fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/jbd2.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/parser.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/cleancache.h>
  42 #include <asm/uaccess.h>
  43
  44 #include <linux/kthread.h>
  45 #include <linux/freezer.h>
  46
  47 #include "ext4.h"
  48 #include "ext4_extents.h"
  49 #include "ext4_jbd2.h"
  50 #include "xattr.h"
  51 #include "acl.h"
  52 #include "mballoc.h"
  53
  54 #define CREATE_TRACE_POINTS
  55 #include <trace/events/ext4.h>
  56
  57 static struct proc_dir_entry *ext4_proc_root;
  58 static struct kset *ext4_kset;
  59 static struct ext4_lazy_init *ext4_li_info;
  60 static struct mutex ext4_li_mtx;
  61 static struct ext4_features *ext4_feat;
  62
  63 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  64                              unsigned long journal_devnum);
  65 static int ext4_commit_super(struct super_block *sb, int sync);
  66 static void ext4_mark_recovery_complete(struct super_block *sb,
  67                                         struct ext4_super_block *es);
  68 static void ext4_clear_journal_err(struct super_block *sb,
  69                                    struct ext4_super_block *es);
  70 static int ext4_sync_fs(struct super_block *sb, int wait);
  71 static const char *ext4_decode_error(struct super_block *sb, int errno,
  72                                      char nbuf[16]);
  73 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  74 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  75 static int ext4_unfreeze(struct super_block *sb);
  76 static void ext4_write_super(struct super_block *sb);
  77 static int ext4_freeze(struct super_block *sb);
  78 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  79                        const char *dev_name, void *data);
  80 static inline int ext2_feature_set_ok(struct super_block *sb);
  81 static inline int ext3_feature_set_ok(struct super_block *sb);
  82 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  83 static void ext4_destroy_lazyinit_thread(void);
  84 static void ext4_unregister_li_request(struct super_block *sb);
  85 static void ext4_clear_request_list(void);
  86
  87 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
  88 static struct file_system_type ext2_fs_type = {
  89         .owner          = THIS_MODULE,
  90         .name           = "ext2",
  91         .mount          = ext4_mount,
  92         .kill_sb        = kill_block_super,
  93         .fs_flags       = FS_REQUIRES_DEV,
  94 };
  95 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
  96 #else
  97 #define IS_EXT2_SB(sb) (0)
  98 #endif
  99
 100
 101 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
 102 static struct file_system_type ext3_fs_type = {
 103         .owner          = THIS_MODULE,
 104         .name           = "ext3",
 105         .mount          = ext4_mount,
 106         .kill_sb        = kill_block_super,
 107         .fs_flags       = FS_REQUIRES_DEV,
 108 };
 109 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 110 #else
 111 #define IS_EXT3_SB(sb) (0)
 112 #endif
 113
 114 void *ext4_kvmalloc(size_t size, gfp_t flags)
 115 {
 116         void *ret;
 117
 118         ret = kmalloc(size, flags);
 119         if (!ret)
 120                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 121         return ret;
 122 }
 123
 124 void *ext4_kvzalloc(size_t size, gfp_t flags)
 125 {
 126         void *ret;
 127
 128         ret = kzalloc(size, flags);
 129         if (!ret)
 130                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 131         return ret;
 132 }
 133
 134 void ext4_kvfree(void *ptr)
 135 {
 136         if (is_vmalloc_addr(ptr))
 137                 vfree(ptr);
 138         else
 139                 kfree(ptr);
 140
 141 }
 142
 143 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 144                                struct ext4_group_desc *bg)
 145 {
 146         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 147                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 148                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 149 }
 150
 151 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 152                                struct ext4_group_desc *bg)
 153 {
 154         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 155                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 156                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 157 }
 158
 159 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 160                               struct ext4_group_desc *bg)
 161 {
 162         return le32_to_cpu(bg->bg_inode_table_lo) |
 163                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 164                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 165 }
 166
 167 __u32 ext4_free_group_clusters(struct super_block *sb,
 168                                struct ext4_group_desc *bg)
 169 {
 170         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 171                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 172                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 173 }
 174
 175 __u32 ext4_free_inodes_count(struct super_block *sb,
 176                               struct ext4_group_desc *bg)
 177 {
 178         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 179                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 180                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 181 }
 182
 183 __u32 ext4_used_dirs_count(struct super_block *sb,
 184                               struct ext4_group_desc *bg)
 185 {
 186         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 187                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 188                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 189 }
 190
 191 __u32 ext4_itable_unused_count(struct super_block *sb,
 192                               struct ext4_group_desc *bg)
 193 {
 194         return le16_to_cpu(bg->bg_itable_unused_lo) |
 195                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 196                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 197 }
 198
 199 void ext4_block_bitmap_set(struct super_block *sb,
 200                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 201 {
 202         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 203         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 204                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 205 }
 206
 207 void ext4_inode_bitmap_set(struct super_block *sb,
 208                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 209 {
 210         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 211         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 212                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 213 }
 214
 215 void ext4_inode_table_set(struct super_block *sb,
 216                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 217 {
 218         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 219         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 220                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 221 }
 222
 223 void ext4_free_group_clusters_set(struct super_block *sb,
 224                                   struct ext4_group_desc *bg, __u32 count)
 225 {
 226         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 227         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 228                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 229 }
 230
 231 void ext4_free_inodes_set(struct super_block *sb,
 232                           struct ext4_group_desc *bg, __u32 count)
 233 {
 234         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 235         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 236                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 237 }
 238
 239 void ext4_used_dirs_set(struct super_block *sb,
 240                           struct ext4_group_desc *bg, __u32 count)
 241 {
 242         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 243         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 244                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 245 }
 246
 247 void ext4_itable_unused_set(struct super_block *sb,
 248                           struct ext4_group_desc *bg, __u32 count)
 249 {
 250         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 251         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 252                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 253 }
 254
 255
 256 /* Just increment the non-pointer handle value */
 257 static handle_t *ext4_get_nojournal(void)
 258 {
 259         handle_t *handle = current->journal_info;
 260         unsigned long ref_cnt = (unsigned long)handle;
 261
 262         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
 263
 264         ref_cnt++;
 265         handle = (handle_t *)ref_cnt;
 266
 267         current->journal_info = handle;
 268         return handle;
 269 }
 270
 271
 272 /* Decrement the non-pointer handle value */
 273 static void ext4_put_nojournal(handle_t *handle)
 274 {
 275         unsigned long ref_cnt = (unsigned long)handle;
 276
 277         BUG_ON(ref_cnt == 0);
 278
 279         ref_cnt--;
 280         handle = (handle_t *)ref_cnt;
 281
 282         current->journal_info = handle;
 283 }
 284
 285 /*
 286  * Wrappers for jbd2_journal_start/end.
 287  *
 288  * The only special thing we need to do here is to make sure that all
 289  * journal_end calls result in the superblock being marked dirty, so
 290  * that sync() will call the filesystem's write_super callback if
 291  * appropriate.
 292  *
 293  * To avoid j_barrier hold in userspace when a user calls freeze(),
 294  * ext4 prevents a new handle from being started by s_frozen, which
 295  * is in an upper layer.
 296  */
 297 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 298 {
 299         journal_t *journal;
 300         handle_t  *handle;
 301
 302         trace_ext4_journal_start(sb, nblocks, _RET_IP_);
 303         if (sb->s_flags & MS_RDONLY)
 304                 return ERR_PTR(-EROFS);
 305
 306         journal = EXT4_SB(sb)->s_journal;
 307         handle = ext4_journal_current_handle();
 308
 309         /*
 310          * If a handle has been started, it should be allowed to
 311          * finish, otherwise deadlock could happen between freeze
 312          * and others(e.g. truncate) due to the restart of the
 313          * journal handle if the filesystem is forzen and active
 314          * handles are not stopped.
 315          */
 316         if (!handle)
 317                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
 318
 319         if (!journal)
 320                 return ext4_get_nojournal();
 321         /*
 322          * Special case here: if the journal has aborted behind our
 323          * backs (eg. EIO in the commit thread), then we still need to
 324          * take the FS itself readonly cleanly.
 325          */
 326         if (is_journal_aborted(journal)) {
 327                 ext4_abort(sb, "Detected aborted journal");
 328                 return ERR_PTR(-EROFS);
 329         }
 330         return jbd2_journal_start(journal, nblocks);
 331 }
 332
 333 /*
 334  * The only special thing we need to do here is to make sure that all
 335  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 336  * that sync() will call the filesystem's write_super callback if
 337  * appropriate.
 338  */
 339 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
 340 {
 341         struct super_block *sb;
 342         int err;
 343         int rc;
 344
 345         if (!ext4_handle_valid(handle)) {
 346                 ext4_put_nojournal(handle);
 347                 return 0;
 348         }
 349         sb = handle->h_transaction->t_journal->j_private;
 350         err = handle->h_err;
 351         rc = jbd2_journal_stop(handle);
 352
 353         if (!err)
 354                 err = rc;
 355         if (err)
 356                 __ext4_std_error(sb, where, line, err);
 357         return err;
 358 }
 359
 360 void ext4_journal_abort_handle(const char *caller, unsigned int line,
 361                                const char *err_fn, struct buffer_head *bh,
 362                                handle_t *handle, int err)
 363 {
 364         char nbuf[16];
 365         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 366
 367         BUG_ON(!ext4_handle_valid(handle));
 368
 369         if (bh)
 370                 BUFFER_TRACE(bh, "abort");
 371
 372         if (!handle->h_err)
 373                 handle->h_err = err;
 374
 375         if (is_handle_aborted(handle))
 376                 return;
 377
 378         printk(KERN_ERR "%s:%d: aborting transaction: %s in %s\n",
 379                caller, line, errstr, err_fn);
 380
 381         jbd2_journal_abort_handle(handle);
 382 }
 383
 384 static void __save_error_info(struct super_block *sb, const char *func,
 385                             unsigned int line)
 386 {
 387         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 388
 389         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 390         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 391         es->s_last_error_time = cpu_to_le32(get_seconds());
 392         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 393         es->s_last_error_line = cpu_to_le32(line);
 394         if (!es->s_first_error_time) {
 395                 es->s_first_error_time = es->s_last_error_time;
 396                 strncpy(es->s_first_error_func, func,
 397                         sizeof(es->s_first_error_func));
 398                 es->s_first_error_line = cpu_to_le32(line);
 399                 es->s_first_error_ino = es->s_last_error_ino;
 400                 es->s_first_error_block = es->s_last_error_block;
 401         }
 402         /*
 403          * Start the daily error reporting function if it hasn't been
 404          * started already
 405          */
 406         if (!es->s_error_count)
 407                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 408         es->s_error_count = cpu_to_le32(le32_to_cpu(es->s_error_count) + 1);
 409 }
 410
 411 static void save_error_info(struct super_block *sb, const char *func,
 412                             unsigned int line)
 413 {
 414         __save_error_info(sb, func, line);
 415         ext4_commit_super(sb, 1);
 416 }
 417
 418 /*
 419  * The del_gendisk() function uninitializes the disk-specific data
 420  * structures, including the bdi structure, without telling anyone
 421  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 422  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 423  * This is a kludge to prevent these oops until we can put in a proper
 424  * hook in del_gendisk() to inform the VFS and file system layers.
 425  */
 426 static int block_device_ejected(struct super_block *sb)
 427 {
 428         struct inode *bd_inode = sb->s_bdev->bd_inode;
 429         struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info;
 430
 431         return bdi->dev == NULL;
 432 }
 433
 434
 435 /* Deal with the reporting of failure conditions on a filesystem such as
 436  * inconsistencies detected or read IO failures.
 437  *
 438  * On ext2, we can store the error state of the filesystem in the
 439  * superblock.  That is not possible on ext4, because we may have other
 440  * write ordering constraints on the superblock which prevent us from
 441  * writing it out straight away; and given that the journal is about to
 442  * be aborted, we can't rely on the current, or future, transactions to
 443  * write out the superblock safely.
 444  *
 445  * We'll just use the jbd2_journal_abort() error code to record an error in
 446  * the journal instead.  On recovery, the journal will complain about
 447  * that error until we've noted it down and cleared it.
 448  */
 449
 450 static void ext4_handle_error(struct super_block *sb)
 451 {
 452         if (sb->s_flags & MS_RDONLY)
 453                 return;
 454
 455         if (!test_opt(sb, ERRORS_CONT)) {
 456                 journal_t *journal = EXT4_SB(sb)->s_journal;
 457
 458                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 459                 if (journal)
 460                         jbd2_journal_abort(journal, -EIO);
 461         }
 462         if (test_opt(sb, ERRORS_RO)) {
 463                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 464                 sb->s_flags |= MS_RDONLY;
 465         }
 466         if (test_opt(sb, ERRORS_PANIC))
 467                 panic("EXT4-fs (device %s): panic forced after error\n",
 468                         sb->s_id);
 469 }
 470
 471 void __ext4_error(struct super_block *sb, const char *function,
 472                   unsigned int line, const char *fmt, ...)
 473 {
 474         struct va_format vaf;
 475         va_list args;
 476
 477         va_start(args, fmt);
 478         vaf.fmt = fmt;
 479         vaf.va = &args;
 480         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 481                sb->s_id, function, line, current->comm, &vaf);
 482         va_end(args);
 483         save_error_info(sb, function, line);
 484
 485         ext4_handle_error(sb);
 486 }
 487
 488 void ext4_error_inode(struct inode *inode, const char *function,
 489                       unsigned int line, ext4_fsblk_t block,
 490                       const char *fmt, ...)
 491 {
 492         va_list args;
 493         struct va_format vaf;
 494         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 495
 496         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 497         es->s_last_error_block = cpu_to_le64(block);
 498         save_error_info(inode->i_sb, function, line);
 499         va_start(args, fmt);
 500         vaf.fmt = fmt;
 501         vaf.va = &args;
 502         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: inode #%lu: ",
 503                inode->i_sb->s_id, function, line, inode->i_ino);
 504         if (block)
 505                 printk(KERN_CONT "block %llu: ", block);
 506         printk(KERN_CONT "comm %s: %pV\n", current->comm, &vaf);
 507         va_end(args);
 508
 509         ext4_handle_error(inode->i_sb);
 510 }
 511
 512 void ext4_error_file(struct file *file, const char *function,
 513                      unsigned int line, ext4_fsblk_t block,
 514                      const char *fmt, ...)
 515 {
 516         va_list args;
 517         struct va_format vaf;
 518         struct ext4_super_block *es;
 519         struct inode *inode = file->f_dentry->d_inode;
 520         char pathname[80], *path;
 521
 522         es = EXT4_SB(inode->i_sb)->s_es;
 523         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 524         save_error_info(inode->i_sb, function, line);
 525         path = d_path(&(file->f_path), pathname, sizeof(pathname));
 526         if (IS_ERR(path))
 527                 path = "(unknown)";
 528         printk(KERN_CRIT
 529                "EXT4-fs error (device %s): %s:%d: inode #%lu: ",
 530                inode->i_sb->s_id, function, line, inode->i_ino);
 531         if (block)
 532                 printk(KERN_CONT "block %llu: ", block);
 533         va_start(args, fmt);
 534         vaf.fmt = fmt;
 535         vaf.va = &args;
 536         printk(KERN_CONT "comm %s: path %s: %pV\n", current->comm, path, &vaf);
 537         va_end(args);
 538
 539         ext4_handle_error(inode->i_sb);
 540 }
 541
 542 static const char *ext4_decode_error(struct super_block *sb, int errno,
 543                                      char nbuf[16])
 544 {
 545         char *errstr = NULL;
 546
 547         switch (errno) {
 548         case -EIO:
 549                 errstr = "IO failure";
 550                 break;
 551         case -ENOMEM:
 552                 errstr = "Out of memory";
 553                 break;
 554         case -EROFS:
 555                 if (!sb || (EXT4_SB(sb)->s_journal &&
 556                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 557                         errstr = "Journal has aborted";
 558                 else
 559                         errstr = "Readonly filesystem";
 560                 break;
 561         default:
 562                 /* If the caller passed in an extra buffer for unknown
 563                  * errors, textualise them now.  Else we just return
 564                  * NULL. */
 565                 if (nbuf) {
 566                         /* Check for truncated error codes... */
 567                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 568                                 errstr = nbuf;
 569                 }
 570                 break;
 571         }
 572
 573         return errstr;
 574 }
 575
 576 /* __ext4_std_error decodes expected errors from journaling functions
 577  * automatically and invokes the appropriate error response.  */
 578
 579 void __ext4_std_error(struct super_block *sb, const char *function,
 580                       unsigned int line, int errno)
 581 {
 582         char nbuf[16];
 583         const char *errstr;
 584
 585         /* Special case: if the error is EROFS, and we're not already
 586          * inside a transaction, then there's really no point in logging
 587          * an error. */
 588         if (errno == -EROFS && journal_current_handle() == NULL &&
 589             (sb->s_flags & MS_RDONLY))
 590                 return;
 591
 592         errstr = ext4_decode_error(sb, errno, nbuf);
 593         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 594                sb->s_id, function, line, errstr);
 595         save_error_info(sb, function, line);
 596
 597         ext4_handle_error(sb);
 598 }
 599
 600 /*
 601  * ext4_abort is a much stronger failure handler than ext4_error.  The
 602  * abort function may be used to deal with unrecoverable failures such
 603  * as journal IO errors or ENOMEM at a critical moment in log management.
 604  *
 605  * We unconditionally force the filesystem into an ABORT|READONLY state,
 606  * unless the error response on the fs has been set to panic in which
 607  * case we take the easy way out and panic immediately.
 608  */
 609
 610 void __ext4_abort(struct super_block *sb, const char *function,
 611                 unsigned int line, const char *fmt, ...)
 612 {
 613         va_list args;
 614
 615         save_error_info(sb, function, line);
 616         va_start(args, fmt);
 617         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 618                function, line);
 619         vprintk(fmt, args);
 620         printk("\n");
 621         va_end(args);
 622
 623         if ((sb->s_flags & MS_RDONLY) == 0) {
 624                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 625                 sb->s_flags |= MS_RDONLY;
 626                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 627                 if (EXT4_SB(sb)->s_journal)
 628                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 629                 save_error_info(sb, function, line);
 630         }
 631         if (test_opt(sb, ERRORS_PANIC))
 632                 panic("EXT4-fs panic from previous error\n");
 633 }
 634
 635 void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
 636 {
 637         struct va_format vaf;
 638         va_list args;
 639
 640         va_start(args, fmt);
 641         vaf.fmt = fmt;
 642         vaf.va = &args;
 643         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 644         va_end(args);
 645 }
 646
 647 void __ext4_warning(struct super_block *sb, const char *function,
 648                     unsigned int line, const char *fmt, ...)
 649 {
 650         struct va_format vaf;
 651         va_list args;
 652
 653         va_start(args, fmt);
 654         vaf.fmt = fmt;
 655         vaf.va = &args;
 656         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 657                sb->s_id, function, line, &vaf);
 658         va_end(args);
 659 }
 660
 661 void __ext4_grp_locked_error(const char *function, unsigned int line,
 662                              struct super_block *sb, ext4_group_t grp,
 663                              unsigned long ino, ext4_fsblk_t block,
 664                              const char *fmt, ...)
 665 __releases(bitlock)
 666 __acquires(bitlock)
 667 {
 668         struct va_format vaf;
 669         va_list args;
 670         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 671
 672         es->s_last_error_ino = cpu_to_le32(ino);
 673         es->s_last_error_block = cpu_to_le64(block);
 674         __save_error_info(sb, function, line);
 675
 676         va_start(args, fmt);
 677
 678         vaf.fmt = fmt;
 679         vaf.va = &args;
 680         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 681                sb->s_id, function, line, grp);
 682         if (ino)
 683                 printk(KERN_CONT "inode %lu: ", ino);
 684         if (block)
 685                 printk(KERN_CONT "block %llu:", (unsigned long long) block);
 686         printk(KERN_CONT "%pV\n", &vaf);
 687         va_end(args);
 688
 689         if (test_opt(sb, ERRORS_CONT)) {
 690                 ext4_commit_super(sb, 0);
 691                 return;
 692         }
 693
 694         ext4_unlock_group(sb, grp);
 695         ext4_handle_error(sb);
 696         /*
 697          * We only get here in the ERRORS_RO case; relocking the group
 698          * may be dangerous, but nothing bad will happen since the
 699          * filesystem will have already been marked read/only and the
 700          * journal has been aborted.  We return 1 as a hint to callers
 701          * who might what to use the return value from
 702          * ext4_grp_locked_error() to distinguish between the
 703          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 704          * aggressively from the ext4 function in question, with a
 705          * more appropriate error code.
 706          */
 707         ext4_lock_group(sb, grp);
 708         return;
 709 }
 710
 711 void ext4_update_dynamic_rev(struct super_block *sb)
 712 {
 713         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 714
 715         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 716                 return;
 717
 718         ext4_warning(sb,
 719                      "updating to rev %d because of new feature flag, "
 720                      "running e2fsck is recommended",
 721                      EXT4_DYNAMIC_REV);
 722
 723         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 724         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 725         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 726         /* leave es->s_feature_*compat flags alone */
 727         /* es->s_uuid will be set by e2fsck if empty */
 728
 729         /*
 730          * The rest of the superblock fields should be zero, and if not it
 731          * means they are likely already in use, so leave them alone.  We
 732          * can leave it up to e2fsck to clean up any inconsistencies there.
 733          */
 734 }
 735
 736 /*
 737  * Open the external journal device
 738  */
 739 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 740 {
 741         struct block_device *bdev;
 742         char b[BDEVNAME_SIZE];
 743
 744         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 745         if (IS_ERR(bdev))
 746                 goto fail;
 747         return bdev;
 748
 749 fail:
 750         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 751                         __bdevname(dev, b), PTR_ERR(bdev));
 752         return NULL;
 753 }
 754
 755 /*
 756  * Release the journal device
 757  */
 758 static int ext4_blkdev_put(struct block_device *bdev)
 759 {
 760         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 761 }
 762
 763 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 764 {
 765         struct block_device *bdev;
 766         int ret = -ENODEV;
 767
 768         bdev = sbi->journal_bdev;
 769         if (bdev) {
 770                 ret = ext4_blkdev_put(bdev);
 771                 sbi->journal_bdev = NULL;
 772         }
 773         return ret;
 774 }
 775
 776 static inline struct inode *orphan_list_entry(struct list_head *l)
 777 {
 778         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 779 }
 780
 781 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 782 {
 783         struct list_head *l;
 784
 785         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 786                  le32_to_cpu(sbi->s_es->s_last_orphan));
 787
 788         printk(KERN_ERR "sb_info orphan list:\n");
 789         list_for_each(l, &sbi->s_orphan) {
 790                 struct inode *inode = orphan_list_entry(l);
 791                 printk(KERN_ERR "  "
 792                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 793                        inode->i_sb->s_id, inode->i_ino, inode,
 794                        inode->i_mode, inode->i_nlink,
 795                        NEXT_ORPHAN(inode));
 796         }
 797 }
 798
 799 static void ext4_put_super(struct super_block *sb)
 800 {
 801         struct ext4_sb_info *sbi = EXT4_SB(sb);
 802         struct ext4_super_block *es = sbi->s_es;
 803         int i, err;
 804
 805         ext4_unregister_li_request(sb);
 806         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 807
 808         flush_workqueue(sbi->dio_unwritten_wq);
 809         destroy_workqueue(sbi->dio_unwritten_wq);
 810
 811         lock_super(sb);
 812         if (sb->s_dirt)
 813                 ext4_commit_super(sb, 1);
 814
 815         if (sbi->s_journal) {
 816                 err = jbd2_journal_destroy(sbi->s_journal);
 817                 sbi->s_journal = NULL;
 818                 if (err < 0)
 819                         ext4_abort(sb, "Couldn't clean up the journal");
 820         }
 821
 822         del_timer_sync(&sbi->s_err_report);
 823         ext4_release_system_zone(sb);
 824         ext4_mb_release(sb);
 825         ext4_ext_release(sb);
 826         ext4_xattr_put_super(sb);
 827
 828         if (!(sb->s_flags & MS_RDONLY)) {
 829                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 830                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 831                 ext4_commit_super(sb, 1);
 832         }
 833         if (sbi->s_proc) {
 834                 remove_proc_entry(sb->s_id, ext4_proc_root);
 835         }
 836         kobject_del(&sbi->s_kobj);
 837
 838         for (i = 0; i < sbi->s_gdb_count; i++)
 839                 brelse(sbi->s_group_desc[i]);
 840         ext4_kvfree(sbi->s_group_desc);
 841         ext4_kvfree(sbi->s_flex_groups);
 842         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 843         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 844         percpu_counter_destroy(&sbi->s_dirs_counter);
 845         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 846         brelse(sbi->s_sbh);
 847 #ifdef CONFIG_QUOTA
 848         for (i = 0; i < MAXQUOTAS; i++)
 849                 kfree(sbi->s_qf_names[i]);
 850 #endif
 851
 852         /* Debugging code just in case the in-memory inode orphan list
 853          * isn't empty.  The on-disk one can be non-empty if we've
 854          * detected an error and taken the fs readonly, but the
 855          * in-memory list had better be clean by this point. */
 856         if (!list_empty(&sbi->s_orphan))
 857                 dump_orphan_list(sb, sbi);
 858         J_ASSERT(list_empty(&sbi->s_orphan));
 859
 860         invalidate_bdev(sb->s_bdev);
 861         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 862                 /*
 863                  * Invalidate the journal device's buffers.  We don't want them
 864                  * floating about in memory - the physical journal device may
 865                  * hotswapped, and it breaks the `ro-after' testing code.
 866                  */
 867                 sync_blockdev(sbi->journal_bdev);
 868                 invalidate_bdev(sbi->journal_bdev);
 869                 ext4_blkdev_remove(sbi);
 870         }
 871         if (sbi->s_mmp_tsk)
 872                 kthread_stop(sbi->s_mmp_tsk);
 873         sb->s_fs_info = NULL;
 874         /*
 875          * Now that we are completely done shutting down the
 876          * superblock, we need to actually destroy the kobject.
 877          */
 878         unlock_super(sb);
 879         kobject_put(&sbi->s_kobj);
 880         wait_for_completion(&sbi->s_kobj_unregister);
 881         kfree(sbi->s_blockgroup_lock);
 882         kfree(sbi);
 883 }
 884
 885 static struct kmem_cache *ext4_inode_cachep;
 886
 887 /*
 888  * Called inside transaction, so use GFP_NOFS
 889  */
 890 static struct inode *ext4_alloc_inode(struct super_block *sb)
 891 {
 892         struct ext4_inode_info *ei;
 893
 894         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 895         if (!ei)
 896                 return NULL;
 897
 898         ei->vfs_inode.i_version = 1;
 899         ei->vfs_inode.i_data.writeback_index = 0;
 900         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 901         INIT_LIST_HEAD(&ei->i_prealloc_list);
 902         spin_lock_init(&ei->i_prealloc_lock);
 903         ei->i_reserved_data_blocks = 0;
 904         ei->i_reserved_meta_blocks = 0;
 905         ei->i_allocated_meta_blocks = 0;
 906         ei->i_da_metadata_calc_len = 0;
 907         ei->i_da_metadata_calc_last_lblock = 0;
 908         spin_lock_init(&(ei->i_block_reservation_lock));
 909 #ifdef CONFIG_QUOTA
 910         ei->i_reserved_quota = 0;
 911 #endif
 912         ei->jinode = NULL;
 913         INIT_LIST_HEAD(&ei->i_completed_io_list);
 914         spin_lock_init(&ei->i_completed_io_lock);
 915         ei->cur_aio_dio = NULL;
 916         ei->i_sync_tid = 0;
 917         ei->i_datasync_tid = 0;
 918         atomic_set(&ei->i_ioend_count, 0);
 919         atomic_set(&ei->i_aiodio_unwritten, 0);
 920
 921         return &ei->vfs_inode;
 922 }
 923
 924 static int ext4_drop_inode(struct inode *inode)
 925 {
 926         int drop = generic_drop_inode(inode);
 927
 928         trace_ext4_drop_inode(inode, drop);
 929         return drop;
 930 }
 931
 932 static void ext4_i_callback(struct rcu_head *head)
 933 {
 934         struct inode *inode = container_of(head, struct inode, i_rcu);
 935         INIT_LIST_HEAD(&inode->i_dentry);
 936         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 937 }
 938
 939 static void ext4_destroy_inode(struct inode *inode)
 940 {
 941         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 942                 ext4_msg(inode->i_sb, KERN_ERR,
 943                          "Inode %lu (%p): orphan list check failed!",
 944                          inode->i_ino, EXT4_I(inode));
 945                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 946                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 947                                 true);
 948                 dump_stack();
 949         }
 950         call_rcu(&inode->i_rcu, ext4_i_callback);
 951 }
 952
 953 static void init_once(void *foo)
 954 {
 955         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 956
 957         INIT_LIST_HEAD(&ei->i_orphan);
 958 #ifdef CONFIG_EXT4_FS_XATTR
 959         init_rwsem(&ei->xattr_sem);
 960 #endif
 961         init_rwsem(&ei->i_data_sem);
 962         inode_init_once(&ei->vfs_inode);
 963 }
 964
 965 static int init_inodecache(void)
 966 {
 967         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 968                                              sizeof(struct ext4_inode_info),
 969                                              0, (SLAB_RECLAIM_ACCOUNT|
 970                                                 SLAB_MEM_SPREAD),
 971                                              init_once);
 972         if (ext4_inode_cachep == NULL)
 973                 return -ENOMEM;
 974         return 0;
 975 }
 976
 977 static void destroy_inodecache(void)
 978 {
 979         kmem_cache_destroy(ext4_inode_cachep);
 980 }
 981
 982 void ext4_clear_inode(struct inode *inode)
 983 {
 984         invalidate_inode_buffers(inode);
 985         end_writeback(inode);
 986         dquot_drop(inode);
 987         ext4_discard_preallocations(inode);
 988         if (EXT4_I(inode)->jinode) {
 989                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
 990                                                EXT4_I(inode)->jinode);
 991                 jbd2_free_inode(EXT4_I(inode)->jinode);
 992                 EXT4_I(inode)->jinode = NULL;
 993         }
 994 }
 995
 996 static inline void ext4_show_quota_options(struct seq_file *seq,
 997                                            struct super_block *sb)
 998 {
 999 #if defined(CONFIG_QUOTA)
1000         struct ext4_sb_info *sbi = EXT4_SB(sb);
1001
1002         if (sbi->s_jquota_fmt) {
1003                 char *fmtname = "";
1004
1005                 switch (sbi->s_jquota_fmt) {
1006                 case QFMT_VFS_OLD:
1007                         fmtname = "vfsold";
1008                         break;
1009                 case QFMT_VFS_V0:
1010                         fmtname = "vfsv0";
1011                         break;
1012                 case QFMT_VFS_V1:
1013                         fmtname = "vfsv1";
1014                         break;
1015                 }
1016                 seq_printf(seq, ",jqfmt=%s", fmtname);
1017         }
1018
1019         if (sbi->s_qf_names[USRQUOTA])
1020                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1021
1022         if (sbi->s_qf_names[GRPQUOTA])
1023                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1024
1025         if (test_opt(sb, USRQUOTA))
1026                 seq_puts(seq, ",usrquota");
1027
1028         if (test_opt(sb, GRPQUOTA))
1029                 seq_puts(seq, ",grpquota");
1030 #endif
1031 }
1032
1033 /*
1034  * Show an option if
1035  *  - it's set to a non-default value OR
1036  *  - if the per-sb default is different from the global default
1037  */
1038 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
1039 {
1040         int def_errors;
1041         unsigned long def_mount_opts;
1042         struct super_block *sb = vfs->mnt_sb;
1043         struct ext4_sb_info *sbi = EXT4_SB(sb);
1044         struct ext4_super_block *es = sbi->s_es;
1045
1046         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
1047         def_errors     = le16_to_cpu(es->s_errors);
1048
1049         if (sbi->s_sb_block != 1)
1050                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
1051         if (test_opt(sb, MINIX_DF))
1052                 seq_puts(seq, ",minixdf");
1053         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
1054                 seq_puts(seq, ",grpid");
1055         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
1056                 seq_puts(seq, ",nogrpid");
1057         if (sbi->s_resuid != EXT4_DEF_RESUID ||
1058             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
1059                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
1060         }
1061         if (sbi->s_resgid != EXT4_DEF_RESGID ||
1062             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
1063                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
1064         }
1065         if (test_opt(sb, ERRORS_RO)) {
1066                 if (def_errors == EXT4_ERRORS_PANIC ||
1067                     def_errors == EXT4_ERRORS_CONTINUE) {
1068                         seq_puts(seq, ",errors=remount-ro");
1069                 }
1070         }
1071         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1072                 seq_puts(seq, ",errors=continue");
1073         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1074                 seq_puts(seq, ",errors=panic");
1075         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
1076                 seq_puts(seq, ",nouid32");
1077         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
1078                 seq_puts(seq, ",debug");
1079 #ifdef CONFIG_EXT4_FS_XATTR
1080         if (test_opt(sb, XATTR_USER))
1081                 seq_puts(seq, ",user_xattr");
1082         if (!test_opt(sb, XATTR_USER))
1083                 seq_puts(seq, ",nouser_xattr");
1084 #endif
1085 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1086         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
1087                 seq_puts(seq, ",acl");
1088         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
1089                 seq_puts(seq, ",noacl");
1090 #endif
1091         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
1092                 seq_printf(seq, ",commit=%u",
1093                            (unsigned) (sbi->s_commit_interval / HZ));
1094         }
1095         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
1096                 seq_printf(seq, ",min_batch_time=%u",
1097                            (unsigned) sbi->s_min_batch_time);
1098         }
1099         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
1100                 seq_printf(seq, ",max_batch_time=%u",
1101                            (unsigned) sbi->s_max_batch_time);
1102         }
1103
1104         /*
1105          * We're changing the default of barrier mount option, so
1106          * let's always display its mount state so it's clear what its
1107          * status is.
1108          */
1109         seq_puts(seq, ",barrier=");
1110         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
1111         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
1112                 seq_puts(seq, ",journal_async_commit");
1113         else if (test_opt(sb, JOURNAL_CHECKSUM))
1114                 seq_puts(seq, ",journal_checksum");
1115         if (test_opt(sb, I_VERSION))
1116                 seq_puts(seq, ",i_version");
1117         if (!test_opt(sb, DELALLOC) &&
1118             !(def_mount_opts & EXT4_DEFM_NODELALLOC))
1119                 seq_puts(seq, ",nodelalloc");
1120
1121         if (!test_opt(sb, MBLK_IO_SUBMIT))
1122                 seq_puts(seq, ",nomblk_io_submit");
1123         if (sbi->s_stripe)
1124                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
1125         /*
1126          * journal mode get enabled in different ways
1127          * So just print the value even if we didn't specify it
1128          */
1129         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1130                 seq_puts(seq, ",data=journal");
1131         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1132                 seq_puts(seq, ",data=ordered");
1133         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1134                 seq_puts(seq, ",data=writeback");
1135
1136         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1137                 seq_printf(seq, ",inode_readahead_blks=%u",
1138                            sbi->s_inode_readahead_blks);
1139
1140         if (test_opt(sb, DATA_ERR_ABORT))
1141                 seq_puts(seq, ",data_err=abort");
1142
1143         if (test_opt(sb, NO_AUTO_DA_ALLOC))
1144                 seq_puts(seq, ",noauto_da_alloc");
1145
1146         if (test_opt(sb, DISCARD) && !(def_mount_opts & EXT4_DEFM_DISCARD))
1147                 seq_puts(seq, ",discard");
1148
1149         if (test_opt(sb, NOLOAD))
1150                 seq_puts(seq, ",norecovery");
1151
1152         if (test_opt(sb, DIOREAD_NOLOCK))
1153                 seq_puts(seq, ",dioread_nolock");
1154
1155         if (test_opt(sb, BLOCK_VALIDITY) &&
1156             !(def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY))
1157                 seq_puts(seq, ",block_validity");
1158
1159         if (!test_opt(sb, INIT_INODE_TABLE))
1160                 seq_puts(seq, ",noinit_itable");
1161         else if (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)
1162                 seq_printf(seq, ",init_itable=%u",
1163                            (unsigned) sbi->s_li_wait_mult);
1164
1165         ext4_show_quota_options(seq, sb);
1166
1167         return 0;
1168 }
1169
1170 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1171                                         u64 ino, u32 generation)
1172 {
1173         struct inode *inode;
1174
1175         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1176                 return ERR_PTR(-ESTALE);
1177         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1178                 return ERR_PTR(-ESTALE);
1179
1180         /* iget isn't really right if the inode is currently unallocated!!
1181          *
1182          * ext4_read_inode will return a bad_inode if the inode had been
1183          * deleted, so we should be safe.
1184          *
1185          * Currently we don't know the generation for parent directory, so
1186          * a generation of 0 means "accept any"
1187          */
1188         inode = ext4_iget(sb, ino);
1189         if (IS_ERR(inode))
1190                 return ERR_CAST(inode);
1191         if (generation && inode->i_generation != generation) {
1192                 iput(inode);
1193                 return ERR_PTR(-ESTALE);
1194         }
1195
1196         return inode;
1197 }
1198
1199 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1200                                         int fh_len, int fh_type)
1201 {
1202         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1203                                     ext4_nfs_get_inode);
1204 }
1205
1206 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1207                                         int fh_len, int fh_type)
1208 {
1209         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1210                                     ext4_nfs_get_inode);
1211 }
1212
1213 /*
1214  * Try to release metadata pages (indirect blocks, directories) which are
1215  * mapped via the block device.  Since these pages could have journal heads
1216  * which would prevent try_to_free_buffers() from freeing them, we must use
1217  * jbd2 layer's try_to_free_buffers() function to release them.
1218  */
1219 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1220                                  gfp_t wait)
1221 {
1222         journal_t *journal = EXT4_SB(sb)->s_journal;
1223
1224         WARN_ON(PageChecked(page));
1225         if (!page_has_buffers(page))
1226                 return 0;
1227         if (journal)
1228                 return jbd2_journal_try_to_free_buffers(journal, page,
1229                                                         wait & ~__GFP_WAIT);
1230         return try_to_free_buffers(page);
1231 }
1232
1233 #ifdef CONFIG_QUOTA
1234 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1235 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1236
1237 static int ext4_write_dquot(struct dquot *dquot);
1238 static int ext4_acquire_dquot(struct dquot *dquot);
1239 static int ext4_release_dquot(struct dquot *dquot);
1240 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1241 static int ext4_write_info(struct super_block *sb, int type);
1242 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1243                          struct path *path);
1244 static int ext4_quota_off(struct super_block *sb, int type);
1245 static int ext4_quota_on_mount(struct super_block *sb, int type);
1246 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1247                                size_t len, loff_t off);
1248 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1249                                 const char *data, size_t len, loff_t off);
1250
1251 static const struct dquot_operations ext4_quota_operations = {
1252         .get_reserved_space = ext4_get_reserved_space,
1253         .write_dquot    = ext4_write_dquot,
1254         .acquire_dquot  = ext4_acquire_dquot,
1255         .release_dquot  = ext4_release_dquot,
1256         .mark_dirty     = ext4_mark_dquot_dirty,
1257         .write_info     = ext4_write_info,
1258         .alloc_dquot    = dquot_alloc,
1259         .destroy_dquot  = dquot_destroy,
1260 };
1261
1262 static const struct quotactl_ops ext4_qctl_operations = {
1263         .quota_on       = ext4_quota_on,
1264         .quota_off      = ext4_quota_off,
1265         .quota_sync     = dquot_quota_sync,
1266         .get_info       = dquot_get_dqinfo,
1267         .set_info       = dquot_set_dqinfo,
1268         .get_dqblk      = dquot_get_dqblk,
1269         .set_dqblk      = dquot_set_dqblk
1270 };
1271 #endif
1272
1273 static const struct super_operations ext4_sops = {
1274         .alloc_inode    = ext4_alloc_inode,
1275         .destroy_inode  = ext4_destroy_inode,
1276         .write_inode    = ext4_write_inode,
1277         .dirty_inode    = ext4_dirty_inode,
1278         .drop_inode     = ext4_drop_inode,
1279         .evict_inode    = ext4_evict_inode,
1280         .put_super      = ext4_put_super,
1281         .sync_fs        = ext4_sync_fs,
1282         .freeze_fs      = ext4_freeze,
1283         .unfreeze_fs    = ext4_unfreeze,
1284         .statfs         = ext4_statfs,
1285         .remount_fs     = ext4_remount,
1286         .show_options   = ext4_show_options,
1287 #ifdef CONFIG_QUOTA
1288         .quota_read     = ext4_quota_read,
1289         .quota_write    = ext4_quota_write,
1290 #endif
1291         .bdev_try_to_free_page = bdev_try_to_free_page,
1292 };
1293
1294 static const struct super_operations ext4_nojournal_sops = {
1295         .alloc_inode    = ext4_alloc_inode,
1296         .destroy_inode  = ext4_destroy_inode,
1297         .write_inode    = ext4_write_inode,
1298         .dirty_inode    = ext4_dirty_inode,
1299         .drop_inode     = ext4_drop_inode,
1300         .evict_inode    = ext4_evict_inode,
1301         .write_super    = ext4_write_super,
1302         .put_super      = ext4_put_super,
1303         .statfs         = ext4_statfs,
1304         .remount_fs     = ext4_remount,
1305         .show_options   = ext4_show_options,
1306 #ifdef CONFIG_QUOTA
1307         .quota_read     = ext4_quota_read,
1308         .quota_write    = ext4_quota_write,
1309 #endif
1310         .bdev_try_to_free_page = bdev_try_to_free_page,
1311 };
1312
1313 static const struct export_operations ext4_export_ops = {
1314         .fh_to_dentry = ext4_fh_to_dentry,
1315         .fh_to_parent = ext4_fh_to_parent,
1316         .get_parent = ext4_get_parent,
1317 };
1318
1319 enum {
1320         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1321         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1322         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1323         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1324         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1325         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1326         Opt_journal_update, Opt_journal_dev,
1327         Opt_journal_checksum, Opt_journal_async_commit,
1328         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1329         Opt_data_err_abort, Opt_data_err_ignore,
1330         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1331         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1332         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1333         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1334         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1335         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1336         Opt_inode_readahead_blks, Opt_journal_ioprio,
1337         Opt_dioread_nolock, Opt_dioread_lock,
1338         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1339 };
1340
1341 static const match_table_t tokens = {
1342         {Opt_bsd_df, "bsddf"},
1343         {Opt_minix_df, "minixdf"},
1344         {Opt_grpid, "grpid"},
1345         {Opt_grpid, "bsdgroups"},
1346         {Opt_nogrpid, "nogrpid"},
1347         {Opt_nogrpid, "sysvgroups"},
1348         {Opt_resgid, "resgid=%u"},
1349         {Opt_resuid, "resuid=%u"},
1350         {Opt_sb, "sb=%u"},
1351         {Opt_err_cont, "errors=continue"},
1352         {Opt_err_panic, "errors=panic"},
1353         {Opt_err_ro, "errors=remount-ro"},
1354         {Opt_nouid32, "nouid32"},
1355         {Opt_debug, "debug"},
1356         {Opt_oldalloc, "oldalloc"},
1357         {Opt_orlov, "orlov"},
1358         {Opt_user_xattr, "user_xattr"},
1359         {Opt_nouser_xattr, "nouser_xattr"},
1360         {Opt_acl, "acl"},
1361         {Opt_noacl, "noacl"},
1362         {Opt_noload, "noload"},
1363         {Opt_noload, "norecovery"},
1364         {Opt_nobh, "nobh"},
1365         {Opt_bh, "bh"},
1366         {Opt_commit, "commit=%u"},
1367         {Opt_min_batch_time, "min_batch_time=%u"},
1368         {Opt_max_batch_time, "max_batch_time=%u"},
1369         {Opt_journal_update, "journal=update"},
1370         {Opt_journal_dev, "journal_dev=%u"},
1371         {Opt_journal_checksum, "journal_checksum"},
1372         {Opt_journal_async_commit, "journal_async_commit"},
1373         {Opt_abort, "abort"},
1374         {Opt_data_journal, "data=journal"},
1375         {Opt_data_ordered, "data=ordered"},
1376         {Opt_data_writeback, "data=writeback"},
1377         {Opt_data_err_abort, "data_err=abort"},
1378         {Opt_data_err_ignore, "data_err=ignore"},
1379         {Opt_offusrjquota, "usrjquota="},
1380         {Opt_usrjquota, "usrjquota=%s"},
1381         {Opt_offgrpjquota, "grpjquota="},
1382         {Opt_grpjquota, "grpjquota=%s"},
1383         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1384         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1385         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1386         {Opt_grpquota, "grpquota"},
1387         {Opt_noquota, "noquota"},
1388         {Opt_quota, "quota"},
1389         {Opt_usrquota, "usrquota"},
1390         {Opt_barrier, "barrier=%u"},
1391         {Opt_barrier, "barrier"},
1392         {Opt_nobarrier, "nobarrier"},
1393         {Opt_i_version, "i_version"},
1394         {Opt_stripe, "stripe=%u"},
1395         {Opt_resize, "resize"},
1396         {Opt_delalloc, "delalloc"},
1397         {Opt_nodelalloc, "nodelalloc"},
1398         {Opt_mblk_io_submit, "mblk_io_submit"},
1399         {Opt_nomblk_io_submit, "nomblk_io_submit"},
1400         {Opt_block_validity, "block_validity"},
1401         {Opt_noblock_validity, "noblock_validity"},
1402         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1403         {Opt_journal_ioprio, "journal_ioprio=%u"},
1404         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1405         {Opt_auto_da_alloc, "auto_da_alloc"},
1406         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1407         {Opt_dioread_nolock, "dioread_nolock"},
1408         {Opt_dioread_lock, "dioread_lock"},
1409         {Opt_discard, "discard"},
1410         {Opt_nodiscard, "nodiscard"},
1411         {Opt_init_itable, "init_itable=%u"},
1412         {Opt_init_itable, "init_itable"},
1413         {Opt_noinit_itable, "noinit_itable"},
1414         {Opt_err, NULL},
1415 };
1416
1417 static ext4_fsblk_t get_sb_block(void **data)
1418 {
1419         ext4_fsblk_t    sb_block;
1420         char            *options = (char *) *data;
1421
1422         if (!options || strncmp(options, "sb=", 3) != 0)
1423                 return 1;       /* Default location */
1424
1425         options += 3;
1426         /* TODO: use simple_strtoll with >32bit ext4 */
1427         sb_block = simple_strtoul(options, &options, 0);
1428         if (*options && *options != ',') {
1429                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1430                        (char *) *data);
1431                 return 1;
1432         }
1433         if (*options == ',')
1434                 options++;
1435         *data = (void *) options;
1436
1437         return sb_block;
1438 }
1439
1440 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1441 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1442         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1443
1444 #ifdef CONFIG_QUOTA
1445 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1446 {
1447         struct ext4_sb_info *sbi = EXT4_SB(sb);
1448         char *qname;
1449
1450         if (sb_any_quota_loaded(sb) &&
1451                 !sbi->s_qf_names[qtype]) {
1452                 ext4_msg(sb, KERN_ERR,
1453                         "Cannot change journaled "
1454                         "quota options when quota turned on");
1455                 return 0;
1456         }
1457         qname = match_strdup(args);
1458         if (!qname) {
1459                 ext4_msg(sb, KERN_ERR,
1460                         "Not enough memory for storing quotafile name");
1461                 return 0;
1462         }
1463         if (sbi->s_qf_names[qtype] &&
1464                 strcmp(sbi->s_qf_names[qtype], qname)) {
1465                 ext4_msg(sb, KERN_ERR,
1466                         "%s quota file already specified", QTYPE2NAME(qtype));
1467                 kfree(qname);
1468                 return 0;
1469         }
1470         sbi->s_qf_names[qtype] = qname;
1471         if (strchr(sbi->s_qf_names[qtype], '/')) {
1472                 ext4_msg(sb, KERN_ERR,
1473                         "quotafile must be on filesystem root");
1474                 kfree(sbi->s_qf_names[qtype]);
1475                 sbi->s_qf_names[qtype] = NULL;
1476                 return 0;
1477         }
1478         set_opt(sb, QUOTA);
1479         return 1;
1480 }
1481
1482 static int clear_qf_name(struct super_block *sb, int qtype)
1483 {
1484
1485         struct ext4_sb_info *sbi = EXT4_SB(sb);
1486
1487         if (sb_any_quota_loaded(sb) &&
1488                 sbi->s_qf_names[qtype]) {
1489                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1490                         " when quota turned on");
1491                 return 0;
1492         }
1493         /*
1494          * The space will be released later when all options are confirmed
1495          * to be correct
1496          */
1497         sbi->s_qf_names[qtype] = NULL;
1498         return 1;
1499 }
1500 #endif
1501
1502 static int parse_options(char *options, struct super_block *sb,
1503                          unsigned long *journal_devnum,
1504                          unsigned int *journal_ioprio,
1505                          ext4_fsblk_t *n_blocks_count, int is_remount)
1506 {
1507         struct ext4_sb_info *sbi = EXT4_SB(sb);
1508         char *p;
1509         substring_t args[MAX_OPT_ARGS];
1510         int data_opt = 0;
1511         int option;
1512 #ifdef CONFIG_QUOTA
1513         int qfmt;
1514 #endif
1515
1516         if (!options)
1517                 return 1;
1518
1519         while ((p = strsep(&options, ",")) != NULL) {
1520                 int token;
1521                 if (!*p)
1522                         continue;
1523
1524                 /*
1525                  * Initialize args struct so we know whether arg was
1526                  * found; some options take optional arguments.
1527                  */
1528                 args[0].to = args[0].from = NULL;
1529                 token = match_token(p, tokens, args);
1530                 switch (token) {
1531                 case Opt_bsd_df:
1532                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1533                         clear_opt(sb, MINIX_DF);
1534                         break;
1535                 case Opt_minix_df:
1536                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1537                         set_opt(sb, MINIX_DF);
1538
1539                         break;
1540                 case Opt_grpid:
1541                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1542                         set_opt(sb, GRPID);
1543
1544                         break;
1545                 case Opt_nogrpid:
1546                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1547                         clear_opt(sb, GRPID);
1548
1549                         break;
1550                 case Opt_resuid:
1551                         if (match_int(&args[0], &option))
1552                                 return 0;
1553                         sbi->s_resuid = option;
1554                         break;
1555                 case Opt_resgid:
1556                         if (match_int(&args[0], &option))
1557                                 return 0;
1558                         sbi->s_resgid = option;
1559                         break;
1560                 case Opt_sb:
1561                         /* handled by get_sb_block() instead of here */
1562                         /* *sb_block = match_int(&args[0]); */
1563                         break;
1564                 case Opt_err_panic:
1565                         clear_opt(sb, ERRORS_CONT);
1566                         clear_opt(sb, ERRORS_RO);
1567                         set_opt(sb, ERRORS_PANIC);
1568                         break;
1569                 case Opt_err_ro:
1570                         clear_opt(sb, ERRORS_CONT);
1571                         clear_opt(sb, ERRORS_PANIC);
1572                         set_opt(sb, ERRORS_RO);
1573                         break;
1574                 case Opt_err_cont:
1575                         clear_opt(sb, ERRORS_RO);
1576                         clear_opt(sb, ERRORS_PANIC);
1577                         set_opt(sb, ERRORS_CONT);
1578                         break;
1579                 case Opt_nouid32:
1580                         set_opt(sb, NO_UID32);
1581                         break;
1582                 case Opt_debug:
1583                         set_opt(sb, DEBUG);
1584                         break;
1585                 case Opt_oldalloc:
1586                         ext4_msg(sb, KERN_WARNING,
1587                                  "Ignoring deprecated oldalloc option");
1588                         break;
1589                 case Opt_orlov:
1590                         ext4_msg(sb, KERN_WARNING,
1591                                  "Ignoring deprecated orlov option");
1592                         break;
1593 #ifdef CONFIG_EXT4_FS_XATTR
1594                 case Opt_user_xattr:
1595                         set_opt(sb, XATTR_USER);
1596                         break;
1597                 case Opt_nouser_xattr:
1598                         clear_opt(sb, XATTR_USER);
1599                         break;
1600 #else
1601                 case Opt_user_xattr:
1602                 case Opt_nouser_xattr:
1603                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1604                         break;
1605 #endif
1606 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1607                 case Opt_acl:
1608                         set_opt(sb, POSIX_ACL);
1609                         break;
1610                 case Opt_noacl:
1611                         clear_opt(sb, POSIX_ACL);
1612                         break;
1613 #else
1614                 case Opt_acl:
1615                 case Opt_noacl:
1616                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1617                         break;
1618 #endif
1619                 case Opt_journal_update:
1620                         /* @@@ FIXME */
1621                         /* Eventually we will want to be able to create
1622                            a journal file here.  For now, only allow the
1623                            user to specify an existing inode to be the
1624                            journal file. */
1625                         if (is_remount) {
1626                                 ext4_msg(sb, KERN_ERR,
1627                                          "Cannot specify journal on remount");
1628                                 return 0;
1629                         }
1630                         set_opt(sb, UPDATE_JOURNAL);
1631                         break;
1632                 case Opt_journal_dev:
1633                         if (is_remount) {
1634                                 ext4_msg(sb, KERN_ERR,
1635                                         "Cannot specify journal on remount");
1636                                 return 0;
1637                         }
1638                         if (match_int(&args[0], &option))
1639                                 return 0;
1640                         *journal_devnum = option;
1641                         break;
1642                 case Opt_journal_checksum:
1643                         set_opt(sb, JOURNAL_CHECKSUM);
1644                         break;
1645                 case Opt_journal_async_commit:
1646                         set_opt(sb, JOURNAL_ASYNC_COMMIT);
1647                         set_opt(sb, JOURNAL_CHECKSUM);
1648                         break;
1649                 case Opt_noload:
1650                         set_opt(sb, NOLOAD);
1651                         break;
1652                 case Opt_commit:
1653                         if (match_int(&args[0], &option))
1654                                 return 0;
1655                         if (option < 0)
1656                                 return 0;
1657                         if (option == 0)
1658                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1659                         sbi->s_commit_interval = HZ * option;
1660                         break;
1661                 case Opt_max_batch_time:
1662                         if (match_int(&args[0], &option))
1663                                 return 0;
1664                         if (option < 0)
1665                                 return 0;
1666                         sbi->s_max_batch_time = option;
1667                         break;
1668                 case Opt_min_batch_time:
1669                         if (match_int(&args[0], &option))
1670                                 return 0;
1671                         if (option < 0)
1672                                 return 0;
1673                         sbi->s_min_batch_time = option;
1674                         break;
1675                 case Opt_data_journal:
1676                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1677                         goto datacheck;
1678                 case Opt_data_ordered:
1679                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1680                         goto datacheck;
1681                 case Opt_data_writeback:
1682                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1683                 datacheck:
1684                         if (is_remount) {
1685                                 if (!sbi->s_journal)
1686                                         ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1687                                 else if (test_opt(sb, DATA_FLAGS) != data_opt) {
1688                                         ext4_msg(sb, KERN_ERR,
1689                                                 "Cannot change data mode on remount");
1690                                         return 0;
1691                                 }
1692                         } else {
1693                                 clear_opt(sb, DATA_FLAGS);
1694                                 sbi->s_mount_opt |= data_opt;
1695                         }
1696                         break;
1697                 case Opt_data_err_abort:
1698                         set_opt(sb, DATA_ERR_ABORT);
1699                         break;
1700                 case Opt_data_err_ignore:
1701                         clear_opt(sb, DATA_ERR_ABORT);
1702                         break;
1703 #ifdef CONFIG_QUOTA
1704                 case Opt_usrjquota:
1705                         if (!set_qf_name(sb, USRQUOTA, &args[0]))
1706                                 return 0;
1707                         break;
1708                 case Opt_grpjquota:
1709                         if (!set_qf_name(sb, GRPQUOTA, &args[0]))
1710                                 return 0;
1711                         break;
1712                 case Opt_offusrjquota:
1713                         if (!clear_qf_name(sb, USRQUOTA))
1714                                 return 0;
1715                         break;
1716                 case Opt_offgrpjquota:
1717                         if (!clear_qf_name(sb, GRPQUOTA))
1718                                 return 0;
1719                         break;
1720
1721                 case Opt_jqfmt_vfsold:
1722                         qfmt = QFMT_VFS_OLD;
1723                         goto set_qf_format;
1724                 case Opt_jqfmt_vfsv0:
1725                         qfmt = QFMT_VFS_V0;
1726                         goto set_qf_format;
1727                 case Opt_jqfmt_vfsv1:
1728                         qfmt = QFMT_VFS_V1;
1729 set_qf_format:
1730                         if (sb_any_quota_loaded(sb) &&
1731                             sbi->s_jquota_fmt != qfmt) {
1732                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1733                                         "journaled quota options when "
1734                                         "quota turned on");
1735                                 return 0;
1736                         }
1737                         sbi->s_jquota_fmt = qfmt;
1738                         break;
1739                 case Opt_quota:
1740                 case Opt_usrquota:
1741                         set_opt(sb, QUOTA);
1742                         set_opt(sb, USRQUOTA);
1743                         break;
1744                 case Opt_grpquota:
1745                         set_opt(sb, QUOTA);
1746                         set_opt(sb, GRPQUOTA);
1747                         break;
1748                 case Opt_noquota:
1749                         if (sb_any_quota_loaded(sb)) {
1750                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1751                                         "options when quota turned on");
1752                                 return 0;
1753                         }
1754                         clear_opt(sb, QUOTA);
1755                         clear_opt(sb, USRQUOTA);
1756                         clear_opt(sb, GRPQUOTA);
1757                         break;
1758 #else
1759                 case Opt_quota:
1760                 case Opt_usrquota:
1761                 case Opt_grpquota:
1762                         ext4_msg(sb, KERN_ERR,
1763                                 "quota options not supported");
1764                         break;
1765                 case Opt_usrjquota:
1766                 case Opt_grpjquota:
1767                 case Opt_offusrjquota:
1768                 case Opt_offgrpjquota:
1769                 case Opt_jqfmt_vfsold:
1770                 case Opt_jqfmt_vfsv0:
1771                 case Opt_jqfmt_vfsv1:
1772                         ext4_msg(sb, KERN_ERR,
1773                                 "journaled quota options not supported");
1774                         break;
1775                 case Opt_noquota:
1776                         break;
1777 #endif
1778                 case Opt_abort:
1779                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1780                         break;
1781                 case Opt_nobarrier:
1782                         clear_opt(sb, BARRIER);
1783                         break;
1784                 case Opt_barrier:
1785                         if (args[0].from) {
1786                                 if (match_int(&args[0], &option))
1787                                         return 0;
1788                         } else
1789                                 option = 1;     /* No argument, default to 1 */
1790                         if (option)
1791                                 set_opt(sb, BARRIER);
1792                         else
1793                                 clear_opt(sb, BARRIER);
1794                         break;
1795                 case Opt_ignore:
1796                         break;
1797                 case Opt_resize:
1798                         if (!is_remount) {
1799                                 ext4_msg(sb, KERN_ERR,
1800                                         "resize option only available "
1801                                         "for remount");
1802                                 return 0;
1803                         }
1804                         if (match_int(&args[0], &option) != 0)
1805                                 return 0;
1806                         *n_blocks_count = option;
1807                         break;
1808                 case Opt_nobh:
1809                         ext4_msg(sb, KERN_WARNING,
1810                                  "Ignoring deprecated nobh option");
1811                         break;
1812                 case Opt_bh:
1813                         ext4_msg(sb, KERN_WARNING,
1814                                  "Ignoring deprecated bh option");
1815                         break;
1816                 case Opt_i_version:
1817                         set_opt(sb, I_VERSION);
1818                         sb->s_flags |= MS_I_VERSION;
1819                         break;
1820                 case Opt_nodelalloc:
1821                         clear_opt(sb, DELALLOC);
1822                         clear_opt2(sb, EXPLICIT_DELALLOC);
1823                         break;
1824                 case Opt_mblk_io_submit:
1825                         set_opt(sb, MBLK_IO_SUBMIT);
1826                         break;
1827                 case Opt_nomblk_io_submit:
1828                         clear_opt(sb, MBLK_IO_SUBMIT);
1829                         break;
1830                 case Opt_stripe:
1831                         if (match_int(&args[0], &option))
1832                                 return 0;
1833                         if (option < 0)
1834                                 return 0;
1835                         sbi->s_stripe = option;
1836                         break;
1837                 case Opt_delalloc:
1838                         set_opt(sb, DELALLOC);
1839                         set_opt2(sb, EXPLICIT_DELALLOC);
1840                         break;
1841                 case Opt_block_validity:
1842                         set_opt(sb, BLOCK_VALIDITY);
1843                         break;
1844                 case Opt_noblock_validity:
1845                         clear_opt(sb, BLOCK_VALIDITY);
1846                         break;
1847                 case Opt_inode_readahead_blks:
1848                         if (match_int(&args[0], &option))
1849                                 return 0;
1850                         if (option < 0 || option > (1 << 30))
1851                                 return 0;
1852                         if (option && !is_power_of_2(option)) {
1853                                 ext4_msg(sb, KERN_ERR,
1854                                          "EXT4-fs: inode_readahead_blks"
1855                                          " must be a power of 2");
1856                                 return 0;
1857                         }
1858                         sbi->s_inode_readahead_blks = option;
1859                         break;
1860                 case Opt_journal_ioprio:
1861                         if (match_int(&args[0], &option))
1862                                 return 0;
1863                         if (option < 0 || option > 7)
1864                                 break;
1865                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1866                                                             option);
1867                         break;
1868                 case Opt_noauto_da_alloc:
1869                         set_opt(sb, NO_AUTO_DA_ALLOC);
1870                         break;
1871                 case Opt_auto_da_alloc:
1872                         if (args[0].from) {
1873                                 if (match_int(&args[0], &option))
1874                                         return 0;
1875                         } else
1876                                 option = 1;     /* No argument, default to 1 */
1877                         if (option)
1878                                 clear_opt(sb, NO_AUTO_DA_ALLOC);
1879                         else
1880                                 set_opt(sb,NO_AUTO_DA_ALLOC);
1881                         break;
1882                 case Opt_discard:
1883                         set_opt(sb, DISCARD);
1884                         break;
1885                 case Opt_nodiscard:
1886                         clear_opt(sb, DISCARD);
1887                         break;
1888                 case Opt_dioread_nolock:
1889                         set_opt(sb, DIOREAD_NOLOCK);
1890                         break;
1891                 case Opt_dioread_lock:
1892                         clear_opt(sb, DIOREAD_NOLOCK);
1893                         break;
1894                 case Opt_init_itable:
1895                         set_opt(sb, INIT_INODE_TABLE);
1896                         if (args[0].from) {
1897                                 if (match_int(&args[0], &option))
1898                                         return 0;
1899                         } else
1900                                 option = EXT4_DEF_LI_WAIT_MULT;
1901                         if (option < 0)
1902                                 return 0;
1903                         sbi->s_li_wait_mult = option;
1904                         break;
1905                 case Opt_noinit_itable:
1906                         clear_opt(sb, INIT_INODE_TABLE);
1907                         break;
1908                 default:
1909                         ext4_msg(sb, KERN_ERR,
1910                                "Unrecognized mount option \"%s\" "
1911                                "or missing value", p);
1912                         return 0;
1913                 }
1914         }
1915 #ifdef CONFIG_QUOTA
1916         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1917                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1918                         clear_opt(sb, USRQUOTA);
1919
1920                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1921                         clear_opt(sb, GRPQUOTA);
1922
1923                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1924                         ext4_msg(sb, KERN_ERR, "old and new quota "
1925                                         "format mixing");
1926                         return 0;
1927                 }
1928
1929                 if (!sbi->s_jquota_fmt) {
1930                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1931                                         "not specified");
1932                         return 0;
1933                 }
1934         } else {
1935                 if (sbi->s_jquota_fmt) {
1936                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1937                                         "specified with no journaling "
1938                                         "enabled");
1939                         return 0;
1940                 }
1941         }
1942 #endif
1943         if (test_opt(sb, DIOREAD_NOLOCK)) {
1944                 int blocksize =
1945                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1946
1947                 if (blocksize < PAGE_CACHE_SIZE) {
1948                         ext4_msg(sb, KERN_ERR, "can't mount with "
1949                                  "dioread_nolock if block size != PAGE_SIZE");
1950                         return 0;
1951                 }
1952         }
1953         return 1;
1954 }
1955
1956 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1957                             int read_only)
1958 {
1959         struct ext4_sb_info *sbi = EXT4_SB(sb);
1960         int res = 0;
1961
1962         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1963                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1964                          "forcing read-only mode");
1965                 res = MS_RDONLY;
1966         }
1967         if (read_only)
1968                 goto done;
1969         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1970                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1971                          "running e2fsck is recommended");
1972         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1973                 ext4_msg(sb, KERN_WARNING,
1974                          "warning: mounting fs with errors, "
1975                          "running e2fsck is recommended");
1976         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1977                  le16_to_cpu(es->s_mnt_count) >=
1978                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1979                 ext4_msg(sb, KERN_WARNING,
1980                          "warning: maximal mount count reached, "
1981                          "running e2fsck is recommended");
1982         else if (le32_to_cpu(es->s_checkinterval) &&
1983                 (le32_to_cpu(es->s_lastcheck) +
1984                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1985                 ext4_msg(sb, KERN_WARNING,
1986                          "warning: checktime reached, "
1987                          "running e2fsck is recommended");
1988         if (!sbi->s_journal)
1989                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1990         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1991                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1992         le16_add_cpu(&es->s_mnt_count, 1);
1993         es->s_mtime = cpu_to_le32(get_seconds());
1994         ext4_update_dynamic_rev(sb);
1995         if (sbi->s_journal)
1996                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1997
1998         ext4_commit_super(sb, 1);
1999 done:
2000         if (test_opt(sb, DEBUG))
2001                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2002                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2003                         sb->s_blocksize,
2004                         sbi->s_groups_count,
2005                         EXT4_BLOCKS_PER_GROUP(sb),
2006                         EXT4_INODES_PER_GROUP(sb),
2007                         sbi->s_mount_opt, sbi->s_mount_opt2);
2008
2009         cleancache_init_fs(sb);
2010         return res;
2011 }
2012
2013 static int ext4_fill_flex_info(struct super_block *sb)
2014 {
2015         struct ext4_sb_info *sbi = EXT4_SB(sb);
2016         struct ext4_group_desc *gdp = NULL;
2017         ext4_group_t flex_group_count;
2018         ext4_group_t flex_group;
2019         unsigned int groups_per_flex = 0;
2020         size_t size;
2021         int i;
2022
2023         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2024         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2025                 sbi->s_log_groups_per_flex = 0;
2026                 return 1;
2027         }
2028         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
2029
2030         /* We allocate both existing and potentially added groups */
2031         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
2032                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
2033                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
2034         size = flex_group_count * sizeof(struct flex_groups);
2035         sbi->s_flex_groups = ext4_kvzalloc(size, GFP_KERNEL);
2036         if (sbi->s_flex_groups == NULL) {
2037                 ext4_msg(sb, KERN_ERR, "not enough memory for %u flex groups",
2038                          flex_group_count);
2039                 goto failed;
2040         }
2041
2042         for (i = 0; i < sbi->s_groups_count; i++) {
2043                 gdp = ext4_get_group_desc(sb, i, NULL);
2044
2045                 flex_group = ext4_flex_group(sbi, i);
2046                 atomic_add(ext4_free_inodes_count(sb, gdp),
2047                            &sbi->s_flex_groups[flex_group].free_inodes);
2048                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2049                              &sbi->s_flex_groups[flex_group].free_clusters);
2050                 atomic_add(ext4_used_dirs_count(sb, gdp),
2051                            &sbi->s_flex_groups[flex_group].used_dirs);
2052         }
2053
2054         return 1;
2055 failed:
2056         return 0;
2057 }
2058
2059 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
2060                             struct ext4_group_desc *gdp)
2061 {
2062         __u16 crc = 0;
2063
2064         if (sbi->s_es->s_feature_ro_compat &
2065             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
2066                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
2067                 __le32 le_group = cpu_to_le32(block_group);
2068
2069                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2070                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2071                 crc = crc16(crc, (__u8 *)gdp, offset);
2072                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
2073                 /* for checksum of struct ext4_group_desc do the rest...*/
2074                 if ((sbi->s_es->s_feature_incompat &
2075                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2076                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
2077                         crc = crc16(crc, (__u8 *)gdp + offset,
2078                                     le16_to_cpu(sbi->s_es->s_desc_size) -
2079                                         offset);
2080         }
2081
2082         return cpu_to_le16(crc);
2083 }
2084
2085 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
2086                                 struct ext4_group_desc *gdp)
2087 {
2088         if ((sbi->s_es->s_feature_ro_compat &
2089              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
2090             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
2091                 return 0;
2092
2093         return 1;
2094 }
2095
2096 /* Called at mount-time, super-block is locked */
2097 static int ext4_check_descriptors(struct super_block *sb,
2098                                   ext4_group_t *first_not_zeroed)
2099 {
2100         struct ext4_sb_info *sbi = EXT4_SB(sb);
2101         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2102         ext4_fsblk_t last_block;
2103         ext4_fsblk_t block_bitmap;
2104         ext4_fsblk_t inode_bitmap;
2105         ext4_fsblk_t inode_table;
2106         int flexbg_flag = 0;
2107         ext4_group_t i, grp = sbi->s_groups_count;
2108
2109         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2110                 flexbg_flag = 1;
2111
2112         ext4_debug("Checking group descriptors");
2113
2114         for (i = 0; i < sbi->s_groups_count; i++) {
2115                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2116
2117                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2118                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2119                 else
2120                         last_block = first_block +
2121                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2122
2123                 if ((grp == sbi->s_groups_count) &&
2124                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2125                         grp = i;
2126
2127                 block_bitmap = ext4_block_bitmap(sb, gdp);
2128                 if (block_bitmap < first_block || block_bitmap > last_block) {
2129                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2130                                "Block bitmap for group %u not in group "
2131                                "(block %llu)!", i, block_bitmap);
2132                         return 0;
2133                 }
2134                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2135                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2136                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2137                                "Inode bitmap for group %u not in group "
2138                                "(block %llu)!", i, inode_bitmap);
2139                         return 0;
2140                 }
2141                 inode_table = ext4_inode_table(sb, gdp);
2142                 if (inode_table < first_block ||
2143                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2144                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2145                                "Inode table for group %u not in group "
2146                                "(block %llu)!", i, inode_table);
2147                         return 0;
2148                 }
2149                 ext4_lock_group(sb, i);
2150                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
2151                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2152                                  "Checksum for group %u failed (%u!=%u)",
2153                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2154                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2155                         if (!(sb->s_flags & MS_RDONLY)) {
2156                                 ext4_unlock_group(sb, i);
2157                                 return 0;
2158                         }
2159                 }
2160                 ext4_unlock_group(sb, i);
2161                 if (!flexbg_flag)
2162                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2163         }
2164         if (NULL != first_not_zeroed)
2165                 *first_not_zeroed = grp;
2166
2167         ext4_free_blocks_count_set(sbi->s_es,
2168                                    EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2169         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2170         return 1;
2171 }
2172
2173 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2174  * the superblock) which were deleted from all directories, but held open by
2175  * a process at the time of a crash.  We walk the list and try to delete these
2176  * inodes at recovery time (only with a read-write filesystem).
2177  *
2178  * In order to keep the orphan inode chain consistent during traversal (in
2179  * case of crash during recovery), we link each inode into the superblock
2180  * orphan list_head and handle it the same way as an inode deletion during
2181  * normal operation (which journals the operations for us).
2182  *
2183  * We only do an iget() and an iput() on each inode, which is very safe if we
2184  * accidentally point at an in-use or already deleted inode.  The worst that
2185  * can happen in this case is that we get a "bit already cleared" message from
2186  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2187  * e2fsck was run on this filesystem, and it must have already done the orphan
2188  * inode cleanup for us, so we can safely abort without any further action.
2189  */
2190 static void ext4_orphan_cleanup(struct super_block *sb,
2191                                 struct ext4_super_block *es)
2192 {
2193         unsigned int s_flags = sb->s_flags;
2194         int nr_orphans = 0, nr_truncates = 0;
2195 #ifdef CONFIG_QUOTA
2196         int i;
2197 #endif
2198         if (!es->s_last_orphan) {
2199                 jbd_debug(4, "no orphan inodes to clean up\n");
2200                 return;
2201         }
2202
2203         if (bdev_read_only(sb->s_bdev)) {
2204                 ext4_msg(sb, KERN_ERR, "write access "
2205                         "unavailable, skipping orphan cleanup");
2206                 return;
2207         }
2208
2209         /* Check if feature set would not allow a r/w mount */
2210         if (!ext4_feature_set_ok(sb, 0)) {
2211                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2212                          "unknown ROCOMPAT features");
2213                 return;
2214         }
2215
2216         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2217                 if (es->s_last_orphan)
2218                         jbd_debug(1, "Errors on filesystem, "
2219                                   "clearing orphan list.\n");
2220                 es->s_last_orphan = 0;
2221                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2222                 return;
2223         }
2224
2225         if (s_flags & MS_RDONLY) {
2226                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2227                 sb->s_flags &= ~MS_RDONLY;
2228         }
2229 #ifdef CONFIG_QUOTA
2230         /* Needed for iput() to work correctly and not trash data */
2231         sb->s_flags |= MS_ACTIVE;
2232         /* Turn on quotas so that they are updated correctly */
2233         for (i = 0; i < MAXQUOTAS; i++) {
2234                 if (EXT4_SB(sb)->s_qf_names[i]) {
2235                         int ret = ext4_quota_on_mount(sb, i);
2236                         if (ret < 0)
2237                                 ext4_msg(sb, KERN_ERR,
2238                                         "Cannot turn on journaled "
2239                                         "quota: error %d", ret);
2240                 }
2241         }
2242 #endif
2243
2244         while (es->s_last_orphan) {
2245                 struct inode *inode;
2246
2247                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2248                 if (IS_ERR(inode)) {
2249                         es->s_last_orphan = 0;
2250                         break;
2251                 }
2252
2253                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2254                 dquot_initialize(inode);
2255                 if (inode->i_nlink) {
2256                         ext4_msg(sb, KERN_DEBUG,
2257                                 "%s: truncating inode %lu to %lld bytes",
2258                                 __func__, inode->i_ino, inode->i_size);
2259                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2260                                   inode->i_ino, inode->i_size);
2261                         mutex_lock(&inode->i_mutex);
2262                         ext4_truncate(inode);
2263                         mutex_unlock(&inode->i_mutex);
2264                         nr_truncates++;
2265                 } else {
2266                         ext4_msg(sb, KERN_DEBUG,
2267                                 "%s: deleting unreferenced inode %lu",
2268                                 __func__, inode->i_ino);
2269                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2270                                   inode->i_ino);
2271                         nr_orphans++;
2272                 }
2273                 iput(inode);  /* The delete magic happens here! */
2274         }
2275
2276 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2277
2278         if (nr_orphans)
2279                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2280                        PLURAL(nr_orphans));
2281         if (nr_truncates)
2282                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2283                        PLURAL(nr_truncates));
2284 #ifdef CONFIG_QUOTA
2285         /* Turn quotas off */
2286         for (i = 0; i < MAXQUOTAS; i++) {
2287                 if (sb_dqopt(sb)->files[i])
2288                         dquot_quota_off(sb, i);
2289         }
2290 #endif
2291         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2292 }
2293
2294 /*
2295  * Maximal extent format file size.
2296  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2297  * extent format containers, within a sector_t, and within i_blocks
2298  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2299  * so that won't be a limiting factor.
2300  *
2301  * However there is other limiting factor. We do store extents in the form
2302  * of starting block and length, hence the resulting length of the extent
2303  * covering maximum file size must fit into on-disk format containers as
2304  * well. Given that length is always by 1 unit bigger than max unit (because
2305  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2306  *
2307  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2308  */
2309 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2310 {
2311         loff_t res;
2312         loff_t upper_limit = MAX_LFS_FILESIZE;
2313
2314         /* small i_blocks in vfs inode? */
2315         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2316                 /*
2317                  * CONFIG_LBDAF is not enabled implies the inode
2318                  * i_block represent total blocks in 512 bytes
2319                  * 32 == size of vfs inode i_blocks * 8
2320                  */
2321                 upper_limit = (1LL << 32) - 1;
2322
2323                 /* total blocks in file system block size */
2324                 upper_limit >>= (blkbits - 9);
2325                 upper_limit <<= blkbits;
2326         }
2327
2328         /*
2329          * 32-bit extent-start container, ee_block. We lower the maxbytes
2330          * by one fs block, so ee_len can cover the extent of maximum file
2331          * size
2332          */
2333         res = (1LL << 32) - 1;
2334         res <<= blkbits;
2335
2336         /* Sanity check against vm- & vfs- imposed limits */
2337         if (res > upper_limit)
2338                 res = upper_limit;
2339
2340         return res;
2341 }
2342
2343 /*
2344  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2345  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2346  * We need to be 1 filesystem block less than the 2^48 sector limit.
2347  */
2348 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2349 {
2350         loff_t res = EXT4_NDIR_BLOCKS;
2351         int meta_blocks;
2352         loff_t upper_limit;
2353         /* This is calculated to be the largest file size for a dense, block
2354          * mapped file such that the file's total number of 512-byte sectors,
2355          * including data and all indirect blocks, does not exceed (2^48 - 1).
2356          *
2357          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2358          * number of 512-byte sectors of the file.
2359          */
2360
2361         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2362                 /*
2363                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2364                  * the inode i_block field represents total file blocks in
2365                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2366                  */
2367                 upper_limit = (1LL << 32) - 1;
2368
2369                 /* total blocks in file system block size */
2370                 upper_limit >>= (bits - 9);
2371
2372         } else {
2373                 /*
2374                  * We use 48 bit ext4_inode i_blocks
2375                  * With EXT4_HUGE_FILE_FL set the i_blocks
2376                  * represent total number of blocks in
2377                  * file system block size
2378                  */
2379                 upper_limit = (1LL << 48) - 1;
2380
2381         }
2382
2383         /* indirect blocks */
2384         meta_blocks = 1;
2385         /* double indirect blocks */
2386         meta_blocks += 1 + (1LL << (bits-2));
2387         /* tripple indirect blocks */
2388         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2389
2390         upper_limit -= meta_blocks;
2391         upper_limit <<= bits;
2392
2393         res += 1LL << (bits-2);
2394         res += 1LL << (2*(bits-2));
2395         res += 1LL << (3*(bits-2));
2396         res <<= bits;
2397         if (res > upper_limit)
2398                 res = upper_limit;
2399
2400         if (res > MAX_LFS_FILESIZE)
2401                 res = MAX_LFS_FILESIZE;
2402
2403         return res;
2404 }
2405
2406 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2407                                    ext4_fsblk_t logical_sb_block, int nr)
2408 {
2409         struct ext4_sb_info *sbi = EXT4_SB(sb);
2410         ext4_group_t bg, first_meta_bg;
2411         int has_super = 0;
2412
2413         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2414
2415         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2416             nr < first_meta_bg)
2417                 return logical_sb_block + nr + 1;
2418         bg = sbi->s_desc_per_block * nr;
2419         if (ext4_bg_has_super(sb, bg))
2420                 has_super = 1;
2421
2422         return (has_super + ext4_group_first_block_no(sb, bg));
2423 }
2424
2425 /**
2426  * ext4_get_stripe_size: Get the stripe size.
2427  * @sbi: In memory super block info
2428  *
2429  * If we have specified it via mount option, then
2430  * use the mount option value. If the value specified at mount time is
2431  * greater than the blocks per group use the super block value.
2432  * If the super block value is greater than blocks per group return 0.
2433  * Allocator needs it be less than blocks per group.
2434  *
2435  */
2436 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2437 {
2438         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2439         unsigned long stripe_width =
2440                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2441         int ret;
2442
2443         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2444                 ret = sbi->s_stripe;
2445         else if (stripe_width <= sbi->s_blocks_per_group)
2446                 ret = stripe_width;
2447         else if (stride <= sbi->s_blocks_per_group)
2448                 ret = stride;
2449         else
2450                 ret = 0;
2451
2452         /*
2453          * If the stripe width is 1, this makes no sense and
2454          * we set it to 0 to turn off stripe handling code.
2455          */
2456         if (ret <= 1)
2457                 ret = 0;
2458
2459         return ret;
2460 }
2461
2462 /* sysfs supprt */
2463
2464 struct ext4_attr {
2465         struct attribute attr;
2466         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2467         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2468                          const char *, size_t);
2469         int offset;
2470 };
2471
2472 static int parse_strtoul(const char *buf,
2473                 unsigned long max, unsigned long *value)
2474 {
2475         char *endp;
2476
2477         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2478         endp = skip_spaces(endp);
2479         if (*endp || *value > max)
2480                 return -EINVAL;
2481
2482         return 0;
2483 }
2484
2485 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2486                                               struct ext4_sb_info *sbi,
2487                                               char *buf)
2488 {
2489         return snprintf(buf, PAGE_SIZE, "%llu\n",
2490                 (s64) EXT4_C2B(sbi,
2491                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2492 }
2493
2494 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2495                                          struct ext4_sb_info *sbi, char *buf)
2496 {
2497         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2498
2499         if (!sb->s_bdev->bd_part)
2500                 return snprintf(buf, PAGE_SIZE, "0\n");
2501         return snprintf(buf, PAGE_SIZE, "%lu\n",
2502                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2503                          sbi->s_sectors_written_start) >> 1);
2504 }
2505
2506 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2507                                           struct ext4_sb_info *sbi, char *buf)
2508 {
2509         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2510
2511         if (!sb->s_bdev->bd_part)
2512                 return snprintf(buf, PAGE_SIZE, "0\n");
2513         return snprintf(buf, PAGE_SIZE, "%llu\n",
2514                         (unsigned long long)(sbi->s_kbytes_written +
2515                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2516                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2517 }
2518
2519 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2520                                           struct ext4_sb_info *sbi,
2521                                           const char *buf, size_t count)
2522 {
2523         unsigned long t;
2524
2525         if (parse_strtoul(buf, 0x40000000, &t))
2526                 return -EINVAL;
2527
2528         if (t && !is_power_of_2(t))
2529                 return -EINVAL;
2530
2531         sbi->s_inode_readahead_blks = t;
2532         return count;
2533 }
2534
2535 static ssize_t sbi_ui_show(struct ext4_attr *a,
2536                            struct ext4_sb_info *sbi, char *buf)
2537 {
2538         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2539
2540         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2541 }
2542
2543 static ssize_t sbi_ui_store(struct ext4_attr *a,
2544                             struct ext4_sb_info *sbi,
2545                             const char *buf, size_t count)
2546 {
2547         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2548         unsigned long t;
2549
2550         if (parse_strtoul(buf, 0xffffffff, &t))
2551                 return -EINVAL;
2552         *ui = t;
2553         return count;
2554 }
2555
2556 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2557 static struct ext4_attr ext4_attr_##_name = {                   \
2558         .attr = {.name = __stringify(_name), .mode = _mode },   \
2559         .show   = _show,                                        \
2560         .store  = _store,                                       \
2561         .offset = offsetof(struct ext4_sb_info, _elname),       \
2562 }
2563 #define EXT4_ATTR(name, mode, show, store) \
2564 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2565
2566 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2567 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2568 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2569 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2570         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2571 #define ATTR_LIST(name) &ext4_attr_##name.attr
2572
2573 EXT4_RO_ATTR(delayed_allocation_blocks);
2574 EXT4_RO_ATTR(session_write_kbytes);
2575 EXT4_RO_ATTR(lifetime_write_kbytes);
2576 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2577                  inode_readahead_blks_store, s_inode_readahead_blks);
2578 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2579 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2580 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2581 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2582 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2583 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2584 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2585 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2586
2587 static struct attribute *ext4_attrs[] = {
2588         ATTR_LIST(delayed_allocation_blocks),
2589         ATTR_LIST(session_write_kbytes),
2590         ATTR_LIST(lifetime_write_kbytes),
2591         ATTR_LIST(inode_readahead_blks),
2592         ATTR_LIST(inode_goal),
2593         ATTR_LIST(mb_stats),
2594         ATTR_LIST(mb_max_to_scan),
2595         ATTR_LIST(mb_min_to_scan),
2596         ATTR_LIST(mb_order2_req),
2597         ATTR_LIST(mb_stream_req),
2598         ATTR_LIST(mb_group_prealloc),
2599         ATTR_LIST(max_writeback_mb_bump),
2600         NULL,
2601 };
2602
2603 /* Features this copy of ext4 supports */
2604 EXT4_INFO_ATTR(lazy_itable_init);
2605 EXT4_INFO_ATTR(batched_discard);
2606
2607 static struct attribute *ext4_feat_attrs[] = {
2608         ATTR_LIST(lazy_itable_init),
2609         ATTR_LIST(batched_discard),
2610         NULL,
2611 };
2612
2613 static ssize_t ext4_attr_show(struct kobject *kobj,
2614                               struct attribute *attr, char *buf)
2615 {
2616         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2617                                                 s_kobj);
2618         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2619
2620         return a->show ? a->show(a, sbi, buf) : 0;
2621 }
2622
2623 static ssize_t ext4_attr_store(struct kobject *kobj,
2624                                struct attribute *attr,
2625                                const char *buf, size_t len)
2626 {
2627         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2628                                                 s_kobj);
2629         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2630
2631         return a->store ? a->store(a, sbi, buf, len) : 0;
2632 }
2633
2634 static void ext4_sb_release(struct kobject *kobj)
2635 {
2636         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2637                                                 s_kobj);
2638         complete(&sbi->s_kobj_unregister);
2639 }
2640
2641 static const struct sysfs_ops ext4_attr_ops = {
2642         .show   = ext4_attr_show,
2643         .store  = ext4_attr_store,
2644 };
2645
2646 static struct kobj_type ext4_ktype = {
2647         .default_attrs  = ext4_attrs,
2648         .sysfs_ops      = &ext4_attr_ops,
2649         .release        = ext4_sb_release,
2650 };
2651
2652 static void ext4_feat_release(struct kobject *kobj)
2653 {
2654         complete(&ext4_feat->f_kobj_unregister);
2655 }
2656
2657 static struct kobj_type ext4_feat_ktype = {
2658         .default_attrs  = ext4_feat_attrs,
2659         .sysfs_ops      = &ext4_attr_ops,
2660         .release        = ext4_feat_release,
2661 };
2662
2663 /*
2664  * Check whether this filesystem can be mounted based on
2665  * the features present and the RDONLY/RDWR mount requested.
2666  * Returns 1 if this filesystem can be mounted as requested,
2667  * 0 if it cannot be.
2668  */
2669 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2670 {
2671         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2672                 ext4_msg(sb, KERN_ERR,
2673                         "Couldn't mount because of "
2674                         "unsupported optional features (%x)",
2675                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2676                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2677                 return 0;
2678         }
2679
2680         if (readonly)
2681                 return 1;
2682
2683         /* Check that feature set is OK for a read-write mount */
2684         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2685                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2686                          "unsupported optional features (%x)",
2687                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2688                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2689                 return 0;
2690         }
2691         /*
2692          * Large file size enabled file system can only be mounted
2693          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2694          */
2695         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2696                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2697                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2698                                  "cannot be mounted RDWR without "
2699                                  "CONFIG_LBDAF");
2700                         return 0;
2701                 }
2702         }
2703         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2704             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2705                 ext4_msg(sb, KERN_ERR,
2706                          "Can't support bigalloc feature without "
2707                          "extents feature\n");
2708                 return 0;
2709         }
2710         return 1;
2711 }
2712
2713 /*
2714  * This function is called once a day if we have errors logged
2715  * on the file system
2716  */
2717 static void print_daily_error_info(unsigned long arg)
2718 {
2719         struct super_block *sb = (struct super_block *) arg;
2720         struct ext4_sb_info *sbi;
2721         struct ext4_super_block *es;
2722
2723         sbi = EXT4_SB(sb);
2724         es = sbi->s_es;
2725
2726         if (es->s_error_count)
2727                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2728                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2729                          le32_to_cpu(es->s_error_count));
2730         if (es->s_first_error_time) {
2731                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2732                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2733                        (int) sizeof(es->s_first_error_func),
2734                        es->s_first_error_func,
2735                        le32_to_cpu(es->s_first_error_line));
2736                 if (es->s_first_error_ino)
2737                         printk(": inode %u",
2738                                le32_to_cpu(es->s_first_error_ino));
2739                 if (es->s_first_error_block)
2740                         printk(": block %llu", (unsigned long long)
2741                                le64_to_cpu(es->s_first_error_block));
2742                 printk("\n");
2743         }
2744         if (es->s_last_error_time) {
2745                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2746                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2747                        (int) sizeof(es->s_last_error_func),
2748                        es->s_last_error_func,
2749                        le32_to_cpu(es->s_last_error_line));
2750                 if (es->s_last_error_ino)
2751                         printk(": inode %u",
2752                                le32_to_cpu(es->s_last_error_ino));
2753                 if (es->s_last_error_block)
2754                         printk(": block %llu", (unsigned long long)
2755                                le64_to_cpu(es->s_last_error_block));
2756                 printk("\n");
2757         }
2758         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2759 }
2760
2761 /* Find next suitable group and run ext4_init_inode_table */
2762 static int ext4_run_li_request(struct ext4_li_request *elr)
2763 {
2764         struct ext4_group_desc *gdp = NULL;
2765         ext4_group_t group, ngroups;
2766         struct super_block *sb;
2767         unsigned long timeout = 0;
2768         int ret = 0;
2769
2770         sb = elr->lr_super;
2771         ngroups = EXT4_SB(sb)->s_groups_count;
2772
2773         for (group = elr->lr_next_group; group < ngroups; group++) {
2774                 gdp = ext4_get_group_desc(sb, group, NULL);
2775                 if (!gdp) {
2776                         ret = 1;
2777                         break;
2778                 }
2779
2780                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2781                         break;
2782         }
2783
2784         if (group == ngroups)
2785                 ret = 1;
2786
2787         if (!ret) {
2788                 timeout = jiffies;
2789                 ret = ext4_init_inode_table(sb, group,
2790                                             elr->lr_timeout ? 0 : 1);
2791                 if (elr->lr_timeout == 0) {
2792                         timeout = (jiffies - timeout) *
2793                                   elr->lr_sbi->s_li_wait_mult;
2794                         elr->lr_timeout = timeout;
2795                 }
2796                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2797                 elr->lr_next_group = group + 1;
2798         }
2799
2800         return ret;
2801 }
2802
2803 /*
2804  * Remove lr_request from the list_request and free the
2805  * request structure. Should be called with li_list_mtx held
2806  */
2807 static void ext4_remove_li_request(struct ext4_li_request *elr)
2808 {
2809         struct ext4_sb_info *sbi;
2810
2811         if (!elr)
2812                 return;
2813
2814         sbi = elr->lr_sbi;
2815
2816         list_del(&elr->lr_request);
2817         sbi->s_li_request = NULL;
2818         kfree(elr);
2819 }
2820
2821 static void ext4_unregister_li_request(struct super_block *sb)
2822 {
2823         mutex_lock(&ext4_li_mtx);
2824         if (!ext4_li_info) {
2825                 mutex_unlock(&ext4_li_mtx);
2826                 return;
2827         }
2828
2829         mutex_lock(&ext4_li_info->li_list_mtx);
2830         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2831         mutex_unlock(&ext4_li_info->li_list_mtx);
2832         mutex_unlock(&ext4_li_mtx);
2833 }
2834
2835 static struct task_struct *ext4_lazyinit_task;
2836
2837 /*
2838  * This is the function where ext4lazyinit thread lives. It walks
2839  * through the request list searching for next scheduled filesystem.
2840  * When such a fs is found, run the lazy initialization request
2841  * (ext4_rn_li_request) and keep track of the time spend in this
2842  * function. Based on that time we compute next schedule time of
2843  * the request. When walking through the list is complete, compute
2844  * next waking time and put itself into sleep.
2845  */
2846 static int ext4_lazyinit_thread(void *arg)
2847 {
2848         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2849         struct list_head *pos, *n;
2850         struct ext4_li_request *elr;
2851         unsigned long next_wakeup, cur;
2852
2853         BUG_ON(NULL == eli);
2854
2855 cont_thread:
2856         while (true) {
2857                 next_wakeup = MAX_JIFFY_OFFSET;
2858
2859                 mutex_lock(&eli->li_list_mtx);
2860                 if (list_empty(&eli->li_request_list)) {
2861                         mutex_unlock(&eli->li_list_mtx);
2862                         goto exit_thread;
2863                 }
2864
2865                 list_for_each_safe(pos, n, &eli->li_request_list) {
2866                         elr = list_entry(pos, struct ext4_li_request,
2867                                          lr_request);
2868
2869                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2870                                 if (ext4_run_li_request(elr) != 0) {
2871                                         /* error, remove the lazy_init job */
2872                                         ext4_remove_li_request(elr);
2873                                         continue;
2874                                 }
2875                         }
2876
2877                         if (time_before(elr->lr_next_sched, next_wakeup))
2878                                 next_wakeup = elr->lr_next_sched;
2879                 }
2880                 mutex_unlock(&eli->li_list_mtx);
2881
2882                 if (freezing(current))
2883                         refrigerator();
2884
2885                 cur = jiffies;
2886                 if ((time_after_eq(cur, next_wakeup)) ||
2887                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2888                         cond_resched();
2889                         continue;
2890                 }
2891
2892                 schedule_timeout_interruptible(next_wakeup - cur);
2893
2894                 if (kthread_should_stop()) {
2895                         ext4_clear_request_list();
2896                         goto exit_thread;
2897                 }
2898         }
2899
2900 exit_thread:
2901         /*
2902          * It looks like the request list is empty, but we need
2903          * to check it under the li_list_mtx lock, to prevent any
2904          * additions into it, and of course we should lock ext4_li_mtx
2905          * to atomically free the list and ext4_li_info, because at
2906          * this point another ext4 filesystem could be registering
2907          * new one.
2908          */
2909         mutex_lock(&ext4_li_mtx);
2910         mutex_lock(&eli->li_list_mtx);
2911         if (!list_empty(&eli->li_request_list)) {
2912                 mutex_unlock(&eli->li_list_mtx);
2913                 mutex_unlock(&ext4_li_mtx);
2914                 goto cont_thread;
2915         }
2916         mutex_unlock(&eli->li_list_mtx);
2917         kfree(ext4_li_info);
2918         ext4_li_info = NULL;
2919         mutex_unlock(&ext4_li_mtx);
2920
2921         return 0;
2922 }
2923
2924 static void ext4_clear_request_list(void)
2925 {
2926         struct list_head *pos, *n;
2927         struct ext4_li_request *elr;
2928
2929         mutex_lock(&ext4_li_info->li_list_mtx);
2930         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2931                 elr = list_entry(pos, struct ext4_li_request,
2932                                  lr_request);
2933                 ext4_remove_li_request(elr);
2934         }
2935         mutex_unlock(&ext4_li_info->li_list_mtx);
2936 }
2937
2938 static int ext4_run_lazyinit_thread(void)
2939 {
2940         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2941                                          ext4_li_info, "ext4lazyinit");
2942         if (IS_ERR(ext4_lazyinit_task)) {
2943                 int err = PTR_ERR(ext4_lazyinit_task);
2944                 ext4_clear_request_list();
2945                 kfree(ext4_li_info);
2946                 ext4_li_info = NULL;
2947                 printk(KERN_CRIT "EXT4: error %d creating inode table "
2948                                  "initialization thread\n",
2949                                  err);
2950                 return err;
2951         }
2952         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2953         return 0;
2954 }
2955
2956 /*
2957  * Check whether it make sense to run itable init. thread or not.
2958  * If there is at least one uninitialized inode table, return
2959  * corresponding group number, else the loop goes through all
2960  * groups and return total number of groups.
2961  */
2962 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2963 {
2964         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2965         struct ext4_group_desc *gdp = NULL;
2966
2967         for (group = 0; group < ngroups; group++) {
2968                 gdp = ext4_get_group_desc(sb, group, NULL);
2969                 if (!gdp)
2970                         continue;
2971
2972                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2973                         break;
2974         }
2975
2976         return group;
2977 }
2978
2979 static int ext4_li_info_new(void)
2980 {
2981         struct ext4_lazy_init *eli = NULL;
2982
2983         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2984         if (!eli)
2985                 return -ENOMEM;
2986
2987         INIT_LIST_HEAD(&eli->li_request_list);
2988         mutex_init(&eli->li_list_mtx);
2989
2990         eli->li_state |= EXT4_LAZYINIT_QUIT;
2991
2992         ext4_li_info = eli;
2993
2994         return 0;
2995 }
2996
2997 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2998                                             ext4_group_t start)
2999 {
3000         struct ext4_sb_info *sbi = EXT4_SB(sb);
3001         struct ext4_li_request *elr;
3002         unsigned long rnd;
3003
3004         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3005         if (!elr)
3006                 return NULL;
3007
3008         elr->lr_super = sb;
3009         elr->lr_sbi = sbi;
3010         elr->lr_next_group = start;
3011
3012         /*
3013          * Randomize first schedule time of the request to
3014          * spread the inode table initialization requests
3015          * better.
3016          */
3017         get_random_bytes(&rnd, sizeof(rnd));
3018         elr->lr_next_sched = jiffies + (unsigned long)rnd %
3019                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
3020
3021         return elr;
3022 }
3023
3024 static int ext4_register_li_request(struct super_block *sb,
3025                                     ext4_group_t first_not_zeroed)
3026 {
3027         struct ext4_sb_info *sbi = EXT4_SB(sb);
3028         struct ext4_li_request *elr;
3029         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3030         int ret = 0;
3031
3032         if (sbi->s_li_request != NULL) {
3033                 /*
3034                  * Reset timeout so it can be computed again, because
3035                  * s_li_wait_mult might have changed.
3036                  */
3037                 sbi->s_li_request->lr_timeout = 0;
3038                 return 0;
3039         }
3040
3041         if (first_not_zeroed == ngroups ||
3042             (sb->s_flags & MS_RDONLY) ||
3043             !test_opt(sb, INIT_INODE_TABLE))
3044                 return 0;
3045
3046         elr = ext4_li_request_new(sb, first_not_zeroed);
3047         if (!elr)
3048                 return -ENOMEM;
3049
3050         mutex_lock(&ext4_li_mtx);
3051
3052         if (NULL == ext4_li_info) {
3053                 ret = ext4_li_info_new();
3054                 if (ret)
3055                         goto out;
3056         }
3057
3058         mutex_lock(&ext4_li_info->li_list_mtx);
3059         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3060         mutex_unlock(&ext4_li_info->li_list_mtx);
3061
3062         sbi->s_li_request = elr;
3063         /*
3064          * set elr to NULL here since it has been inserted to
3065          * the request_list and the removal and free of it is
3066          * handled by ext4_clear_request_list from now on.
3067          */
3068         elr = NULL;
3069
3070         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3071                 ret = ext4_run_lazyinit_thread();
3072                 if (ret)
3073                         goto out;
3074         }
3075 out:
3076         mutex_unlock(&ext4_li_mtx);
3077         if (ret)
3078                 kfree(elr);
3079         return ret;
3080 }
3081
3082 /*
3083  * We do not need to lock anything since this is called on
3084  * module unload.
3085  */
3086 static void ext4_destroy_lazyinit_thread(void)
3087 {
3088         /*
3089          * If thread exited earlier
3090          * there's nothing to be done.
3091          */
3092         if (!ext4_li_info || !ext4_lazyinit_task)
3093                 return;
3094
3095         kthread_stop(ext4_lazyinit_task);
3096 }
3097
3098 /*
3099  * Note: calculating the overhead so we can be compatible with
3100  * historical BSD practice is quite difficult in the face of
3101  * clusters/bigalloc.  This is because multiple metadata blocks from
3102  * different block group can end up in the same allocation cluster.
3103  * Calculating the exact overhead in the face of clustered allocation
3104  * requires either O(all block bitmaps) in memory or O(number of block
3105  * groups**2) in time.  We will still calculate the superblock for
3106  * older file systems --- and if we come across with a bigalloc file
3107  * system with zero in s_overhead_clusters the estimate will be close to
3108  * correct especially for very large cluster sizes --- but for newer
3109  * file systems, it's better to calculate this figure once at mkfs
3110  * time, and store it in the superblock.  If the superblock value is
3111  * present (even for non-bigalloc file systems), we will use it.
3112  */
3113 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3114                           char *buf)
3115 {
3116         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3117         struct ext4_group_desc  *gdp;
3118         ext4_fsblk_t            first_block, last_block, b;
3119         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3120         int                     s, j, count = 0;
3121
3122         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC))
3123                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3124                         sbi->s_itb_per_group + 2);
3125
3126         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3127                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3128         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3129         for (i = 0; i < ngroups; i++) {
3130                 gdp = ext4_get_group_desc(sb, i, NULL);
3131                 b = ext4_block_bitmap(sb, gdp);
3132                 if (b >= first_block && b <= last_block) {
3133                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3134                         count++;
3135                 }
3136                 b = ext4_inode_bitmap(sb, gdp);
3137                 if (b >= first_block && b <= last_block) {
3138                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3139                         count++;
3140                 }
3141                 b = ext4_inode_table(sb, gdp);
3142                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3143                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3144                                 int c = EXT4_B2C(sbi, b - first_block);
3145                                 ext4_set_bit(c, buf);
3146                                 count++;
3147                         }
3148                 if (i != grp)
3149                         continue;
3150                 s = 0;
3151                 if (ext4_bg_has_super(sb, grp)) {
3152                         ext4_set_bit(s++, buf);
3153                         count++;
3154                 }
3155                 for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3156                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3157                         count++;
3158                 }
3159         }
3160         if (!count)
3161                 return 0;
3162         return EXT4_CLUSTERS_PER_GROUP(sb) -
3163                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3164 }
3165
3166 /*
3167  * Compute the overhead and stash it in sbi->s_overhead
3168  */
3169 int ext4_calculate_overhead(struct super_block *sb)
3170 {
3171         struct ext4_sb_info *sbi = EXT4_SB(sb);
3172         struct ext4_super_block *es = sbi->s_es;
3173         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3174         ext4_fsblk_t overhead = 0;
3175         char *buf = (char *) get_zeroed_page(GFP_KERNEL);
3176
3177         memset(buf, 0, PAGE_SIZE);
3178         if (!buf)
3179                 return -ENOMEM;
3180
3181         /*
3182          * Compute the overhead (FS structures).  This is constant
3183          * for a given filesystem unless the number of block groups
3184          * changes so we cache the previous value until it does.
3185          */
3186
3187         /*
3188          * All of the blocks before first_data_block are overhead
3189          */
3190         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3191
3192         /*
3193          * Add the overhead found in each block group
3194          */
3195         for (i = 0; i < ngroups; i++) {
3196                 int blks;
3197
3198                 blks = count_overhead(sb, i, buf);
3199                 overhead += blks;
3200                 if (blks)
3201                         memset(buf, 0, PAGE_SIZE);
3202                 cond_resched();
3203         }
3204         sbi->s_overhead = overhead;
3205         smp_wmb();
3206         free_page((unsigned long) buf);
3207         return 0;
3208 }
3209
3210 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3211 {
3212         char *orig_data = kstrdup(data, GFP_KERNEL);
3213         struct buffer_head *bh;
3214         struct ext4_super_block *es = NULL;
3215         struct ext4_sb_info *sbi;
3216         ext4_fsblk_t block;
3217         ext4_fsblk_t sb_block = get_sb_block(&data);
3218         ext4_fsblk_t logical_sb_block;
3219         unsigned long offset = 0;
3220         unsigned long journal_devnum = 0;
3221         unsigned long def_mount_opts;
3222         struct inode *root;
3223         char *cp;
3224         const char *descr;
3225         int ret = -ENOMEM;
3226         int blocksize, clustersize;
3227         unsigned int db_count;
3228         unsigned int i;
3229         int needs_recovery, has_huge_files, has_bigalloc;
3230         __u64 blocks_count;
3231         int err;
3232         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3233         ext4_group_t first_not_zeroed;
3234
3235         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3236         if (!sbi)
3237                 goto out_free_orig;
3238
3239         sbi->s_blockgroup_lock =
3240                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3241         if (!sbi->s_blockgroup_lock) {
3242                 kfree(sbi);
3243                 goto out_free_orig;
3244         }
3245         sb->s_fs_info = sbi;
3246         sbi->s_mount_opt = 0;
3247         sbi->s_resuid = EXT4_DEF_RESUID;
3248         sbi->s_resgid = EXT4_DEF_RESGID;
3249         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3250         sbi->s_sb_block = sb_block;
3251         if (sb->s_bdev->bd_part)
3252                 sbi->s_sectors_written_start =
3253                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3254
3255         /* Cleanup superblock name */
3256         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3257                 *cp = '!';
3258
3259         ret = -EINVAL;
3260         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3261         if (!blocksize) {
3262                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3263                 goto out_fail;
3264         }
3265
3266         /*
3267          * The ext4 superblock will not be buffer aligned for other than 1kB
3268          * block sizes.  We need to calculate the offset from buffer start.
3269          */
3270         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3271                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3272                 offset = do_div(logical_sb_block, blocksize);
3273         } else {
3274                 logical_sb_block = sb_block;
3275         }
3276
3277         if (!(bh = sb_bread(sb, logical_sb_block))) {
3278                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3279                 goto out_fail;
3280         }
3281         /*
3282          * Note: s_es must be initialized as soon as possible because
3283          *       some ext4 macro-instructions depend on its value
3284          */
3285         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3286         sbi->s_es = es;
3287         sb->s_magic = le16_to_cpu(es->s_magic);
3288         if (sb->s_magic != EXT4_SUPER_MAGIC)
3289                 goto cantfind_ext4;
3290         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3291
3292         /* Set defaults before we parse the mount options */
3293         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3294         set_opt(sb, INIT_INODE_TABLE);
3295         if (def_mount_opts & EXT4_DEFM_DEBUG)
3296                 set_opt(sb, DEBUG);
3297         if (def_mount_opts & EXT4_DEFM_BSDGROUPS) {
3298                 ext4_msg(sb, KERN_WARNING, deprecated_msg, "bsdgroups",
3299                         "2.6.38");
3300                 set_opt(sb, GRPID);
3301         }
3302         if (def_mount_opts & EXT4_DEFM_UID16)
3303                 set_opt(sb, NO_UID32);
3304         /* xattr user namespace & acls are now defaulted on */
3305 #ifdef CONFIG_EXT4_FS_XATTR
3306         set_opt(sb, XATTR_USER);
3307 #endif
3308 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3309         set_opt(sb, POSIX_ACL);
3310 #endif
3311         set_opt(sb, MBLK_IO_SUBMIT);
3312         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3313                 set_opt(sb, JOURNAL_DATA);
3314         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3315                 set_opt(sb, ORDERED_DATA);
3316         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3317                 set_opt(sb, WRITEBACK_DATA);
3318
3319         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3320                 set_opt(sb, ERRORS_PANIC);
3321         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3322                 set_opt(sb, ERRORS_CONT);
3323         else
3324                 set_opt(sb, ERRORS_RO);
3325         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3326                 set_opt(sb, BLOCK_VALIDITY);
3327         if (def_mount_opts & EXT4_DEFM_DISCARD)
3328                 set_opt(sb, DISCARD);
3329
3330         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
3331         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
3332         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3333         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3334         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3335
3336         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3337                 set_opt(sb, BARRIER);
3338
3339         /*
3340          * enable delayed allocation by default
3341          * Use -o nodelalloc to turn it off
3342          */
3343         if (!IS_EXT3_SB(sb) &&
3344             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3345                 set_opt(sb, DELALLOC);
3346
3347         /*
3348          * set default s_li_wait_mult for lazyinit, for the case there is
3349          * no mount option specified.
3350          */
3351         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3352
3353         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3354                            &journal_devnum, &journal_ioprio, NULL, 0)) {
3355                 ext4_msg(sb, KERN_WARNING,
3356                          "failed to parse options in superblock: %s",
3357                          sbi->s_es->s_mount_opts);
3358         }
3359         if (!parse_options((char *) data, sb, &journal_devnum,
3360                            &journal_ioprio, NULL, 0))
3361                 goto failed_mount;
3362
3363         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3364                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3365                             "with data=journal disables delayed "
3366                             "allocation and O_DIRECT support!\n");
3367                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3368                         ext4_msg(sb, KERN_ERR, "can't mount with "
3369                                  "both data=journal and delalloc");
3370                         goto failed_mount;
3371                 }
3372                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3373                         ext4_msg(sb, KERN_ERR, "can't mount with "
3374                                  "both data=journal and dioread_nolock");
3375                         goto failed_mount;
3376                 }
3377                 if (test_opt(sb, DELALLOC))
3378                         clear_opt(sb, DELALLOC);
3379         }
3380
3381         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3382                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3383
3384         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3385             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3386              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3387              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3388                 ext4_msg(sb, KERN_WARNING,
3389                        "feature flags set on rev 0 fs, "
3390                        "running e2fsck is recommended");
3391
3392         if (IS_EXT2_SB(sb)) {
3393                 if (ext2_feature_set_ok(sb))
3394                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3395                                  "using the ext4 subsystem");
3396                 else {
3397                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3398                                  "to feature incompatibilities");
3399                         goto failed_mount;
3400                 }
3401         }
3402
3403         if (IS_EXT3_SB(sb)) {
3404                 if (ext3_feature_set_ok(sb))
3405                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3406                                  "using the ext4 subsystem");
3407                 else {
3408                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3409                                  "to feature incompatibilities");
3410                         goto failed_mount;
3411                 }
3412         }
3413
3414         /*
3415          * Check feature flags regardless of the revision level, since we
3416          * previously didn't change the revision level when setting the flags,
3417          * so there is a chance incompat flags are set on a rev 0 filesystem.
3418          */
3419         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3420                 goto failed_mount;
3421
3422         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3423         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3424             blocksize > EXT4_MAX_BLOCK_SIZE) {
3425                 ext4_msg(sb, KERN_ERR,
3426                        "Unsupported filesystem blocksize %d", blocksize);
3427                 goto failed_mount;
3428         }
3429
3430         if (sb->s_blocksize != blocksize) {
3431                 /* Validate the filesystem blocksize */
3432                 if (!sb_set_blocksize(sb, blocksize)) {
3433                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3434                                         blocksize);
3435                         goto failed_mount;
3436                 }
3437
3438                 brelse(bh);
3439                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3440                 offset = do_div(logical_sb_block, blocksize);
3441                 bh = sb_bread(sb, logical_sb_block);
3442                 if (!bh) {
3443                         ext4_msg(sb, KERN_ERR,
3444                                "Can't read superblock on 2nd try");
3445                         goto failed_mount;
3446                 }
3447                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
3448                 sbi->s_es = es;
3449                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3450                         ext4_msg(sb, KERN_ERR,
3451                                "Magic mismatch, very weird!");
3452                         goto failed_mount;
3453                 }
3454         }
3455
3456         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3457                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3458         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3459                                                       has_huge_files);
3460         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3461
3462         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3463                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3464                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3465         } else {
3466                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3467                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3468                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3469                     (!is_power_of_2(sbi->s_inode_size)) ||
3470                     (sbi->s_inode_size > blocksize)) {
3471                         ext4_msg(sb, KERN_ERR,
3472                                "unsupported inode size: %d",
3473                                sbi->s_inode_size);
3474                         goto failed_mount;
3475                 }
3476                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3477                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3478         }
3479
3480         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3481         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3482                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3483                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3484                     !is_power_of_2(sbi->s_desc_size)) {
3485                         ext4_msg(sb, KERN_ERR,
3486                                "unsupported descriptor size %lu",
3487                                sbi->s_desc_size);
3488                         goto failed_mount;
3489                 }
3490         } else
3491                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3492
3493         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3494         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3495         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3496                 goto cantfind_ext4;
3497
3498         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3499         if (sbi->s_inodes_per_block == 0)
3500                 goto cantfind_ext4;
3501         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3502                                         sbi->s_inodes_per_block;
3503         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3504         sbi->s_sbh = bh;
3505         sbi->s_mount_state = le16_to_cpu(es->s_state);
3506         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3507         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3508
3509         for (i = 0; i < 4; i++)
3510                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3511         sbi->s_def_hash_version = es->s_def_hash_version;
3512         i = le32_to_cpu(es->s_flags);
3513         if (i & EXT2_FLAGS_UNSIGNED_HASH)
3514                 sbi->s_hash_unsigned = 3;
3515         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3516 #ifdef __CHAR_UNSIGNED__
3517                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3518                 sbi->s_hash_unsigned = 3;
3519 #else
3520                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3521 #endif
3522                 sb->s_dirt = 1;
3523         }
3524
3525         /* Handle clustersize */
3526         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3527         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3528                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3529         if (has_bigalloc) {
3530                 if (clustersize < blocksize) {
3531                         ext4_msg(sb, KERN_ERR,
3532                                  "cluster size (%d) smaller than "
3533                                  "block size (%d)", clustersize, blocksize);
3534                         goto failed_mount;
3535                 }
3536                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3537                         le32_to_cpu(es->s_log_block_size);
3538                 sbi->s_clusters_per_group =
3539                         le32_to_cpu(es->s_clusters_per_group);
3540                 if (sbi->s_clusters_per_group > blocksize * 8) {
3541                         ext4_msg(sb, KERN_ERR,
3542                                  "#clusters per group too big: %lu",
3543                                  sbi->s_clusters_per_group);
3544                         goto failed_mount;
3545                 }
3546                 if (sbi->s_blocks_per_group !=
3547                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3548                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3549                                  "clusters per group (%lu) inconsistent",
3550                                  sbi->s_blocks_per_group,
3551                                  sbi->s_clusters_per_group);
3552                         goto failed_mount;
3553                 }
3554         } else {
3555                 if (clustersize != blocksize) {
3556                         ext4_warning(sb, "fragment/cluster size (%d) != "
3557                                      "block size (%d)", clustersize,
3558                                      blocksize);
3559                         clustersize = blocksize;
3560                 }
3561                 if (sbi->s_blocks_per_group > blocksize * 8) {
3562                         ext4_msg(sb, KERN_ERR,
3563                                  "#blocks per group too big: %lu",
3564                                  sbi->s_blocks_per_group);
3565                         goto failed_mount;
3566                 }
3567                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3568                 sbi->s_cluster_bits = 0;
3569         }
3570         sbi->s_cluster_ratio = clustersize / blocksize;
3571
3572         if (sbi->s_inodes_per_group > blocksize * 8) {
3573                 ext4_msg(sb, KERN_ERR,
3574                        "#inodes per group too big: %lu",
3575                        sbi->s_inodes_per_group);
3576                 goto failed_mount;
3577         }
3578
3579         /*
3580          * Test whether we have more sectors than will fit in sector_t,
3581          * and whether the max offset is addressable by the page cache.
3582          */
3583         err = generic_check_addressable(sb->s_blocksize_bits,
3584                                         ext4_blocks_count(es));
3585         if (err) {
3586                 ext4_msg(sb, KERN_ERR, "filesystem"
3587                          " too large to mount safely on this system");
3588                 if (sizeof(sector_t) < 8)
3589                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3590                 ret = err;
3591                 goto failed_mount;
3592         }
3593
3594         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3595                 goto cantfind_ext4;
3596
3597         /* check blocks count against device size */
3598         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3599         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3600                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3601                        "exceeds size of device (%llu blocks)",
3602                        ext4_blocks_count(es), blocks_count);
3603                 goto failed_mount;
3604         }
3605
3606         /*
3607          * It makes no sense for the first data block to be beyond the end
3608          * of the filesystem.
3609          */
3610         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3611                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
3612                          "block %u is beyond end of filesystem (%llu)",
3613                          le32_to_cpu(es->s_first_data_block),
3614                          ext4_blocks_count(es));
3615                 goto failed_mount;
3616         }
3617         blocks_count = (ext4_blocks_count(es) -
3618                         le32_to_cpu(es->s_first_data_block) +
3619                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3620         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3621         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3622                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3623                        "(block count %llu, first data block %u, "
3624                        "blocks per group %lu)", sbi->s_groups_count,
3625                        ext4_blocks_count(es),
3626                        le32_to_cpu(es->s_first_data_block),
3627                        EXT4_BLOCKS_PER_GROUP(sb));
3628                 goto failed_mount;
3629         }
3630         sbi->s_groups_count = blocks_count;
3631         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3632                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3633         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3634                    EXT4_DESC_PER_BLOCK(sb);
3635         sbi->s_group_desc = ext4_kvmalloc(db_count *
3636                                           sizeof(struct buffer_head *),
3637                                           GFP_KERNEL);
3638         if (sbi->s_group_desc == NULL) {
3639                 ext4_msg(sb, KERN_ERR, "not enough memory");
3640                 goto failed_mount;
3641         }
3642
3643         if (ext4_proc_root)
3644                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3645
3646         bgl_lock_init(sbi->s_blockgroup_lock);
3647
3648         for (i = 0; i < db_count; i++) {
3649                 block = descriptor_loc(sb, logical_sb_block, i);
3650                 sbi->s_group_desc[i] = sb_bread(sb, block);
3651                 if (!sbi->s_group_desc[i]) {
3652                         ext4_msg(sb, KERN_ERR,
3653                                "can't read group descriptor %d", i);
3654                         db_count = i;
3655                         goto failed_mount2;
3656                 }
3657         }
3658         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3659                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3660                 goto failed_mount2;
3661         }
3662         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3663                 if (!ext4_fill_flex_info(sb)) {
3664                         ext4_msg(sb, KERN_ERR,
3665                                "unable to initialize "
3666                                "flex_bg meta info!");
3667                         goto failed_mount2;
3668                 }
3669
3670         sbi->s_gdb_count = db_count;
3671         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3672         spin_lock_init(&sbi->s_next_gen_lock);
3673
3674         init_timer(&sbi->s_err_report);
3675         sbi->s_err_report.function = print_daily_error_info;
3676         sbi->s_err_report.data = (unsigned long) sb;
3677
3678         err = percpu_counter_init(&sbi->s_freeclusters_counter,
3679                         ext4_count_free_clusters(sb));
3680         if (!err) {
3681                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
3682                                 ext4_count_free_inodes(sb));
3683         }
3684         if (!err) {
3685                 err = percpu_counter_init(&sbi->s_dirs_counter,
3686                                 ext4_count_dirs(sb));
3687         }
3688         if (!err) {
3689                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0);
3690         }
3691         if (err) {
3692                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3693                 goto failed_mount3;
3694         }
3695
3696         sbi->s_stripe = ext4_get_stripe_size(sbi);
3697         sbi->s_max_writeback_mb_bump = 128;
3698
3699         /*
3700          * set up enough so that it can read an inode
3701          */
3702         if (!test_opt(sb, NOLOAD) &&
3703             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3704                 sb->s_op = &ext4_sops;
3705         else
3706                 sb->s_op = &ext4_nojournal_sops;
3707         sb->s_export_op = &ext4_export_ops;
3708         sb->s_xattr = ext4_xattr_handlers;
3709 #ifdef CONFIG_QUOTA
3710         sb->s_qcop = &ext4_qctl_operations;
3711         sb->dq_op = &ext4_quota_operations;
3712 #endif
3713         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3714
3715         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3716         mutex_init(&sbi->s_orphan_lock);
3717         sbi->s_resize_flags = 0;
3718
3719         sb->s_root = NULL;
3720
3721         needs_recovery = (es->s_last_orphan != 0 ||
3722                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3723                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3724
3725         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3726             !(sb->s_flags & MS_RDONLY))
3727                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3728                         goto failed_mount3;
3729
3730         /*
3731          * The first inode we look at is the journal inode.  Don't try
3732          * root first: it may be modified in the journal!
3733          */
3734         if (!test_opt(sb, NOLOAD) &&
3735             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3736                 if (ext4_load_journal(sb, es, journal_devnum))
3737                         goto failed_mount3;
3738         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3739               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3740                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3741                        "suppressed and not mounted read-only");
3742                 goto failed_mount_wq;
3743         } else {
3744                 clear_opt(sb, DATA_FLAGS);
3745                 sbi->s_journal = NULL;
3746                 needs_recovery = 0;
3747                 goto no_journal;
3748         }
3749
3750         if (ext4_blocks_count(es) > 0xffffffffULL &&
3751             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3752                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3753                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3754                 goto failed_mount_wq;
3755         }
3756
3757         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3758                 jbd2_journal_set_features(sbi->s_journal,
3759                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3760                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3761         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3762                 jbd2_journal_set_features(sbi->s_journal,
3763                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
3764                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3765                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3766         } else {
3767                 jbd2_journal_clear_features(sbi->s_journal,
3768                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3769                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3770         }
3771
3772         /* We have now updated the journal if required, so we can
3773          * validate the data journaling mode. */
3774         switch (test_opt(sb, DATA_FLAGS)) {
3775         case 0:
3776                 /* No mode set, assume a default based on the journal
3777                  * capabilities: ORDERED_DATA if the journal can
3778                  * cope, else JOURNAL_DATA
3779                  */
3780                 if (jbd2_journal_check_available_features
3781                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3782                         set_opt(sb, ORDERED_DATA);
3783                 else
3784                         set_opt(sb, JOURNAL_DATA);
3785                 break;
3786
3787         case EXT4_MOUNT_ORDERED_DATA:
3788         case EXT4_MOUNT_WRITEBACK_DATA:
3789                 if (!jbd2_journal_check_available_features
3790                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3791                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3792                                "requested data journaling mode");
3793                         goto failed_mount_wq;
3794                 }
3795         default:
3796                 break;
3797         }
3798         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3799
3800         /*
3801          * The journal may have updated the bg summary counts, so we
3802          * need to update the global counters.
3803          */
3804         percpu_counter_set(&sbi->s_freeclusters_counter,
3805                            ext4_count_free_clusters(sb));
3806         percpu_counter_set(&sbi->s_freeinodes_counter,
3807                            ext4_count_free_inodes(sb));
3808         percpu_counter_set(&sbi->s_dirs_counter,
3809                            ext4_count_dirs(sb));
3810         percpu_counter_set(&sbi->s_dirtyclusters_counter, 0);
3811
3812 no_journal:
3813         /*
3814          * Get the # of file system overhead blocks from the
3815          * superblock if present.
3816          */
3817         if (es->s_overhead_clusters)
3818                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
3819         else {
3820                 ret = ext4_calculate_overhead(sb);
3821                 if (ret)
3822                         goto failed_mount_wq;
3823         }
3824
3825         /*
3826          * The maximum number of concurrent works can be high and
3827          * concurrency isn't really necessary.  Limit it to 1.
3828          */
3829         EXT4_SB(sb)->dio_unwritten_wq =
3830                 alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
3831         if (!EXT4_SB(sb)->dio_unwritten_wq) {
3832                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
3833                 goto failed_mount_wq;
3834         }
3835
3836         /*
3837          * The jbd2_journal_load will have done any necessary log recovery,
3838          * so we can safely mount the rest of the filesystem now.
3839          */
3840
3841         root = ext4_iget(sb, EXT4_ROOT_INO);
3842         if (IS_ERR(root)) {
3843                 ext4_msg(sb, KERN_ERR, "get root inode failed");
3844                 ret = PTR_ERR(root);
3845                 root = NULL;
3846                 goto failed_mount4;
3847         }
3848         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3849                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3850                 goto failed_mount4;
3851         }
3852         sb->s_root = d_alloc_root(root);
3853         if (!sb->s_root) {
3854                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
3855                 ret = -ENOMEM;
3856                 goto failed_mount4;
3857         }
3858
3859         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
3860                 sb->s_flags |= MS_RDONLY;
3861
3862         /* determine the minimum size of new large inodes, if present */
3863         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3864                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3865                                                      EXT4_GOOD_OLD_INODE_SIZE;
3866                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3867                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
3868                         if (sbi->s_want_extra_isize <
3869                             le16_to_cpu(es->s_want_extra_isize))
3870                                 sbi->s_want_extra_isize =
3871                                         le16_to_cpu(es->s_want_extra_isize);
3872                         if (sbi->s_want_extra_isize <
3873                             le16_to_cpu(es->s_min_extra_isize))
3874                                 sbi->s_want_extra_isize =
3875                                         le16_to_cpu(es->s_min_extra_isize);
3876                 }
3877         }
3878         /* Check if enough inode space is available */
3879         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3880                                                         sbi->s_inode_size) {
3881                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3882                                                        EXT4_GOOD_OLD_INODE_SIZE;
3883                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
3884                          "available");
3885         }
3886
3887         err = ext4_setup_system_zone(sb);
3888         if (err) {
3889                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3890                          "zone (%d)", err);
3891                 goto failed_mount4;
3892         }
3893
3894         ext4_ext_init(sb);
3895         err = ext4_mb_init(sb, needs_recovery);
3896         if (err) {
3897                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3898                          err);
3899                 goto failed_mount5;
3900         }
3901
3902         err = ext4_register_li_request(sb, first_not_zeroed);
3903         if (err)
3904                 goto failed_mount6;
3905
3906         sbi->s_kobj.kset = ext4_kset;
3907         init_completion(&sbi->s_kobj_unregister);
3908         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3909                                    "%s", sb->s_id);
3910         if (err)
3911                 goto failed_mount7;
3912
3913         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3914         ext4_orphan_cleanup(sb, es);
3915         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3916         if (needs_recovery) {
3917                 ext4_msg(sb, KERN_INFO, "recovery complete");
3918                 ext4_mark_recovery_complete(sb, es);
3919         }
3920         if (EXT4_SB(sb)->s_journal) {
3921                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3922                         descr = " journalled data mode";
3923                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3924                         descr = " ordered data mode";
3925                 else
3926                         descr = " writeback data mode";
3927         } else
3928                 descr = "out journal";
3929
3930         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3931                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
3932                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
3933
3934         if (es->s_error_count)
3935                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
3936
3937         kfree(orig_data);
3938         return 0;
3939
3940 cantfind_ext4:
3941         if (!silent)
3942                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3943         goto failed_mount;
3944
3945 failed_mount7:
3946         ext4_unregister_li_request(sb);
3947 failed_mount6:
3948         ext4_ext_release(sb);
3949 failed_mount5:
3950         ext4_mb_release(sb);
3951         ext4_release_system_zone(sb);
3952 failed_mount4:
3953         iput(root);
3954         sb->s_root = NULL;
3955         ext4_msg(sb, KERN_ERR, "mount failed");
3956         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
3957 failed_mount_wq:
3958         if (sbi->s_journal) {
3959                 jbd2_journal_destroy(sbi->s_journal);
3960                 sbi->s_journal = NULL;
3961         }
3962 failed_mount3:
3963         del_timer_sync(&sbi->s_err_report);
3964         if (sbi->s_flex_groups)
3965                 ext4_kvfree(sbi->s_flex_groups);
3966         percpu_counter_destroy(&sbi->s_freeclusters_counter);
3967         percpu_counter_destroy(&sbi->s_freeinodes_counter);
3968         percpu_counter_destroy(&sbi->s_dirs_counter);
3969         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
3970         if (sbi->s_mmp_tsk)
3971                 kthread_stop(sbi->s_mmp_tsk);
3972 failed_mount2:
3973         for (i = 0; i < db_count; i++)
3974                 brelse(sbi->s_group_desc[i]);
3975         ext4_kvfree(sbi->s_group_desc);
3976 failed_mount:
3977         if (sbi->s_proc) {
3978                 remove_proc_entry(sb->s_id, ext4_proc_root);
3979         }
3980 #ifdef CONFIG_QUOTA
3981         for (i = 0; i < MAXQUOTAS; i++)
3982                 kfree(sbi->s_qf_names[i]);
3983 #endif
3984         ext4_blkdev_remove(sbi);
3985         brelse(bh);
3986 out_fail:
3987         sb->s_fs_info = NULL;
3988         kfree(sbi->s_blockgroup_lock);
3989         kfree(sbi);
3990 out_free_orig:
3991         kfree(orig_data);
3992         return ret;
3993 }
3994
3995 /*
3996  * Setup any per-fs journal parameters now.  We'll do this both on
3997  * initial mount, once the journal has been initialised but before we've
3998  * done any recovery; and again on any subsequent remount.
3999  */
4000 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4001 {
4002         struct ext4_sb_info *sbi = EXT4_SB(sb);
4003
4004         journal->j_commit_interval = sbi->s_commit_interval;
4005         journal->j_min_batch_time = sbi->s_min_batch_time;
4006         journal->j_max_batch_time = sbi->s_max_batch_time;
4007
4008         write_lock(&journal->j_state_lock);
4009         if (test_opt(sb, BARRIER))
4010                 journal->j_flags |= JBD2_BARRIER;
4011         else
4012                 journal->j_flags &= ~JBD2_BARRIER;
4013         if (test_opt(sb, DATA_ERR_ABORT))
4014                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4015         else
4016                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4017         write_unlock(&journal->j_state_lock);
4018 }
4019
4020 static journal_t *ext4_get_journal(struct super_block *sb,
4021                                    unsigned int journal_inum)
4022 {
4023         struct inode *journal_inode;
4024         journal_t *journal;
4025
4026         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4027
4028         /* First, test for the existence of a valid inode on disk.  Bad
4029          * things happen if we iget() an unused inode, as the subsequent
4030          * iput() will try to delete it. */
4031
4032         journal_inode = ext4_iget(sb, journal_inum);
4033         if (IS_ERR(journal_inode)) {
4034                 ext4_msg(sb, KERN_ERR, "no journal found");
4035                 return NULL;
4036         }
4037         if (!journal_inode->i_nlink) {
4038                 make_bad_inode(journal_inode);
4039                 iput(journal_inode);
4040                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4041                 return NULL;
4042         }
4043
4044         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4045                   journal_inode, journal_inode->i_size);
4046         if (!S_ISREG(journal_inode->i_mode)) {
4047                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4048                 iput(journal_inode);
4049                 return NULL;
4050         }
4051
4052         journal = jbd2_journal_init_inode(journal_inode);
4053         if (!journal) {
4054                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4055                 iput(journal_inode);
4056                 return NULL;
4057         }
4058         journal->j_private = sb;
4059         ext4_init_journal_params(sb, journal);
4060         return journal;
4061 }
4062
4063 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4064                                        dev_t j_dev)
4065 {
4066         struct buffer_head *bh;
4067         journal_t *journal;
4068         ext4_fsblk_t start;
4069         ext4_fsblk_t len;
4070         int hblock, blocksize;
4071         ext4_fsblk_t sb_block;
4072         unsigned long offset;
4073         struct ext4_super_block *es;
4074         struct block_device *bdev;
4075
4076         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4077
4078         bdev = ext4_blkdev_get(j_dev, sb);
4079         if (bdev == NULL)
4080                 return NULL;
4081
4082         blocksize = sb->s_blocksize;
4083         hblock = bdev_logical_block_size(bdev);
4084         if (blocksize < hblock) {
4085                 ext4_msg(sb, KERN_ERR,
4086                         "blocksize too small for journal device");
4087                 goto out_bdev;
4088         }
4089
4090         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4091         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4092         set_blocksize(bdev, blocksize);
4093         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4094                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4095                        "external journal");
4096                 goto out_bdev;
4097         }
4098
4099         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
4100         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4101             !(le32_to_cpu(es->s_feature_incompat) &
4102               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4103                 ext4_msg(sb, KERN_ERR, "external journal has "
4104                                         "bad superblock");
4105                 brelse(bh);
4106                 goto out_bdev;
4107         }
4108
4109         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4110                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4111                 brelse(bh);
4112                 goto out_bdev;
4113         }
4114
4115         len = ext4_blocks_count(es);
4116         start = sb_block + 1;
4117         brelse(bh);     /* we're done with the superblock */
4118
4119         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4120                                         start, len, blocksize);
4121         if (!journal) {
4122                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4123                 goto out_bdev;
4124         }
4125         journal->j_private = sb;
4126         ll_rw_block(READ, 1, &journal->j_sb_buffer);
4127         wait_on_buffer(journal->j_sb_buffer);
4128         if (!buffer_uptodate(journal->j_sb_buffer)) {
4129                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4130                 goto out_journal;
4131         }
4132         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4133                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4134                                         "user (unsupported) - %d",
4135                         be32_to_cpu(journal->j_superblock->s_nr_users));
4136                 goto out_journal;
4137         }
4138         EXT4_SB(sb)->journal_bdev = bdev;
4139         ext4_init_journal_params(sb, journal);
4140         return journal;
4141
4142 out_journal:
4143         jbd2_journal_destroy(journal);
4144 out_bdev:
4145         ext4_blkdev_put(bdev);
4146         return NULL;
4147 }
4148
4149 static int ext4_load_journal(struct super_block *sb,
4150                              struct ext4_super_block *es,
4151                              unsigned long journal_devnum)
4152 {
4153         journal_t *journal;
4154         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4155         dev_t journal_dev;
4156         int err = 0;
4157         int really_read_only;
4158
4159         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4160
4161         if (journal_devnum &&
4162             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4163                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4164                         "numbers have changed");
4165                 journal_dev = new_decode_dev(journal_devnum);
4166         } else
4167                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4168
4169         really_read_only = bdev_read_only(sb->s_bdev);
4170
4171         /*
4172          * Are we loading a blank journal or performing recovery after a
4173          * crash?  For recovery, we need to check in advance whether we
4174          * can get read-write access to the device.
4175          */
4176         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4177                 if (sb->s_flags & MS_RDONLY) {
4178                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4179                                         "required on readonly filesystem");
4180                         if (really_read_only) {
4181                                 ext4_msg(sb, KERN_ERR, "write access "
4182                                         "unavailable, cannot proceed");
4183                                 return -EROFS;
4184                         }
4185                         ext4_msg(sb, KERN_INFO, "write access will "
4186                                "be enabled during recovery");
4187                 }
4188         }
4189
4190         if (journal_inum && journal_dev) {
4191                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4192                        "and inode journals!");
4193                 return -EINVAL;
4194         }
4195
4196         if (journal_inum) {
4197                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4198                         return -EINVAL;
4199         } else {
4200                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4201                         return -EINVAL;
4202         }
4203
4204         if (!(journal->j_flags & JBD2_BARRIER))
4205                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4206
4207         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
4208                 err = jbd2_journal_update_format(journal);
4209                 if (err)  {
4210                         ext4_msg(sb, KERN_ERR, "error updating journal");
4211                         jbd2_journal_destroy(journal);
4212                         return err;
4213                 }
4214         }
4215
4216         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4217                 err = jbd2_journal_wipe(journal, !really_read_only);
4218         if (!err) {
4219                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4220                 if (save)
4221                         memcpy(save, ((char *) es) +
4222                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4223                 err = jbd2_journal_load(journal);
4224                 if (save)
4225                         memcpy(((char *) es) + EXT4_S_ERR_START,
4226                                save, EXT4_S_ERR_LEN);
4227                 kfree(save);
4228         }
4229
4230         if (err) {
4231                 ext4_msg(sb, KERN_ERR, "error loading journal");
4232                 jbd2_journal_destroy(journal);
4233                 return err;
4234         }
4235
4236         EXT4_SB(sb)->s_journal = journal;
4237         ext4_clear_journal_err(sb, es);
4238
4239         if (!really_read_only && journal_devnum &&
4240             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4241                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4242
4243                 /* Make sure we flush the recovery flag to disk. */
4244                 ext4_commit_super(sb, 1);
4245         }
4246
4247         return 0;
4248 }
4249
4250 static int ext4_commit_super(struct super_block *sb, int sync)
4251 {
4252         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4253         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4254         int error = 0;
4255
4256         if (!sbh || block_device_ejected(sb))
4257                 return error;
4258         if (buffer_write_io_error(sbh)) {
4259                 /*
4260                  * Oh, dear.  A previous attempt to write the
4261                  * superblock failed.  This could happen because the
4262                  * USB device was yanked out.  Or it could happen to
4263                  * be a transient write error and maybe the block will
4264                  * be remapped.  Nothing we can do but to retry the
4265                  * write and hope for the best.
4266                  */
4267                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4268                        "superblock detected");
4269                 clear_buffer_write_io_error(sbh);
4270                 set_buffer_uptodate(sbh);
4271         }
4272         /*
4273          * If the file system is mounted read-only, don't update the
4274          * superblock write time.  This avoids updating the superblock
4275          * write time when we are mounting the root file system
4276          * read/only but we need to replay the journal; at that point,
4277          * for people who are east of GMT and who make their clock
4278          * tick in localtime for Windows bug-for-bug compatibility,
4279          * the clock is set in the future, and this will cause e2fsck
4280          * to complain and force a full file system check.
4281          */
4282         if (!(sb->s_flags & MS_RDONLY))
4283                 es->s_wtime = cpu_to_le32(get_seconds());
4284         if (sb->s_bdev->bd_part)
4285                 es->s_kbytes_written =
4286                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4287                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4288                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4289         else
4290                 es->s_kbytes_written =
4291                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4292         ext4_free_blocks_count_set(es,
4293                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4294                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4295         es->s_free_inodes_count =
4296                 cpu_to_le32(percpu_counter_sum_positive(
4297                                 &EXT4_SB(sb)->s_freeinodes_counter));
4298         sb->s_dirt = 0;
4299         BUFFER_TRACE(sbh, "marking dirty");
4300         mark_buffer_dirty(sbh);
4301         if (sync) {
4302                 error = sync_dirty_buffer(sbh);
4303                 if (error)
4304                         return error;
4305
4306                 error = buffer_write_io_error(sbh);
4307                 if (error) {
4308                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4309                                "superblock");
4310                         clear_buffer_write_io_error(sbh);
4311                         set_buffer_uptodate(sbh);
4312                 }
4313         }
4314         return error;
4315 }
4316
4317 /*
4318  * Have we just finished recovery?  If so, and if we are mounting (or
4319  * remounting) the filesystem readonly, then we will end up with a
4320  * consistent fs on disk.  Record that fact.
4321  */
4322 static void ext4_mark_recovery_complete(struct super_block *sb,
4323                                         struct ext4_super_block *es)
4324 {
4325         journal_t *journal = EXT4_SB(sb)->s_journal;
4326
4327         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4328                 BUG_ON(journal != NULL);
4329                 return;
4330         }
4331         jbd2_journal_lock_updates(journal);
4332         if (jbd2_journal_flush(journal) < 0)
4333                 goto out;
4334
4335         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4336             sb->s_flags & MS_RDONLY) {
4337                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4338                 ext4_commit_super(sb, 1);
4339         }
4340
4341 out:
4342         jbd2_journal_unlock_updates(journal);
4343 }
4344
4345 /*
4346  * If we are mounting (or read-write remounting) a filesystem whose journal
4347  * has recorded an error from a previous lifetime, move that error to the
4348  * main filesystem now.
4349  */
4350 static void ext4_clear_journal_err(struct super_block *sb,
4351                                    struct ext4_super_block *es)
4352 {
4353         journal_t *journal;
4354         int j_errno;
4355         const char *errstr;
4356
4357         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4358
4359         journal = EXT4_SB(sb)->s_journal;
4360
4361         /*
4362          * Now check for any error status which may have been recorded in the
4363          * journal by a prior ext4_error() or ext4_abort()
4364          */
4365
4366         j_errno = jbd2_journal_errno(journal);
4367         if (j_errno) {
4368                 char nbuf[16];
4369
4370                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4371                 ext4_warning(sb, "Filesystem error recorded "
4372                              "from previous mount: %s", errstr);
4373                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4374
4375                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4376                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4377                 ext4_commit_super(sb, 1);
4378
4379                 jbd2_journal_clear_err(journal);
4380         }
4381 }
4382
4383 /*
4384  * Force the running and committing transactions to commit,
4385  * and wait on the commit.
4386  */
4387 int ext4_force_commit(struct super_block *sb)
4388 {
4389         journal_t *journal;
4390         int ret = 0;
4391
4392         if (sb->s_flags & MS_RDONLY)
4393                 return 0;
4394
4395         journal = EXT4_SB(sb)->s_journal;
4396         if (journal) {
4397                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
4398                 ret = ext4_journal_force_commit(journal);
4399         }
4400
4401         return ret;
4402 }
4403
4404 static void ext4_write_super(struct super_block *sb)
4405 {
4406         lock_super(sb);
4407         ext4_commit_super(sb, 1);
4408         unlock_super(sb);
4409 }
4410
4411 static int ext4_sync_fs(struct super_block *sb, int wait)
4412 {
4413         int ret = 0;
4414         tid_t target;
4415         struct ext4_sb_info *sbi = EXT4_SB(sb);
4416
4417         trace_ext4_sync_fs(sb, wait);
4418         flush_workqueue(sbi->dio_unwritten_wq);
4419         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4420                 if (wait)
4421                         jbd2_log_wait_commit(sbi->s_journal, target);
4422         }
4423         return ret;
4424 }
4425
4426 /*
4427  * LVM calls this function before a (read-only) snapshot is created.  This
4428  * gives us a chance to flush the journal completely and mark the fs clean.
4429  *
4430  * Note that only this function cannot bring a filesystem to be in a clean
4431  * state independently, because ext4 prevents a new handle from being started
4432  * by @sb->s_frozen, which stays in an upper layer.  It thus needs help from
4433  * the upper layer.
4434  */
4435 static int ext4_freeze(struct super_block *sb)
4436 {
4437         int error = 0;
4438         journal_t *journal;
4439
4440         if (sb->s_flags & MS_RDONLY)
4441                 return 0;
4442
4443         journal = EXT4_SB(sb)->s_journal;
4444
4445         /* Now we set up the journal barrier. */
4446         jbd2_journal_lock_updates(journal);
4447
4448         /*
4449          * Don't clear the needs_recovery flag if we failed to flush
4450          * the journal.
4451          */
4452         error = jbd2_journal_flush(journal);
4453         if (error < 0)
4454                 goto out;
4455
4456         /* Journal blocked and flushed, clear needs_recovery flag. */
4457         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4458         error = ext4_commit_super(sb, 1);
4459 out:
4460         /* we rely on s_frozen to stop further updates */
4461         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4462         return error;
4463 }
4464
4465 /*
4466  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4467  * flag here, even though the filesystem is not technically dirty yet.
4468  */
4469 static int ext4_unfreeze(struct super_block *sb)
4470 {
4471         if (sb->s_flags & MS_RDONLY)
4472                 return 0;
4473
4474         lock_super(sb);
4475         /* Reset the needs_recovery flag before the fs is unlocked. */
4476         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4477         ext4_commit_super(sb, 1);
4478         unlock_super(sb);
4479         return 0;
4480 }
4481
4482 /*
4483  * Structure to save mount options for ext4_remount's benefit
4484  */
4485 struct ext4_mount_options {
4486         unsigned long s_mount_opt;
4487         unsigned long s_mount_opt2;
4488         uid_t s_resuid;
4489         gid_t s_resgid;
4490         unsigned long s_commit_interval;
4491         u32 s_min_batch_time, s_max_batch_time;
4492 #ifdef CONFIG_QUOTA
4493         int s_jquota_fmt;
4494         char *s_qf_names[MAXQUOTAS];
4495 #endif
4496 };
4497
4498 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4499 {
4500         struct ext4_super_block *es;
4501         struct ext4_sb_info *sbi = EXT4_SB(sb);
4502         ext4_fsblk_t n_blocks_count = 0;
4503         unsigned long old_sb_flags;
4504         struct ext4_mount_options old_opts;
4505         int enable_quota = 0;
4506         ext4_group_t g;
4507         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4508         int err = 0;
4509 #ifdef CONFIG_QUOTA
4510         int i;
4511 #endif
4512         char *orig_data = kstrdup(data, GFP_KERNEL);
4513
4514         /* Store the original options */
4515         lock_super(sb);
4516         old_sb_flags = sb->s_flags;
4517         old_opts.s_mount_opt = sbi->s_mount_opt;
4518         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4519         old_opts.s_resuid = sbi->s_resuid;
4520         old_opts.s_resgid = sbi->s_resgid;
4521         old_opts.s_commit_interval = sbi->s_commit_interval;
4522         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4523         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4524 #ifdef CONFIG_QUOTA
4525         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4526         for (i = 0; i < MAXQUOTAS; i++)
4527                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
4528 #endif
4529         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4530                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4531
4532         /*
4533          * Allow the "check" option to be passed as a remount option.
4534          */
4535         if (!parse_options(data, sb, NULL, &journal_ioprio,
4536                            &n_blocks_count, 1)) {
4537                 err = -EINVAL;
4538                 goto restore_opts;
4539         }
4540
4541         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4542                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4543                         ext4_msg(sb, KERN_ERR, "can't mount with "
4544                                  "both data=journal and delalloc");
4545                         err = -EINVAL;
4546                         goto restore_opts;
4547                 }
4548                 if (test_opt(sb, DIOREAD_NOLOCK)) {
4549                         ext4_msg(sb, KERN_ERR, "can't mount with "
4550                                  "both data=journal and dioread_nolock");
4551                         err = -EINVAL;
4552                         goto restore_opts;
4553                 }
4554         }
4555
4556         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4557                 ext4_abort(sb, "Abort forced by user");
4558
4559         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4560                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4561
4562         es = sbi->s_es;
4563
4564         if (sbi->s_journal) {
4565                 ext4_init_journal_params(sb, sbi->s_journal);
4566                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4567         }
4568
4569         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
4570                 n_blocks_count > ext4_blocks_count(es)) {
4571                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4572                         err = -EROFS;
4573                         goto restore_opts;
4574                 }
4575
4576                 if (*flags & MS_RDONLY) {
4577                         err = dquot_suspend(sb, -1);
4578                         if (err < 0)
4579                                 goto restore_opts;
4580
4581                         /*
4582                          * First of all, the unconditional stuff we have to do
4583                          * to disable replay of the journal when we next remount
4584                          */
4585                         sb->s_flags |= MS_RDONLY;
4586
4587                         /*
4588                          * OK, test if we are remounting a valid rw partition
4589                          * readonly, and if so set the rdonly flag and then
4590                          * mark the partition as valid again.
4591                          */
4592                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4593                             (sbi->s_mount_state & EXT4_VALID_FS))
4594                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4595
4596                         if (sbi->s_journal)
4597                                 ext4_mark_recovery_complete(sb, es);
4598                 } else {
4599                         /* Make sure we can mount this feature set readwrite */
4600                         if (!ext4_feature_set_ok(sb, 0)) {
4601                                 err = -EROFS;
4602                                 goto restore_opts;
4603                         }
4604                         /*
4605                          * Make sure the group descriptor checksums
4606                          * are sane.  If they aren't, refuse to remount r/w.
4607                          */
4608                         for (g = 0; g < sbi->s_groups_count; g++) {
4609                                 struct ext4_group_desc *gdp =
4610                                         ext4_get_group_desc(sb, g, NULL);
4611
4612                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
4613                                         ext4_msg(sb, KERN_ERR,
4614                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4615                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4616                                                le16_to_cpu(gdp->bg_checksum));
4617                                         err = -EINVAL;
4618                                         goto restore_opts;
4619                                 }
4620                         }
4621
4622                         /*
4623                          * If we have an unprocessed orphan list hanging
4624                          * around from a previously readonly bdev mount,
4625                          * require a full umount/remount for now.
4626                          */
4627                         if (es->s_last_orphan) {
4628                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4629                                        "remount RDWR because of unprocessed "
4630                                        "orphan inode list.  Please "
4631                                        "umount/remount instead");
4632                                 err = -EINVAL;
4633                                 goto restore_opts;
4634                         }
4635
4636                         /*
4637                          * Mounting a RDONLY partition read-write, so reread
4638                          * and store the current valid flag.  (It may have
4639                          * been changed by e2fsck since we originally mounted
4640                          * the partition.)
4641                          */
4642                         if (sbi->s_journal)
4643                                 ext4_clear_journal_err(sb, es);
4644                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4645                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
4646                                 goto restore_opts;
4647                         if (!ext4_setup_super(sb, es, 0))
4648                                 sb->s_flags &= ~MS_RDONLY;
4649                         if (EXT4_HAS_INCOMPAT_FEATURE(sb,
4650                                                      EXT4_FEATURE_INCOMPAT_MMP))
4651                                 if (ext4_multi_mount_protect(sb,
4652                                                 le64_to_cpu(es->s_mmp_block))) {
4653                                         err = -EROFS;
4654                                         goto restore_opts;
4655                                 }
4656                         enable_quota = 1;
4657                 }
4658         }
4659
4660         /*
4661          * Reinitialize lazy itable initialization thread based on
4662          * current settings
4663          */
4664         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4665                 ext4_unregister_li_request(sb);
4666         else {
4667                 ext4_group_t first_not_zeroed;
4668                 first_not_zeroed = ext4_has_uninit_itable(sb);
4669                 ext4_register_li_request(sb, first_not_zeroed);
4670         }
4671
4672         ext4_setup_system_zone(sb);
4673         if (sbi->s_journal == NULL && !(old_sb_flags & MS_RDONLY))
4674                 ext4_commit_super(sb, 1);
4675
4676 #ifdef CONFIG_QUOTA
4677         /* Release old quota file names */
4678         for (i = 0; i < MAXQUOTAS; i++)
4679                 if (old_opts.s_qf_names[i] &&
4680                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4681                         kfree(old_opts.s_qf_names[i]);
4682 #endif
4683         unlock_super(sb);
4684         if (enable_quota)
4685                 dquot_resume(sb, -1);
4686
4687         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4688         kfree(orig_data);
4689         return 0;
4690
4691 restore_opts:
4692         sb->s_flags = old_sb_flags;
4693         sbi->s_mount_opt = old_opts.s_mount_opt;
4694         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4695         sbi->s_resuid = old_opts.s_resuid;
4696         sbi->s_resgid = old_opts.s_resgid;
4697         sbi->s_commit_interval = old_opts.s_commit_interval;
4698         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4699         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4700 #ifdef CONFIG_QUOTA
4701         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4702         for (i = 0; i < MAXQUOTAS; i++) {
4703                 if (sbi->s_qf_names[i] &&
4704                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4705                         kfree(sbi->s_qf_names[i]);
4706                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4707         }
4708 #endif
4709         unlock_super(sb);
4710         kfree(orig_data);
4711         return err;
4712 }
4713
4714 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4715 {
4716         struct super_block *sb = dentry->d_sb;
4717         struct ext4_sb_info *sbi = EXT4_SB(sb);
4718         struct ext4_super_block *es = sbi->s_es;
4719         ext4_fsblk_t overhead = 0;
4720         u64 fsid;
4721         s64 bfree;
4722
4723         if (!test_opt(sb, MINIX_DF))
4724                 overhead = sbi->s_overhead;
4725
4726         buf->f_type = EXT4_SUPER_MAGIC;
4727         buf->f_bsize = sb->s_blocksize;
4728         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, sbi->s_overhead);
4729         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
4730                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
4731         /* prevent underflow in case that few free space is available */
4732         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
4733         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
4734         if (buf->f_bfree < ext4_r_blocks_count(es))
4735                 buf->f_bavail = 0;
4736         buf->f_files = le32_to_cpu(es->s_inodes_count);
4737         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4738         buf->f_namelen = EXT4_NAME_LEN;
4739         fsid = le64_to_cpup((void *)es->s_uuid) ^
4740                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4741         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4742         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4743
4744         return 0;
4745 }
4746
4747 /* Helper function for writing quotas on sync - we need to start transaction
4748  * before quota file is locked for write. Otherwise the are possible deadlocks:
4749  * Process 1                         Process 2
4750  * ext4_create()                     quota_sync()
4751  *   jbd2_journal_start()                  write_dquot()
4752  *   dquot_initialize()                         down(dqio_mutex)
4753  *     down(dqio_mutex)                    jbd2_journal_start()
4754  *
4755  */
4756
4757 #ifdef CONFIG_QUOTA
4758
4759 static inline struct inode *dquot_to_inode(struct dquot *dquot)
4760 {
4761         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
4762 }
4763
4764 static int ext4_write_dquot(struct dquot *dquot)
4765 {
4766         int ret, err;
4767         handle_t *handle;
4768         struct inode *inode;
4769
4770         inode = dquot_to_inode(dquot);
4771         handle = ext4_journal_start(inode,
4772                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4773         if (IS_ERR(handle))
4774                 return PTR_ERR(handle);
4775         ret = dquot_commit(dquot);
4776         err = ext4_journal_stop(handle);
4777         if (!ret)
4778                 ret = err;
4779         return ret;
4780 }
4781
4782 static int ext4_acquire_dquot(struct dquot *dquot)
4783 {
4784         int ret, err;
4785         handle_t *handle;
4786
4787         handle = ext4_journal_start(dquot_to_inode(dquot),
4788                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4789         if (IS_ERR(handle))
4790                 return PTR_ERR(handle);
4791         ret = dquot_acquire(dquot);
4792         err = ext4_journal_stop(handle);
4793         if (!ret)
4794                 ret = err;
4795         return ret;
4796 }
4797
4798 static int ext4_release_dquot(struct dquot *dquot)
4799 {
4800         int ret, err;
4801         handle_t *handle;
4802
4803         handle = ext4_journal_start(dquot_to_inode(dquot),
4804                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4805         if (IS_ERR(handle)) {
4806                 /* Release dquot anyway to avoid endless cycle in dqput() */
4807                 dquot_release(dquot);
4808                 return PTR_ERR(handle);
4809         }
4810         ret = dquot_release(dquot);
4811         err = ext4_journal_stop(handle);
4812         if (!ret)
4813                 ret = err;
4814         return ret;
4815 }
4816
4817 static int ext4_mark_dquot_dirty(struct dquot *dquot)
4818 {
4819         /* Are we journaling quotas? */
4820         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
4821             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
4822                 dquot_mark_dquot_dirty(dquot);
4823                 return ext4_write_dquot(dquot);
4824         } else {
4825                 return dquot_mark_dquot_dirty(dquot);
4826         }
4827 }
4828
4829 static int ext4_write_info(struct super_block *sb, int type)
4830 {
4831         int ret, err;
4832         handle_t *handle;
4833
4834         /* Data block + inode block */
4835         handle = ext4_journal_start(sb->s_root->d_inode, 2);
4836         if (IS_ERR(handle))
4837                 return PTR_ERR(handle);
4838         ret = dquot_commit_info(sb, type);
4839         err = ext4_journal_stop(handle);
4840         if (!ret)
4841                 ret = err;
4842         return ret;
4843 }
4844
4845 /*
4846  * Turn on quotas during mount time - we need to find
4847  * the quota file and such...
4848  */
4849 static int ext4_quota_on_mount(struct super_block *sb, int type)
4850 {
4851         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4852                                         EXT4_SB(sb)->s_jquota_fmt, type);
4853 }
4854
4855 /*
4856  * Standard function to be called on quota_on
4857  */
4858 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4859                          struct path *path)
4860 {
4861         int err;
4862
4863         if (!test_opt(sb, QUOTA))
4864                 return -EINVAL;
4865
4866         /* Quotafile not on the same filesystem? */
4867         if (path->mnt->mnt_sb != sb)
4868                 return -EXDEV;
4869         /* Journaling quota? */
4870         if (EXT4_SB(sb)->s_qf_names[type]) {
4871                 /* Quotafile not in fs root? */
4872                 if (path->dentry->d_parent != sb->s_root)
4873                         ext4_msg(sb, KERN_WARNING,
4874                                 "Quota file not on filesystem root. "
4875                                 "Journaled quota will not work");
4876         }
4877
4878         /*
4879          * When we journal data on quota file, we have to flush journal to see
4880          * all updates to the file when we bypass pagecache...
4881          */
4882         if (EXT4_SB(sb)->s_journal &&
4883             ext4_should_journal_data(path->dentry->d_inode)) {
4884                 /*
4885                  * We don't need to lock updates but journal_flush() could
4886                  * otherwise be livelocked...
4887                  */
4888                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4889                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4890                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4891                 if (err)
4892                         return err;
4893         }
4894
4895         return dquot_quota_on(sb, type, format_id, path);
4896 }
4897
4898 static int ext4_quota_off(struct super_block *sb, int type)
4899 {
4900         struct inode *inode = sb_dqopt(sb)->files[type];
4901         handle_t *handle;
4902
4903         /* Force all delayed allocation blocks to be allocated.
4904          * Caller already holds s_umount sem */
4905         if (test_opt(sb, DELALLOC))
4906                 sync_filesystem(sb);
4907
4908         if (!inode)
4909                 goto out;
4910
4911         /* Update modification times of quota files when userspace can
4912          * start looking at them */
4913         handle = ext4_journal_start(inode, 1);
4914         if (IS_ERR(handle))
4915                 goto out;
4916         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
4917         ext4_mark_inode_dirty(handle, inode);
4918         ext4_journal_stop(handle);
4919
4920 out:
4921         return dquot_quota_off(sb, type);
4922 }
4923
4924 /* Read data from quotafile - avoid pagecache and such because we cannot afford
4925  * acquiring the locks... As quota files are never truncated and quota code
4926  * itself serializes the operations (and no one else should touch the files)
4927  * we don't have to be afraid of races */
4928 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
4929                                size_t len, loff_t off)
4930 {
4931         struct inode *inode = sb_dqopt(sb)->files[type];
4932         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4933         int err = 0;
4934         int offset = off & (sb->s_blocksize - 1);
4935         int tocopy;
4936         size_t toread;
4937         struct buffer_head *bh;
4938         loff_t i_size = i_size_read(inode);
4939
4940         if (off > i_size)
4941                 return 0;
4942         if (off+len > i_size)
4943                 len = i_size-off;
4944         toread = len;
4945         while (toread > 0) {
4946                 tocopy = sb->s_blocksize - offset < toread ?
4947                                 sb->s_blocksize - offset : toread;
4948                 bh = ext4_bread(NULL, inode, blk, 0, &err);
4949                 if (err)
4950                         return err;
4951                 if (!bh)        /* A hole? */
4952                         memset(data, 0, tocopy);
4953                 else
4954                         memcpy(data, bh->b_data+offset, tocopy);
4955                 brelse(bh);
4956                 offset = 0;
4957                 toread -= tocopy;
4958                 data += tocopy;
4959                 blk++;
4960         }
4961         return len;
4962 }
4963
4964 /* Write to quotafile (we know the transaction is already started and has
4965  * enough credits) */
4966 static ssize_t ext4_quota_write(struct super_block *sb, int type,
4967                                 const char *data, size_t len, loff_t off)
4968 {
4969         struct inode *inode = sb_dqopt(sb)->files[type];
4970         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4971         int err = 0;
4972         int offset = off & (sb->s_blocksize - 1);
4973         struct buffer_head *bh;
4974         handle_t *handle = journal_current_handle();
4975
4976         if (EXT4_SB(sb)->s_journal && !handle) {
4977                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4978                         " cancelled because transaction is not started",
4979                         (unsigned long long)off, (unsigned long long)len);
4980                 return -EIO;
4981         }
4982         /*
4983          * Since we account only one data block in transaction credits,
4984          * then it is impossible to cross a block boundary.
4985          */
4986         if (sb->s_blocksize - offset < len) {
4987                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4988                         " cancelled because not block aligned",
4989                         (unsigned long long)off, (unsigned long long)len);
4990                 return -EIO;
4991         }
4992
4993         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
4994         bh = ext4_bread(handle, inode, blk, 1, &err);
4995         if (!bh)
4996                 goto out;
4997         err = ext4_journal_get_write_access(handle, bh);
4998         if (err) {
4999                 brelse(bh);
5000                 goto out;
5001         }
5002         lock_buffer(bh);
5003         memcpy(bh->b_data+offset, data, len);
5004         flush_dcache_page(bh->b_page);
5005         unlock_buffer(bh);
5006         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5007         brelse(bh);
5008 out:
5009         if (err) {
5010                 mutex_unlock(&inode->i_mutex);
5011                 return err;
5012         }
5013         if (inode->i_size < off + len) {
5014                 i_size_write(inode, off + len);
5015                 EXT4_I(inode)->i_disksize = inode->i_size;
5016                 ext4_mark_inode_dirty(handle, inode);
5017         }
5018         mutex_unlock(&inode->i_mutex);
5019         return len;
5020 }
5021
5022 #endif
5023
5024 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5025                        const char *dev_name, void *data)
5026 {
5027         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5028 }
5029
5030 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5031 static inline void register_as_ext2(void)
5032 {
5033         int err = register_filesystem(&ext2_fs_type);
5034         if (err)
5035                 printk(KERN_WARNING
5036                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5037 }
5038
5039 static inline void unregister_as_ext2(void)
5040 {
5041         unregister_filesystem(&ext2_fs_type);
5042 }
5043
5044 static inline int ext2_feature_set_ok(struct super_block *sb)
5045 {
5046         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
5047                 return 0;
5048         if (sb->s_flags & MS_RDONLY)
5049                 return 1;
5050         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
5051                 return 0;
5052         return 1;
5053 }
5054 MODULE_ALIAS("ext2");
5055 #else
5056 static inline void register_as_ext2(void) { }
5057 static inline void unregister_as_ext2(void) { }
5058 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5059 #endif
5060
5061 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5062 static inline void register_as_ext3(void)
5063 {
5064         int err = register_filesystem(&ext3_fs_type);
5065         if (err)
5066                 printk(KERN_WARNING
5067                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5068 }
5069
5070 static inline void unregister_as_ext3(void)
5071 {
5072         unregister_filesystem(&ext3_fs_type);
5073 }
5074
5075 static inline int ext3_feature_set_ok(struct super_block *sb)
5076 {
5077         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
5078                 return 0;
5079         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
5080                 return 0;
5081         if (sb->s_flags & MS_RDONLY)
5082                 return 1;
5083         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
5084                 return 0;
5085         return 1;
5086 }
5087 MODULE_ALIAS("ext3");
5088 #else
5089 static inline void register_as_ext3(void) { }
5090 static inline void unregister_as_ext3(void) { }
5091 static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
5092 #endif
5093
5094 static struct file_system_type ext4_fs_type = {
5095         .owner          = THIS_MODULE,
5096         .name           = "ext4",
5097         .mount          = ext4_mount,
5098         .kill_sb        = kill_block_super,
5099         .fs_flags       = FS_REQUIRES_DEV,
5100 };
5101
5102 static int __init ext4_init_feat_adverts(void)
5103 {
5104         struct ext4_features *ef;
5105         int ret = -ENOMEM;
5106
5107         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
5108         if (!ef)
5109                 goto out;
5110
5111         ef->f_kobj.kset = ext4_kset;
5112         init_completion(&ef->f_kobj_unregister);
5113         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
5114                                    "features");
5115         if (ret) {
5116                 kfree(ef);
5117                 goto out;
5118         }
5119
5120         ext4_feat = ef;
5121         ret = 0;
5122 out:
5123         return ret;
5124 }
5125
5126 static void ext4_exit_feat_adverts(void)
5127 {
5128         kobject_put(&ext4_feat->f_kobj);
5129         wait_for_completion(&ext4_feat->f_kobj_unregister);
5130         kfree(ext4_feat);
5131 }
5132
5133 /* Shared across all ext4 file systems */
5134 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5135 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5136
5137 static int __init ext4_init_fs(void)
5138 {
5139         int i, err;
5140
5141         ext4_check_flag_values();
5142
5143         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5144                 mutex_init(&ext4__aio_mutex[i]);
5145                 init_waitqueue_head(&ext4__ioend_wq[i]);
5146         }
5147
5148         err = ext4_init_pageio();
5149         if (err)
5150                 return err;
5151         err = ext4_init_system_zone();
5152         if (err)
5153                 goto out6;
5154         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
5155         if (!ext4_kset)
5156                 goto out5;
5157         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
5158
5159         err = ext4_init_feat_adverts();
5160         if (err)
5161                 goto out4;
5162
5163         err = ext4_init_mballoc();
5164         if (err)
5165                 goto out3;
5166
5167         err = ext4_init_xattr();
5168         if (err)
5169                 goto out2;
5170         err = init_inodecache();
5171         if (err)
5172                 goto out1;
5173         register_as_ext3();
5174         register_as_ext2();
5175         err = register_filesystem(&ext4_fs_type);
5176         if (err)
5177                 goto out;
5178
5179         ext4_li_info = NULL;
5180         mutex_init(&ext4_li_mtx);
5181         return 0;
5182 out:
5183         unregister_as_ext2();
5184         unregister_as_ext3();
5185         destroy_inodecache();
5186 out1:
5187         ext4_exit_xattr();
5188 out2:
5189         ext4_exit_mballoc();
5190 out3:
5191         ext4_exit_feat_adverts();
5192 out4:
5193         if (ext4_proc_root)
5194                 remove_proc_entry("fs/ext4", NULL);
5195         kset_unregister(ext4_kset);
5196 out5:
5197         ext4_exit_system_zone();
5198 out6:
5199         ext4_exit_pageio();
5200         return err;
5201 }
5202
5203 static void __exit ext4_exit_fs(void)
5204 {
5205         ext4_destroy_lazyinit_thread();
5206         unregister_as_ext2();
5207         unregister_as_ext3();
5208         unregister_filesystem(&ext4_fs_type);
5209         destroy_inodecache();
5210         ext4_exit_xattr();
5211         ext4_exit_mballoc();
5212         ext4_exit_feat_adverts();
5213         remove_proc_entry("fs/ext4", NULL);
5214         kset_unregister(ext4_kset);
5215         ext4_exit_system_zone();
5216         ext4_exit_pageio();
5217 }
5218
5219 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5220 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5221 MODULE_LICENSE("GPL");
5222 module_init(ext4_init_fs)
5223 module_exit(ext4_exit_fs)