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 <asm/uaccess.h>
  42
  43 #include <linux/kthread.h>
  44 #include <linux/freezer.h>
  45
  46 #include "ext4.h"
  47 #include "ext4_jbd2.h"
  48 #include "xattr.h"
  49 #include "acl.h"
  50 #include "mballoc.h"
  51
  52 #define CREATE_TRACE_POINTS
  53 #include <trace/events/ext4.h>
  54
  55 static struct proc_dir_entry *ext4_proc_root;
  56 static struct kset *ext4_kset;
  57 struct ext4_lazy_init *ext4_li_info;
  58 struct mutex ext4_li_mtx;
  59 struct ext4_features *ext4_feat;
  60
  61 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  62                              unsigned long journal_devnum);
  63 static int ext4_commit_super(struct super_block *sb, int sync);
  64 static void ext4_mark_recovery_complete(struct super_block *sb,
  65                                         struct ext4_super_block *es);
  66 static void ext4_clear_journal_err(struct super_block *sb,
  67                                    struct ext4_super_block *es);
  68 static int ext4_sync_fs(struct super_block *sb, int wait);
  69 static const char *ext4_decode_error(struct super_block *sb, int errno,
  70                                      char nbuf[16]);
  71 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  72 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  73 static int ext4_unfreeze(struct super_block *sb);
  74 static void ext4_write_super(struct super_block *sb);
  75 static int ext4_freeze(struct super_block *sb);
  76 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  77                        const char *dev_name, void *data);
  78 static void ext4_destroy_lazyinit_thread(void);
  79 static void ext4_unregister_li_request(struct super_block *sb);
  80
  81 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
  82 static struct file_system_type ext3_fs_type = {
  83         .owner          = THIS_MODULE,
  84         .name           = "ext3",
  85         .mount          = ext4_mount,
  86         .kill_sb        = kill_block_super,
  87         .fs_flags       = FS_REQUIRES_DEV,
  88 };
  89 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
  90 #else
  91 #define IS_EXT3_SB(sb) (0)
  92 #endif
  93
  94 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
  95                                struct ext4_group_desc *bg)
  96 {
  97         return le32_to_cpu(bg->bg_block_bitmap_lo) |
  98                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
  99                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 100 }
 101
 102 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 103                                struct ext4_group_desc *bg)
 104 {
 105         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 106                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 107                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 108 }
 109
 110 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 111                               struct ext4_group_desc *bg)
 112 {
 113         return le32_to_cpu(bg->bg_inode_table_lo) |
 114                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 115                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 116 }
 117
 118 __u32 ext4_free_blks_count(struct super_block *sb,
 119                               struct ext4_group_desc *bg)
 120 {
 121         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 122                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 123                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 124 }
 125
 126 __u32 ext4_free_inodes_count(struct super_block *sb,
 127                               struct ext4_group_desc *bg)
 128 {
 129         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 130                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 131                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 132 }
 133
 134 __u32 ext4_used_dirs_count(struct super_block *sb,
 135                               struct ext4_group_desc *bg)
 136 {
 137         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 138                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 139                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 140 }
 141
 142 __u32 ext4_itable_unused_count(struct super_block *sb,
 143                               struct ext4_group_desc *bg)
 144 {
 145         return le16_to_cpu(bg->bg_itable_unused_lo) |
 146                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 147                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 148 }
 149
 150 void ext4_block_bitmap_set(struct super_block *sb,
 151                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 152 {
 153         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 154         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 155                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 156 }
 157
 158 void ext4_inode_bitmap_set(struct super_block *sb,
 159                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 160 {
 161         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 162         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 163                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 164 }
 165
 166 void ext4_inode_table_set(struct super_block *sb,
 167                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 168 {
 169         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 170         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 171                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 172 }
 173
 174 void ext4_free_blks_set(struct super_block *sb,
 175                           struct ext4_group_desc *bg, __u32 count)
 176 {
 177         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 178         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 179                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 180 }
 181
 182 void ext4_free_inodes_set(struct super_block *sb,
 183                           struct ext4_group_desc *bg, __u32 count)
 184 {
 185         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 186         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 187                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 188 }
 189
 190 void ext4_used_dirs_set(struct super_block *sb,
 191                           struct ext4_group_desc *bg, __u32 count)
 192 {
 193         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 194         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 195                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 196 }
 197
 198 void ext4_itable_unused_set(struct super_block *sb,
 199                           struct ext4_group_desc *bg, __u32 count)
 200 {
 201         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 202         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 203                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 204 }
 205
 206
 207 /* Just increment the non-pointer handle value */
 208 static handle_t *ext4_get_nojournal(void)
 209 {
 210         handle_t *handle = current->journal_info;
 211         unsigned long ref_cnt = (unsigned long)handle;
 212
 213         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
 214
 215         ref_cnt++;
 216         handle = (handle_t *)ref_cnt;
 217
 218         current->journal_info = handle;
 219         return handle;
 220 }
 221
 222
 223 /* Decrement the non-pointer handle value */
 224 static void ext4_put_nojournal(handle_t *handle)
 225 {
 226         unsigned long ref_cnt = (unsigned long)handle;
 227
 228         BUG_ON(ref_cnt == 0);
 229
 230         ref_cnt--;
 231         handle = (handle_t *)ref_cnt;
 232
 233         current->journal_info = handle;
 234 }
 235
 236 /*
 237  * Wrappers for jbd2_journal_start/end.
 238  *
 239  * The only special thing we need to do here is to make sure that all
 240  * journal_end calls result in the superblock being marked dirty, so
 241  * that sync() will call the filesystem's write_super callback if
 242  * appropriate.
 243  */
 244 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 245 {
 246         journal_t *journal;
 247
 248         if (sb->s_flags & MS_RDONLY)
 249                 return ERR_PTR(-EROFS);
 250
 251         vfs_check_frozen(sb, SB_FREEZE_TRANS);
 252         /* Special case here: if the journal has aborted behind our
 253          * backs (eg. EIO in the commit thread), then we still need to
 254          * take the FS itself readonly cleanly. */
 255         journal = EXT4_SB(sb)->s_journal;
 256         if (journal) {
 257                 if (is_journal_aborted(journal)) {
 258                         ext4_abort(sb, "Detected aborted journal");
 259                         return ERR_PTR(-EROFS);
 260                 }
 261                 return jbd2_journal_start(journal, nblocks);
 262         }
 263         return ext4_get_nojournal();
 264 }
 265
 266 /*
 267  * The only special thing we need to do here is to make sure that all
 268  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 269  * that sync() will call the filesystem's write_super callback if
 270  * appropriate.
 271  */
 272 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
 273 {
 274         struct super_block *sb;
 275         int err;
 276         int rc;
 277
 278         if (!ext4_handle_valid(handle)) {
 279                 ext4_put_nojournal(handle);
 280                 return 0;
 281         }
 282         sb = handle->h_transaction->t_journal->j_private;
 283         err = handle->h_err;
 284         rc = jbd2_journal_stop(handle);
 285
 286         if (!err)
 287                 err = rc;
 288         if (err)
 289                 __ext4_std_error(sb, where, line, err);
 290         return err;
 291 }
 292
 293 void ext4_journal_abort_handle(const char *caller, unsigned int line,
 294                                const char *err_fn, struct buffer_head *bh,
 295                                handle_t *handle, int err)
 296 {
 297         char nbuf[16];
 298         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 299
 300         BUG_ON(!ext4_handle_valid(handle));
 301
 302         if (bh)
 303                 BUFFER_TRACE(bh, "abort");
 304
 305         if (!handle->h_err)
 306                 handle->h_err = err;
 307
 308         if (is_handle_aborted(handle))
 309                 return;
 310
 311         printk(KERN_ERR "%s:%d: aborting transaction: %s in %s\n",
 312                caller, line, errstr, err_fn);
 313
 314         jbd2_journal_abort_handle(handle);
 315 }
 316
 317 static void __save_error_info(struct super_block *sb, const char *func,
 318                             unsigned int line)
 319 {
 320         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 321
 322         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 323         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 324         es->s_last_error_time = cpu_to_le32(get_seconds());
 325         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 326         es->s_last_error_line = cpu_to_le32(line);
 327         if (!es->s_first_error_time) {
 328                 es->s_first_error_time = es->s_last_error_time;
 329                 strncpy(es->s_first_error_func, func,
 330                         sizeof(es->s_first_error_func));
 331                 es->s_first_error_line = cpu_to_le32(line);
 332                 es->s_first_error_ino = es->s_last_error_ino;
 333                 es->s_first_error_block = es->s_last_error_block;
 334         }
 335         /*
 336          * Start the daily error reporting function if it hasn't been
 337          * started already
 338          */
 339         if (!es->s_error_count)
 340                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 341         es->s_error_count = cpu_to_le32(le32_to_cpu(es->s_error_count) + 1);
 342 }
 343
 344 static void save_error_info(struct super_block *sb, const char *func,
 345                             unsigned int line)
 346 {
 347         __save_error_info(sb, func, line);
 348         ext4_commit_super(sb, 1);
 349 }
 350
 351
 352 /* Deal with the reporting of failure conditions on a filesystem such as
 353  * inconsistencies detected or read IO failures.
 354  *
 355  * On ext2, we can store the error state of the filesystem in the
 356  * superblock.  That is not possible on ext4, because we may have other
 357  * write ordering constraints on the superblock which prevent us from
 358  * writing it out straight away; and given that the journal is about to
 359  * be aborted, we can't rely on the current, or future, transactions to
 360  * write out the superblock safely.
 361  *
 362  * We'll just use the jbd2_journal_abort() error code to record an error in
 363  * the journal instead.  On recovery, the journal will complain about
 364  * that error until we've noted it down and cleared it.
 365  */
 366
 367 static void ext4_handle_error(struct super_block *sb)
 368 {
 369         if (sb->s_flags & MS_RDONLY)
 370                 return;
 371
 372         if (!test_opt(sb, ERRORS_CONT)) {
 373                 journal_t *journal = EXT4_SB(sb)->s_journal;
 374
 375                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 376                 if (journal)
 377                         jbd2_journal_abort(journal, -EIO);
 378         }
 379         if (test_opt(sb, ERRORS_RO)) {
 380                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 381                 sb->s_flags |= MS_RDONLY;
 382         }
 383         if (test_opt(sb, ERRORS_PANIC))
 384                 panic("EXT4-fs (device %s): panic forced after error\n",
 385                         sb->s_id);
 386 }
 387
 388 void __ext4_error(struct super_block *sb, const char *function,
 389                   unsigned int line, const char *fmt, ...)
 390 {
 391         va_list args;
 392
 393         va_start(args, fmt);
 394         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: ",
 395                sb->s_id, function, line, current->comm);
 396         vprintk(fmt, args);
 397         printk("\n");
 398         va_end(args);
 399
 400         ext4_handle_error(sb);
 401 }
 402
 403 void ext4_error_inode(struct inode *inode, const char *function,
 404                       unsigned int line, ext4_fsblk_t block,
 405                       const char *fmt, ...)
 406 {
 407         va_list args;
 408         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 409
 410         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 411         es->s_last_error_block = cpu_to_le64(block);
 412         save_error_info(inode->i_sb, function, line);
 413         va_start(args, fmt);
 414         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: inode #%lu: ",
 415                inode->i_sb->s_id, function, line, inode->i_ino);
 416         if (block)
 417                 printk("block %llu: ", block);
 418         printk("comm %s: ", current->comm);
 419         vprintk(fmt, args);
 420         printk("\n");
 421         va_end(args);
 422
 423         ext4_handle_error(inode->i_sb);
 424 }
 425
 426 void ext4_error_file(struct file *file, const char *function,
 427                      unsigned int line, const char *fmt, ...)
 428 {
 429         va_list args;
 430         struct ext4_super_block *es;
 431         struct inode *inode = file->f_dentry->d_inode;
 432         char pathname[80], *path;
 433
 434         es = EXT4_SB(inode->i_sb)->s_es;
 435         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 436         save_error_info(inode->i_sb, function, line);
 437         va_start(args, fmt);
 438         path = d_path(&(file->f_path), pathname, sizeof(pathname));
 439         if (!path)
 440                 path = "(unknown)";
 441         printk(KERN_CRIT
 442                "EXT4-fs error (device %s): %s:%d: inode #%lu "
 443                "(comm %s path %s): ",
 444                inode->i_sb->s_id, function, line, inode->i_ino,
 445                current->comm, path);
 446         vprintk(fmt, args);
 447         printk("\n");
 448         va_end(args);
 449
 450         ext4_handle_error(inode->i_sb);
 451 }
 452
 453 static const char *ext4_decode_error(struct super_block *sb, int errno,
 454                                      char nbuf[16])
 455 {
 456         char *errstr = NULL;
 457
 458         switch (errno) {
 459         case -EIO:
 460                 errstr = "IO failure";
 461                 break;
 462         case -ENOMEM:
 463                 errstr = "Out of memory";
 464                 break;
 465         case -EROFS:
 466                 if (!sb || (EXT4_SB(sb)->s_journal &&
 467                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 468                         errstr = "Journal has aborted";
 469                 else
 470                         errstr = "Readonly filesystem";
 471                 break;
 472         default:
 473                 /* If the caller passed in an extra buffer for unknown
 474                  * errors, textualise them now.  Else we just return
 475                  * NULL. */
 476                 if (nbuf) {
 477                         /* Check for truncated error codes... */
 478                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 479                                 errstr = nbuf;
 480                 }
 481                 break;
 482         }
 483
 484         return errstr;
 485 }
 486
 487 /* __ext4_std_error decodes expected errors from journaling functions
 488  * automatically and invokes the appropriate error response.  */
 489
 490 void __ext4_std_error(struct super_block *sb, const char *function,
 491                       unsigned int line, int errno)
 492 {
 493         char nbuf[16];
 494         const char *errstr;
 495
 496         /* Special case: if the error is EROFS, and we're not already
 497          * inside a transaction, then there's really no point in logging
 498          * an error. */
 499         if (errno == -EROFS && journal_current_handle() == NULL &&
 500             (sb->s_flags & MS_RDONLY))
 501                 return;
 502
 503         errstr = ext4_decode_error(sb, errno, nbuf);
 504         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 505                sb->s_id, function, line, errstr);
 506         save_error_info(sb, function, line);
 507
 508         ext4_handle_error(sb);
 509 }
 510
 511 /*
 512  * ext4_abort is a much stronger failure handler than ext4_error.  The
 513  * abort function may be used to deal with unrecoverable failures such
 514  * as journal IO errors or ENOMEM at a critical moment in log management.
 515  *
 516  * We unconditionally force the filesystem into an ABORT|READONLY state,
 517  * unless the error response on the fs has been set to panic in which
 518  * case we take the easy way out and panic immediately.
 519  */
 520
 521 void __ext4_abort(struct super_block *sb, const char *function,
 522                 unsigned int line, const char *fmt, ...)
 523 {
 524         va_list args;
 525
 526         save_error_info(sb, function, line);
 527         va_start(args, fmt);
 528         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 529                function, line);
 530         vprintk(fmt, args);
 531         printk("\n");
 532         va_end(args);
 533
 534         if ((sb->s_flags & MS_RDONLY) == 0) {
 535                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 536                 sb->s_flags |= MS_RDONLY;
 537                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 538                 if (EXT4_SB(sb)->s_journal)
 539                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 540                 save_error_info(sb, function, line);
 541         }
 542         if (test_opt(sb, ERRORS_PANIC))
 543                 panic("EXT4-fs panic from previous error\n");
 544 }
 545
 546 void ext4_msg (struct super_block * sb, const char *prefix,
 547                    const char *fmt, ...)
 548 {
 549         va_list args;
 550
 551         va_start(args, fmt);
 552         printk("%sEXT4-fs (%s): ", prefix, sb->s_id);
 553         vprintk(fmt, args);
 554         printk("\n");
 555         va_end(args);
 556 }
 557
 558 void __ext4_warning(struct super_block *sb, const char *function,
 559                     unsigned int line, const char *fmt, ...)
 560 {
 561         va_list args;
 562
 563         va_start(args, fmt);
 564         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: ",
 565                sb->s_id, function, line);
 566         vprintk(fmt, args);
 567         printk("\n");
 568         va_end(args);
 569 }
 570
 571 void __ext4_grp_locked_error(const char *function, unsigned int line,
 572                              struct super_block *sb, ext4_group_t grp,
 573                              unsigned long ino, ext4_fsblk_t block,
 574                              const char *fmt, ...)
 575 __releases(bitlock)
 576 __acquires(bitlock)
 577 {
 578         va_list args;
 579         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 580
 581         es->s_last_error_ino = cpu_to_le32(ino);
 582         es->s_last_error_block = cpu_to_le64(block);
 583         __save_error_info(sb, function, line);
 584         va_start(args, fmt);
 585         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u",
 586                sb->s_id, function, line, grp);
 587         if (ino)
 588                 printk("inode %lu: ", ino);
 589         if (block)
 590                 printk("block %llu:", (unsigned long long) block);
 591         vprintk(fmt, args);
 592         printk("\n");
 593         va_end(args);
 594
 595         if (test_opt(sb, ERRORS_CONT)) {
 596                 ext4_commit_super(sb, 0);
 597                 return;
 598         }
 599
 600         ext4_unlock_group(sb, grp);
 601         ext4_handle_error(sb);
 602         /*
 603          * We only get here in the ERRORS_RO case; relocking the group
 604          * may be dangerous, but nothing bad will happen since the
 605          * filesystem will have already been marked read/only and the
 606          * journal has been aborted.  We return 1 as a hint to callers
 607          * who might what to use the return value from
 608          * ext4_grp_locked_error() to distinguish beween the
 609          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 610          * aggressively from the ext4 function in question, with a
 611          * more appropriate error code.
 612          */
 613         ext4_lock_group(sb, grp);
 614         return;
 615 }
 616
 617 void ext4_update_dynamic_rev(struct super_block *sb)
 618 {
 619         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 620
 621         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 622                 return;
 623
 624         ext4_warning(sb,
 625                      "updating to rev %d because of new feature flag, "
 626                      "running e2fsck is recommended",
 627                      EXT4_DYNAMIC_REV);
 628
 629         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 630         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 631         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 632         /* leave es->s_feature_*compat flags alone */
 633         /* es->s_uuid will be set by e2fsck if empty */
 634
 635         /*
 636          * The rest of the superblock fields should be zero, and if not it
 637          * means they are likely already in use, so leave them alone.  We
 638          * can leave it up to e2fsck to clean up any inconsistencies there.
 639          */
 640 }
 641
 642 /*
 643  * Open the external journal device
 644  */
 645 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 646 {
 647         struct block_device *bdev;
 648         char b[BDEVNAME_SIZE];
 649
 650         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
 651         if (IS_ERR(bdev))
 652                 goto fail;
 653         return bdev;
 654
 655 fail:
 656         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 657                         __bdevname(dev, b), PTR_ERR(bdev));
 658         return NULL;
 659 }
 660
 661 /*
 662  * Release the journal device
 663  */
 664 static int ext4_blkdev_put(struct block_device *bdev)
 665 {
 666         bd_release(bdev);
 667         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
 668 }
 669
 670 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 671 {
 672         struct block_device *bdev;
 673         int ret = -ENODEV;
 674
 675         bdev = sbi->journal_bdev;
 676         if (bdev) {
 677                 ret = ext4_blkdev_put(bdev);
 678                 sbi->journal_bdev = NULL;
 679         }
 680         return ret;
 681 }
 682
 683 static inline struct inode *orphan_list_entry(struct list_head *l)
 684 {
 685         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 686 }
 687
 688 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 689 {
 690         struct list_head *l;
 691
 692         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 693                  le32_to_cpu(sbi->s_es->s_last_orphan));
 694
 695         printk(KERN_ERR "sb_info orphan list:\n");
 696         list_for_each(l, &sbi->s_orphan) {
 697                 struct inode *inode = orphan_list_entry(l);
 698                 printk(KERN_ERR "  "
 699                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 700                        inode->i_sb->s_id, inode->i_ino, inode,
 701                        inode->i_mode, inode->i_nlink,
 702                        NEXT_ORPHAN(inode));
 703         }
 704 }
 705
 706 static void ext4_put_super(struct super_block *sb)
 707 {
 708         struct ext4_sb_info *sbi = EXT4_SB(sb);
 709         struct ext4_super_block *es = sbi->s_es;
 710         int i, err;
 711
 712         ext4_unregister_li_request(sb);
 713         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 714
 715         flush_workqueue(sbi->dio_unwritten_wq);
 716         destroy_workqueue(sbi->dio_unwritten_wq);
 717
 718         lock_super(sb);
 719         if (sb->s_dirt)
 720                 ext4_commit_super(sb, 1);
 721
 722         if (sbi->s_journal) {
 723                 err = jbd2_journal_destroy(sbi->s_journal);
 724                 sbi->s_journal = NULL;
 725                 if (err < 0)
 726                         ext4_abort(sb, "Couldn't clean up the journal");
 727         }
 728
 729         del_timer(&sbi->s_err_report);
 730         ext4_release_system_zone(sb);
 731         ext4_mb_release(sb);
 732         ext4_ext_release(sb);
 733         ext4_xattr_put_super(sb);
 734
 735         if (!(sb->s_flags & MS_RDONLY)) {
 736                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 737                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 738                 ext4_commit_super(sb, 1);
 739         }
 740         if (sbi->s_proc) {
 741                 remove_proc_entry(sb->s_id, ext4_proc_root);
 742         }
 743         kobject_del(&sbi->s_kobj);
 744
 745         for (i = 0; i < sbi->s_gdb_count; i++)
 746                 brelse(sbi->s_group_desc[i]);
 747         kfree(sbi->s_group_desc);
 748         if (is_vmalloc_addr(sbi->s_flex_groups))
 749                 vfree(sbi->s_flex_groups);
 750         else
 751                 kfree(sbi->s_flex_groups);
 752         percpu_counter_destroy(&sbi->s_freeblocks_counter);
 753         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 754         percpu_counter_destroy(&sbi->s_dirs_counter);
 755         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
 756         brelse(sbi->s_sbh);
 757 #ifdef CONFIG_QUOTA
 758         for (i = 0; i < MAXQUOTAS; i++)
 759                 kfree(sbi->s_qf_names[i]);
 760 #endif
 761
 762         /* Debugging code just in case the in-memory inode orphan list
 763          * isn't empty.  The on-disk one can be non-empty if we've
 764          * detected an error and taken the fs readonly, but the
 765          * in-memory list had better be clean by this point. */
 766         if (!list_empty(&sbi->s_orphan))
 767                 dump_orphan_list(sb, sbi);
 768         J_ASSERT(list_empty(&sbi->s_orphan));
 769
 770         invalidate_bdev(sb->s_bdev);
 771         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 772                 /*
 773                  * Invalidate the journal device's buffers.  We don't want them
 774                  * floating about in memory - the physical journal device may
 775                  * hotswapped, and it breaks the `ro-after' testing code.
 776                  */
 777                 sync_blockdev(sbi->journal_bdev);
 778                 invalidate_bdev(sbi->journal_bdev);
 779                 ext4_blkdev_remove(sbi);
 780         }
 781         sb->s_fs_info = NULL;
 782         /*
 783          * Now that we are completely done shutting down the
 784          * superblock, we need to actually destroy the kobject.
 785          */
 786         unlock_super(sb);
 787         kobject_put(&sbi->s_kobj);
 788         wait_for_completion(&sbi->s_kobj_unregister);
 789         kfree(sbi->s_blockgroup_lock);
 790         kfree(sbi);
 791 }
 792
 793 static struct kmem_cache *ext4_inode_cachep;
 794
 795 /*
 796  * Called inside transaction, so use GFP_NOFS
 797  */
 798 static struct inode *ext4_alloc_inode(struct super_block *sb)
 799 {
 800         struct ext4_inode_info *ei;
 801
 802         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 803         if (!ei)
 804                 return NULL;
 805
 806         ei->vfs_inode.i_version = 1;
 807         ei->vfs_inode.i_data.writeback_index = 0;
 808         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 809         INIT_LIST_HEAD(&ei->i_prealloc_list);
 810         spin_lock_init(&ei->i_prealloc_lock);
 811         /*
 812          * Note:  We can be called before EXT4_SB(sb)->s_journal is set,
 813          * therefore it can be null here.  Don't check it, just initialize
 814          * jinode.
 815          */
 816         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
 817         ei->i_reserved_data_blocks = 0;
 818         ei->i_reserved_meta_blocks = 0;
 819         ei->i_allocated_meta_blocks = 0;
 820         ei->i_da_metadata_calc_len = 0;
 821         ei->i_delalloc_reserved_flag = 0;
 822         spin_lock_init(&(ei->i_block_reservation_lock));
 823 #ifdef CONFIG_QUOTA
 824         ei->i_reserved_quota = 0;
 825 #endif
 826         INIT_LIST_HEAD(&ei->i_completed_io_list);
 827         spin_lock_init(&ei->i_completed_io_lock);
 828         ei->cur_aio_dio = NULL;
 829         ei->i_sync_tid = 0;
 830         ei->i_datasync_tid = 0;
 831         atomic_set(&ei->i_ioend_count, 0);
 832
 833         return &ei->vfs_inode;
 834 }
 835
 836 static int ext4_drop_inode(struct inode *inode)
 837 {
 838         int drop = generic_drop_inode(inode);
 839
 840         trace_ext4_drop_inode(inode, drop);
 841         return drop;
 842 }
 843
 844 static void ext4_destroy_inode(struct inode *inode)
 845 {
 846         ext4_ioend_wait(inode);
 847         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 848                 ext4_msg(inode->i_sb, KERN_ERR,
 849                          "Inode %lu (%p): orphan list check failed!",
 850                          inode->i_ino, EXT4_I(inode));
 851                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 852                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 853                                 true);
 854                 dump_stack();
 855         }
 856         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 857 }
 858
 859 static void init_once(void *foo)
 860 {
 861         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 862
 863         INIT_LIST_HEAD(&ei->i_orphan);
 864 #ifdef CONFIG_EXT4_FS_XATTR
 865         init_rwsem(&ei->xattr_sem);
 866 #endif
 867         init_rwsem(&ei->i_data_sem);
 868         inode_init_once(&ei->vfs_inode);
 869 }
 870
 871 static int init_inodecache(void)
 872 {
 873         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 874                                              sizeof(struct ext4_inode_info),
 875                                              0, (SLAB_RECLAIM_ACCOUNT|
 876                                                 SLAB_MEM_SPREAD),
 877                                              init_once);
 878         if (ext4_inode_cachep == NULL)
 879                 return -ENOMEM;
 880         return 0;
 881 }
 882
 883 static void destroy_inodecache(void)
 884 {
 885         kmem_cache_destroy(ext4_inode_cachep);
 886 }
 887
 888 void ext4_clear_inode(struct inode *inode)
 889 {
 890         invalidate_inode_buffers(inode);
 891         end_writeback(inode);
 892         dquot_drop(inode);
 893         ext4_discard_preallocations(inode);
 894         if (EXT4_JOURNAL(inode))
 895                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
 896                                        &EXT4_I(inode)->jinode);
 897 }
 898
 899 static inline void ext4_show_quota_options(struct seq_file *seq,
 900                                            struct super_block *sb)
 901 {
 902 #if defined(CONFIG_QUOTA)
 903         struct ext4_sb_info *sbi = EXT4_SB(sb);
 904
 905         if (sbi->s_jquota_fmt) {
 906                 char *fmtname = "";
 907
 908                 switch (sbi->s_jquota_fmt) {
 909                 case QFMT_VFS_OLD:
 910                         fmtname = "vfsold";
 911                         break;
 912                 case QFMT_VFS_V0:
 913                         fmtname = "vfsv0";
 914                         break;
 915                 case QFMT_VFS_V1:
 916                         fmtname = "vfsv1";
 917                         break;
 918                 }
 919                 seq_printf(seq, ",jqfmt=%s", fmtname);
 920         }
 921
 922         if (sbi->s_qf_names[USRQUOTA])
 923                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
 924
 925         if (sbi->s_qf_names[GRPQUOTA])
 926                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
 927
 928         if (test_opt(sb, USRQUOTA))
 929                 seq_puts(seq, ",usrquota");
 930
 931         if (test_opt(sb, GRPQUOTA))
 932                 seq_puts(seq, ",grpquota");
 933 #endif
 934 }
 935
 936 /*
 937  * Show an option if
 938  *  - it's set to a non-default value OR
 939  *  - if the per-sb default is different from the global default
 940  */
 941 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
 942 {
 943         int def_errors;
 944         unsigned long def_mount_opts;
 945         struct super_block *sb = vfs->mnt_sb;
 946         struct ext4_sb_info *sbi = EXT4_SB(sb);
 947         struct ext4_super_block *es = sbi->s_es;
 948
 949         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
 950         def_errors     = le16_to_cpu(es->s_errors);
 951
 952         if (sbi->s_sb_block != 1)
 953                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
 954         if (test_opt(sb, MINIX_DF))
 955                 seq_puts(seq, ",minixdf");
 956         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
 957                 seq_puts(seq, ",grpid");
 958         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
 959                 seq_puts(seq, ",nogrpid");
 960         if (sbi->s_resuid != EXT4_DEF_RESUID ||
 961             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
 962                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
 963         }
 964         if (sbi->s_resgid != EXT4_DEF_RESGID ||
 965             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
 966                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
 967         }
 968         if (test_opt(sb, ERRORS_RO)) {
 969                 if (def_errors == EXT4_ERRORS_PANIC ||
 970                     def_errors == EXT4_ERRORS_CONTINUE) {
 971                         seq_puts(seq, ",errors=remount-ro");
 972                 }
 973         }
 974         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
 975                 seq_puts(seq, ",errors=continue");
 976         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
 977                 seq_puts(seq, ",errors=panic");
 978         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
 979                 seq_puts(seq, ",nouid32");
 980         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
 981                 seq_puts(seq, ",debug");
 982         if (test_opt(sb, OLDALLOC))
 983                 seq_puts(seq, ",oldalloc");
 984 #ifdef CONFIG_EXT4_FS_XATTR
 985         if (test_opt(sb, XATTR_USER) &&
 986                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
 987                 seq_puts(seq, ",user_xattr");
 988         if (!test_opt(sb, XATTR_USER) &&
 989             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
 990                 seq_puts(seq, ",nouser_xattr");
 991         }
 992 #endif
 993 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 994         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
 995                 seq_puts(seq, ",acl");
 996         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
 997                 seq_puts(seq, ",noacl");
 998 #endif
 999         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
1000                 seq_printf(seq, ",commit=%u",
1001                            (unsigned) (sbi->s_commit_interval / HZ));
1002         }
1003         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
1004                 seq_printf(seq, ",min_batch_time=%u",
1005                            (unsigned) sbi->s_min_batch_time);
1006         }
1007         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
1008                 seq_printf(seq, ",max_batch_time=%u",
1009                            (unsigned) sbi->s_min_batch_time);
1010         }
1011
1012         /*
1013          * We're changing the default of barrier mount option, so
1014          * let's always display its mount state so it's clear what its
1015          * status is.
1016          */
1017         seq_puts(seq, ",barrier=");
1018         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
1019         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
1020                 seq_puts(seq, ",journal_async_commit");
1021         else if (test_opt(sb, JOURNAL_CHECKSUM))
1022                 seq_puts(seq, ",journal_checksum");
1023         if (test_opt(sb, I_VERSION))
1024                 seq_puts(seq, ",i_version");
1025         if (!test_opt(sb, DELALLOC) &&
1026             !(def_mount_opts & EXT4_DEFM_NODELALLOC))
1027                 seq_puts(seq, ",nodelalloc");
1028
1029         if (sbi->s_stripe)
1030                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
1031         /*
1032          * journal mode get enabled in different ways
1033          * So just print the value even if we didn't specify it
1034          */
1035         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1036                 seq_puts(seq, ",data=journal");
1037         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1038                 seq_puts(seq, ",data=ordered");
1039         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1040                 seq_puts(seq, ",data=writeback");
1041
1042         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1043                 seq_printf(seq, ",inode_readahead_blks=%u",
1044                            sbi->s_inode_readahead_blks);
1045
1046         if (test_opt(sb, DATA_ERR_ABORT))
1047                 seq_puts(seq, ",data_err=abort");
1048
1049         if (test_opt(sb, NO_AUTO_DA_ALLOC))
1050                 seq_puts(seq, ",noauto_da_alloc");
1051
1052         if (test_opt(sb, DISCARD) && !(def_mount_opts & EXT4_DEFM_DISCARD))
1053                 seq_puts(seq, ",discard");
1054
1055         if (test_opt(sb, NOLOAD))
1056                 seq_puts(seq, ",norecovery");
1057
1058         if (test_opt(sb, DIOREAD_NOLOCK))
1059                 seq_puts(seq, ",dioread_nolock");
1060
1061         if (test_opt(sb, BLOCK_VALIDITY) &&
1062             !(def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY))
1063                 seq_puts(seq, ",block_validity");
1064
1065         if (!test_opt(sb, INIT_INODE_TABLE))
1066                 seq_puts(seq, ",noinit_inode_table");
1067         else if (sbi->s_li_wait_mult)
1068                 seq_printf(seq, ",init_inode_table=%u",
1069                            (unsigned) sbi->s_li_wait_mult);
1070
1071         ext4_show_quota_options(seq, sb);
1072
1073         return 0;
1074 }
1075
1076 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1077                                         u64 ino, u32 generation)
1078 {
1079         struct inode *inode;
1080
1081         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1082                 return ERR_PTR(-ESTALE);
1083         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1084                 return ERR_PTR(-ESTALE);
1085
1086         /* iget isn't really right if the inode is currently unallocated!!
1087          *
1088          * ext4_read_inode will return a bad_inode if the inode had been
1089          * deleted, so we should be safe.
1090          *
1091          * Currently we don't know the generation for parent directory, so
1092          * a generation of 0 means "accept any"
1093          */
1094         inode = ext4_iget(sb, ino);
1095         if (IS_ERR(inode))
1096                 return ERR_CAST(inode);
1097         if (generation && inode->i_generation != generation) {
1098                 iput(inode);
1099                 return ERR_PTR(-ESTALE);
1100         }
1101
1102         return inode;
1103 }
1104
1105 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1106                                         int fh_len, int fh_type)
1107 {
1108         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1109                                     ext4_nfs_get_inode);
1110 }
1111
1112 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1113                                         int fh_len, int fh_type)
1114 {
1115         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1116                                     ext4_nfs_get_inode);
1117 }
1118
1119 /*
1120  * Try to release metadata pages (indirect blocks, directories) which are
1121  * mapped via the block device.  Since these pages could have journal heads
1122  * which would prevent try_to_free_buffers() from freeing them, we must use
1123  * jbd2 layer's try_to_free_buffers() function to release them.
1124  */
1125 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1126                                  gfp_t wait)
1127 {
1128         journal_t *journal = EXT4_SB(sb)->s_journal;
1129
1130         WARN_ON(PageChecked(page));
1131         if (!page_has_buffers(page))
1132                 return 0;
1133         if (journal)
1134                 return jbd2_journal_try_to_free_buffers(journal, page,
1135                                                         wait & ~__GFP_WAIT);
1136         return try_to_free_buffers(page);
1137 }
1138
1139 #ifdef CONFIG_QUOTA
1140 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1141 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1142
1143 static int ext4_write_dquot(struct dquot *dquot);
1144 static int ext4_acquire_dquot(struct dquot *dquot);
1145 static int ext4_release_dquot(struct dquot *dquot);
1146 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1147 static int ext4_write_info(struct super_block *sb, int type);
1148 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1149                                 char *path);
1150 static int ext4_quota_off(struct super_block *sb, int type);
1151 static int ext4_quota_on_mount(struct super_block *sb, int type);
1152 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1153                                size_t len, loff_t off);
1154 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1155                                 const char *data, size_t len, loff_t off);
1156
1157 static const struct dquot_operations ext4_quota_operations = {
1158 #ifdef CONFIG_QUOTA
1159         .get_reserved_space = ext4_get_reserved_space,
1160 #endif
1161         .write_dquot    = ext4_write_dquot,
1162         .acquire_dquot  = ext4_acquire_dquot,
1163         .release_dquot  = ext4_release_dquot,
1164         .mark_dirty     = ext4_mark_dquot_dirty,
1165         .write_info     = ext4_write_info,
1166         .alloc_dquot    = dquot_alloc,
1167         .destroy_dquot  = dquot_destroy,
1168 };
1169
1170 static const struct quotactl_ops ext4_qctl_operations = {
1171         .quota_on       = ext4_quota_on,
1172         .quota_off      = ext4_quota_off,
1173         .quota_sync     = dquot_quota_sync,
1174         .get_info       = dquot_get_dqinfo,
1175         .set_info       = dquot_set_dqinfo,
1176         .get_dqblk      = dquot_get_dqblk,
1177         .set_dqblk      = dquot_set_dqblk
1178 };
1179 #endif
1180
1181 static const struct super_operations ext4_sops = {
1182         .alloc_inode    = ext4_alloc_inode,
1183         .destroy_inode  = ext4_destroy_inode,
1184         .write_inode    = ext4_write_inode,
1185         .dirty_inode    = ext4_dirty_inode,
1186         .drop_inode     = ext4_drop_inode,
1187         .evict_inode    = ext4_evict_inode,
1188         .put_super      = ext4_put_super,
1189         .sync_fs        = ext4_sync_fs,
1190         .freeze_fs      = ext4_freeze,
1191         .unfreeze_fs    = ext4_unfreeze,
1192         .statfs         = ext4_statfs,
1193         .remount_fs     = ext4_remount,
1194         .show_options   = ext4_show_options,
1195 #ifdef CONFIG_QUOTA
1196         .quota_read     = ext4_quota_read,
1197         .quota_write    = ext4_quota_write,
1198 #endif
1199         .bdev_try_to_free_page = bdev_try_to_free_page,
1200 };
1201
1202 static const struct super_operations ext4_nojournal_sops = {
1203         .alloc_inode    = ext4_alloc_inode,
1204         .destroy_inode  = ext4_destroy_inode,
1205         .write_inode    = ext4_write_inode,
1206         .dirty_inode    = ext4_dirty_inode,
1207         .drop_inode     = ext4_drop_inode,
1208         .evict_inode    = ext4_evict_inode,
1209         .write_super    = ext4_write_super,
1210         .put_super      = ext4_put_super,
1211         .statfs         = ext4_statfs,
1212         .remount_fs     = ext4_remount,
1213         .show_options   = ext4_show_options,
1214 #ifdef CONFIG_QUOTA
1215         .quota_read     = ext4_quota_read,
1216         .quota_write    = ext4_quota_write,
1217 #endif
1218         .bdev_try_to_free_page = bdev_try_to_free_page,
1219 };
1220
1221 static const struct export_operations ext4_export_ops = {
1222         .fh_to_dentry = ext4_fh_to_dentry,
1223         .fh_to_parent = ext4_fh_to_parent,
1224         .get_parent = ext4_get_parent,
1225 };
1226
1227 enum {
1228         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1229         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1230         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1231         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1232         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1233         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1234         Opt_journal_update, Opt_journal_dev,
1235         Opt_journal_checksum, Opt_journal_async_commit,
1236         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1237         Opt_data_err_abort, Opt_data_err_ignore,
1238         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1239         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1240         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1241         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1242         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1243         Opt_block_validity, Opt_noblock_validity,
1244         Opt_inode_readahead_blks, Opt_journal_ioprio,
1245         Opt_dioread_nolock, Opt_dioread_lock,
1246         Opt_discard, Opt_nodiscard,
1247         Opt_init_inode_table, Opt_noinit_inode_table,
1248 };
1249
1250 static const match_table_t tokens = {
1251         {Opt_bsd_df, "bsddf"},
1252         {Opt_minix_df, "minixdf"},
1253         {Opt_grpid, "grpid"},
1254         {Opt_grpid, "bsdgroups"},
1255         {Opt_nogrpid, "nogrpid"},
1256         {Opt_nogrpid, "sysvgroups"},
1257         {Opt_resgid, "resgid=%u"},
1258         {Opt_resuid, "resuid=%u"},
1259         {Opt_sb, "sb=%u"},
1260         {Opt_err_cont, "errors=continue"},
1261         {Opt_err_panic, "errors=panic"},
1262         {Opt_err_ro, "errors=remount-ro"},
1263         {Opt_nouid32, "nouid32"},
1264         {Opt_debug, "debug"},
1265         {Opt_oldalloc, "oldalloc"},
1266         {Opt_orlov, "orlov"},
1267         {Opt_user_xattr, "user_xattr"},
1268         {Opt_nouser_xattr, "nouser_xattr"},
1269         {Opt_acl, "acl"},
1270         {Opt_noacl, "noacl"},
1271         {Opt_noload, "noload"},
1272         {Opt_noload, "norecovery"},
1273         {Opt_nobh, "nobh"},
1274         {Opt_bh, "bh"},
1275         {Opt_commit, "commit=%u"},
1276         {Opt_min_batch_time, "min_batch_time=%u"},
1277         {Opt_max_batch_time, "max_batch_time=%u"},
1278         {Opt_journal_update, "journal=update"},
1279         {Opt_journal_dev, "journal_dev=%u"},
1280         {Opt_journal_checksum, "journal_checksum"},
1281         {Opt_journal_async_commit, "journal_async_commit"},
1282         {Opt_abort, "abort"},
1283         {Opt_data_journal, "data=journal"},
1284         {Opt_data_ordered, "data=ordered"},
1285         {Opt_data_writeback, "data=writeback"},
1286         {Opt_data_err_abort, "data_err=abort"},
1287         {Opt_data_err_ignore, "data_err=ignore"},
1288         {Opt_offusrjquota, "usrjquota="},
1289         {Opt_usrjquota, "usrjquota=%s"},
1290         {Opt_offgrpjquota, "grpjquota="},
1291         {Opt_grpjquota, "grpjquota=%s"},
1292         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1293         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1294         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1295         {Opt_grpquota, "grpquota"},
1296         {Opt_noquota, "noquota"},
1297         {Opt_quota, "quota"},
1298         {Opt_usrquota, "usrquota"},
1299         {Opt_barrier, "barrier=%u"},
1300         {Opt_barrier, "barrier"},
1301         {Opt_nobarrier, "nobarrier"},
1302         {Opt_i_version, "i_version"},
1303         {Opt_stripe, "stripe=%u"},
1304         {Opt_resize, "resize"},
1305         {Opt_delalloc, "delalloc"},
1306         {Opt_nodelalloc, "nodelalloc"},
1307         {Opt_block_validity, "block_validity"},
1308         {Opt_noblock_validity, "noblock_validity"},
1309         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1310         {Opt_journal_ioprio, "journal_ioprio=%u"},
1311         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1312         {Opt_auto_da_alloc, "auto_da_alloc"},
1313         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1314         {Opt_dioread_nolock, "dioread_nolock"},
1315         {Opt_dioread_lock, "dioread_lock"},
1316         {Opt_discard, "discard"},
1317         {Opt_nodiscard, "nodiscard"},
1318         {Opt_init_inode_table, "init_itable=%u"},
1319         {Opt_init_inode_table, "init_itable"},
1320         {Opt_noinit_inode_table, "noinit_itable"},
1321         {Opt_err, NULL},
1322 };
1323
1324 static ext4_fsblk_t get_sb_block(void **data)
1325 {
1326         ext4_fsblk_t    sb_block;
1327         char            *options = (char *) *data;
1328
1329         if (!options || strncmp(options, "sb=", 3) != 0)
1330                 return 1;       /* Default location */
1331
1332         options += 3;
1333         /* TODO: use simple_strtoll with >32bit ext4 */
1334         sb_block = simple_strtoul(options, &options, 0);
1335         if (*options && *options != ',') {
1336                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1337                        (char *) *data);
1338                 return 1;
1339         }
1340         if (*options == ',')
1341                 options++;
1342         *data = (void *) options;
1343
1344         return sb_block;
1345 }
1346
1347 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1348 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1349         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1350
1351 #ifdef CONFIG_QUOTA
1352 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1353 {
1354         struct ext4_sb_info *sbi = EXT4_SB(sb);
1355         char *qname;
1356
1357         if (sb_any_quota_loaded(sb) &&
1358                 !sbi->s_qf_names[qtype]) {
1359                 ext4_msg(sb, KERN_ERR,
1360                         "Cannot change journaled "
1361                         "quota options when quota turned on");
1362                 return 0;
1363         }
1364         qname = match_strdup(args);
1365         if (!qname) {
1366                 ext4_msg(sb, KERN_ERR,
1367                         "Not enough memory for storing quotafile name");
1368                 return 0;
1369         }
1370         if (sbi->s_qf_names[qtype] &&
1371                 strcmp(sbi->s_qf_names[qtype], qname)) {
1372                 ext4_msg(sb, KERN_ERR,
1373                         "%s quota file already specified", QTYPE2NAME(qtype));
1374                 kfree(qname);
1375                 return 0;
1376         }
1377         sbi->s_qf_names[qtype] = qname;
1378         if (strchr(sbi->s_qf_names[qtype], '/')) {
1379                 ext4_msg(sb, KERN_ERR,
1380                         "quotafile must be on filesystem root");
1381                 kfree(sbi->s_qf_names[qtype]);
1382                 sbi->s_qf_names[qtype] = NULL;
1383                 return 0;
1384         }
1385         set_opt(sbi->s_mount_opt, QUOTA);
1386         return 1;
1387 }
1388
1389 static int clear_qf_name(struct super_block *sb, int qtype)
1390 {
1391
1392         struct ext4_sb_info *sbi = EXT4_SB(sb);
1393
1394         if (sb_any_quota_loaded(sb) &&
1395                 sbi->s_qf_names[qtype]) {
1396                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1397                         " when quota turned on");
1398                 return 0;
1399         }
1400         /*
1401          * The space will be released later when all options are confirmed
1402          * to be correct
1403          */
1404         sbi->s_qf_names[qtype] = NULL;
1405         return 1;
1406 }
1407 #endif
1408
1409 static int parse_options(char *options, struct super_block *sb,
1410                          unsigned long *journal_devnum,
1411                          unsigned int *journal_ioprio,
1412                          ext4_fsblk_t *n_blocks_count, int is_remount)
1413 {
1414         struct ext4_sb_info *sbi = EXT4_SB(sb);
1415         char *p;
1416         substring_t args[MAX_OPT_ARGS];
1417         int data_opt = 0;
1418         int option;
1419 #ifdef CONFIG_QUOTA
1420         int qfmt;
1421 #endif
1422
1423         if (!options)
1424                 return 1;
1425
1426         while ((p = strsep(&options, ",")) != NULL) {
1427                 int token;
1428                 if (!*p)
1429                         continue;
1430
1431                 /*
1432                  * Initialize args struct so we know whether arg was
1433                  * found; some options take optional arguments.
1434                  */
1435                 args[0].to = args[0].from = 0;
1436                 token = match_token(p, tokens, args);
1437                 switch (token) {
1438                 case Opt_bsd_df:
1439                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1440                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1441                         break;
1442                 case Opt_minix_df:
1443                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1444                         set_opt(sbi->s_mount_opt, MINIX_DF);
1445
1446                         break;
1447                 case Opt_grpid:
1448                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1449                         set_opt(sbi->s_mount_opt, GRPID);
1450
1451                         break;
1452                 case Opt_nogrpid:
1453                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1454                         clear_opt(sbi->s_mount_opt, GRPID);
1455
1456                         break;
1457                 case Opt_resuid:
1458                         if (match_int(&args[0], &option))
1459                                 return 0;
1460                         sbi->s_resuid = option;
1461                         break;
1462                 case Opt_resgid:
1463                         if (match_int(&args[0], &option))
1464                                 return 0;
1465                         sbi->s_resgid = option;
1466                         break;
1467                 case Opt_sb:
1468                         /* handled by get_sb_block() instead of here */
1469                         /* *sb_block = match_int(&args[0]); */
1470                         break;
1471                 case Opt_err_panic:
1472                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1473                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1474                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1475                         break;
1476                 case Opt_err_ro:
1477                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1478                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1479                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1480                         break;
1481                 case Opt_err_cont:
1482                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1483                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1484                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1485                         break;
1486                 case Opt_nouid32:
1487                         set_opt(sbi->s_mount_opt, NO_UID32);
1488                         break;
1489                 case Opt_debug:
1490                         set_opt(sbi->s_mount_opt, DEBUG);
1491                         break;
1492                 case Opt_oldalloc:
1493                         set_opt(sbi->s_mount_opt, OLDALLOC);
1494                         break;
1495                 case Opt_orlov:
1496                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1497                         break;
1498 #ifdef CONFIG_EXT4_FS_XATTR
1499                 case Opt_user_xattr:
1500                         set_opt(sbi->s_mount_opt, XATTR_USER);
1501                         break;
1502                 case Opt_nouser_xattr:
1503                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1504                         break;
1505 #else
1506                 case Opt_user_xattr:
1507                 case Opt_nouser_xattr:
1508                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1509                         break;
1510 #endif
1511 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1512                 case Opt_acl:
1513                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1514                         break;
1515                 case Opt_noacl:
1516                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1517                         break;
1518 #else
1519                 case Opt_acl:
1520                 case Opt_noacl:
1521                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1522                         break;
1523 #endif
1524                 case Opt_journal_update:
1525                         /* @@@ FIXME */
1526                         /* Eventually we will want to be able to create
1527                            a journal file here.  For now, only allow the
1528                            user to specify an existing inode to be the
1529                            journal file. */
1530                         if (is_remount) {
1531                                 ext4_msg(sb, KERN_ERR,
1532                                          "Cannot specify journal on remount");
1533                                 return 0;
1534                         }
1535                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1536                         break;
1537                 case Opt_journal_dev:
1538                         if (is_remount) {
1539                                 ext4_msg(sb, KERN_ERR,
1540                                         "Cannot specify journal on remount");
1541                                 return 0;
1542                         }
1543                         if (match_int(&args[0], &option))
1544                                 return 0;
1545                         *journal_devnum = option;
1546                         break;
1547                 case Opt_journal_checksum:
1548                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1549                         break;
1550                 case Opt_journal_async_commit:
1551                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1552                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1553                         break;
1554                 case Opt_noload:
1555                         set_opt(sbi->s_mount_opt, NOLOAD);
1556                         break;
1557                 case Opt_commit:
1558                         if (match_int(&args[0], &option))
1559                                 return 0;
1560                         if (option < 0)
1561                                 return 0;
1562                         if (option == 0)
1563                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1564                         sbi->s_commit_interval = HZ * option;
1565                         break;
1566                 case Opt_max_batch_time:
1567                         if (match_int(&args[0], &option))
1568                                 return 0;
1569                         if (option < 0)
1570                                 return 0;
1571                         if (option == 0)
1572                                 option = EXT4_DEF_MAX_BATCH_TIME;
1573                         sbi->s_max_batch_time = option;
1574                         break;
1575                 case Opt_min_batch_time:
1576                         if (match_int(&args[0], &option))
1577                                 return 0;
1578                         if (option < 0)
1579                                 return 0;
1580                         sbi->s_min_batch_time = option;
1581                         break;
1582                 case Opt_data_journal:
1583                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1584                         goto datacheck;
1585                 case Opt_data_ordered:
1586                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1587                         goto datacheck;
1588                 case Opt_data_writeback:
1589                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1590                 datacheck:
1591                         if (is_remount) {
1592                                 if (test_opt(sb, DATA_FLAGS) != data_opt) {
1593                                         ext4_msg(sb, KERN_ERR,
1594                                                 "Cannot change data mode on remount");
1595                                         return 0;
1596                                 }
1597                         } else {
1598                                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
1599                                 sbi->s_mount_opt |= data_opt;
1600                         }
1601                         break;
1602                 case Opt_data_err_abort:
1603                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1604                         break;
1605                 case Opt_data_err_ignore:
1606                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1607                         break;
1608 #ifdef CONFIG_QUOTA
1609                 case Opt_usrjquota:
1610                         if (!set_qf_name(sb, USRQUOTA, &args[0]))
1611                                 return 0;
1612                         break;
1613                 case Opt_grpjquota:
1614                         if (!set_qf_name(sb, GRPQUOTA, &args[0]))
1615                                 return 0;
1616                         break;
1617                 case Opt_offusrjquota:
1618                         if (!clear_qf_name(sb, USRQUOTA))
1619                                 return 0;
1620                         break;
1621                 case Opt_offgrpjquota:
1622                         if (!clear_qf_name(sb, GRPQUOTA))
1623                                 return 0;
1624                         break;
1625
1626                 case Opt_jqfmt_vfsold:
1627                         qfmt = QFMT_VFS_OLD;
1628                         goto set_qf_format;
1629                 case Opt_jqfmt_vfsv0:
1630                         qfmt = QFMT_VFS_V0;
1631                         goto set_qf_format;
1632                 case Opt_jqfmt_vfsv1:
1633                         qfmt = QFMT_VFS_V1;
1634 set_qf_format:
1635                         if (sb_any_quota_loaded(sb) &&
1636                             sbi->s_jquota_fmt != qfmt) {
1637                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1638                                         "journaled quota options when "
1639                                         "quota turned on");
1640                                 return 0;
1641                         }
1642                         sbi->s_jquota_fmt = qfmt;
1643                         break;
1644                 case Opt_quota:
1645                 case Opt_usrquota:
1646                         set_opt(sbi->s_mount_opt, QUOTA);
1647                         set_opt(sbi->s_mount_opt, USRQUOTA);
1648                         break;
1649                 case Opt_grpquota:
1650                         set_opt(sbi->s_mount_opt, QUOTA);
1651                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1652                         break;
1653                 case Opt_noquota:
1654                         if (sb_any_quota_loaded(sb)) {
1655                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1656                                         "options when quota turned on");
1657                                 return 0;
1658                         }
1659                         clear_opt(sbi->s_mount_opt, QUOTA);
1660                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1661                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1662                         break;
1663 #else
1664                 case Opt_quota:
1665                 case Opt_usrquota:
1666                 case Opt_grpquota:
1667                         ext4_msg(sb, KERN_ERR,
1668                                 "quota options not supported");
1669                         break;
1670                 case Opt_usrjquota:
1671                 case Opt_grpjquota:
1672                 case Opt_offusrjquota:
1673                 case Opt_offgrpjquota:
1674                 case Opt_jqfmt_vfsold:
1675                 case Opt_jqfmt_vfsv0:
1676                 case Opt_jqfmt_vfsv1:
1677                         ext4_msg(sb, KERN_ERR,
1678                                 "journaled quota options not supported");
1679                         break;
1680                 case Opt_noquota:
1681                         break;
1682 #endif
1683                 case Opt_abort:
1684                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1685                         break;
1686                 case Opt_nobarrier:
1687                         clear_opt(sbi->s_mount_opt, BARRIER);
1688                         break;
1689                 case Opt_barrier:
1690                         if (args[0].from) {
1691                                 if (match_int(&args[0], &option))
1692                                         return 0;
1693                         } else
1694                                 option = 1;     /* No argument, default to 1 */
1695                         if (option)
1696                                 set_opt(sbi->s_mount_opt, BARRIER);
1697                         else
1698                                 clear_opt(sbi->s_mount_opt, BARRIER);
1699                         break;
1700                 case Opt_ignore:
1701                         break;
1702                 case Opt_resize:
1703                         if (!is_remount) {
1704                                 ext4_msg(sb, KERN_ERR,
1705                                         "resize option only available "
1706                                         "for remount");
1707                                 return 0;
1708                         }
1709                         if (match_int(&args[0], &option) != 0)
1710                                 return 0;
1711                         *n_blocks_count = option;
1712                         break;
1713                 case Opt_nobh:
1714                         ext4_msg(sb, KERN_WARNING,
1715                                  "Ignoring deprecated nobh option");
1716                         break;
1717                 case Opt_bh:
1718                         ext4_msg(sb, KERN_WARNING,
1719                                  "Ignoring deprecated bh option");
1720                         break;
1721                 case Opt_i_version:
1722                         set_opt(sbi->s_mount_opt, I_VERSION);
1723                         sb->s_flags |= MS_I_VERSION;
1724                         break;
1725                 case Opt_nodelalloc:
1726                         clear_opt(sbi->s_mount_opt, DELALLOC);
1727                         break;
1728                 case Opt_stripe:
1729                         if (match_int(&args[0], &option))
1730                                 return 0;
1731                         if (option < 0)
1732                                 return 0;
1733                         sbi->s_stripe = option;
1734                         break;
1735                 case Opt_delalloc:
1736                         set_opt(sbi->s_mount_opt, DELALLOC);
1737                         break;
1738                 case Opt_block_validity:
1739                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1740                         break;
1741                 case Opt_noblock_validity:
1742                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1743                         break;
1744                 case Opt_inode_readahead_blks:
1745                         if (match_int(&args[0], &option))
1746                                 return 0;
1747                         if (option < 0 || option > (1 << 30))
1748                                 return 0;
1749                         if (!is_power_of_2(option)) {
1750                                 ext4_msg(sb, KERN_ERR,
1751                                          "EXT4-fs: inode_readahead_blks"
1752                                          " must be a power of 2");
1753                                 return 0;
1754                         }
1755                         sbi->s_inode_readahead_blks = option;
1756                         break;
1757                 case Opt_journal_ioprio:
1758                         if (match_int(&args[0], &option))
1759                                 return 0;
1760                         if (option < 0 || option > 7)
1761                                 break;
1762                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1763                                                             option);
1764                         break;
1765                 case Opt_noauto_da_alloc:
1766                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1767                         break;
1768                 case Opt_auto_da_alloc:
1769                         if (args[0].from) {
1770                                 if (match_int(&args[0], &option))
1771                                         return 0;
1772                         } else
1773                                 option = 1;     /* No argument, default to 1 */
1774                         if (option)
1775                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1776                         else
1777                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1778                         break;
1779                 case Opt_discard:
1780                         set_opt(sbi->s_mount_opt, DISCARD);
1781                         break;
1782                 case Opt_nodiscard:
1783                         clear_opt(sbi->s_mount_opt, DISCARD);
1784                         break;
1785                 case Opt_dioread_nolock:
1786                         set_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
1787                         break;
1788                 case Opt_dioread_lock:
1789                         clear_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
1790                         break;
1791                 case Opt_init_inode_table:
1792                         set_opt(sbi->s_mount_opt, INIT_INODE_TABLE);
1793                         if (args[0].from) {
1794                                 if (match_int(&args[0], &option))
1795                                         return 0;
1796                         } else
1797                                 option = EXT4_DEF_LI_WAIT_MULT;
1798                         if (option < 0)
1799                                 return 0;
1800                         sbi->s_li_wait_mult = option;
1801                         break;
1802                 case Opt_noinit_inode_table:
1803                         clear_opt(sbi->s_mount_opt, INIT_INODE_TABLE);
1804                         break;
1805                 default:
1806                         ext4_msg(sb, KERN_ERR,
1807                                "Unrecognized mount option \"%s\" "
1808                                "or missing value", p);
1809                         return 0;
1810                 }
1811         }
1812 #ifdef CONFIG_QUOTA
1813         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1814                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1815                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1816
1817                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1818                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1819
1820                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1821                         ext4_msg(sb, KERN_ERR, "old and new quota "
1822                                         "format mixing");
1823                         return 0;
1824                 }
1825
1826                 if (!sbi->s_jquota_fmt) {
1827                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1828                                         "not specified");
1829                         return 0;
1830                 }
1831         } else {
1832                 if (sbi->s_jquota_fmt) {
1833                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1834                                         "specified with no journaling "
1835                                         "enabled");
1836                         return 0;
1837                 }
1838         }
1839 #endif
1840         return 1;
1841 }
1842
1843 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1844                             int read_only)
1845 {
1846         struct ext4_sb_info *sbi = EXT4_SB(sb);
1847         int res = 0;
1848
1849         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1850                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1851                          "forcing read-only mode");
1852                 res = MS_RDONLY;
1853         }
1854         if (read_only)
1855                 return res;
1856         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1857                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1858                          "running e2fsck is recommended");
1859         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1860                 ext4_msg(sb, KERN_WARNING,
1861                          "warning: mounting fs with errors, "
1862                          "running e2fsck is recommended");
1863         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1864                  le16_to_cpu(es->s_mnt_count) >=
1865                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1866                 ext4_msg(sb, KERN_WARNING,
1867                          "warning: maximal mount count reached, "
1868                          "running e2fsck is recommended");
1869         else if (le32_to_cpu(es->s_checkinterval) &&
1870                 (le32_to_cpu(es->s_lastcheck) +
1871                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1872                 ext4_msg(sb, KERN_WARNING,
1873                          "warning: checktime reached, "
1874                          "running e2fsck is recommended");
1875         if (!sbi->s_journal)
1876                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1877         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1878                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1879         le16_add_cpu(&es->s_mnt_count, 1);
1880         es->s_mtime = cpu_to_le32(get_seconds());
1881         ext4_update_dynamic_rev(sb);
1882         if (sbi->s_journal)
1883                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1884
1885         ext4_commit_super(sb, 1);
1886         if (test_opt(sb, DEBUG))
1887                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1888                                 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1889                         sb->s_blocksize,
1890                         sbi->s_groups_count,
1891                         EXT4_BLOCKS_PER_GROUP(sb),
1892                         EXT4_INODES_PER_GROUP(sb),
1893                         sbi->s_mount_opt);
1894
1895         return res;
1896 }
1897
1898 static int ext4_fill_flex_info(struct super_block *sb)
1899 {
1900         struct ext4_sb_info *sbi = EXT4_SB(sb);
1901         struct ext4_group_desc *gdp = NULL;
1902         ext4_group_t flex_group_count;
1903         ext4_group_t flex_group;
1904         int groups_per_flex = 0;
1905         size_t size;
1906         int i;
1907
1908         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1909         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1910
1911         if (groups_per_flex < 2) {
1912                 sbi->s_log_groups_per_flex = 0;
1913                 return 1;
1914         }
1915
1916         /* We allocate both existing and potentially added groups */
1917         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1918                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1919                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1920         size = flex_group_count * sizeof(struct flex_groups);
1921         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1922         if (sbi->s_flex_groups == NULL) {
1923                 sbi->s_flex_groups = vmalloc(size);
1924                 if (sbi->s_flex_groups)
1925                         memset(sbi->s_flex_groups, 0, size);
1926         }
1927         if (sbi->s_flex_groups == NULL) {
1928                 ext4_msg(sb, KERN_ERR, "not enough memory for "
1929                                 "%u flex groups", flex_group_count);
1930                 goto failed;
1931         }
1932
1933         for (i = 0; i < sbi->s_groups_count; i++) {
1934                 gdp = ext4_get_group_desc(sb, i, NULL);
1935
1936                 flex_group = ext4_flex_group(sbi, i);
1937                 atomic_add(ext4_free_inodes_count(sb, gdp),
1938                            &sbi->s_flex_groups[flex_group].free_inodes);
1939                 atomic_add(ext4_free_blks_count(sb, gdp),
1940                            &sbi->s_flex_groups[flex_group].free_blocks);
1941                 atomic_add(ext4_used_dirs_count(sb, gdp),
1942                            &sbi->s_flex_groups[flex_group].used_dirs);
1943         }
1944
1945         return 1;
1946 failed:
1947         return 0;
1948 }
1949
1950 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1951                             struct ext4_group_desc *gdp)
1952 {
1953         __u16 crc = 0;
1954
1955         if (sbi->s_es->s_feature_ro_compat &
1956             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1957                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1958                 __le32 le_group = cpu_to_le32(block_group);
1959
1960                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1961                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1962                 crc = crc16(crc, (__u8 *)gdp, offset);
1963                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1964                 /* for checksum of struct ext4_group_desc do the rest...*/
1965                 if ((sbi->s_es->s_feature_incompat &
1966                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1967                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1968                         crc = crc16(crc, (__u8 *)gdp + offset,
1969                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1970                                         offset);
1971         }
1972
1973         return cpu_to_le16(crc);
1974 }
1975
1976 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1977                                 struct ext4_group_desc *gdp)
1978 {
1979         if ((sbi->s_es->s_feature_ro_compat &
1980              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1981             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1982                 return 0;
1983
1984         return 1;
1985 }
1986
1987 /* Called at mount-time, super-block is locked */
1988 static int ext4_check_descriptors(struct super_block *sb,
1989                                   ext4_group_t *first_not_zeroed)
1990 {
1991         struct ext4_sb_info *sbi = EXT4_SB(sb);
1992         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1993         ext4_fsblk_t last_block;
1994         ext4_fsblk_t block_bitmap;
1995         ext4_fsblk_t inode_bitmap;
1996         ext4_fsblk_t inode_table;
1997         int flexbg_flag = 0;
1998         ext4_group_t i, grp = sbi->s_groups_count;
1999
2000         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2001                 flexbg_flag = 1;
2002
2003         ext4_debug("Checking group descriptors");
2004
2005         for (i = 0; i < sbi->s_groups_count; i++) {
2006                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2007
2008                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2009                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2010                 else
2011                         last_block = first_block +
2012                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2013
2014                 if ((grp == sbi->s_groups_count) &&
2015                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2016                         grp = i;
2017
2018                 block_bitmap = ext4_block_bitmap(sb, gdp);
2019                 if (block_bitmap < first_block || block_bitmap > last_block) {
2020                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2021                                "Block bitmap for group %u not in group "
2022                                "(block %llu)!", i, block_bitmap);
2023                         return 0;
2024                 }
2025                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2026                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2027                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2028                                "Inode bitmap for group %u not in group "
2029                                "(block %llu)!", i, inode_bitmap);
2030                         return 0;
2031                 }
2032                 inode_table = ext4_inode_table(sb, gdp);
2033                 if (inode_table < first_block ||
2034                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2035                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2036                                "Inode table for group %u not in group "
2037                                "(block %llu)!", i, inode_table);
2038                         return 0;
2039                 }
2040                 ext4_lock_group(sb, i);
2041                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
2042                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2043                                  "Checksum for group %u failed (%u!=%u)",
2044                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2045                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2046                         if (!(sb->s_flags & MS_RDONLY)) {
2047                                 ext4_unlock_group(sb, i);
2048                                 return 0;
2049                         }
2050                 }
2051                 ext4_unlock_group(sb, i);
2052                 if (!flexbg_flag)
2053                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2054         }
2055         if (NULL != first_not_zeroed)
2056                 *first_not_zeroed = grp;
2057
2058         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
2059         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2060         return 1;
2061 }
2062
2063 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2064  * the superblock) which were deleted from all directories, but held open by
2065  * a process at the time of a crash.  We walk the list and try to delete these
2066  * inodes at recovery time (only with a read-write filesystem).
2067  *
2068  * In order to keep the orphan inode chain consistent during traversal (in
2069  * case of crash during recovery), we link each inode into the superblock
2070  * orphan list_head and handle it the same way as an inode deletion during
2071  * normal operation (which journals the operations for us).
2072  *
2073  * We only do an iget() and an iput() on each inode, which is very safe if we
2074  * accidentally point at an in-use or already deleted inode.  The worst that
2075  * can happen in this case is that we get a "bit already cleared" message from
2076  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2077  * e2fsck was run on this filesystem, and it must have already done the orphan
2078  * inode cleanup for us, so we can safely abort without any further action.
2079  */
2080 static void ext4_orphan_cleanup(struct super_block *sb,
2081                                 struct ext4_super_block *es)
2082 {
2083         unsigned int s_flags = sb->s_flags;
2084         int nr_orphans = 0, nr_truncates = 0;
2085 #ifdef CONFIG_QUOTA
2086         int i;
2087 #endif
2088         if (!es->s_last_orphan) {
2089                 jbd_debug(4, "no orphan inodes to clean up\n");
2090                 return;
2091         }
2092
2093         if (bdev_read_only(sb->s_bdev)) {
2094                 ext4_msg(sb, KERN_ERR, "write access "
2095                         "unavailable, skipping orphan cleanup");
2096                 return;
2097         }
2098
2099         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2100                 if (es->s_last_orphan)
2101                         jbd_debug(1, "Errors on filesystem, "
2102                                   "clearing orphan list.\n");
2103                 es->s_last_orphan = 0;
2104                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2105                 return;
2106         }
2107
2108         if (s_flags & MS_RDONLY) {
2109                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2110                 sb->s_flags &= ~MS_RDONLY;
2111         }
2112 #ifdef CONFIG_QUOTA
2113         /* Needed for iput() to work correctly and not trash data */
2114         sb->s_flags |= MS_ACTIVE;
2115         /* Turn on quotas so that they are updated correctly */
2116         for (i = 0; i < MAXQUOTAS; i++) {
2117                 if (EXT4_SB(sb)->s_qf_names[i]) {
2118                         int ret = ext4_quota_on_mount(sb, i);
2119                         if (ret < 0)
2120                                 ext4_msg(sb, KERN_ERR,
2121                                         "Cannot turn on journaled "
2122                                         "quota: error %d", ret);
2123                 }
2124         }
2125 #endif
2126
2127         while (es->s_last_orphan) {
2128                 struct inode *inode;
2129
2130                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2131                 if (IS_ERR(inode)) {
2132                         es->s_last_orphan = 0;
2133                         break;
2134                 }
2135
2136                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2137                 dquot_initialize(inode);
2138                 if (inode->i_nlink) {
2139                         ext4_msg(sb, KERN_DEBUG,
2140                                 "%s: truncating inode %lu to %lld bytes",
2141                                 __func__, inode->i_ino, inode->i_size);
2142                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2143                                   inode->i_ino, inode->i_size);
2144                         ext4_truncate(inode);
2145                         nr_truncates++;
2146                 } else {
2147                         ext4_msg(sb, KERN_DEBUG,
2148                                 "%s: deleting unreferenced inode %lu",
2149                                 __func__, inode->i_ino);
2150                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2151                                   inode->i_ino);
2152                         nr_orphans++;
2153                 }
2154                 iput(inode);  /* The delete magic happens here! */
2155         }
2156
2157 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2158
2159         if (nr_orphans)
2160                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2161                        PLURAL(nr_orphans));
2162         if (nr_truncates)
2163                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2164                        PLURAL(nr_truncates));
2165 #ifdef CONFIG_QUOTA
2166         /* Turn quotas off */
2167         for (i = 0; i < MAXQUOTAS; i++) {
2168                 if (sb_dqopt(sb)->files[i])
2169                         dquot_quota_off(sb, i);
2170         }
2171 #endif
2172         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2173 }
2174
2175 /*
2176  * Maximal extent format file size.
2177  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2178  * extent format containers, within a sector_t, and within i_blocks
2179  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2180  * so that won't be a limiting factor.
2181  *
2182  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2183  */
2184 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2185 {
2186         loff_t res;
2187         loff_t upper_limit = MAX_LFS_FILESIZE;
2188
2189         /* small i_blocks in vfs inode? */
2190         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2191                 /*
2192                  * CONFIG_LBDAF is not enabled implies the inode
2193                  * i_block represent total blocks in 512 bytes
2194                  * 32 == size of vfs inode i_blocks * 8
2195                  */
2196                 upper_limit = (1LL << 32) - 1;
2197
2198                 /* total blocks in file system block size */
2199                 upper_limit >>= (blkbits - 9);
2200                 upper_limit <<= blkbits;
2201         }
2202
2203         /* 32-bit extent-start container, ee_block */
2204         res = 1LL << 32;
2205         res <<= blkbits;
2206         res -= 1;
2207
2208         /* Sanity check against vm- & vfs- imposed limits */
2209         if (res > upper_limit)
2210                 res = upper_limit;
2211
2212         return res;
2213 }
2214
2215 /*
2216  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2217  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2218  * We need to be 1 filesystem block less than the 2^48 sector limit.
2219  */
2220 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2221 {
2222         loff_t res = EXT4_NDIR_BLOCKS;
2223         int meta_blocks;
2224         loff_t upper_limit;
2225         /* This is calculated to be the largest file size for a dense, block
2226          * mapped file such that the file's total number of 512-byte sectors,
2227          * including data and all indirect blocks, does not exceed (2^48 - 1).
2228          *
2229          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2230          * number of 512-byte sectors of the file.
2231          */
2232
2233         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2234                 /*
2235                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2236                  * the inode i_block field represents total file blocks in
2237                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2238                  */
2239                 upper_limit = (1LL << 32) - 1;
2240
2241                 /* total blocks in file system block size */
2242                 upper_limit >>= (bits - 9);
2243
2244         } else {
2245                 /*
2246                  * We use 48 bit ext4_inode i_blocks
2247                  * With EXT4_HUGE_FILE_FL set the i_blocks
2248                  * represent total number of blocks in
2249                  * file system block size
2250                  */
2251                 upper_limit = (1LL << 48) - 1;
2252
2253         }
2254
2255         /* indirect blocks */
2256         meta_blocks = 1;
2257         /* double indirect blocks */
2258         meta_blocks += 1 + (1LL << (bits-2));
2259         /* tripple indirect blocks */
2260         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2261
2262         upper_limit -= meta_blocks;
2263         upper_limit <<= bits;
2264
2265         res += 1LL << (bits-2);
2266         res += 1LL << (2*(bits-2));
2267         res += 1LL << (3*(bits-2));
2268         res <<= bits;
2269         if (res > upper_limit)
2270                 res = upper_limit;
2271
2272         if (res > MAX_LFS_FILESIZE)
2273                 res = MAX_LFS_FILESIZE;
2274
2275         return res;
2276 }
2277
2278 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2279                                    ext4_fsblk_t logical_sb_block, int nr)
2280 {
2281         struct ext4_sb_info *sbi = EXT4_SB(sb);
2282         ext4_group_t bg, first_meta_bg;
2283         int has_super = 0;
2284
2285         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2286
2287         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2288             nr < first_meta_bg)
2289                 return logical_sb_block + nr + 1;
2290         bg = sbi->s_desc_per_block * nr;
2291         if (ext4_bg_has_super(sb, bg))
2292                 has_super = 1;
2293
2294         return (has_super + ext4_group_first_block_no(sb, bg));
2295 }
2296
2297 /**
2298  * ext4_get_stripe_size: Get the stripe size.
2299  * @sbi: In memory super block info
2300  *
2301  * If we have specified it via mount option, then
2302  * use the mount option value. If the value specified at mount time is
2303  * greater than the blocks per group use the super block value.
2304  * If the super block value is greater than blocks per group return 0.
2305  * Allocator needs it be less than blocks per group.
2306  *
2307  */
2308 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2309 {
2310         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2311         unsigned long stripe_width =
2312                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2313
2314         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2315                 return sbi->s_stripe;
2316
2317         if (stripe_width <= sbi->s_blocks_per_group)
2318                 return stripe_width;
2319
2320         if (stride <= sbi->s_blocks_per_group)
2321                 return stride;
2322
2323         return 0;
2324 }
2325
2326 /* sysfs supprt */
2327
2328 struct ext4_attr {
2329         struct attribute attr;
2330         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2331         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2332                          const char *, size_t);
2333         int offset;
2334 };
2335
2336 static int parse_strtoul(const char *buf,
2337                 unsigned long max, unsigned long *value)
2338 {
2339         char *endp;
2340
2341         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2342         endp = skip_spaces(endp);
2343         if (*endp || *value > max)
2344                 return -EINVAL;
2345
2346         return 0;
2347 }
2348
2349 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2350                                               struct ext4_sb_info *sbi,
2351                                               char *buf)
2352 {
2353         return snprintf(buf, PAGE_SIZE, "%llu\n",
2354                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2355 }
2356
2357 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2358                                          struct ext4_sb_info *sbi, char *buf)
2359 {
2360         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2361
2362         if (!sb->s_bdev->bd_part)
2363                 return snprintf(buf, PAGE_SIZE, "0\n");
2364         return snprintf(buf, PAGE_SIZE, "%lu\n",
2365                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2366                          sbi->s_sectors_written_start) >> 1);
2367 }
2368
2369 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2370                                           struct ext4_sb_info *sbi, char *buf)
2371 {
2372         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2373
2374         if (!sb->s_bdev->bd_part)
2375                 return snprintf(buf, PAGE_SIZE, "0\n");
2376         return snprintf(buf, PAGE_SIZE, "%llu\n",
2377                         (unsigned long long)(sbi->s_kbytes_written +
2378                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2379                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2380 }
2381
2382 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2383                                           struct ext4_sb_info *sbi,
2384                                           const char *buf, size_t count)
2385 {
2386         unsigned long t;
2387
2388         if (parse_strtoul(buf, 0x40000000, &t))
2389                 return -EINVAL;
2390
2391         if (!is_power_of_2(t))
2392                 return -EINVAL;
2393
2394         sbi->s_inode_readahead_blks = t;
2395         return count;
2396 }
2397
2398 static ssize_t sbi_ui_show(struct ext4_attr *a,
2399                            struct ext4_sb_info *sbi, char *buf)
2400 {
2401         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2402
2403         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2404 }
2405
2406 static ssize_t sbi_ui_store(struct ext4_attr *a,
2407                             struct ext4_sb_info *sbi,
2408                             const char *buf, size_t count)
2409 {
2410         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2411         unsigned long t;
2412
2413         if (parse_strtoul(buf, 0xffffffff, &t))
2414                 return -EINVAL;
2415         *ui = t;
2416         return count;
2417 }
2418
2419 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2420 static struct ext4_attr ext4_attr_##_name = {                   \
2421         .attr = {.name = __stringify(_name), .mode = _mode },   \
2422         .show   = _show,                                        \
2423         .store  = _store,                                       \
2424         .offset = offsetof(struct ext4_sb_info, _elname),       \
2425 }
2426 #define EXT4_ATTR(name, mode, show, store) \
2427 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2428
2429 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2430 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2431 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2432 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2433         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2434 #define ATTR_LIST(name) &ext4_attr_##name.attr
2435
2436 EXT4_RO_ATTR(delayed_allocation_blocks);
2437 EXT4_RO_ATTR(session_write_kbytes);
2438 EXT4_RO_ATTR(lifetime_write_kbytes);
2439 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2440                  inode_readahead_blks_store, s_inode_readahead_blks);
2441 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2442 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2443 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2444 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2445 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2446 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2447 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2448 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2449
2450 static struct attribute *ext4_attrs[] = {
2451         ATTR_LIST(delayed_allocation_blocks),
2452         ATTR_LIST(session_write_kbytes),
2453         ATTR_LIST(lifetime_write_kbytes),
2454         ATTR_LIST(inode_readahead_blks),
2455         ATTR_LIST(inode_goal),
2456         ATTR_LIST(mb_stats),
2457         ATTR_LIST(mb_max_to_scan),
2458         ATTR_LIST(mb_min_to_scan),
2459         ATTR_LIST(mb_order2_req),
2460         ATTR_LIST(mb_stream_req),
2461         ATTR_LIST(mb_group_prealloc),
2462         ATTR_LIST(max_writeback_mb_bump),
2463         NULL,
2464 };
2465
2466 /* Features this copy of ext4 supports */
2467 EXT4_INFO_ATTR(lazy_itable_init);
2468 EXT4_INFO_ATTR(batched_discard);
2469
2470 static struct attribute *ext4_feat_attrs[] = {
2471         ATTR_LIST(lazy_itable_init),
2472         ATTR_LIST(batched_discard),
2473         NULL,
2474 };
2475
2476 static ssize_t ext4_attr_show(struct kobject *kobj,
2477                               struct attribute *attr, char *buf)
2478 {
2479         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2480                                                 s_kobj);
2481         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2482
2483         return a->show ? a->show(a, sbi, buf) : 0;
2484 }
2485
2486 static ssize_t ext4_attr_store(struct kobject *kobj,
2487                                struct attribute *attr,
2488                                const char *buf, size_t len)
2489 {
2490         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2491                                                 s_kobj);
2492         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2493
2494         return a->store ? a->store(a, sbi, buf, len) : 0;
2495 }
2496
2497 static void ext4_sb_release(struct kobject *kobj)
2498 {
2499         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2500                                                 s_kobj);
2501         complete(&sbi->s_kobj_unregister);
2502 }
2503
2504 static const struct sysfs_ops ext4_attr_ops = {
2505         .show   = ext4_attr_show,
2506         .store  = ext4_attr_store,
2507 };
2508
2509 static struct kobj_type ext4_ktype = {
2510         .default_attrs  = ext4_attrs,
2511         .sysfs_ops      = &ext4_attr_ops,
2512         .release        = ext4_sb_release,
2513 };
2514
2515 static void ext4_feat_release(struct kobject *kobj)
2516 {
2517         complete(&ext4_feat->f_kobj_unregister);
2518 }
2519
2520 static struct kobj_type ext4_feat_ktype = {
2521         .default_attrs  = ext4_feat_attrs,
2522         .sysfs_ops      = &ext4_attr_ops,
2523         .release        = ext4_feat_release,
2524 };
2525
2526 /*
2527  * Check whether this filesystem can be mounted based on
2528  * the features present and the RDONLY/RDWR mount requested.
2529  * Returns 1 if this filesystem can be mounted as requested,
2530  * 0 if it cannot be.
2531  */
2532 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2533 {
2534         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2535                 ext4_msg(sb, KERN_ERR,
2536                         "Couldn't mount because of "
2537                         "unsupported optional features (%x)",
2538                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2539                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2540                 return 0;
2541         }
2542
2543         if (readonly)
2544                 return 1;
2545
2546         /* Check that feature set is OK for a read-write mount */
2547         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2548                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2549                          "unsupported optional features (%x)",
2550                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2551                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2552                 return 0;
2553         }
2554         /*
2555          * Large file size enabled file system can only be mounted
2556          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2557          */
2558         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2559                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2560                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2561                                  "cannot be mounted RDWR without "
2562                                  "CONFIG_LBDAF");
2563                         return 0;
2564                 }
2565         }
2566         return 1;
2567 }
2568
2569 /*
2570  * This function is called once a day if we have errors logged
2571  * on the file system
2572  */
2573 static void print_daily_error_info(unsigned long arg)
2574 {
2575         struct super_block *sb = (struct super_block *) arg;
2576         struct ext4_sb_info *sbi;
2577         struct ext4_super_block *es;
2578
2579         sbi = EXT4_SB(sb);
2580         es = sbi->s_es;
2581
2582         if (es->s_error_count)
2583                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2584                          le32_to_cpu(es->s_error_count));
2585         if (es->s_first_error_time) {
2586                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2587                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2588                        (int) sizeof(es->s_first_error_func),
2589                        es->s_first_error_func,
2590                        le32_to_cpu(es->s_first_error_line));
2591                 if (es->s_first_error_ino)
2592                         printk(": inode %u",
2593                                le32_to_cpu(es->s_first_error_ino));
2594                 if (es->s_first_error_block)
2595                         printk(": block %llu", (unsigned long long)
2596                                le64_to_cpu(es->s_first_error_block));
2597                 printk("\n");
2598         }
2599         if (es->s_last_error_time) {
2600                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2601                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2602                        (int) sizeof(es->s_last_error_func),
2603                        es->s_last_error_func,
2604                        le32_to_cpu(es->s_last_error_line));
2605                 if (es->s_last_error_ino)
2606                         printk(": inode %u",
2607                                le32_to_cpu(es->s_last_error_ino));
2608                 if (es->s_last_error_block)
2609                         printk(": block %llu", (unsigned long long)
2610                                le64_to_cpu(es->s_last_error_block));
2611                 printk("\n");
2612         }
2613         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2614 }
2615
2616 static void ext4_lazyinode_timeout(unsigned long data)
2617 {
2618         struct task_struct *p = (struct task_struct *)data;
2619         wake_up_process(p);
2620 }
2621
2622 /* Find next suitable group and run ext4_init_inode_table */
2623 static int ext4_run_li_request(struct ext4_li_request *elr)
2624 {
2625         struct ext4_group_desc *gdp = NULL;
2626         ext4_group_t group, ngroups;
2627         struct super_block *sb;
2628         unsigned long timeout = 0;
2629         int ret = 0;
2630
2631         sb = elr->lr_super;
2632         ngroups = EXT4_SB(sb)->s_groups_count;
2633
2634         for (group = elr->lr_next_group; group < ngroups; group++) {
2635                 gdp = ext4_get_group_desc(sb, group, NULL);
2636                 if (!gdp) {
2637                         ret = 1;
2638                         break;
2639                 }
2640
2641                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2642                         break;
2643         }
2644
2645         if (group == ngroups)
2646                 ret = 1;
2647
2648         if (!ret) {
2649                 timeout = jiffies;
2650                 ret = ext4_init_inode_table(sb, group,
2651                                             elr->lr_timeout ? 0 : 1);
2652                 if (elr->lr_timeout == 0) {
2653                         timeout = jiffies - timeout;
2654                         if (elr->lr_sbi->s_li_wait_mult)
2655                                 timeout *= elr->lr_sbi->s_li_wait_mult;
2656                         else
2657                                 timeout *= 20;
2658                         elr->lr_timeout = timeout;
2659                 }
2660                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2661                 elr->lr_next_group = group + 1;
2662         }
2663
2664         return ret;
2665 }
2666
2667 /*
2668  * Remove lr_request from the list_request and free the
2669  * request tructure. Should be called with li_list_mtx held
2670  */
2671 static void ext4_remove_li_request(struct ext4_li_request *elr)
2672 {
2673         struct ext4_sb_info *sbi;
2674
2675         if (!elr)
2676                 return;
2677
2678         sbi = elr->lr_sbi;
2679
2680         list_del(&elr->lr_request);
2681         sbi->s_li_request = NULL;
2682         kfree(elr);
2683 }
2684
2685 static void ext4_unregister_li_request(struct super_block *sb)
2686 {
2687         struct ext4_li_request *elr = EXT4_SB(sb)->s_li_request;
2688
2689         if (!ext4_li_info)
2690                 return;
2691
2692         mutex_lock(&ext4_li_info->li_list_mtx);
2693         ext4_remove_li_request(elr);
2694         mutex_unlock(&ext4_li_info->li_list_mtx);
2695 }
2696
2697 /*
2698  * This is the function where ext4lazyinit thread lives. It walks
2699  * through the request list searching for next scheduled filesystem.
2700  * When such a fs is found, run the lazy initialization request
2701  * (ext4_rn_li_request) and keep track of the time spend in this
2702  * function. Based on that time we compute next schedule time of
2703  * the request. When walking through the list is complete, compute
2704  * next waking time and put itself into sleep.
2705  */
2706 static int ext4_lazyinit_thread(void *arg)
2707 {
2708         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2709         struct list_head *pos, *n;
2710         struct ext4_li_request *elr;
2711         unsigned long next_wakeup;
2712         DEFINE_WAIT(wait);
2713
2714         BUG_ON(NULL == eli);
2715
2716         eli->li_timer.data = (unsigned long)current;
2717         eli->li_timer.function = ext4_lazyinode_timeout;
2718
2719         eli->li_task = current;
2720         wake_up(&eli->li_wait_task);
2721
2722 cont_thread:
2723         while (true) {
2724                 next_wakeup = MAX_JIFFY_OFFSET;
2725
2726                 mutex_lock(&eli->li_list_mtx);
2727                 if (list_empty(&eli->li_request_list)) {
2728                         mutex_unlock(&eli->li_list_mtx);
2729                         goto exit_thread;
2730                 }
2731
2732                 list_for_each_safe(pos, n, &eli->li_request_list) {
2733                         elr = list_entry(pos, struct ext4_li_request,
2734                                          lr_request);
2735
2736                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2737                                 if (ext4_run_li_request(elr) != 0) {
2738                                         /* error, remove the lazy_init job */
2739                                         ext4_remove_li_request(elr);
2740                                         continue;
2741                                 }
2742                         }
2743
2744                         if (time_before(elr->lr_next_sched, next_wakeup))
2745                                 next_wakeup = elr->lr_next_sched;
2746                 }
2747                 mutex_unlock(&eli->li_list_mtx);
2748
2749                 if (freezing(current))
2750                         refrigerator();
2751
2752                 if ((time_after_eq(jiffies, next_wakeup)) ||
2753                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2754                         cond_resched();
2755                         continue;
2756                 }
2757
2758                 eli->li_timer.expires = next_wakeup;
2759                 add_timer(&eli->li_timer);
2760                 prepare_to_wait(&eli->li_wait_daemon, &wait,
2761                                 TASK_INTERRUPTIBLE);
2762                 if (time_before(jiffies, next_wakeup))
2763                         schedule();
2764                 finish_wait(&eli->li_wait_daemon, &wait);
2765         }
2766
2767 exit_thread:
2768         /*
2769          * It looks like the request list is empty, but we need
2770          * to check it under the li_list_mtx lock, to prevent any
2771          * additions into it, and of course we should lock ext4_li_mtx
2772          * to atomically free the list and ext4_li_info, because at
2773          * this point another ext4 filesystem could be registering
2774          * new one.
2775          */
2776         mutex_lock(&ext4_li_mtx);
2777         mutex_lock(&eli->li_list_mtx);
2778         if (!list_empty(&eli->li_request_list)) {
2779                 mutex_unlock(&eli->li_list_mtx);
2780                 mutex_unlock(&ext4_li_mtx);
2781                 goto cont_thread;
2782         }
2783         mutex_unlock(&eli->li_list_mtx);
2784         del_timer_sync(&ext4_li_info->li_timer);
2785         eli->li_task = NULL;
2786         wake_up(&eli->li_wait_task);
2787
2788         kfree(ext4_li_info);
2789         ext4_li_info = NULL;
2790         mutex_unlock(&ext4_li_mtx);
2791
2792         return 0;
2793 }
2794
2795 static void ext4_clear_request_list(void)
2796 {
2797         struct list_head *pos, *n;
2798         struct ext4_li_request *elr;
2799
2800         mutex_lock(&ext4_li_info->li_list_mtx);
2801         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2802                 elr = list_entry(pos, struct ext4_li_request,
2803                                  lr_request);
2804                 ext4_remove_li_request(elr);
2805         }
2806         mutex_unlock(&ext4_li_info->li_list_mtx);
2807 }
2808
2809 static int ext4_run_lazyinit_thread(void)
2810 {
2811         struct task_struct *t;
2812
2813         t = kthread_run(ext4_lazyinit_thread, ext4_li_info, "ext4lazyinit");
2814         if (IS_ERR(t)) {
2815                 int err = PTR_ERR(t);
2816                 ext4_clear_request_list();
2817                 del_timer_sync(&ext4_li_info->li_timer);
2818                 kfree(ext4_li_info);
2819                 ext4_li_info = NULL;
2820                 printk(KERN_CRIT "EXT4: error %d creating inode table "
2821                                  "initialization thread\n",
2822                                  err);
2823                 return err;
2824         }
2825         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2826
2827         wait_event(ext4_li_info->li_wait_task, ext4_li_info->li_task != NULL);
2828         return 0;
2829 }
2830
2831 /*
2832  * Check whether it make sense to run itable init. thread or not.
2833  * If there is at least one uninitialized inode table, return
2834  * corresponding group number, else the loop goes through all
2835  * groups and return total number of groups.
2836  */
2837 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2838 {
2839         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2840         struct ext4_group_desc *gdp = NULL;
2841
2842         for (group = 0; group < ngroups; group++) {
2843                 gdp = ext4_get_group_desc(sb, group, NULL);
2844                 if (!gdp)
2845                         continue;
2846
2847                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2848                         break;
2849         }
2850
2851         return group;
2852 }
2853
2854 static int ext4_li_info_new(void)
2855 {
2856         struct ext4_lazy_init *eli = NULL;
2857
2858         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2859         if (!eli)
2860                 return -ENOMEM;
2861
2862         eli->li_task = NULL;
2863         INIT_LIST_HEAD(&eli->li_request_list);
2864         mutex_init(&eli->li_list_mtx);
2865
2866         init_waitqueue_head(&eli->li_wait_daemon);
2867         init_waitqueue_head(&eli->li_wait_task);
2868         init_timer(&eli->li_timer);
2869         eli->li_state |= EXT4_LAZYINIT_QUIT;
2870
2871         ext4_li_info = eli;
2872
2873         return 0;
2874 }
2875
2876 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2877                                             ext4_group_t start)
2878 {
2879         struct ext4_sb_info *sbi = EXT4_SB(sb);
2880         struct ext4_li_request *elr;
2881         unsigned long rnd;
2882
2883         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2884         if (!elr)
2885                 return NULL;
2886
2887         elr->lr_super = sb;
2888         elr->lr_sbi = sbi;
2889         elr->lr_next_group = start;
2890
2891         /*
2892          * Randomize first schedule time of the request to
2893          * spread the inode table initialization requests
2894          * better.
2895          */
2896         get_random_bytes(&rnd, sizeof(rnd));
2897         elr->lr_next_sched = jiffies + (unsigned long)rnd %
2898                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
2899
2900         return elr;
2901 }
2902
2903 static int ext4_register_li_request(struct super_block *sb,
2904                                     ext4_group_t first_not_zeroed)
2905 {
2906         struct ext4_sb_info *sbi = EXT4_SB(sb);
2907         struct ext4_li_request *elr;
2908         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2909         int ret;
2910
2911         if (sbi->s_li_request != NULL)
2912                 return 0;
2913
2914         if (first_not_zeroed == ngroups ||
2915             (sb->s_flags & MS_RDONLY) ||
2916             !test_opt(sb, INIT_INODE_TABLE)) {
2917                 sbi->s_li_request = NULL;
2918                 return 0;
2919         }
2920
2921         if (first_not_zeroed == ngroups) {
2922                 sbi->s_li_request = NULL;
2923                 return 0;
2924         }
2925
2926         elr = ext4_li_request_new(sb, first_not_zeroed);
2927         if (!elr)
2928                 return -ENOMEM;
2929
2930         mutex_lock(&ext4_li_mtx);
2931
2932         if (NULL == ext4_li_info) {
2933                 ret = ext4_li_info_new();
2934                 if (ret)
2935                         goto out;
2936         }
2937
2938         mutex_lock(&ext4_li_info->li_list_mtx);
2939         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
2940         mutex_unlock(&ext4_li_info->li_list_mtx);
2941
2942         sbi->s_li_request = elr;
2943
2944         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
2945                 ret = ext4_run_lazyinit_thread();
2946                 if (ret)
2947                         goto out;
2948         }
2949 out:
2950         mutex_unlock(&ext4_li_mtx);
2951         if (ret)
2952                 kfree(elr);
2953         return ret;
2954 }
2955
2956 /*
2957  * We do not need to lock anything since this is called on
2958  * module unload.
2959  */
2960 static void ext4_destroy_lazyinit_thread(void)
2961 {
2962         /*
2963          * If thread exited earlier
2964          * there's nothing to be done.
2965          */
2966         if (!ext4_li_info)
2967                 return;
2968
2969         ext4_clear_request_list();
2970
2971         while (ext4_li_info->li_task) {
2972                 wake_up(&ext4_li_info->li_wait_daemon);
2973                 wait_event(ext4_li_info->li_wait_task,
2974                            ext4_li_info->li_task == NULL);
2975         }
2976 }
2977
2978 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2979                                 __releases(kernel_lock)
2980                                 __acquires(kernel_lock)
2981 {
2982         char *orig_data = kstrdup(data, GFP_KERNEL);
2983         struct buffer_head *bh;
2984         struct ext4_super_block *es = NULL;
2985         struct ext4_sb_info *sbi;
2986         ext4_fsblk_t block;
2987         ext4_fsblk_t sb_block = get_sb_block(&data);
2988         ext4_fsblk_t logical_sb_block;
2989         unsigned long offset = 0;
2990         unsigned long journal_devnum = 0;
2991         unsigned long def_mount_opts;
2992         struct inode *root;
2993         char *cp;
2994         const char *descr;
2995         int ret = -ENOMEM;
2996         int blocksize;
2997         unsigned int db_count;
2998         unsigned int i;
2999         int needs_recovery, has_huge_files;
3000         __u64 blocks_count;
3001         int err;
3002         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3003         ext4_group_t first_not_zeroed;
3004
3005         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3006         if (!sbi)
3007                 goto out_free_orig;
3008
3009         sbi->s_blockgroup_lock =
3010                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3011         if (!sbi->s_blockgroup_lock) {
3012                 kfree(sbi);
3013                 goto out_free_orig;
3014         }
3015         sb->s_fs_info = sbi;
3016         sbi->s_mount_opt = 0;
3017         sbi->s_resuid = EXT4_DEF_RESUID;
3018         sbi->s_resgid = EXT4_DEF_RESGID;
3019         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3020         sbi->s_sb_block = sb_block;
3021         if (sb->s_bdev->bd_part)
3022                 sbi->s_sectors_written_start =
3023                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3024
3025         /* Cleanup superblock name */
3026         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3027                 *cp = '!';
3028
3029         ret = -EINVAL;
3030         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3031         if (!blocksize) {
3032                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3033                 goto out_fail;
3034         }
3035
3036         /*
3037          * The ext4 superblock will not be buffer aligned for other than 1kB
3038          * block sizes.  We need to calculate the offset from buffer start.
3039          */
3040         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3041                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3042                 offset = do_div(logical_sb_block, blocksize);
3043         } else {
3044                 logical_sb_block = sb_block;
3045         }
3046
3047         if (!(bh = sb_bread(sb, logical_sb_block))) {
3048                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3049                 goto out_fail;
3050         }
3051         /*
3052          * Note: s_es must be initialized as soon as possible because
3053          *       some ext4 macro-instructions depend on its value
3054          */
3055         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3056         sbi->s_es = es;
3057         sb->s_magic = le16_to_cpu(es->s_magic);
3058         if (sb->s_magic != EXT4_SUPER_MAGIC)
3059                 goto cantfind_ext4;
3060         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3061
3062         /* Set defaults before we parse the mount options */
3063         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3064         set_opt(sbi->s_mount_opt, INIT_INODE_TABLE);
3065         if (def_mount_opts & EXT4_DEFM_DEBUG)
3066                 set_opt(sbi->s_mount_opt, DEBUG);
3067         if (def_mount_opts & EXT4_DEFM_BSDGROUPS) {
3068                 ext4_msg(sb, KERN_WARNING, deprecated_msg, "bsdgroups",
3069                         "2.6.38");
3070                 set_opt(sbi->s_mount_opt, GRPID);
3071         }
3072         if (def_mount_opts & EXT4_DEFM_UID16)
3073                 set_opt(sbi->s_mount_opt, NO_UID32);
3074 #ifdef CONFIG_EXT4_FS_XATTR
3075         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
3076                 set_opt(sbi->s_mount_opt, XATTR_USER);
3077 #endif
3078 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3079         if (def_mount_opts & EXT4_DEFM_ACL)
3080                 set_opt(sbi->s_mount_opt, POSIX_ACL);
3081 #endif
3082         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3083                 set_opt(sbi->s_mount_opt, JOURNAL_DATA);
3084         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3085                 set_opt(sbi->s_mount_opt, ORDERED_DATA);
3086         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3087                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
3088
3089         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3090                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
3091         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3092                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
3093         else
3094                 set_opt(sbi->s_mount_opt, ERRORS_RO);
3095         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3096                 set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
3097         if (def_mount_opts & EXT4_DEFM_DISCARD)
3098                 set_opt(sbi->s_mount_opt, DISCARD);
3099
3100         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
3101         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
3102         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3103         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3104         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3105
3106         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3107                 set_opt(sbi->s_mount_opt, BARRIER);
3108
3109         /*
3110          * enable delayed allocation by default
3111          * Use -o nodelalloc to turn it off
3112          */
3113         if (!IS_EXT3_SB(sb) &&
3114             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3115                 set_opt(sbi->s_mount_opt, DELALLOC);
3116
3117         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3118                            &journal_devnum, &journal_ioprio, NULL, 0)) {
3119                 ext4_msg(sb, KERN_WARNING,
3120                          "failed to parse options in superblock: %s",
3121                          sbi->s_es->s_mount_opts);
3122         }
3123         if (!parse_options((char *) data, sb, &journal_devnum,
3124                            &journal_ioprio, NULL, 0))
3125                 goto failed_mount;
3126
3127         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3128                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3129
3130         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3131             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3132              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3133              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3134                 ext4_msg(sb, KERN_WARNING,
3135                        "feature flags set on rev 0 fs, "
3136                        "running e2fsck is recommended");
3137
3138         /*
3139          * Check feature flags regardless of the revision level, since we
3140          * previously didn't change the revision level when setting the flags,
3141          * so there is a chance incompat flags are set on a rev 0 filesystem.
3142          */
3143         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3144                 goto failed_mount;
3145
3146         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3147
3148         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3149             blocksize > EXT4_MAX_BLOCK_SIZE) {
3150                 ext4_msg(sb, KERN_ERR,
3151                        "Unsupported filesystem blocksize %d", blocksize);
3152                 goto failed_mount;
3153         }
3154
3155         if (sb->s_blocksize != blocksize) {
3156                 /* Validate the filesystem blocksize */
3157                 if (!sb_set_blocksize(sb, blocksize)) {
3158                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3159                                         blocksize);
3160                         goto failed_mount;
3161                 }
3162
3163                 brelse(bh);
3164                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3165                 offset = do_div(logical_sb_block, blocksize);
3166                 bh = sb_bread(sb, logical_sb_block);
3167                 if (!bh) {
3168                         ext4_msg(sb, KERN_ERR,
3169                                "Can't read superblock on 2nd try");
3170                         goto failed_mount;
3171                 }
3172                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
3173                 sbi->s_es = es;
3174                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3175                         ext4_msg(sb, KERN_ERR,
3176                                "Magic mismatch, very weird!");
3177                         goto failed_mount;
3178                 }
3179         }
3180
3181         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3182                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3183         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3184                                                       has_huge_files);
3185         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3186
3187         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3188                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3189                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3190         } else {
3191                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3192                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3193                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3194                     (!is_power_of_2(sbi->s_inode_size)) ||
3195                     (sbi->s_inode_size > blocksize)) {
3196                         ext4_msg(sb, KERN_ERR,
3197                                "unsupported inode size: %d",
3198                                sbi->s_inode_size);
3199                         goto failed_mount;
3200                 }
3201                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3202                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3203         }
3204
3205         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3206         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3207                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3208                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3209                     !is_power_of_2(sbi->s_desc_size)) {
3210                         ext4_msg(sb, KERN_ERR,
3211                                "unsupported descriptor size %lu",
3212                                sbi->s_desc_size);
3213                         goto failed_mount;
3214                 }
3215         } else
3216                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3217
3218         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3219         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3220         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3221                 goto cantfind_ext4;
3222
3223         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3224         if (sbi->s_inodes_per_block == 0)
3225                 goto cantfind_ext4;
3226         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3227                                         sbi->s_inodes_per_block;
3228         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3229         sbi->s_sbh = bh;
3230         sbi->s_mount_state = le16_to_cpu(es->s_state);
3231         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3232         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3233
3234         for (i = 0; i < 4; i++)
3235                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3236         sbi->s_def_hash_version = es->s_def_hash_version;
3237         i = le32_to_cpu(es->s_flags);
3238         if (i & EXT2_FLAGS_UNSIGNED_HASH)
3239                 sbi->s_hash_unsigned = 3;
3240         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3241 #ifdef __CHAR_UNSIGNED__
3242                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3243                 sbi->s_hash_unsigned = 3;
3244 #else
3245                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3246 #endif
3247                 sb->s_dirt = 1;
3248         }
3249
3250         if (sbi->s_blocks_per_group > blocksize * 8) {
3251                 ext4_msg(sb, KERN_ERR,
3252                        "#blocks per group too big: %lu",
3253                        sbi->s_blocks_per_group);
3254                 goto failed_mount;
3255         }
3256         if (sbi->s_inodes_per_group > blocksize * 8) {
3257                 ext4_msg(sb, KERN_ERR,
3258                        "#inodes per group too big: %lu",
3259                        sbi->s_inodes_per_group);
3260                 goto failed_mount;
3261         }
3262
3263         /*
3264          * Test whether we have more sectors than will fit in sector_t,
3265          * and whether the max offset is addressable by the page cache.
3266          */
3267         err = generic_check_addressable(sb->s_blocksize_bits,
3268                                         ext4_blocks_count(es));
3269         if (err) {
3270                 ext4_msg(sb, KERN_ERR, "filesystem"
3271                          " too large to mount safely on this system");
3272                 if (sizeof(sector_t) < 8)
3273                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3274                 ret = err;
3275                 goto failed_mount;
3276         }
3277
3278         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3279                 goto cantfind_ext4;
3280
3281         /* check blocks count against device size */
3282         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3283         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3284                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3285                        "exceeds size of device (%llu blocks)",
3286                        ext4_blocks_count(es), blocks_count);
3287                 goto failed_mount;
3288         }
3289
3290         /*
3291          * It makes no sense for the first data block to be beyond the end
3292          * of the filesystem.
3293          */
3294         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3295                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
3296                          "block %u is beyond end of filesystem (%llu)",
3297                          le32_to_cpu(es->s_first_data_block),
3298                          ext4_blocks_count(es));
3299                 goto failed_mount;
3300         }
3301         blocks_count = (ext4_blocks_count(es) -
3302                         le32_to_cpu(es->s_first_data_block) +
3303                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3304         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3305         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3306                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3307                        "(block count %llu, first data block %u, "
3308                        "blocks per group %lu)", sbi->s_groups_count,
3309                        ext4_blocks_count(es),
3310                        le32_to_cpu(es->s_first_data_block),
3311                        EXT4_BLOCKS_PER_GROUP(sb));
3312                 goto failed_mount;
3313         }
3314         sbi->s_groups_count = blocks_count;
3315         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3316                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3317         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3318                    EXT4_DESC_PER_BLOCK(sb);
3319         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
3320                                     GFP_KERNEL);
3321         if (sbi->s_group_desc == NULL) {
3322                 ext4_msg(sb, KERN_ERR, "not enough memory");
3323                 goto failed_mount;
3324         }
3325
3326 #ifdef CONFIG_PROC_FS
3327         if (ext4_proc_root)
3328                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3329 #endif
3330
3331         bgl_lock_init(sbi->s_blockgroup_lock);
3332
3333         for (i = 0; i < db_count; i++) {
3334                 block = descriptor_loc(sb, logical_sb_block, i);
3335                 sbi->s_group_desc[i] = sb_bread(sb, block);
3336                 if (!sbi->s_group_desc[i]) {
3337                         ext4_msg(sb, KERN_ERR,
3338                                "can't read group descriptor %d", i);
3339                         db_count = i;
3340                         goto failed_mount2;
3341                 }
3342         }
3343         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3344                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3345                 goto failed_mount2;
3346         }
3347         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3348                 if (!ext4_fill_flex_info(sb)) {
3349                         ext4_msg(sb, KERN_ERR,
3350                                "unable to initialize "
3351                                "flex_bg meta info!");
3352                         goto failed_mount2;
3353                 }
3354
3355         sbi->s_gdb_count = db_count;
3356         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3357         spin_lock_init(&sbi->s_next_gen_lock);
3358
3359         err = percpu_counter_init(&sbi->s_freeblocks_counter,
3360                         ext4_count_free_blocks(sb));
3361         if (!err) {
3362                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
3363                                 ext4_count_free_inodes(sb));
3364         }
3365         if (!err) {
3366                 err = percpu_counter_init(&sbi->s_dirs_counter,
3367                                 ext4_count_dirs(sb));
3368         }
3369         if (!err) {
3370                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
3371         }
3372         if (err) {
3373                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3374                 goto failed_mount3;
3375         }
3376
3377         sbi->s_stripe = ext4_get_stripe_size(sbi);
3378         sbi->s_max_writeback_mb_bump = 128;
3379
3380         /*
3381          * set up enough so that it can read an inode
3382          */
3383         if (!test_opt(sb, NOLOAD) &&
3384             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3385                 sb->s_op = &ext4_sops;
3386         else
3387                 sb->s_op = &ext4_nojournal_sops;
3388         sb->s_export_op = &ext4_export_ops;
3389         sb->s_xattr = ext4_xattr_handlers;
3390 #ifdef CONFIG_QUOTA
3391         sb->s_qcop = &ext4_qctl_operations;
3392         sb->dq_op = &ext4_quota_operations;
3393 #endif
3394         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3395         mutex_init(&sbi->s_orphan_lock);
3396         mutex_init(&sbi->s_resize_lock);
3397
3398         sb->s_root = NULL;
3399
3400         needs_recovery = (es->s_last_orphan != 0 ||
3401                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3402                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3403
3404         /*
3405          * The first inode we look at is the journal inode.  Don't try
3406          * root first: it may be modified in the journal!
3407          */
3408         if (!test_opt(sb, NOLOAD) &&
3409             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3410                 if (ext4_load_journal(sb, es, journal_devnum))
3411                         goto failed_mount3;
3412         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3413               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3414                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3415                        "suppressed and not mounted read-only");
3416                 goto failed_mount_wq;
3417         } else {
3418                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
3419                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
3420                 sbi->s_journal = NULL;
3421                 needs_recovery = 0;
3422                 goto no_journal;
3423         }
3424
3425         if (ext4_blocks_count(es) > 0xffffffffULL &&
3426             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3427                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3428                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3429                 goto failed_mount_wq;
3430         }
3431
3432         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3433                 jbd2_journal_set_features(sbi->s_journal,
3434                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3435                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3436         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3437                 jbd2_journal_set_features(sbi->s_journal,
3438                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
3439                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3440                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3441         } else {
3442                 jbd2_journal_clear_features(sbi->s_journal,
3443                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3444                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3445         }
3446
3447         /* We have now updated the journal if required, so we can
3448          * validate the data journaling mode. */
3449         switch (test_opt(sb, DATA_FLAGS)) {
3450         case 0:
3451                 /* No mode set, assume a default based on the journal
3452                  * capabilities: ORDERED_DATA if the journal can
3453                  * cope, else JOURNAL_DATA
3454                  */
3455                 if (jbd2_journal_check_available_features
3456                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3457                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
3458                 else
3459                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
3460                 break;
3461
3462         case EXT4_MOUNT_ORDERED_DATA:
3463         case EXT4_MOUNT_WRITEBACK_DATA:
3464                 if (!jbd2_journal_check_available_features
3465                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3466                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3467                                "requested data journaling mode");
3468                         goto failed_mount_wq;
3469                 }
3470         default:
3471                 break;
3472         }
3473         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3474
3475         /*
3476          * The journal may have updated the bg summary counts, so we
3477          * need to update the global counters.
3478          */
3479         percpu_counter_set(&sbi->s_freeblocks_counter,
3480                            ext4_count_free_blocks(sb));
3481         percpu_counter_set(&sbi->s_freeinodes_counter,
3482                            ext4_count_free_inodes(sb));
3483         percpu_counter_set(&sbi->s_dirs_counter,
3484                            ext4_count_dirs(sb));
3485         percpu_counter_set(&sbi->s_dirtyblocks_counter, 0);
3486
3487 no_journal:
3488         EXT4_SB(sb)->dio_unwritten_wq = create_workqueue("ext4-dio-unwritten");
3489         if (!EXT4_SB(sb)->dio_unwritten_wq) {
3490                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
3491                 goto failed_mount_wq;
3492         }
3493
3494         /*
3495          * The jbd2_journal_load will have done any necessary log recovery,
3496          * so we can safely mount the rest of the filesystem now.
3497          */
3498
3499         root = ext4_iget(sb, EXT4_ROOT_INO);
3500         if (IS_ERR(root)) {
3501                 ext4_msg(sb, KERN_ERR, "get root inode failed");
3502                 ret = PTR_ERR(root);
3503                 goto failed_mount4;
3504         }
3505         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3506                 iput(root);
3507                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3508                 goto failed_mount4;
3509         }
3510         sb->s_root = d_alloc_root(root);
3511         if (!sb->s_root) {
3512                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
3513                 iput(root);
3514                 ret = -ENOMEM;
3515                 goto failed_mount4;
3516         }
3517
3518         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
3519
3520         /* determine the minimum size of new large inodes, if present */
3521         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3522                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3523                                                      EXT4_GOOD_OLD_INODE_SIZE;
3524                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3525                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
3526                         if (sbi->s_want_extra_isize <
3527                             le16_to_cpu(es->s_want_extra_isize))
3528                                 sbi->s_want_extra_isize =
3529                                         le16_to_cpu(es->s_want_extra_isize);
3530                         if (sbi->s_want_extra_isize <
3531                             le16_to_cpu(es->s_min_extra_isize))
3532                                 sbi->s_want_extra_isize =
3533                                         le16_to_cpu(es->s_min_extra_isize);
3534                 }
3535         }
3536         /* Check if enough inode space is available */
3537         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3538                                                         sbi->s_inode_size) {
3539                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3540                                                        EXT4_GOOD_OLD_INODE_SIZE;
3541                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
3542                          "available");
3543         }
3544
3545         if (test_opt(sb, DELALLOC) &&
3546             (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
3547                 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
3548                          "requested data journaling mode");
3549                 clear_opt(sbi->s_mount_opt, DELALLOC);
3550         }
3551         if (test_opt(sb, DIOREAD_NOLOCK)) {
3552                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3553                         ext4_msg(sb, KERN_WARNING, "Ignoring dioread_nolock "
3554                                 "option - requested data journaling mode");
3555                         clear_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
3556                 }
3557                 if (sb->s_blocksize < PAGE_SIZE) {
3558                         ext4_msg(sb, KERN_WARNING, "Ignoring dioread_nolock "
3559                                 "option - block size is too small");
3560                         clear_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
3561                 }
3562         }
3563
3564         err = ext4_setup_system_zone(sb);
3565         if (err) {
3566                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3567                          "zone (%d)", err);
3568                 goto failed_mount4;
3569         }
3570
3571         ext4_ext_init(sb);
3572         err = ext4_mb_init(sb, needs_recovery);
3573         if (err) {
3574                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3575                          err);
3576                 goto failed_mount4;
3577         }
3578
3579         err = ext4_register_li_request(sb, first_not_zeroed);
3580         if (err)
3581                 goto failed_mount4;
3582
3583         sbi->s_kobj.kset = ext4_kset;
3584         init_completion(&sbi->s_kobj_unregister);
3585         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3586                                    "%s", sb->s_id);
3587         if (err) {
3588                 ext4_mb_release(sb);
3589                 ext4_ext_release(sb);
3590                 goto failed_mount4;
3591         };
3592
3593         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3594         ext4_orphan_cleanup(sb, es);
3595         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3596         if (needs_recovery) {
3597                 ext4_msg(sb, KERN_INFO, "recovery complete");
3598                 ext4_mark_recovery_complete(sb, es);
3599         }
3600         if (EXT4_SB(sb)->s_journal) {
3601                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3602                         descr = " journalled data mode";
3603                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3604                         descr = " ordered data mode";
3605                 else
3606                         descr = " writeback data mode";
3607         } else
3608                 descr = "out journal";
3609
3610         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3611                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
3612                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
3613
3614         init_timer(&sbi->s_err_report);
3615         sbi->s_err_report.function = print_daily_error_info;
3616         sbi->s_err_report.data = (unsigned long) sb;
3617         if (es->s_error_count)
3618                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
3619
3620         kfree(orig_data);
3621         return 0;
3622
3623 cantfind_ext4:
3624         if (!silent)
3625                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3626         goto failed_mount;
3627
3628 failed_mount4:
3629         ext4_msg(sb, KERN_ERR, "mount failed");
3630         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
3631 failed_mount_wq:
3632         ext4_release_system_zone(sb);
3633         if (sbi->s_journal) {
3634                 jbd2_journal_destroy(sbi->s_journal);
3635                 sbi->s_journal = NULL;
3636         }
3637 failed_mount3:
3638         if (sbi->s_flex_groups) {
3639                 if (is_vmalloc_addr(sbi->s_flex_groups))
3640                         vfree(sbi->s_flex_groups);
3641                 else
3642                         kfree(sbi->s_flex_groups);
3643         }
3644         percpu_counter_destroy(&sbi->s_freeblocks_counter);
3645         percpu_counter_destroy(&sbi->s_freeinodes_counter);
3646         percpu_counter_destroy(&sbi->s_dirs_counter);
3647         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
3648 failed_mount2:
3649         for (i = 0; i < db_count; i++)
3650                 brelse(sbi->s_group_desc[i]);
3651         kfree(sbi->s_group_desc);
3652 failed_mount:
3653         if (sbi->s_proc) {
3654                 remove_proc_entry(sb->s_id, ext4_proc_root);
3655         }
3656 #ifdef CONFIG_QUOTA
3657         for (i = 0; i < MAXQUOTAS; i++)
3658                 kfree(sbi->s_qf_names[i]);
3659 #endif
3660         ext4_blkdev_remove(sbi);
3661         brelse(bh);
3662 out_fail:
3663         sb->s_fs_info = NULL;
3664         kfree(sbi->s_blockgroup_lock);
3665         kfree(sbi);
3666 out_free_orig:
3667         kfree(orig_data);
3668         return ret;
3669 }
3670
3671 /*
3672  * Setup any per-fs journal parameters now.  We'll do this both on
3673  * initial mount, once the journal has been initialised but before we've
3674  * done any recovery; and again on any subsequent remount.
3675  */
3676 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
3677 {
3678         struct ext4_sb_info *sbi = EXT4_SB(sb);
3679
3680         journal->j_commit_interval = sbi->s_commit_interval;
3681         journal->j_min_batch_time = sbi->s_min_batch_time;
3682         journal->j_max_batch_time = sbi->s_max_batch_time;
3683
3684         write_lock(&journal->j_state_lock);
3685         if (test_opt(sb, BARRIER))
3686                 journal->j_flags |= JBD2_BARRIER;
3687         else
3688                 journal->j_flags &= ~JBD2_BARRIER;
3689         if (test_opt(sb, DATA_ERR_ABORT))
3690                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3691         else
3692                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3693         write_unlock(&journal->j_state_lock);
3694 }
3695
3696 static journal_t *ext4_get_journal(struct super_block *sb,
3697                                    unsigned int journal_inum)
3698 {
3699         struct inode *journal_inode;
3700         journal_t *journal;
3701
3702         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3703
3704         /* First, test for the existence of a valid inode on disk.  Bad
3705          * things happen if we iget() an unused inode, as the subsequent
3706          * iput() will try to delete it. */
3707
3708         journal_inode = ext4_iget(sb, journal_inum);
3709         if (IS_ERR(journal_inode)) {
3710                 ext4_msg(sb, KERN_ERR, "no journal found");
3711                 return NULL;
3712         }
3713         if (!journal_inode->i_nlink) {
3714                 make_bad_inode(journal_inode);
3715                 iput(journal_inode);
3716                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3717                 return NULL;
3718         }
3719
3720         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3721                   journal_inode, journal_inode->i_size);
3722         if (!S_ISREG(journal_inode->i_mode)) {
3723                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3724                 iput(journal_inode);
3725                 return NULL;
3726         }
3727
3728         journal = jbd2_journal_init_inode(journal_inode);
3729         if (!journal) {
3730                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3731                 iput(journal_inode);
3732                 return NULL;
3733         }
3734         journal->j_private = sb;
3735         ext4_init_journal_params(sb, journal);
3736         return journal;
3737 }
3738
3739 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3740                                        dev_t j_dev)
3741 {
3742         struct buffer_head *bh;
3743         journal_t *journal;
3744         ext4_fsblk_t start;
3745         ext4_fsblk_t len;
3746         int hblock, blocksize;
3747         ext4_fsblk_t sb_block;
3748         unsigned long offset;
3749         struct ext4_super_block *es;
3750         struct block_device *bdev;
3751
3752         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3753
3754         bdev = ext4_blkdev_get(j_dev, sb);
3755         if (bdev == NULL)
3756                 return NULL;
3757
3758         if (bd_claim(bdev, sb)) {
3759                 ext4_msg(sb, KERN_ERR,
3760                         "failed to claim external journal device");
3761                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3762                 return NULL;
3763         }
3764
3765         blocksize = sb->s_blocksize;
3766         hblock = bdev_logical_block_size(bdev);
3767         if (blocksize < hblock) {
3768                 ext4_msg(sb, KERN_ERR,
3769                         "blocksize too small for journal device");
3770                 goto out_bdev;
3771         }
3772
3773         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3774         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3775         set_blocksize(bdev, blocksize);
3776         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3777                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3778                        "external journal");
3779                 goto out_bdev;
3780         }
3781
3782         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3783         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3784             !(le32_to_cpu(es->s_feature_incompat) &
3785               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3786                 ext4_msg(sb, KERN_ERR, "external journal has "
3787                                         "bad superblock");
3788                 brelse(bh);
3789                 goto out_bdev;
3790         }
3791
3792         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3793                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3794                 brelse(bh);
3795                 goto out_bdev;
3796         }
3797
3798         len = ext4_blocks_count(es);
3799         start = sb_block + 1;
3800         brelse(bh);     /* we're done with the superblock */
3801
3802         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3803                                         start, len, blocksize);
3804         if (!journal) {
3805                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3806                 goto out_bdev;
3807         }
3808         journal->j_private = sb;
3809         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3810         wait_on_buffer(journal->j_sb_buffer);
3811         if (!buffer_uptodate(journal->j_sb_buffer)) {
3812                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3813                 goto out_journal;
3814         }
3815         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3816                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3817                                         "user (unsupported) - %d",
3818                         be32_to_cpu(journal->j_superblock->s_nr_users));
3819                 goto out_journal;
3820         }
3821         EXT4_SB(sb)->journal_bdev = bdev;
3822         ext4_init_journal_params(sb, journal);
3823         return journal;
3824
3825 out_journal:
3826         jbd2_journal_destroy(journal);
3827 out_bdev:
3828         ext4_blkdev_put(bdev);
3829         return NULL;
3830 }
3831
3832 static int ext4_load_journal(struct super_block *sb,
3833                              struct ext4_super_block *es,
3834                              unsigned long journal_devnum)
3835 {
3836         journal_t *journal;
3837         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3838         dev_t journal_dev;
3839         int err = 0;
3840         int really_read_only;
3841
3842         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3843
3844         if (journal_devnum &&
3845             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3846                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3847                         "numbers have changed");
3848                 journal_dev = new_decode_dev(journal_devnum);
3849         } else
3850                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3851
3852         really_read_only = bdev_read_only(sb->s_bdev);
3853
3854         /*
3855          * Are we loading a blank journal or performing recovery after a
3856          * crash?  For recovery, we need to check in advance whether we
3857          * can get read-write access to the device.
3858          */
3859         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3860                 if (sb->s_flags & MS_RDONLY) {
3861                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3862                                         "required on readonly filesystem");
3863                         if (really_read_only) {
3864                                 ext4_msg(sb, KERN_ERR, "write access "
3865                                         "unavailable, cannot proceed");
3866                                 return -EROFS;
3867                         }
3868                         ext4_msg(sb, KERN_INFO, "write access will "
3869                                "be enabled during recovery");
3870                 }
3871         }
3872
3873         if (journal_inum && journal_dev) {
3874                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3875                        "and inode journals!");
3876                 return -EINVAL;
3877         }
3878
3879         if (journal_inum) {
3880                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3881                         return -EINVAL;
3882         } else {
3883                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3884                         return -EINVAL;
3885         }
3886
3887         if (!(journal->j_flags & JBD2_BARRIER))
3888                 ext4_msg(sb, KERN_INFO, "barriers disabled");
3889
3890         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3891                 err = jbd2_journal_update_format(journal);
3892                 if (err)  {
3893                         ext4_msg(sb, KERN_ERR, "error updating journal");
3894                         jbd2_journal_destroy(journal);
3895                         return err;
3896                 }
3897         }
3898
3899         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3900                 err = jbd2_journal_wipe(journal, !really_read_only);
3901         if (!err) {
3902                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
3903                 if (save)
3904                         memcpy(save, ((char *) es) +
3905                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
3906                 err = jbd2_journal_load(journal);
3907                 if (save)
3908                         memcpy(((char *) es) + EXT4_S_ERR_START,
3909                                save, EXT4_S_ERR_LEN);
3910                 kfree(save);
3911         }
3912
3913         if (err) {
3914                 ext4_msg(sb, KERN_ERR, "error loading journal");
3915                 jbd2_journal_destroy(journal);
3916                 return err;
3917         }
3918
3919         EXT4_SB(sb)->s_journal = journal;
3920         ext4_clear_journal_err(sb, es);
3921
3922         if (!really_read_only && journal_devnum &&
3923             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3924                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3925
3926                 /* Make sure we flush the recovery flag to disk. */
3927                 ext4_commit_super(sb, 1);
3928         }
3929
3930         return 0;
3931 }
3932
3933 static int ext4_commit_super(struct super_block *sb, int sync)
3934 {
3935         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3936         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3937         int error = 0;
3938
3939         if (!sbh)
3940                 return error;
3941         if (buffer_write_io_error(sbh)) {
3942                 /*
3943                  * Oh, dear.  A previous attempt to write the
3944                  * superblock failed.  This could happen because the
3945                  * USB device was yanked out.  Or it could happen to
3946                  * be a transient write error and maybe the block will
3947                  * be remapped.  Nothing we can do but to retry the
3948                  * write and hope for the best.
3949                  */
3950                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
3951                        "superblock detected");
3952                 clear_buffer_write_io_error(sbh);
3953                 set_buffer_uptodate(sbh);
3954         }
3955         /*
3956          * If the file system is mounted read-only, don't update the
3957          * superblock write time.  This avoids updating the superblock
3958          * write time when we are mounting the root file system
3959          * read/only but we need to replay the journal; at that point,
3960          * for people who are east of GMT and who make their clock
3961          * tick in localtime for Windows bug-for-bug compatibility,
3962          * the clock is set in the future, and this will cause e2fsck
3963          * to complain and force a full file system check.
3964          */
3965         if (!(sb->s_flags & MS_RDONLY))
3966                 es->s_wtime = cpu_to_le32(get_seconds());
3967         if (sb->s_bdev->bd_part)
3968                 es->s_kbytes_written =
3969                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
3970                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
3971                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
3972         else
3973                 es->s_kbytes_written =
3974                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
3975         ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
3976                                            &EXT4_SB(sb)->s_freeblocks_counter));
3977         es->s_free_inodes_count =
3978                 cpu_to_le32(percpu_counter_sum_positive(
3979                                 &EXT4_SB(sb)->s_freeinodes_counter));
3980         sb->s_dirt = 0;
3981         BUFFER_TRACE(sbh, "marking dirty");
3982         mark_buffer_dirty(sbh);
3983         if (sync) {
3984                 error = sync_dirty_buffer(sbh);
3985                 if (error)
3986                         return error;
3987
3988                 error = buffer_write_io_error(sbh);
3989                 if (error) {
3990                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
3991                                "superblock");
3992                         clear_buffer_write_io_error(sbh);
3993                         set_buffer_uptodate(sbh);
3994                 }
3995         }
3996         return error;
3997 }
3998
3999 /*
4000  * Have we just finished recovery?  If so, and if we are mounting (or
4001  * remounting) the filesystem readonly, then we will end up with a
4002  * consistent fs on disk.  Record that fact.
4003  */
4004 static void ext4_mark_recovery_complete(struct super_block *sb,
4005                                         struct ext4_super_block *es)
4006 {
4007         journal_t *journal = EXT4_SB(sb)->s_journal;
4008
4009         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4010                 BUG_ON(journal != NULL);
4011                 return;
4012         }
4013         jbd2_journal_lock_updates(journal);
4014         if (jbd2_journal_flush(journal) < 0)
4015                 goto out;
4016
4017         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4018             sb->s_flags & MS_RDONLY) {
4019                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4020                 ext4_commit_super(sb, 1);
4021         }
4022
4023 out:
4024         jbd2_journal_unlock_updates(journal);
4025 }
4026
4027 /*
4028  * If we are mounting (or read-write remounting) a filesystem whose journal
4029  * has recorded an error from a previous lifetime, move that error to the
4030  * main filesystem now.
4031  */
4032 static void ext4_clear_journal_err(struct super_block *sb,
4033                                    struct ext4_super_block *es)
4034 {
4035         journal_t *journal;
4036         int j_errno;
4037         const char *errstr;
4038
4039         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4040
4041         journal = EXT4_SB(sb)->s_journal;
4042
4043         /*
4044          * Now check for any error status which may have been recorded in the
4045          * journal by a prior ext4_error() or ext4_abort()
4046          */
4047
4048         j_errno = jbd2_journal_errno(journal);
4049         if (j_errno) {
4050                 char nbuf[16];
4051
4052                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4053                 ext4_warning(sb, "Filesystem error recorded "
4054                              "from previous mount: %s", errstr);
4055                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4056
4057                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4058                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4059                 ext4_commit_super(sb, 1);
4060
4061                 jbd2_journal_clear_err(journal);
4062         }
4063 }
4064
4065 /*
4066  * Force the running and committing transactions to commit,
4067  * and wait on the commit.
4068  */
4069 int ext4_force_commit(struct super_block *sb)
4070 {
4071         journal_t *journal;
4072         int ret = 0;
4073
4074         if (sb->s_flags & MS_RDONLY)
4075                 return 0;
4076
4077         journal = EXT4_SB(sb)->s_journal;
4078         if (journal) {
4079                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
4080                 ret = ext4_journal_force_commit(journal);
4081         }
4082
4083         return ret;
4084 }
4085
4086 static void ext4_write_super(struct super_block *sb)
4087 {
4088         lock_super(sb);
4089         ext4_commit_super(sb, 1);
4090         unlock_super(sb);
4091 }
4092
4093 static int ext4_sync_fs(struct super_block *sb, int wait)
4094 {
4095         int ret = 0;
4096         tid_t target;
4097         struct ext4_sb_info *sbi = EXT4_SB(sb);
4098
4099         trace_ext4_sync_fs(sb, wait);
4100         flush_workqueue(sbi->dio_unwritten_wq);
4101         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4102                 if (wait)
4103                         jbd2_log_wait_commit(sbi->s_journal, target);
4104         }
4105         return ret;
4106 }
4107
4108 /*
4109  * LVM calls this function before a (read-only) snapshot is created.  This
4110  * gives us a chance to flush the journal completely and mark the fs clean.
4111  */
4112 static int ext4_freeze(struct super_block *sb)
4113 {
4114         int error = 0;
4115         journal_t *journal;
4116
4117         if (sb->s_flags & MS_RDONLY)
4118                 return 0;
4119
4120         journal = EXT4_SB(sb)->s_journal;
4121
4122         /* Now we set up the journal barrier. */
4123         jbd2_journal_lock_updates(journal);
4124
4125         /*
4126          * Don't clear the needs_recovery flag if we failed to flush
4127          * the journal.
4128          */
4129         error = jbd2_journal_flush(journal);
4130         if (error < 0)
4131                 goto out;
4132
4133         /* Journal blocked and flushed, clear needs_recovery flag. */
4134         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4135         error = ext4_commit_super(sb, 1);
4136 out:
4137         /* we rely on s_frozen to stop further updates */
4138         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4139         return error;
4140 }
4141
4142 /*
4143  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4144  * flag here, even though the filesystem is not technically dirty yet.
4145  */
4146 static int ext4_unfreeze(struct super_block *sb)
4147 {
4148         if (sb->s_flags & MS_RDONLY)
4149                 return 0;
4150
4151         lock_super(sb);
4152         /* Reset the needs_recovery flag before the fs is unlocked. */
4153         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4154         ext4_commit_super(sb, 1);
4155         unlock_super(sb);
4156         return 0;
4157 }
4158
4159 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4160 {
4161         struct ext4_super_block *es;
4162         struct ext4_sb_info *sbi = EXT4_SB(sb);
4163         ext4_fsblk_t n_blocks_count = 0;
4164         unsigned long old_sb_flags;
4165         struct ext4_mount_options old_opts;
4166         int enable_quota = 0;
4167         ext4_group_t g;
4168         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4169         int err;
4170 #ifdef CONFIG_QUOTA
4171         int i;
4172 #endif
4173         char *orig_data = kstrdup(data, GFP_KERNEL);
4174
4175         /* Store the original options */
4176         lock_super(sb);
4177         old_sb_flags = sb->s_flags;
4178         old_opts.s_mount_opt = sbi->s_mount_opt;
4179         old_opts.s_resuid = sbi->s_resuid;
4180         old_opts.s_resgid = sbi->s_resgid;
4181         old_opts.s_commit_interval = sbi->s_commit_interval;
4182         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4183         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4184 #ifdef CONFIG_QUOTA
4185         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4186         for (i = 0; i < MAXQUOTAS; i++)
4187                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
4188 #endif
4189         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4190                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4191
4192         /*
4193          * Allow the "check" option to be passed as a remount option.
4194          */
4195         if (!parse_options(data, sb, NULL, &journal_ioprio,
4196                            &n_blocks_count, 1)) {
4197                 err = -EINVAL;
4198                 goto restore_opts;
4199         }
4200
4201         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4202                 ext4_abort(sb, "Abort forced by user");
4203
4204         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4205                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4206
4207         es = sbi->s_es;
4208
4209         if (sbi->s_journal) {
4210                 ext4_init_journal_params(sb, sbi->s_journal);
4211                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4212         }
4213
4214         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
4215                 n_blocks_count > ext4_blocks_count(es)) {
4216                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4217                         err = -EROFS;
4218                         goto restore_opts;
4219                 }
4220
4221                 if (*flags & MS_RDONLY) {
4222                         err = dquot_suspend(sb, -1);
4223                         if (err < 0)
4224                                 goto restore_opts;
4225
4226                         /*
4227                          * First of all, the unconditional stuff we have to do
4228                          * to disable replay of the journal when we next remount
4229                          */
4230                         sb->s_flags |= MS_RDONLY;
4231
4232                         /*
4233                          * OK, test if we are remounting a valid rw partition
4234                          * readonly, and if so set the rdonly flag and then
4235                          * mark the partition as valid again.
4236                          */
4237                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4238                             (sbi->s_mount_state & EXT4_VALID_FS))
4239                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4240
4241                         if (sbi->s_journal)
4242                                 ext4_mark_recovery_complete(sb, es);
4243                 } else {
4244                         /* Make sure we can mount this feature set readwrite */
4245                         if (!ext4_feature_set_ok(sb, 0)) {
4246                                 err = -EROFS;
4247                                 goto restore_opts;
4248                         }
4249                         /*
4250                          * Make sure the group descriptor checksums
4251                          * are sane.  If they aren't, refuse to remount r/w.
4252                          */
4253                         for (g = 0; g < sbi->s_groups_count; g++) {
4254                                 struct ext4_group_desc *gdp =
4255                                         ext4_get_group_desc(sb, g, NULL);
4256
4257                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
4258                                         ext4_msg(sb, KERN_ERR,
4259                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4260                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4261                                                le16_to_cpu(gdp->bg_checksum));
4262                                         err = -EINVAL;
4263                                         goto restore_opts;
4264                                 }
4265                         }
4266
4267                         /*
4268                          * If we have an unprocessed orphan list hanging
4269                          * around from a previously readonly bdev mount,
4270                          * require a full umount/remount for now.
4271                          */
4272                         if (es->s_last_orphan) {
4273                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4274                                        "remount RDWR because of unprocessed "
4275                                        "orphan inode list.  Please "
4276                                        "umount/remount instead");
4277                                 err = -EINVAL;
4278                                 goto restore_opts;
4279                         }
4280
4281                         /*
4282                          * Mounting a RDONLY partition read-write, so reread
4283                          * and store the current valid flag.  (It may have
4284                          * been changed by e2fsck since we originally mounted
4285                          * the partition.)
4286                          */
4287                         if (sbi->s_journal)
4288                                 ext4_clear_journal_err(sb, es);
4289                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4290                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
4291                                 goto restore_opts;
4292                         if (!ext4_setup_super(sb, es, 0))
4293                                 sb->s_flags &= ~MS_RDONLY;
4294                         enable_quota = 1;
4295                 }
4296         }
4297
4298         /*
4299          * Reinitialize lazy itable initialization thread based on
4300          * current settings
4301          */
4302         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4303                 ext4_unregister_li_request(sb);
4304         else {
4305                 ext4_group_t first_not_zeroed;
4306                 first_not_zeroed = ext4_has_uninit_itable(sb);
4307                 ext4_register_li_request(sb, first_not_zeroed);
4308         }
4309
4310         ext4_setup_system_zone(sb);
4311         if (sbi->s_journal == NULL)
4312                 ext4_commit_super(sb, 1);
4313
4314 #ifdef CONFIG_QUOTA
4315         /* Release old quota file names */
4316         for (i = 0; i < MAXQUOTAS; i++)
4317                 if (old_opts.s_qf_names[i] &&
4318                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4319                         kfree(old_opts.s_qf_names[i]);
4320 #endif
4321         unlock_super(sb);
4322         if (enable_quota)
4323                 dquot_resume(sb, -1);
4324
4325         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4326         kfree(orig_data);
4327         return 0;
4328
4329 restore_opts:
4330         sb->s_flags = old_sb_flags;
4331         sbi->s_mount_opt = old_opts.s_mount_opt;
4332         sbi->s_resuid = old_opts.s_resuid;
4333         sbi->s_resgid = old_opts.s_resgid;
4334         sbi->s_commit_interval = old_opts.s_commit_interval;
4335         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4336         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4337 #ifdef CONFIG_QUOTA
4338         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4339         for (i = 0; i < MAXQUOTAS; i++) {
4340                 if (sbi->s_qf_names[i] &&
4341                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4342                         kfree(sbi->s_qf_names[i]);
4343                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4344         }
4345 #endif
4346         unlock_super(sb);
4347         kfree(orig_data);
4348         return err;
4349 }
4350
4351 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4352 {
4353         struct super_block *sb = dentry->d_sb;
4354         struct ext4_sb_info *sbi = EXT4_SB(sb);
4355         struct ext4_super_block *es = sbi->s_es;
4356         u64 fsid;
4357
4358         if (test_opt(sb, MINIX_DF)) {
4359                 sbi->s_overhead_last = 0;
4360         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
4361                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4362                 ext4_fsblk_t overhead = 0;
4363
4364                 /*
4365                  * Compute the overhead (FS structures).  This is constant
4366                  * for a given filesystem unless the number of block groups
4367                  * changes so we cache the previous value until it does.
4368                  */
4369
4370                 /*
4371                  * All of the blocks before first_data_block are
4372                  * overhead
4373                  */
4374                 overhead = le32_to_cpu(es->s_first_data_block);
4375
4376                 /*
4377                  * Add the overhead attributed to the superblock and
4378                  * block group descriptors.  If the sparse superblocks
4379                  * feature is turned on, then not all groups have this.
4380                  */
4381                 for (i = 0; i < ngroups; i++) {
4382                         overhead += ext4_bg_has_super(sb, i) +
4383                                 ext4_bg_num_gdb(sb, i);
4384                         cond_resched();
4385                 }
4386
4387                 /*
4388                  * Every block group has an inode bitmap, a block
4389                  * bitmap, and an inode table.
4390                  */
4391                 overhead += ngroups * (2 + sbi->s_itb_per_group);
4392                 sbi->s_overhead_last = overhead;
4393                 smp_wmb();
4394                 sbi->s_blocks_last = ext4_blocks_count(es);
4395         }
4396
4397         buf->f_type = EXT4_SUPER_MAGIC;
4398         buf->f_bsize = sb->s_blocksize;
4399         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
4400         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
4401                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
4402         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
4403         if (buf->f_bfree < ext4_r_blocks_count(es))
4404                 buf->f_bavail = 0;
4405         buf->f_files = le32_to_cpu(es->s_inodes_count);
4406         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4407         buf->f_namelen = EXT4_NAME_LEN;
4408         fsid = le64_to_cpup((void *)es->s_uuid) ^
4409                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4410         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4411         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4412
4413         return 0;
4414 }
4415
4416 /* Helper function for writing quotas on sync - we need to start transaction
4417  * before quota file is locked for write. Otherwise the are possible deadlocks:
4418  * Process 1                         Process 2
4419  * ext4_create()                     quota_sync()
4420  *   jbd2_journal_start()                  write_dquot()
4421  *   dquot_initialize()                         down(dqio_mutex)
4422  *     down(dqio_mutex)                    jbd2_journal_start()
4423  *
4424  */
4425
4426 #ifdef CONFIG_QUOTA
4427
4428 static inline struct inode *dquot_to_inode(struct dquot *dquot)
4429 {
4430         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
4431 }
4432
4433 static int ext4_write_dquot(struct dquot *dquot)
4434 {
4435         int ret, err;
4436         handle_t *handle;
4437         struct inode *inode;
4438
4439         inode = dquot_to_inode(dquot);
4440         handle = ext4_journal_start(inode,
4441                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4442         if (IS_ERR(handle))
4443                 return PTR_ERR(handle);
4444         ret = dquot_commit(dquot);
4445         err = ext4_journal_stop(handle);
4446         if (!ret)
4447                 ret = err;
4448         return ret;
4449 }
4450
4451 static int ext4_acquire_dquot(struct dquot *dquot)
4452 {
4453         int ret, err;
4454         handle_t *handle;
4455
4456         handle = ext4_journal_start(dquot_to_inode(dquot),
4457                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4458         if (IS_ERR(handle))
4459                 return PTR_ERR(handle);
4460         ret = dquot_acquire(dquot);
4461         err = ext4_journal_stop(handle);
4462         if (!ret)
4463                 ret = err;
4464         return ret;
4465 }
4466
4467 static int ext4_release_dquot(struct dquot *dquot)
4468 {
4469         int ret, err;
4470         handle_t *handle;
4471
4472         handle = ext4_journal_start(dquot_to_inode(dquot),
4473                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4474         if (IS_ERR(handle)) {
4475                 /* Release dquot anyway to avoid endless cycle in dqput() */
4476                 dquot_release(dquot);
4477                 return PTR_ERR(handle);
4478         }
4479         ret = dquot_release(dquot);
4480         err = ext4_journal_stop(handle);
4481         if (!ret)
4482                 ret = err;
4483         return ret;
4484 }
4485
4486 static int ext4_mark_dquot_dirty(struct dquot *dquot)
4487 {
4488         /* Are we journaling quotas? */
4489         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
4490             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
4491                 dquot_mark_dquot_dirty(dquot);
4492                 return ext4_write_dquot(dquot);
4493         } else {
4494                 return dquot_mark_dquot_dirty(dquot);
4495         }
4496 }
4497
4498 static int ext4_write_info(struct super_block *sb, int type)
4499 {
4500         int ret, err;
4501         handle_t *handle;
4502
4503         /* Data block + inode block */
4504         handle = ext4_journal_start(sb->s_root->d_inode, 2);
4505         if (IS_ERR(handle))
4506                 return PTR_ERR(handle);
4507         ret = dquot_commit_info(sb, type);
4508         err = ext4_journal_stop(handle);
4509         if (!ret)
4510                 ret = err;
4511         return ret;
4512 }
4513
4514 /*
4515  * Turn on quotas during mount time - we need to find
4516  * the quota file and such...
4517  */
4518 static int ext4_quota_on_mount(struct super_block *sb, int type)
4519 {
4520         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4521                                         EXT4_SB(sb)->s_jquota_fmt, type);
4522 }
4523
4524 /*
4525  * Standard function to be called on quota_on
4526  */
4527 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4528                          char *name)
4529 {
4530         int err;
4531         struct path path;
4532
4533         if (!test_opt(sb, QUOTA))
4534                 return -EINVAL;
4535
4536         err = kern_path(name, LOOKUP_FOLLOW, &path);
4537         if (err)
4538                 return err;
4539
4540         /* Quotafile not on the same filesystem? */
4541         if (path.mnt->mnt_sb != sb) {
4542                 path_put(&path);
4543                 return -EXDEV;
4544         }
4545         /* Journaling quota? */
4546         if (EXT4_SB(sb)->s_qf_names[type]) {
4547                 /* Quotafile not in fs root? */
4548                 if (path.dentry->d_parent != sb->s_root)
4549                         ext4_msg(sb, KERN_WARNING,
4550                                 "Quota file not on filesystem root. "
4551                                 "Journaled quota will not work");
4552         }
4553
4554         /*
4555          * When we journal data on quota file, we have to flush journal to see
4556          * all updates to the file when we bypass pagecache...
4557          */
4558         if (EXT4_SB(sb)->s_journal &&
4559             ext4_should_journal_data(path.dentry->d_inode)) {
4560                 /*
4561                  * We don't need to lock updates but journal_flush() could
4562                  * otherwise be livelocked...
4563                  */
4564                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4565                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4566                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4567                 if (err) {
4568                         path_put(&path);
4569                         return err;
4570                 }
4571         }
4572
4573         err = dquot_quota_on_path(sb, type, format_id, &path);
4574         path_put(&path);
4575         return err;
4576 }
4577
4578 static int ext4_quota_off(struct super_block *sb, int type)
4579 {
4580         /* Force all delayed allocation blocks to be allocated.
4581          * Caller already holds s_umount sem */
4582         if (test_opt(sb, DELALLOC))
4583                 sync_filesystem(sb);
4584
4585         return dquot_quota_off(sb, type);
4586 }
4587
4588 /* Read data from quotafile - avoid pagecache and such because we cannot afford
4589  * acquiring the locks... As quota files are never truncated and quota code
4590  * itself serializes the operations (and noone else should touch the files)
4591  * we don't have to be afraid of races */
4592 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
4593                                size_t len, loff_t off)
4594 {
4595         struct inode *inode = sb_dqopt(sb)->files[type];
4596         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4597         int err = 0;
4598         int offset = off & (sb->s_blocksize - 1);
4599         int tocopy;
4600         size_t toread;
4601         struct buffer_head *bh;
4602         loff_t i_size = i_size_read(inode);
4603
4604         if (off > i_size)
4605                 return 0;
4606         if (off+len > i_size)
4607                 len = i_size-off;
4608         toread = len;
4609         while (toread > 0) {
4610                 tocopy = sb->s_blocksize - offset < toread ?
4611                                 sb->s_blocksize - offset : toread;
4612                 bh = ext4_bread(NULL, inode, blk, 0, &err);
4613                 if (err)
4614                         return err;
4615                 if (!bh)        /* A hole? */
4616                         memset(data, 0, tocopy);
4617                 else
4618                         memcpy(data, bh->b_data+offset, tocopy);
4619                 brelse(bh);
4620                 offset = 0;
4621                 toread -= tocopy;
4622                 data += tocopy;
4623                 blk++;
4624         }
4625         return len;
4626 }
4627
4628 /* Write to quotafile (we know the transaction is already started and has
4629  * enough credits) */
4630 static ssize_t ext4_quota_write(struct super_block *sb, int type,
4631                                 const char *data, size_t len, loff_t off)
4632 {
4633         struct inode *inode = sb_dqopt(sb)->files[type];
4634         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4635         int err = 0;
4636         int offset = off & (sb->s_blocksize - 1);
4637         struct buffer_head *bh;
4638         handle_t *handle = journal_current_handle();
4639
4640         if (EXT4_SB(sb)->s_journal && !handle) {
4641                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4642                         " cancelled because transaction is not started",
4643                         (unsigned long long)off, (unsigned long long)len);
4644                 return -EIO;
4645         }
4646         /*
4647          * Since we account only one data block in transaction credits,
4648          * then it is impossible to cross a block boundary.
4649          */
4650         if (sb->s_blocksize - offset < len) {
4651                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4652                         " cancelled because not block aligned",
4653                         (unsigned long long)off, (unsigned long long)len);
4654                 return -EIO;
4655         }
4656
4657         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
4658         bh = ext4_bread(handle, inode, blk, 1, &err);
4659         if (!bh)
4660                 goto out;
4661         err = ext4_journal_get_write_access(handle, bh);
4662         if (err) {
4663                 brelse(bh);
4664                 goto out;
4665         }
4666         lock_buffer(bh);
4667         memcpy(bh->b_data+offset, data, len);
4668         flush_dcache_page(bh->b_page);
4669         unlock_buffer(bh);
4670         err = ext4_handle_dirty_metadata(handle, NULL, bh);
4671         brelse(bh);
4672 out:
4673         if (err) {
4674                 mutex_unlock(&inode->i_mutex);
4675                 return err;
4676         }
4677         if (inode->i_size < off + len) {
4678                 i_size_write(inode, off + len);
4679                 EXT4_I(inode)->i_disksize = inode->i_size;
4680         }
4681         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
4682         ext4_mark_inode_dirty(handle, inode);
4683         mutex_unlock(&inode->i_mutex);
4684         return len;
4685 }
4686
4687 #endif
4688
4689 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
4690                        const char *dev_name, void *data)
4691 {
4692         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
4693 }
4694
4695 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4696 static struct file_system_type ext2_fs_type = {
4697         .owner          = THIS_MODULE,
4698         .name           = "ext2",
4699         .mount          = ext4_mount,
4700         .kill_sb        = kill_block_super,
4701         .fs_flags       = FS_REQUIRES_DEV,
4702 };
4703
4704 static inline void register_as_ext2(void)
4705 {
4706         int err = register_filesystem(&ext2_fs_type);
4707         if (err)
4708                 printk(KERN_WARNING
4709                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
4710 }
4711
4712 static inline void unregister_as_ext2(void)
4713 {
4714         unregister_filesystem(&ext2_fs_type);
4715 }
4716 MODULE_ALIAS("ext2");
4717 #else
4718 static inline void register_as_ext2(void) { }
4719 static inline void unregister_as_ext2(void) { }
4720 #endif
4721
4722 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4723 static inline void register_as_ext3(void)
4724 {
4725         int err = register_filesystem(&ext3_fs_type);
4726         if (err)
4727                 printk(KERN_WARNING
4728                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
4729 }
4730
4731 static inline void unregister_as_ext3(void)
4732 {
4733         unregister_filesystem(&ext3_fs_type);
4734 }
4735 MODULE_ALIAS("ext3");
4736 #else
4737 static inline void register_as_ext3(void) { }
4738 static inline void unregister_as_ext3(void) { }
4739 #endif
4740
4741 static struct file_system_type ext4_fs_type = {
4742         .owner          = THIS_MODULE,
4743         .name           = "ext4",
4744         .mount          = ext4_mount,
4745         .kill_sb        = kill_block_super,
4746         .fs_flags       = FS_REQUIRES_DEV,
4747 };
4748
4749 int __init ext4_init_feat_adverts(void)
4750 {
4751         struct ext4_features *ef;
4752         int ret = -ENOMEM;
4753
4754         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
4755         if (!ef)
4756                 goto out;
4757
4758         ef->f_kobj.kset = ext4_kset;
4759         init_completion(&ef->f_kobj_unregister);
4760         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
4761                                    "features");
4762         if (ret) {
4763                 kfree(ef);
4764                 goto out;
4765         }
4766
4767         ext4_feat = ef;
4768         ret = 0;
4769 out:
4770         return ret;
4771 }
4772
4773 static int __init ext4_init_fs(void)
4774 {
4775         int err;
4776
4777         ext4_check_flag_values();
4778         err = ext4_init_pageio();
4779         if (err)
4780                 return err;
4781         err = ext4_init_system_zone();
4782         if (err)
4783                 goto out5;
4784         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
4785         if (!ext4_kset)
4786                 goto out4;
4787         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
4788
4789         err = ext4_init_feat_adverts();
4790
4791         err = ext4_init_mballoc();
4792         if (err)
4793                 goto out3;
4794
4795         err = ext4_init_xattr();
4796         if (err)
4797                 goto out2;
4798         err = init_inodecache();
4799         if (err)
4800                 goto out1;
4801         register_as_ext2();
4802         register_as_ext3();
4803         err = register_filesystem(&ext4_fs_type);
4804         if (err)
4805                 goto out;
4806
4807         ext4_li_info = NULL;
4808         mutex_init(&ext4_li_mtx);
4809         return 0;
4810 out:
4811         unregister_as_ext2();
4812         unregister_as_ext3();
4813         destroy_inodecache();
4814 out1:
4815         ext4_exit_xattr();
4816 out2:
4817         ext4_exit_mballoc();
4818 out3:
4819         kfree(ext4_feat);
4820         remove_proc_entry("fs/ext4", NULL);
4821         kset_unregister(ext4_kset);
4822 out4:
4823         ext4_exit_system_zone();
4824 out5:
4825         ext4_exit_pageio();
4826         return err;
4827 }
4828
4829 static void __exit ext4_exit_fs(void)
4830 {
4831         ext4_destroy_lazyinit_thread();
4832         unregister_as_ext2();
4833         unregister_as_ext3();
4834         unregister_filesystem(&ext4_fs_type);
4835         destroy_inodecache();
4836         ext4_exit_xattr();
4837         ext4_exit_mballoc();
4838         remove_proc_entry("fs/ext4", NULL);
4839         kset_unregister(ext4_kset);
4840         ext4_exit_system_zone();
4841         ext4_exit_pageio();
4842 }
4843
4844 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
4845 MODULE_DESCRIPTION("Fourth Extended Filesystem");
4846 MODULE_LICENSE("GPL");
4847 module_init(ext4_init_fs)
4848 module_exit(ext4_exit_fs)