_msg(sb, KERN_ERR, "get root inode failed");
3749                 ret = PTR_ERR(root);
3750                 root = NULL;
3751                 goto failed_mount4;
3752         }
3753         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3754                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3755                 iput(root);
3756                 goto failed_mount4;
3757         }
3758         sb->s_root = d_alloc_root(root);
3759         if (!sb->s_root) {
3760                 iput(root);
3761                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
3762                 ret = -ENOMEM;
3763                 goto failed_mount4;
3764         }
3765
3766         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
3767
3768         /* determine the minimum size of new large inodes, if present */
3769         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3770                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3771                                                      EXT4_GOOD_OLD_INODE_SIZE;
3772                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3773                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
3774                         if (sbi->s_want_extra_isize <
3775                             le16_to_cpu(es->s_want_extra_isize))
3776                                 sbi->s_want_extra_isize =
3777                                         le16_to_cpu(es->s_want_extra_isize);
3778                         if (sbi->s_want_extra_isize <
3779                             le16_to_cpu(es->s_min_extra_isize))
3780                                 sbi->s_want_extra_isize =
3781                                         le16_to_cpu(es->s_min_extra_isize);
3782                 }
3783         }
3784         /* Check if enough inode space is available */
3785         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3786                                                         sbi->s_inode_size) {
3787                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3788                                                        EXT4_GOOD_OLD_INODE_SIZE;
3789                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
3790                          "available");
3791         }
3792
3793         err = ext4_setup_system_zone(sb);
3794         if (err) {
3795                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3796                          "zone (%d)", err);
3797                 goto failed_mount4a;
3798         }
3799
3800         ext4_ext_init(sb);
3801         err = ext4_mb_init(sb, needs_recovery);
3802         if (err) {
3803                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3804                          err);
3805                 goto failed_mount5;
3806         }
3807
3808         err = ext4_register_li_request(sb, first_not_zeroed);
3809         if (err)
3810                 goto failed_mount6;
3811
3812         sbi->s_kobj.kset = ext4_kset;
3813         init_completion(&sbi->s_kobj_unregister);
3814         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3815                                    "%s", sb->s_id);
3816         if (err)
3817                 goto failed_mount7;
3818
3819         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3820         ext4_orphan_cleanup(sb, es);
3821         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3822         if (needs_recovery) {
3823                 ext4_msg(sb, KERN_INFO, "recovery complete");
3824                 ext4_mark_recovery_complete(sb, es);
3825         }
3826         if (EXT4_SB(sb)->s_journal) {
3827                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3828                         descr = " journalled data mode";
3829                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3830                         descr = " ordered data mode";
3831                 else
3832                         descr = " writeback data mode";
3833         } else
3834                 descr = "out journal";
3835
3836         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3837                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
3838                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
3839
3840         if (es->s_error_count)
3841                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
3842
3843         kfree(orig_data);
3844         return 0;
3845
3846 cantfind_ext4:
3847         if (!silent)
3848                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3849         goto failed_mount;
3850
3851 failed_mount7:
3852         ext4_unregister_li_request(sb);
3853 failed_mount6:
3854         ext4_mb_release(sb);
3855 failed_mount5:
3856         ext4_ext_release(sb);
3857         ext4_release_system_zone(sb);
3858 failed_mount4a:
3859         dput(sb->s_root);
3860         sb->s_root = NULL;
3861 failed_mount4:
3862         ext4_msg(sb, KERN_ERR, "mount failed");
3863         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
3864 failed_mount_wq:
3865         if (sbi->s_journal) {
3866                 jbd2_journal_destroy(sbi->s_journal);
3867                 sbi->s_journal = NULL;
3868         }
3869 failed_mount3:
3870         del_timer(&sbi->s_err_report);
3871         if (sbi->s_flex_groups)
3872                 ext4_kvfree(sbi->s_flex_groups);
3873         percpu_counter_destroy(&sbi->s_freeclusters_counter);
3874         percpu_counter_destroy(&sbi->s_freeinodes_counter);
3875         percpu_counter_destroy(&sbi->s_dirs_counter);
3876         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
3877         if (sbi->s_mmp_tsk)
3878                 kthread_stop(sbi->s_mmp_tsk);
3879 failed_mount2:
3880         for (i = 0; i < db_count; i++)
3881                 brelse(sbi->s_group_desc[i]);
3882         ext4_kvfree(sbi->s_group_desc);
3883 failed_mount:
3884         if (sbi->s_proc) {
3885                 remove_proc_entry(sb->s_id, ext4_proc_root);
3886         }
3887 #ifdef CONFIG_QUOTA
3888         for (i = 0; i < MAXQUOTAS; i++)
3889                 kfree(sbi->s_qf_names[i]);
3890 #endif
3891         ext4_blkdev_remove(sbi);
3892         brelse(bh);
3893 out_fail:
3894         sb->s_fs_info = NULL;
3895         kfree(sbi->s_blockgroup_lock);
3896         kfree(sbi);
3897 out_free_orig:
3898         kfree(orig_data);
3899         return ret;
3900 }
3901
3902 /*
3903  * Setup any per-fs journal parameters now.  We'll do this both on
3904  * initial mount, once the journal has been initialised but before we've
3905  * done any recovery; and again on any subsequent remount.
3906  */
3907 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
3908 {
3909         struct ext4_sb_info *sbi = EXT4_SB(sb);
3910
3911         journal->j_commit_interval = sbi->s_commit_interval;
3912         journal->j_min_batch_time = sbi->s_min_batch_time;
3913         journal->j_max_batch_time = sbi->s_max_batch_time;
3914
3915         write_lock(&journal->j_state_lock);
3916         if (test_opt(sb, BARRIER))
3917                 journal->j_flags |= JBD2_BARRIER;
3918         else
3919                 journal->j_flags &= ~JBD2_BARRIER;
3920         if (test_opt(sb, DATA_ERR_ABORT))
3921                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3922         else
3923                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3924         write_unlock(&journal->j_state_lock);
3925 }
3926
3927 static journal_t *ext4_get_journal(struct super_block *sb,
3928                                    unsigned int journal_inum)
3929 {
3930         struct inode *journal_inode;
3931         journal_t *journal;
3932
3933         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3934
3935         /* First, test for the existence of a valid inode on disk.  Bad
3936          * things happen if we iget() an unused inode, as the subsequent
3937          * iput() will try to delete it. */
3938
3939         journal_inode = ext4_iget(sb, journal_inum);
3940         if (IS_ERR(journal_inode)) {
3941                 ext4_msg(sb, KERN_ERR, "no journal found");
3942                 return NULL;
3943         }
3944         if (!journal_inode->i_nlink) {
3945                 make_bad_inode(journal_inode);
3946                 iput(journal_inode);
3947                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3948                 return NULL;
3949         }
3950
3951         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3952                   journal_inode, journal_inode->i_size);
3953         if (!S_ISREG(journal_inode->i_mode)) {
3954                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3955                 iput(journal_inode);
3956                 return NULL;
3957         }
3958
3959         journal = jbd2_journal_init_inode(journal_inode);
3960         if (!journal) {
3961                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3962                 iput(journal_inode);
3963                 return NULL;
3964         }
3965         journal->j_private = sb;
3966         ext4_init_journal_params(sb, journal);
3967         return journal;
3968 }
3969
3970 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3971                                        dev_t j_dev)
3972 {
3973         struct buffer_head *bh;
3974         journal_t *journal;
3975         ext4_fsblk_t start;
3976         ext4_fsblk_t len;
3977         int hblock, blocksize;
3978         ext4_fsblk_t sb_block;
3979         unsigned long offset;
3980         struct ext4_super_block *es;
3981         struct block_device *bdev;
3982
3983         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3984
3985         bdev = ext4_blkdev_get(j_dev, sb);
3986         if (bdev == NULL)
3987                 return NULL;
3988
3989         blocksize = sb->s_blocksize;
3990         hblock = bdev_logical_block_size(bdev);
3991         if (blocksize < hblock) {
3992                 ext4_msg(sb, KERN_ERR,
3993                         "blocksize too small for journal device");
3994                 goto out_bdev;
3995         }
3996
3997         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3998         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3999         set_blocksize(bdev, blocksize);
4000         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4001                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4002                        "external journal");
4003                 goto out_bdev;
4004         }
4005
4006         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
4007         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4008             !(le32_to_cpu(es->s_feature_incompat) &
4009               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4010                 ext4_msg(sb, KERN_ERR, "external journal has "
4011                                         "bad superblock");
4012                 brelse(bh);
4013                 goto out_bdev;
4014         }
4015
4016         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4017                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4018                 brelse(bh);
4019                 goto out_bdev;
4020         }
4021
4022         len = ext4_blocks_count(es);
4023         start = sb_block + 1;
4024         brelse(bh);     /* we're done with the superblock */
4025
4026         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4027                                         start, len, blocksize);
4028         if (!journal) {
4029                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4030                 goto out_bdev;
4031         }
4032         journal->j_private = sb;
4033         ll_rw_block(READ, 1, &journal->j_sb_buffer);
4034         wait_on_buffer(journal->j_sb_buffer);
4035         if (!buffer_uptodate(journal->j_sb_buffer)) {
4036                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4037                 goto out_journal;
4038         }
4039         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4040                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4041                                         "user (unsupported) - %d",
4042                         be32_to_cpu(journal->j_superblock->s_nr_users));
4043                 goto out_journal;
4044         }
4045         EXT4_SB(sb)->journal_bdev = bdev;
4046         ext4_init_journal_params(sb, journal);
4047         return journal;
4048
4049 out_journal:
4050         jbd2_journal_destroy(journal);
4051 out_bdev:
4052         ext4_blkdev_put(bdev);
4053         return NULL;
4054 }
4055
4056 static int ext4_load_journal(struct super_block *sb,
4057                              struct ext4_super_block *es,
4058                              unsigned long journal_devnum)
4059 {
4060         journal_t *journal;
4061         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4062         dev_t journal_dev;
4063         int err = 0;
4064         int really_read_only;
4065
4066         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4067
4068         if (journal_devnum &&
4069             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4070                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4071                         "numbers have changed");
4072                 journal_dev = new_decode_dev(journal_devnum);
4073         } else
4074                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4075
4076         really_read_only = bdev_read_only(sb->s_bdev);
4077
4078         /*
4079          * Are we loading a blank journal or performing recovery after a
4080          * crash?  For recovery, we need to check in advance whether we
4081          * can get read-write access to the device.
4082          */
4083         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4084                 if (sb->s_flags & MS_RDONLY) {
4085                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4086                                         "required on readonly filesystem");
4087                         if (really_read_only) {
4088                                 ext4_msg(sb, KERN_ERR, "write access "
4089                                         "unavailable, cannot proceed");
4090                                 return -EROFS;
4091                         }
4092                         ext4_msg(sb, KERN_INFO, "write access will "
4093                                "be enabled during recovery");
4094                 }
4095         }
4096
4097         if (journal_inum && journal_dev) {
4098                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4099                        "and inode journals!");
4100                 return -EINVAL;
4101         }
4102
4103         if (journal_inum) {
4104                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4105                         return -EINVAL;
4106         } else {
4107                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4108                         return -EINVAL;
4109         }
4110
4111         if (!(journal->j_flags & JBD2_BARRIER))
4112                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4113
4114         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
4115                 err = jbd2_journal_update_format(journal);
4116                 if (err)  {
4117                         ext4_msg(sb, KERN_ERR, "error updating journal");
4118                         jbd2_journal_destroy(journal);
4119                         return err;
4120                 }
4121         }
4122
4123         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4124                 err = jbd2_journal_wipe(journal, !really_read_only);
4125         if (!err) {
4126                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4127                 if (save)
4128                         memcpy(save, ((char *) es) +
4129                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4130                 err = jbd2_journal_load(journal);
4131                 if (save)
4132                         memcpy(((char *) es) + EXT4_S_ERR_START,
4133                                save, EXT4_S_ERR_LEN);
4134                 kfree(save);
4135         }
4136
4137         if (err) {
4138                 ext4_msg(sb, KERN_ERR, "error loading journal");
4139                 jbd2_journal_destroy(journal);
4140                 return err;
4141         }
4142
4143         EXT4_SB(sb)->s_journal = journal;
4144         ext4_clear_journal_err(sb, es);
4145
4146         if (!really_read_only && journal_devnum &&
4147             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4148                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4149
4150                 /* Make sure we flush the recovery flag to disk. */
4151                 ext4_commit_super(sb, 1);
4152         }
4153
4154         return 0;
4155 }
4156
4157 static int ext4_commit_super(struct super_block *sb, int sync)
4158 {
4159         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4160         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4161         int error = 0;
4162
4163         if (!sbh || block_device_ejected(sb))
4164                 return error;
4165         if (buffer_write_io_error(sbh)) {
4166                 /*
4167                  * Oh, dear.  A previous attempt to write the
4168                  * superblock failed.  This could happen because the
4169                  * USB device was yanked out.  Or it could happen to
4170                  * be a transient write error and maybe the block will
4171                  * be remapped.  Nothing we can do but to retry the
4172                  * write and hope for the best.
4173                  */
4174                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4175                        "superblock detected");
4176                 clear_buffer_write_io_error(sbh);
4177                 set_buffer_uptodate(sbh);
4178         }
4179         /*
4180          * If the file system is mounted read-only, don't update the
4181          * superblock write time.  This avoids updating the superblock
4182          * write time when we are mounting the root file system
4183          * read/only but we need to replay the journal; at that point,
4184          * for people who are east of GMT and who make their clock
4185          * tick in localtime for Windows bug-for-bug compatibility,
4186          * the clock is set in the future, and this will cause e2fsck
4187          * to complain and force a full file system check.
4188          */
4189         if (!(sb->s_flags & MS_RDONLY))
4190                 es->s_wtime = cpu_to_le32(get_seconds());
4191         if (sb->s_bdev->bd_part)
4192                 es->s_kbytes_written =
4193                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4194                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4195                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4196         else
4197                 es->s_kbytes_written =
4198                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4199         ext4_free_blocks_count_set(es,
4200                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4201                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4202         es->s_free_inodes_count =
4203                 cpu_to_le32(percpu_counter_sum_positive(
4204                                 &EXT4_SB(sb)->s_freeinodes_counter));
4205         sb->s_dirt = 0;
4206         BUFFER_TRACE(sbh, "marking dirty");
4207         mark_buffer_dirty(sbh);
4208         if (sync) {
4209                 error = sync_dirty_buffer(sbh);
4210                 if (error)
4211                         return error;
4212
4213                 error = buffer_write_io_error(sbh);
4214                 if (error) {
4215                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4216                                "superblock");
4217                         clear_buffer_write_io_error(sbh);
4218                         set_buffer_uptodate(sbh);
4219                 }
4220         }
4221         return error;
4222 }
4223
4224 /*
4225  * Have we just finished recovery?  If so, and if we are mounting (or
4226  * remounting) the filesystem readonly, then we will end up with a
4227  * consistent fs on disk.  Record that fact.
4228  */
4229 static void ext4_mark_recovery_complete(struct super_block *sb,
4230                                         struct ext4_super_block *es)
4231 {
4232         journal_t *journal = EXT4_SB(sb)->s_journal;
4233
4234         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4235                 BUG_ON(journal != NULL);
4236                 return;
4237         }
4238         jbd2_journal_lock_updates(journal);
4239         if (jbd2_journal_flush(journal) < 0)
4240                 goto out;
4241
4242         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4243             sb->s_flags & MS_RDONLY) {
4244                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4245                 ext4_commit_super(sb, 1);
4246         }
4247
4248 out:
4249         jbd2_journal_unlock_updates(journal);
4250 }
4251
4252 /*
4253  * If we are mounting (or read-write remounting) a filesystem whose journal
4254  * has recorded an error from a previous lifetime, move that error to the
4255  * main filesystem now.
4256  */
4257 static void ext4_clear_journal_err(struct super_block *sb,
4258                                    struct ext4_super_block *es)
4259 {
4260         journal_t *journal;
4261         int j_errno;
4262         const char *errstr;
4263
4264         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4265
4266         journal = EXT4_SB(sb)->s_journal;
4267
4268         /*
4269          * Now check for any error status which may have been recorded in the
4270          * journal by a prior ext4_error() or ext4_abort()
4271          */
4272
4273         j_errno = jbd2_journal_errno(journal);
4274         if (j_errno) {
4275                 char nbuf[16];
4276
4277                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4278                 ext4_warning(sb, "Filesystem error recorded "
4279                              "from previous mount: %s", errstr);
4280                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4281
4282                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4283                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4284                 ext4_commit_super(sb, 1);
4285
4286                 jbd2_journal_clear_err(journal);
4287         }
4288 }
4289
4290 /*
4291  * Force the running and committing transactions to commit,
4292  * and wait on the commit.
4293  */
4294 int ext4_force_commit(struct super_block *sb)
4295 {
4296         journal_t *journal;
4297         int ret = 0;
4298
4299         if (sb->s_flags & MS_RDONLY)
4300                 return 0;
4301
4302         journal = EXT4_SB(sb)->s_journal;
4303         if (journal) {
4304                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
4305                 ret = ext4_journal_force_commit(journal);
4306         }
4307
4308         return ret;
4309 }
4310
4311 static void ext4_write_super(struct super_block *sb)
4312 {
4313         lock_super(sb);
4314         ext4_commit_super(sb, 1);
4315         unlock_super(sb);
4316 }
4317
4318 static int ext4_sync_fs(struct super_block *sb, int wait)
4319 {
4320         int ret = 0;
4321         tid_t target;
4322         struct ext4_sb_info *sbi = EXT4_SB(sb);
4323
4324         trace_ext4_sync_fs(sb, wait);
4325         flush_workqueue(sbi->dio_unwritten_wq);
4326         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4327                 if (wait)
4328                         jbd2_log_wait_commit(sbi->s_journal, target);
4329         }
4330         return ret;
4331 }
4332
4333 /*
4334  * LVM calls this function before a (read-only) snapshot is created.  This
4335  * gives us a chance to flush the journal completely and mark the fs clean.
4336  *
4337  * Note that only this function cannot bring a filesystem to be in a clean
4338  * state independently, because ext4 prevents a new handle from being started
4339  * by @sb->s_frozen, which stays in an upper layer.  It thus needs help from
4340  * the upper layer.
4341  */
4342 static int ext4_freeze(struct super_block *sb)
4343 {
4344         int error = 0;
4345         journal_t *journal;
4346
4347         if (sb->s_flags & MS_RDONLY)
4348                 return 0;
4349
4350         journal = EXT4_SB(sb)->s_journal;
4351
4352         /* Now we set up the journal barrier. */
4353         jbd2_journal_lock_updates(journal);
4354
4355         /*
4356          * Don't clear the needs_recovery flag if we failed to flush
4357          * the journal.
4358          */
4359         error = jbd2_journal_flush(journal);
4360         if (error < 0)
4361                 goto out;
4362
4363         /* Journal blocked and flushed, clear needs_recovery flag. */
4364         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4365         error = ext4_commit_super(sb, 1);
4366 out:
4367         /* we rely on s_frozen to stop further updates */
4368         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4369         return error;
4370 }
4371
4372 /*
4373  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4374  * flag here, even though the filesystem is not technically dirty yet.
4375  */
4376 static int ext4_unfreeze(struct super_block *sb)
4377 {
4378         if (sb->s_flags & MS_RDONLY)
4379                 return 0;
4380
4381         lock_super(sb);
4382         /* Reset the needs_recovery flag before the fs is unlocked. */
4383         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4384         ext4_commit_super(sb, 1);
4385         unlock_super(sb);
4386         return 0;
4387 }
4388
4389 /*
4390  * Structure to save mount options for ext4_remount's benefit
4391  */
4392 struct ext4_mount_options {
4393         unsigned long s_mount_opt;
4394         unsigned long s_mount_opt2;
4395         uid_t s_resuid;
4396         gid_t s_resgid;
4397         unsigned long s_commit_interval;
4398         u32 s_min_batch_time, s_max_batch_time;
4399 #ifdef CONFIG_QUOTA
4400         int s_jquota_fmt;
4401         char *s_qf_names[MAXQUOTAS];
4402 #endif
4403 };
4404
4405 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4406 {
4407         struct ext4_super_block *es;
4408         struct ext4_sb_info *sbi = EXT4_SB(sb);
4409         ext4_fsblk_t n_blocks_count = 0;
4410         unsigned long old_sb_flags;
4411         struct ext4_mount_options old_opts;
4412         int enable_quota = 0;
4413         ext4_group_t g;
4414         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4415         int err = 0;
4416 #ifdef CONFIG_QUOTA
4417         int i;
4418 #endif
4419         char *orig_data = kstrdup(data, GFP_KERNEL);
4420
4421         /* Store the original options */
4422         lock_super(sb);
4423         old_sb_flags = sb->s_flags;
4424         old_opts.s_mount_opt = sbi->s_mount_opt;
4425         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4426         old_opts.s_resuid = sbi->s_resuid;
4427         old_opts.s_resgid = sbi->s_resgid;
4428         old_opts.s_commit_interval = sbi->s_commit_interval;
4429         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4430         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4431 #ifdef CONFIG_QUOTA
4432         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4433         for (i = 0; i < MAXQUOTAS; i++)
4434                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
4435 #endif
4436         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4437                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4438
4439         /*
4440          * Allow the "check" option to be passed as a remount option.
4441          */
4442         if (!parse_options(data, sb, NULL, &journal_ioprio,
4443                            &n_blocks_count, 1)) {
4444                 err = -EINVAL;
4445                 goto restore_opts;
4446         }
4447
4448         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4449                 ext4_abort(sb, "Abort forced by user");
4450
4451         es = sbi->s_es;
4452
4453         if (sbi->s_journal) {
4454                 ext4_init_journal_params(sb, sbi->s_journal);
4455                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4456         }
4457
4458         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
4459                 n_blocks_count > ext4_blocks_count(es)) {
4460                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4461                         err = -EROFS;
4462                         goto restore_opts;
4463                 }
4464
4465                 if (*flags & MS_RDONLY) {
4466                         err = dquot_suspend(sb, -1);
4467                         if (err < 0)
4468                                 goto restore_opts;
4469
4470                         /*
4471                          * First of all, the unconditional stuff we have to do
4472                          * to disable replay of the journal when we next remount
4473                          */
4474                         sb->s_flags |= MS_RDONLY;
4475
4476                         /*
4477                          * OK, test if we are remounting a valid rw partition
4478                          * readonly, and if so set the rdonly flag and then
4479                          * mark the partition as valid again.
4480                          */
4481                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4482                             (sbi->s_mount_state & EXT4_VALID_FS))
4483                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4484
4485                         if (sbi->s_journal)
4486                                 ext4_mark_recovery_complete(sb, es);
4487                 } else {
4488                         /* Make sure we can mount this feature set readwrite */
4489                         if (!ext4_feature_set_ok(sb, 0)) {
4490                                 err = -EROFS;
4491                                 goto restore_opts;
4492                         }
4493                         /*
4494                          * Make sure the group descriptor checksums
4495                          * are sane.  If they aren't, refuse to remount r/w.
4496                          */
4497                         for (g = 0; g < sbi->s_groups_count; g++) {
4498                                 struct ext4_group_desc *gdp =
4499                                         ext4_get_group_desc(sb, g, NULL);
4500
4501                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
4502                                         ext4_msg(sb, KERN_ERR,
4503                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4504                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4505                                                le16_to_cpu(gdp->bg_checksum));
4506                                         err = -EINVAL;
4507                                         goto restore_opts;
4508                                 }
4509                         }
4510
4511                         /*
4512                          * If we have an unprocessed orphan list hanging
4513                          * around from a previously readonly bdev mount,
4514                          * require a full umount/remount for now.
4515                          */
4516                         if (es->s_last_orphan) {
4517                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4518                                        "remount RDWR because of unprocessed "
4519                                        "orphan inode list.  Please "
4520                                        "umount/remount instead");
4521                                 err = -EINVAL;
4522                                 goto restore_opts;
4523                         }
4524
4525                         /*
4526                          * Mounting a RDONLY partition read-write, so reread
4527                          * and store the current valid flag.  (It may have
4528                          * been changed by e2fsck since we originally mounted
4529                          * the partition.)
4530                          */
4531                         if (sbi->s_journal)
4532                                 ext4_clear_journal_err(sb, es);
4533                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4534                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
4535                                 goto restore_opts;
4536                         if (!ext4_setup_super(sb, es, 0))
4537                                 sb->s_flags &= ~MS_RDONLY;
4538                         if (EXT4_HAS_INCOMPAT_FEATURE(sb,
4539                                                      EXT4_FEATURE_INCOMPAT_MMP))
4540                                 if (ext4_multi_mount_protect(sb,
4541                                                 le64_to_cpu(es->s_mmp_block))) {
4542                                         err = -EROFS;
4543                                         goto restore_opts;
4544                                 }
4545                         enable_quota = 1;
4546                 }
4547         }
4548
4549         /*
4550          * Reinitialize lazy itable initialization thread based on
4551          * current settings
4552          */
4553         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4554                 ext4_unregister_li_request(sb);
4555         else {
4556                 ext4_group_t first_not_zeroed;
4557                 first_not_zeroed = ext4_has_uninit_itable(sb);
4558                 ext4_register_li_request(sb, first_not_zeroed);
4559         }
4560
4561         ext4_setup_system_zone(sb);
4562         if (sbi->s_journal == NULL)
4563                 ext4_commit_super(sb, 1);
4564
4565 #ifdef CONFIG_QUOTA
4566         /* Release old quota file names */
4567         for (i = 0; i < MAXQUOTAS; i++)
4568                 if (old_opts.s_qf_names[i] &&
4569                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4570                         kfree(old_opts.s_qf_names[i]);
4571 #endif
4572         unlock_super(sb);
4573         if (enable_quota)
4574                 dquot_resume(sb, -1);
4575
4576         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4577         kfree(orig_data);
4578         return 0;
4579
4580 restore_opts:
4581         sb->s_flags = old_sb_flags;
4582         sbi->s_mount_opt = old_opts.s_mount_opt;
4583         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4584         sbi->s_resuid = old_opts.s_resuid;
4585         sbi->s_resgid = old_opts.s_resgid;
4586         sbi->s_commit_interval = old_opts.s_commit_interval;
4587         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4588         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4589 #ifdef CONFIG_QUOTA
4590         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4591         for (i = 0; i < MAXQUOTAS; i++) {
4592                 if (sbi->s_qf_names[i] &&
4593                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4594                         kfree(sbi->s_qf_names[i]);
4595                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4596         }
4597 #endif
4598         unlock_super(sb);
4599         kfree(orig_data);
4600         return err;
4601 }
4602
4603 /*
4604  * Note: calculating the overhead so we can be compatible with
4605  * historical BSD practice is quite difficult in the face of
4606  * clusters/bigalloc.  This is because multiple metadata blocks from
4607  * different block group can end up in the same allocation cluster.
4608  * Calculating the exact overhead in the face of clustered allocation
4609  * requires either O(all block bitmaps) in memory or O(number of block
4610  * groups**2) in time.  We will still calculate the superblock for
4611  * older file systems --- and if we come across with a bigalloc file
4612  * system with zero in s_overhead_clusters the estimate will be close to
4613  * correct especially for very large cluster sizes --- but for newer
4614  * file systems, it's better to calculate this figure once at mkfs
4615  * time, and store it in the superblock.  If the superblock value is
4616  * present (even for non-bigalloc file systems), we will use it.
4617  */
4618 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4619 {
4620         struct super_block *sb = dentry->d_sb;
4621         struct ext4_sb_info *sbi = EXT4_SB(sb);
4622         struct ext4_super_block *es = sbi->s_es;
4623         struct ext4_group_desc *gdp;
4624         u64 fsid;
4625         s64 bfree;
4626
4627         if (test_opt(sb, MINIX_DF)) {
4628                 sbi->s_overhead_last = 0;
4629         } else if (es->s_overhead_clusters) {
4630                 sbi->s_overhead_last = le32_to_cpu(es->s_overhead_clusters);
4631         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
4632                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4633                 ext4_fsblk_t overhead = 0;
4634
4635                 /*
4636                  * Compute the overhead (FS structures).  This is constant
4637                  * for a given filesystem unless the number of block groups
4638                  * changes so we cache the previous value until it does.
4639                  */
4640
4641                 /*
4642                  * All of the blocks before first_data_block are
4643                  * overhead
4644                  */
4645                 overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4646
4647                 /*
4648                  * Add the overhead found in each block group
4649                  */
4650                 for (i = 0; i < ngroups; i++) {
4651                         gdp = ext4_get_group_desc(sb, i, NULL);
4652                         overhead += ext4_num_overhead_clusters(sb, i, gdp);
4653                         cond_resched();
4654                 }
4655                 sbi->s_overhead_last = overhead;
4656                 smp_wmb();
4657                 sbi->s_blocks_last = ext4_blocks_count(es);
4658         }
4659
4660         buf->f_type = EXT4_SUPER_MAGIC;
4661         buf->f_bsize = sb->s_blocksize;
4662         buf->f_blocks = (ext4_blocks_count(es) -
4663                          EXT4_C2B(sbi, sbi->s_overhead_last));
4664         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
4665                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
4666         /* prevent underflow in case that few free space is available */
4667         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
4668         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
4669         if (buf->f_bfree < ext4_r_blocks_count(es))
4670                 buf->f_bavail = 0;
4671         buf->f_files = le32_to_cpu(es->s_inodes_count);
4672         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4673         buf->f_namelen = EXT4_NAME_LEN;
4674         fsid = le64_to_cpup((void *)es->s_uuid) ^
4675                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4676         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4677         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4678
4679         return 0;
4680 }
4681
4682 /* Helper function for writing quotas on sync - we need to start transaction
4683  * before quota file is locked for write. Otherwise the are possible deadlocks:
4684  * Process 1                         Process 2
4685  * ext4_create()                     quota_sync()
4686  *   jbd2_journal_start()                  write_dquot()
4687  *   dquot_initialize()                         down(dqio_mutex)
4688  *     down(dqio_mutex)                    jbd2_journal_start()
4689  *
4690  */
4691
4692 #ifdef CONFIG_QUOTA
4693
4694 static inline struct inode *dquot_to_inode(struct dquot *dquot)
4695 {
4696         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
4697 }
4698
4699 static int ext4_write_dquot(struct dquot *dquot)
4700 {
4701         int ret, err;
4702         handle_t *handle;
4703         struct inode *inode;
4704
4705         inode = dquot_to_inode(dquot);
4706         handle = ext4_journal_start(inode,
4707                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4708         if (IS_ERR(handle))
4709                 return PTR_ERR(handle);
4710         ret = dquot_commit(dquot);
4711         err = ext4_journal_stop(handle);
4712         if (!ret)
4713                 ret = err;
4714         return ret;
4715 }
4716
4717 static int ext4_acquire_dquot(struct dquot *dquot)
4718 {
4719         int ret, err;
4720         handle_t *handle;
4721
4722         handle = ext4_journal_start(dquot_to_inode(dquot),
4723                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4724         if (IS_ERR(handle))
4725                 return PTR_ERR(handle);
4726         ret = dquot_acquire(dquot);
4727         err = ext4_journal_stop(handle);
4728         if (!ret)
4729                 ret = err;
4730         return ret;
4731 }
4732
4733 static int ext4_release_dquot(struct dquot *dquot)
4734 {
4735         int ret, err;
4736         handle_t *handle;
4737
4738         handle = ext4_journal_start(dquot_to_inode(dquot),
4739                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4740         if (IS_ERR(handle)) {
4741                 /* Release dquot anyway to avoid endless cycle in dqput() */
4742                 dquot_release(dquot);
4743                 return PTR_ERR(handle);
4744         }
4745         ret = dquot_release(dquot);
4746         err = ext4_journal_stop(handle);
4747         if (!ret)
4748                 ret = err;
4749         return ret;
4750 }
4751
4752 static int ext4_mark_dquot_dirty(struct dquot *dquot)
4753 {
4754         /* Are we journaling quotas? */
4755         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
4756             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
4757                 dquot_mark_dquot_dirty(dquot);
4758                 return ext4_write_dquot(dquot);
4759         } else {
4760                 return dquot_mark_dquot_dirty(dquot);
4761         }
4762 }
4763
4764 static int ext4_write_info(struct super_block *sb, int type)
4765 {
4766         int ret, err;
4767         handle_t *handle;
4768
4769         /* Data block + inode block */
4770         handle = ext4_journal_start(sb->s_root->d_inode, 2);
4771         if (IS_ERR(handle))
4772                 return PTR_ERR(handle);
4773         ret = dquot_commit_info(sb, type);
4774         err = ext4_journal_stop(handle);
4775         if (!ret)
4776                 ret = err;
4777         return ret;
4778 }
4779
4780 /*
4781  * Turn on quotas during mount time - we need to find
4782  * the quota file and such...
4783  */
4784 static int ext4_quota_on_mount(struct super_block *sb, int type)
4785 {
4786         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4787                                         EXT4_SB(sb)->s_jquota_fmt, type);
4788 }
4789
4790 /*
4791  * Standard function to be called on quota_on
4792  */
4793 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4794                          struct path *path)
4795 {
4796         int err;
4797
4798         if (!test_opt(sb, QUOTA))
4799                 return -EINVAL;
4800
4801         /* Quotafile not on the same filesystem? */
4802         if (path->dentry->d_sb != sb)
4803                 return -EXDEV;
4804         /* Journaling quota? */
4805         if (EXT4_SB(sb)->s_qf_names[type]) {
4806                 /* Quotafile not in fs root? */
4807                 if (path->dentry->d_parent != sb->s_root)
4808                         ext4_msg(sb, KERN_WARNING,
4809                                 "Quota file not on filesystem root. "
4810                                 "Journaled quota will not work");
4811         }
4812
4813         /*
4814          * When we journal data on quota file, we have to flush journal to see
4815          * all updates to the file when we bypass pagecache...
4816          */
4817         if (EXT4_SB(sb)->s_journal &&
4818             ext4_should_journal_data(path->dentry->d_inode)) {
4819                 /*
4820                  * We don't need to lock updates but journal_flush() could
4821                  * otherwise be livelocked...
4822                  */
4823                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4824                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4825                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4826                 if (err)
4827                         return err;
4828         }
4829
4830         return dquot_quota_on(sb, type, format_id, path);
4831 }
4832
4833 static int ext4_quota_off(struct super_block *sb, int type)
4834 {
4835         struct inode *inode = sb_dqopt(sb)->files[type];
4836         handle_t *handle;
4837
4838         /* Force all delayed allocation blocks to be allocated.
4839          * Caller already holds s_umount sem */
4840         if (test_opt(sb, DELALLOC))
4841                 sync_filesystem(sb);
4842
4843         if (!inode)
4844                 goto out;
4845
4846         /* Update modification times of quota files when userspace can
4847          * start looking at them */
4848         handle = ext4_journal_start(inode, 1);
4849         if (IS_ERR(handle))
4850                 goto out;
4851         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
4852         ext4_mark_inode_dirty(handle, inode);
4853         ext4_journal_stop(handle);
4854
4855 out:
4856         return dquot_quota_off(sb, type);
4857 }
4858
4859 /* Read data from quotafile - avoid pagecache and such because we cannot afford
4860  * acquiring the locks... As quota files are never truncated and quota code
4861  * itself serializes the operations (and no one else should touch the files)
4862  * we don't have to be afraid of races */
4863 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
4864                                size_t len, loff_t off)
4865 {
4866         struct inode *inode = sb_dqopt(sb)->files[type];
4867         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4868         int err = 0;
4869         int offset = off & (sb->s_blocksize - 1);
4870         int tocopy;
4871         size_t toread;
4872         struct buffer_head *bh;
4873         loff_t i_size = i_size_read(inode);
4874
4875         if (off > i_size)
4876                 return 0;
4877         if (off+len > i_size)
4878                 len = i_size-off;
4879         toread = len;
4880         while (toread > 0) {
4881                 tocopy = sb->s_blocksize - offset < toread ?
4882                                 sb->s_blocksize - offset : toread;
4883                 bh = ext4_bread(NULL, inode, blk, 0, &err);
4884                 if (err)
4885                         return err;
4886                 if (!bh)        /* A hole? */
4887                         memset(data, 0, tocopy);
4888                 else
4889                         memcpy(data, bh->b_data+offset, tocopy);
4890                 brelse(bh);
4891                 offset = 0;
4892                 toread -= tocopy;
4893                 data += tocopy;
4894                 blk++;
4895         }
4896         return len;
4897 }
4898
4899 /* Write to quotafile (we know the transaction is already started and has
4900  * enough credits) */
4901 static ssize_t ext4_quota_write(struct super_block *sb, int type,
4902                                 const char *data, size_t len, loff_t off)
4903 {
4904         struct inode *inode = sb_dqopt(sb)->files[type];
4905         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4906         int err = 0;
4907         int offset = off & (sb->s_blocksize - 1);
4908         struct buffer_head *bh;
4909         handle_t *handle = journal_current_handle();
4910
4911         if (EXT4_SB(sb)->s_journal && !handle) {
4912                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4913                         " cancelled because transaction is not started",
4914                         (unsigned long long)off, (unsigned long long)len);
4915                 return -EIO;
4916         }
4917         /*
4918          * Since we account only one data block in transaction credits,
4919          * then it is impossible to cross a block boundary.
4920          */
4921         if (sb->s_blocksize - offset < len) {
4922                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4923                         " cancelled because not block aligned",
4924                         (unsigned long long)off, (unsigned long long)len);
4925                 return -EIO;
4926         }
4927
4928         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
4929         bh = ext4_bread(handle, inode, blk, 1, &err);
4930         if (!bh)
4931                 goto out;
4932         err = ext4_journal_get_write_access(handle, bh);
4933         if (err) {
4934                 brelse(bh);
4935                 goto out;
4936         }
4937         lock_buffer(bh);
4938         memcpy(bh->b_data+offset, data, len);
4939         flush_dcache_page(bh->b_page);
4940         unlock_buffer(bh);
4941         err = ext4_handle_dirty_metadata(handle, NULL, bh);
4942         brelse(bh);
4943 out:
4944         if (err) {
4945                 mutex_unlock(&inode->i_mutex);
4946                 return err;
4947         }
4948         if (inode->i_size < off + len) {
4949                 i_size_write(inode, off + len);
4950                 EXT4_I(inode)->i_disksize = inode->i_size;
4951                 ext4_mark_inode_dirty(handle, inode);
4952         }
4953         mutex_unlock(&inode->i_mutex);
4954         return len;
4955 }
4956
4957 #endif
4958
4959 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
4960                        const char *dev_name, void *data)
4961 {
4962         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
4963 }
4964
4965 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4966 static inline void register_as_ext2(void)
4967 {
4968         int err = register_filesystem(&ext2_fs_type);
4969         if (err)
4970                 printk(KERN_WARNING
4971                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
4972 }
4973
4974 static inline void unregister_as_ext2(void)
4975 {
4976         unregister_filesystem(&ext2_fs_type);
4977 }
4978
4979 static inline int ext2_feature_set_ok(struct super_block *sb)
4980 {
4981         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
4982                 return 0;
4983         if (sb->s_flags & MS_RDONLY)
4984                 return 1;
4985         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
4986                 return 0;
4987         return 1;
4988 }
4989 MODULE_ALIAS("ext2");
4990 #else
4991 static inline void register_as_ext2(void) { }
4992 static inline void unregister_as_ext2(void) { }
4993 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
4994 #endif
4995
4996 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4997 static inline void register_as_ext3(void)
4998 {
4999         int err = register_filesystem(&ext3_fs_type);
5000         if (err)
5001                 printk(KERN_WARNING
5002                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5003 }
5004
5005 static inline void unregister_as_ext3(void)
5006 {
5007         unregister_filesystem(&ext3_fs_type);
5008 }
5009
5010 static inline int ext3_feature_set_ok(struct super_block *sb)
5011 {
5012         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
5013                 return 0;
5014         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
5015                 return 0;
5016         if (sb->s_flags & MS_RDONLY)
5017                 return 1;
5018         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
5019                 return 0;
5020         return 1;
5021 }
5022 MODULE_ALIAS("ext3");
5023 #else
5024 static inline void register_as_ext3(void) { }
5025 static inline void unregister_as_ext3(void) { }
5026 static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
5027 #endif
5028
5029 static struct file_system_type ext4_fs_type = {
5030         .owner          = THIS_MODULE,
5031         .name           = "ext4",
5032         .mount          = ext4_mount,
5033         .kill_sb        = kill_block_super,
5034         .fs_flags       = FS_REQUIRES_DEV,
5035 };
5036
5037 static int __init ext4_init_feat_adverts(void)
5038 {
5039         struct ext4_features *ef;
5040         int ret = -ENOMEM;
5041
5042         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
5043         if (!ef)
5044                 goto out;
5045
5046         ef->f_kobj.kset = ext4_kset;
5047         init_completion(&ef->f_kobj_unregister);
5048         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
5049                                    "features");
5050         if (ret) {
5051                 kfree(ef);
5052                 goto out;
5053         }
5054
5055         ext4_feat = ef;
5056         ret = 0;
5057 out:
5058         return ret;
5059 }
5060
5061 static void ext4_exit_feat_adverts(void)
5062 {
5063         kobject_put(&ext4_feat->f_kobj);
5064         wait_for_completion(&ext4_feat->f_kobj_unregister);
5065         kfree(ext4_feat);
5066 }
5067
5068 /* Shared across all ext4 file systems */
5069 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5070 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5071
5072 static int __init ext4_init_fs(void)
5073 {
5074         int i, err;
5075
5076         ext4_check_flag_values();
5077
5078         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5079                 mutex_init(&ext4__aio_mutex[i]);
5080                 init_waitqueue_head(&ext4__ioend_wq[i]);
5081         }
5082
5083         err = ext4_init_pageio();
5084         if (err)
5085                 return err;
5086         err = ext4_init_system_zone();
5087         if (err)
5088                 goto out6;
5089         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
5090         if (!ext4_kset)
5091                 goto out5;
5092         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
5093
5094         err = ext4_init_feat_adverts();
5095         if (err)
5096                 goto out4;
5097
5098         err = ext4_init_mballoc();
5099         if (err)
5100                 goto out3;
5101
5102         err = ext4_init_xattr();
5103         if (err)
5104                 goto out2;
5105         err = init_inodecache();
5106         if (err)
5107                 goto out1;
5108         register_as_ext3();
5109         register_as_ext2();
5110         err = register_filesystem(&ext4_fs_type);
5111         if (err)
5112                 goto out;
5113
5114         ext4_li_info = NULL;
5115         mutex_init(&ext4_li_mtx);
5116         return 0;
5117 out:
5118         unregister_as_ext2();
5119         unregister_as_ext3();
5120         destroy_inodecache();
5121 out1:
5122         ext4_exit_xattr();
5123 out2:
5124         ext4_exit_mballoc();
5125 out3:
5126         ext4_exit_feat_adverts();
5127 out4:
5128         if (ext4_proc_root)
5129                 remove_proc_entry("fs/ext4", NULL);
5130         kset_unregister(ext4_kset);
5131 out5:
5132         ext4_exit_system_zone();
5133 out6:
5134         ext4_exit_pageio();
5135         return err;
5136 }
5137
5138 static void __exit ext4_exit_fs(void)
5139 {
5140         ext4_destroy_lazyinit_thread();
5141         unregister_as_ext2();
5142         unregister_as_ext3();
5143         unregister_filesystem(&ext4_fs_type);
5144         destroy_inodecache();
5145         ext4_exit_xattr();
5146         ext4_exit_mballoc();
5147         ext4_exit_feat_adverts();
5148         remove_proc_entry("fs/ext4", NULL);
5149         kset_unregister(ext4_kset);
5150         ext4_exit_system_zone();
5151         ext4_exit_pageio();
5152 }
5153
5154 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5155 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5156 MODULE_LICENSE("GPL");
5157 module_init(ext4_init_fs)
5158 module_exit(ext4_exit_fs)