fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/jbd2.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/parser.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/cleancache.h>
  42 #include <asm/uaccess.h>
  43
  44 #include <linux/kthread.h>
  45 #include <linux/freezer.h>
  46
  47 #include "ext4.h"
  48 #include "ext4_extents.h"
  49 #include "ext4_jbd2.h"
  50 #include "xattr.h"
  51 #include "acl.h"
  52 #include "mballoc.h"
  53
  54 #define CREATE_TRACE_POINTS
  55 #include <trace/events/ext4.h>
  56
  57 static struct proc_dir_entry *ext4_proc_root;
  58 static struct kset *ext4_kset;
  59 static struct ext4_lazy_init *ext4_li_info;
  60 static struct mutex ext4_li_mtx;
  61 static struct ext4_features *ext4_feat;
  62
  63 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  64                              unsigned long journal_devnum);
  65 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  66 static int ext4_commit_super(struct super_block *sb, int sync);
  67 static void ext4_mark_recovery_complete(struct super_block *sb,
  68                                         struct ext4_super_block *es);
  69 static void ext4_clear_journal_err(struct super_block *sb,
  70                                    struct ext4_super_block *es);
  71 static int ext4_sync_fs(struct super_block *sb, int wait);
  72 static const char *ext4_decode_error(struct super_block *sb, int errno,
  73                                      char nbuf[16]);
  74 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  75 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  76 static int ext4_unfreeze(struct super_block *sb);
  77 static 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 static int ext4_verify_csum_type(struct super_block *sb,
 115                                  struct ext4_super_block *es)
 116 {
 117         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 118                                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 119                 return 1;
 120
 121         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 122 }
 123
 124 static __le32 ext4_superblock_csum(struct super_block *sb,
 125                                    struct ext4_super_block *es)
 126 {
 127         struct ext4_sb_info *sbi = EXT4_SB(sb);
 128         int offset = offsetof(struct ext4_super_block, s_checksum);
 129         __u32 csum;
 130
 131         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 132
 133         return cpu_to_le32(csum);
 134 }
 135
 136 int ext4_superblock_csum_verify(struct super_block *sb,
 137                                 struct ext4_super_block *es)
 138 {
 139         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 140                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 141                 return 1;
 142
 143         return es->s_checksum == ext4_superblock_csum(sb, es);
 144 }
 145
 146 void ext4_superblock_csum_set(struct super_block *sb,
 147                               struct ext4_super_block *es)
 148 {
 149         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 150                 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 151                 return;
 152
 153         es->s_checksum = ext4_superblock_csum(sb, es);
 154 }
 155
 156 void *ext4_kvmalloc(size_t size, gfp_t flags)
 157 {
 158         void *ret;
 159
 160         ret = kmalloc(size, flags);
 161         if (!ret)
 162                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 163         return ret;
 164 }
 165
 166 void *ext4_kvzalloc(size_t size, gfp_t flags)
 167 {
 168         void *ret;
 169
 170         ret = kzalloc(size, flags);
 171         if (!ret)
 172                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 173         return ret;
 174 }
 175
 176 void ext4_kvfree(void *ptr)
 177 {
 178         if (is_vmalloc_addr(ptr))
 179                 vfree(ptr);
 180         else
 181                 kfree(ptr);
 182
 183 }
 184
 185 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 186                                struct ext4_group_desc *bg)
 187 {
 188         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 189                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 190                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 191 }
 192
 193 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 194                                struct ext4_group_desc *bg)
 195 {
 196         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 197                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 198                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 199 }
 200
 201 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 202                               struct ext4_group_desc *bg)
 203 {
 204         return le32_to_cpu(bg->bg_inode_table_lo) |
 205                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 206                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 207 }
 208
 209 __u32 ext4_free_group_clusters(struct super_block *sb,
 210                                struct ext4_group_desc *bg)
 211 {
 212         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 213                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 214                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 215 }
 216
 217 __u32 ext4_free_inodes_count(struct super_block *sb,
 218                               struct ext4_group_desc *bg)
 219 {
 220         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 221                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 222                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 223 }
 224
 225 __u32 ext4_used_dirs_count(struct super_block *sb,
 226                               struct ext4_group_desc *bg)
 227 {
 228         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 229                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 230                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 231 }
 232
 233 __u32 ext4_itable_unused_count(struct super_block *sb,
 234                               struct ext4_group_desc *bg)
 235 {
 236         return le16_to_cpu(bg->bg_itable_unused_lo) |
 237                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 238                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 239 }
 240
 241 void ext4_block_bitmap_set(struct super_block *sb,
 242                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 243 {
 244         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 245         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 246                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 247 }
 248
 249 void ext4_inode_bitmap_set(struct super_block *sb,
 250                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 251 {
 252         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 253         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 254                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 255 }
 256
 257 void ext4_inode_table_set(struct super_block *sb,
 258                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 259 {
 260         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 261         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 262                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 263 }
 264
 265 void ext4_free_group_clusters_set(struct super_block *sb,
 266                                   struct ext4_group_desc *bg, __u32 count)
 267 {
 268         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 269         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 270                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 271 }
 272
 273 void ext4_free_inodes_set(struct super_block *sb,
 274                           struct ext4_group_desc *bg, __u32 count)
 275 {
 276         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 277         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 278                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 279 }
 280
 281 void ext4_used_dirs_set(struct super_block *sb,
 282                           struct ext4_group_desc *bg, __u32 count)
 283 {
 284         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 285         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 286                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 287 }
 288
 289 void ext4_itable_unused_set(struct super_block *sb,
 290                           struct ext4_group_desc *bg, __u32 count)
 291 {
 292         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 293         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 294                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 295 }
 296
 297
 298 /* Just increment the non-pointer handle value */
 299 static handle_t *ext4_get_nojournal(void)
 300 {
 301         handle_t *handle = current->journal_info;
 302         unsigned long ref_cnt = (unsigned long)handle;
 303
 304         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
 305
 306         ref_cnt++;
 307         handle = (handle_t *)ref_cnt;
 308
 309         current->journal_info = handle;
 310         return handle;
 311 }
 312
 313
 314 /* Decrement the non-pointer handle value */
 315 static void ext4_put_nojournal(handle_t *handle)
 316 {
 317         unsigned long ref_cnt = (unsigned long)handle;
 318
 319         BUG_ON(ref_cnt == 0);
 320
 321         ref_cnt--;
 322         handle = (handle_t *)ref_cnt;
 323
 324         current->journal_info = handle;
 325 }
 326
 327 /*
 328  * Wrappers for jbd2_journal_start/end.
 329  */
 330 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 331 {
 332         journal_t *journal;
 333
 334         trace_ext4_journal_start(sb, nblocks, _RET_IP_);
 335         if (sb->s_flags & MS_RDONLY)
 336                 return ERR_PTR(-EROFS);
 337
 338         WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);
 339         journal = EXT4_SB(sb)->s_journal;
 340         if (!journal)
 341                 return ext4_get_nojournal();
 342         /*
 343          * Special case here: if the journal has aborted behind our
 344          * backs (eg. EIO in the commit thread), then we still need to
 345          * take the FS itself readonly cleanly.
 346          */
 347         if (is_journal_aborted(journal)) {
 348                 ext4_abort(sb, "Detected aborted journal");
 349                 return ERR_PTR(-EROFS);
 350         }
 351         return jbd2_journal_start(journal, nblocks);
 352 }
 353
 354 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
 355 {
 356         struct super_block *sb;
 357         int err;
 358         int rc;
 359
 360         if (!ext4_handle_valid(handle)) {
 361                 ext4_put_nojournal(handle);
 362                 return 0;
 363         }
 364         sb = handle->h_transaction->t_journal->j_private;
 365         err = handle->h_err;
 366         rc = jbd2_journal_stop(handle);
 367
 368         if (!err)
 369                 err = rc;
 370         if (err)
 371                 __ext4_std_error(sb, where, line, err);
 372         return err;
 373 }
 374
 375 void ext4_journal_abort_handle(const char *caller, unsigned int line,
 376                                const char *err_fn, struct buffer_head *bh,
 377                                handle_t *handle, int err)
 378 {
 379         char nbuf[16];
 380         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 381
 382         BUG_ON(!ext4_handle_valid(handle));
 383
 384         if (bh)
 385                 BUFFER_TRACE(bh, "abort");
 386
 387         if (!handle->h_err)
 388                 handle->h_err = err;
 389
 390         if (is_handle_aborted(handle))
 391                 return;
 392
 393         printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n",
 394                caller, line, errstr, err_fn);
 395
 396         jbd2_journal_abort_handle(handle);
 397 }
 398
 399 static void __save_error_info(struct super_block *sb, const char *func,
 400                             unsigned int line)
 401 {
 402         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 403
 404         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 405         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 406         es->s_last_error_time = cpu_to_le32(get_seconds());
 407         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 408         es->s_last_error_line = cpu_to_le32(line);
 409         if (!es->s_first_error_time) {
 410                 es->s_first_error_time = es->s_last_error_time;
 411                 strncpy(es->s_first_error_func, func,
 412                         sizeof(es->s_first_error_func));
 413                 es->s_first_error_line = cpu_to_le32(line);
 414                 es->s_first_error_ino = es->s_last_error_ino;
 415                 es->s_first_error_block = es->s_last_error_block;
 416         }
 417         /*
 418          * Start the daily error reporting function if it hasn't been
 419          * started already
 420          */
 421         if (!es->s_error_count)
 422                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 423         es->s_error_count = cpu_to_le32(le32_to_cpu(es->s_error_count) + 1);
 424 }
 425
 426 static void save_error_info(struct super_block *sb, const char *func,
 427                             unsigned int line)
 428 {
 429         __save_error_info(sb, func, line);
 430         ext4_commit_super(sb, 1);
 431 }
 432
 433 /*
 434  * The del_gendisk() function uninitializes the disk-specific data
 435  * structures, including the bdi structure, without telling anyone
 436  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 437  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 438  * This is a kludge to prevent these oops until we can put in a proper
 439  * hook in del_gendisk() to inform the VFS and file system layers.
 440  */
 441 static int block_device_ejected(struct super_block *sb)
 442 {
 443         struct inode *bd_inode = sb->s_bdev->bd_inode;
 444         struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info;
 445
 446         return bdi->dev == NULL;
 447 }
 448
 449 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 450 {
 451         struct super_block              *sb = journal->j_private;
 452         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 453         int                             error = is_journal_aborted(journal);
 454         struct ext4_journal_cb_entry    *jce, *tmp;
 455
 456         spin_lock(&sbi->s_md_lock);
 457         list_for_each_entry_safe(jce, tmp, &txn->t_private_list, jce_list) {
 458                 list_del_init(&jce->jce_list);
 459                 spin_unlock(&sbi->s_md_lock);
 460                 jce->jce_func(sb, jce, error);
 461                 spin_lock(&sbi->s_md_lock);
 462         }
 463         spin_unlock(&sbi->s_md_lock);
 464 }
 465
 466 /* Deal with the reporting of failure conditions on a filesystem such as
 467  * inconsistencies detected or read IO failures.
 468  *
 469  * On ext2, we can store the error state of the filesystem in the
 470  * superblock.  That is not possible on ext4, because we may have other
 471  * write ordering constraints on the superblock which prevent us from
 472  * writing it out straight away; and given that the journal is about to
 473  * be aborted, we can't rely on the current, or future, transactions to
 474  * write out the superblock safely.
 475  *
 476  * We'll just use the jbd2_journal_abort() error code to record an error in
 477  * the journal instead.  On recovery, the journal will complain about
 478  * that error until we've noted it down and cleared it.
 479  */
 480
 481 static void ext4_handle_error(struct super_block *sb)
 482 {
 483         if (sb->s_flags & MS_RDONLY)
 484                 return;
 485
 486         if (!test_opt(sb, ERRORS_CONT)) {
 487                 journal_t *journal = EXT4_SB(sb)->s_journal;
 488
 489                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 490                 if (journal)
 491                         jbd2_journal_abort(journal, -EIO);
 492         }
 493         if (test_opt(sb, ERRORS_RO)) {
 494                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 495                 sb->s_flags |= MS_RDONLY;
 496         }
 497         if (test_opt(sb, ERRORS_PANIC))
 498                 panic("EXT4-fs (device %s): panic forced after error\n",
 499                         sb->s_id);
 500 }
 501
 502 void __ext4_error(struct super_block *sb, const char *function,
 503                   unsigned int line, const char *fmt, ...)
 504 {
 505         struct va_format vaf;
 506         va_list args;
 507
 508         va_start(args, fmt);
 509         vaf.fmt = fmt;
 510         vaf.va = &args;
 511         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 512                sb->s_id, function, line, current->comm, &vaf);
 513         va_end(args);
 514         save_error_info(sb, function, line);
 515
 516         ext4_handle_error(sb);
 517 }
 518
 519 void ext4_error_inode(struct inode *inode, const char *function,
 520                       unsigned int line, ext4_fsblk_t block,
 521                       const char *fmt, ...)
 522 {
 523         va_list args;
 524         struct va_format vaf;
 525         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 526
 527         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 528         es->s_last_error_block = cpu_to_le64(block);
 529         save_error_info(inode->i_sb, function, line);
 530         va_start(args, fmt);
 531         vaf.fmt = fmt;
 532         vaf.va = &args;
 533         if (block)
 534                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 535                        "inode #%lu: block %llu: comm %s: %pV\n",
 536                        inode->i_sb->s_id, function, line, inode->i_ino,
 537                        block, current->comm, &vaf);
 538         else
 539                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 540                        "inode #%lu: comm %s: %pV\n",
 541                        inode->i_sb->s_id, function, line, inode->i_ino,
 542                        current->comm, &vaf);
 543         va_end(args);
 544
 545         ext4_handle_error(inode->i_sb);
 546 }
 547
 548 void ext4_error_file(struct file *file, const char *function,
 549                      unsigned int line, ext4_fsblk_t block,
 550                      const char *fmt, ...)
 551 {
 552         va_list args;
 553         struct va_format vaf;
 554         struct ext4_super_block *es;
 555         struct inode *inode = file->f_dentry->d_inode;
 556         char pathname[80], *path;
 557
 558         es = EXT4_SB(inode->i_sb)->s_es;
 559         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 560         save_error_info(inode->i_sb, function, line);
 561         path = d_path(&(file->f_path), pathname, sizeof(pathname));
 562         if (IS_ERR(path))
 563                 path = "(unknown)";
 564         va_start(args, fmt);
 565         vaf.fmt = fmt;
 566         vaf.va = &args;
 567         if (block)
 568                 printk(KERN_CRIT
 569                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 570                        "block %llu: comm %s: path %s: %pV\n",
 571                        inode->i_sb->s_id, function, line, inode->i_ino,
 572                        block, current->comm, path, &vaf);
 573         else
 574                 printk(KERN_CRIT
 575                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 576                        "comm %s: path %s: %pV\n",
 577                        inode->i_sb->s_id, function, line, inode->i_ino,
 578                        current->comm, path, &vaf);
 579         va_end(args);
 580
 581         ext4_handle_error(inode->i_sb);
 582 }
 583
 584 static const char *ext4_decode_error(struct super_block *sb, int errno,
 585                                      char nbuf[16])
 586 {
 587         char *errstr = NULL;
 588
 589         switch (errno) {
 590         case -EIO:
 591                 errstr = "IO failure";
 592                 break;
 593         case -ENOMEM:
 594                 errstr = "Out of memory";
 595                 break;
 596         case -EROFS:
 597                 if (!sb || (EXT4_SB(sb)->s_journal &&
 598                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 599                         errstr = "Journal has aborted";
 600                 else
 601                         errstr = "Readonly filesystem";
 602                 break;
 603         default:
 604                 /* If the caller passed in an extra buffer for unknown
 605                  * errors, textualise them now.  Else we just return
 606                  * NULL. */
 607                 if (nbuf) {
 608                         /* Check for truncated error codes... */
 609                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 610                                 errstr = nbuf;
 611                 }
 612                 break;
 613         }
 614
 615         return errstr;
 616 }
 617
 618 /* __ext4_std_error decodes expected errors from journaling functions
 619  * automatically and invokes the appropriate error response.  */
 620
 621 void __ext4_std_error(struct super_block *sb, const char *function,
 622                       unsigned int line, int errno)
 623 {
 624         char nbuf[16];
 625         const char *errstr;
 626
 627         /* Special case: if the error is EROFS, and we're not already
 628          * inside a transaction, then there's really no point in logging
 629          * an error. */
 630         if (errno == -EROFS && journal_current_handle() == NULL &&
 631             (sb->s_flags & MS_RDONLY))
 632                 return;
 633
 634         errstr = ext4_decode_error(sb, errno, nbuf);
 635         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 636                sb->s_id, function, line, errstr);
 637         save_error_info(sb, function, line);
 638
 639         ext4_handle_error(sb);
 640 }
 641
 642 /*
 643  * ext4_abort is a much stronger failure handler than ext4_error.  The
 644  * abort function may be used to deal with unrecoverable failures such
 645  * as journal IO errors or ENOMEM at a critical moment in log management.
 646  *
 647  * We unconditionally force the filesystem into an ABORT|READONLY state,
 648  * unless the error response on the fs has been set to panic in which
 649  * case we take the easy way out and panic immediately.
 650  */
 651
 652 void __ext4_abort(struct super_block *sb, const char *function,
 653                 unsigned int line, const char *fmt, ...)
 654 {
 655         va_list args;
 656
 657         save_error_info(sb, function, line);
 658         va_start(args, fmt);
 659         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 660                function, line);
 661         vprintk(fmt, args);
 662         printk("\n");
 663         va_end(args);
 664
 665         if ((sb->s_flags & MS_RDONLY) == 0) {
 666                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 667                 sb->s_flags |= MS_RDONLY;
 668                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 669                 if (EXT4_SB(sb)->s_journal)
 670                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 671                 save_error_info(sb, function, line);
 672         }
 673         if (test_opt(sb, ERRORS_PANIC))
 674                 panic("EXT4-fs panic from previous error\n");
 675 }
 676
 677 void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
 678 {
 679         struct va_format vaf;
 680         va_list args;
 681
 682         va_start(args, fmt);
 683         vaf.fmt = fmt;
 684         vaf.va = &args;
 685         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 686         va_end(args);
 687 }
 688
 689 void __ext4_warning(struct super_block *sb, const char *function,
 690                     unsigned int line, const char *fmt, ...)
 691 {
 692         struct va_format vaf;
 693         va_list args;
 694
 695         va_start(args, fmt);
 696         vaf.fmt = fmt;
 697         vaf.va = &args;
 698         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 699                sb->s_id, function, line, &vaf);
 700         va_end(args);
 701 }
 702
 703 void __ext4_grp_locked_error(const char *function, unsigned int line,
 704                              struct super_block *sb, ext4_group_t grp,
 705                              unsigned long ino, ext4_fsblk_t block,
 706                              const char *fmt, ...)
 707 __releases(bitlock)
 708 __acquires(bitlock)
 709 {
 710         struct va_format vaf;
 711         va_list args;
 712         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 713
 714         es->s_last_error_ino = cpu_to_le32(ino);
 715         es->s_last_error_block = cpu_to_le64(block);
 716         __save_error_info(sb, function, line);
 717
 718         va_start(args, fmt);
 719
 720         vaf.fmt = fmt;
 721         vaf.va = &args;
 722         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 723                sb->s_id, function, line, grp);
 724         if (ino)
 725                 printk(KERN_CONT "inode %lu: ", ino);
 726         if (block)
 727                 printk(KERN_CONT "block %llu:", (unsigned long long) block);
 728         printk(KERN_CONT "%pV\n", &vaf);
 729         va_end(args);
 730
 731         if (test_opt(sb, ERRORS_CONT)) {
 732                 ext4_commit_super(sb, 0);
 733                 return;
 734         }
 735
 736         ext4_unlock_group(sb, grp);
 737         ext4_handle_error(sb);
 738         /*
 739          * We only get here in the ERRORS_RO case; relocking the group
 740          * may be dangerous, but nothing bad will happen since the
 741          * filesystem will have already been marked read/only and the
 742          * journal has been aborted.  We return 1 as a hint to callers
 743          * who might what to use the return value from
 744          * ext4_grp_locked_error() to distinguish between the
 745          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 746          * aggressively from the ext4 function in question, with a
 747          * more appropriate error code.
 748          */
 749         ext4_lock_group(sb, grp);
 750         return;
 751 }
 752
 753 void ext4_update_dynamic_rev(struct super_block *sb)
 754 {
 755         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 756
 757         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 758                 return;
 759
 760         ext4_warning(sb,
 761                      "updating to rev %d because of new feature flag, "
 762                      "running e2fsck is recommended",
 763                      EXT4_DYNAMIC_REV);
 764
 765         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 766         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 767         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 768         /* leave es->s_feature_*compat flags alone */
 769         /* es->s_uuid will be set by e2fsck if empty */
 770
 771         /*
 772          * The rest of the superblock fields should be zero, and if not it
 773          * means they are likely already in use, so leave them alone.  We
 774          * can leave it up to e2fsck to clean up any inconsistencies there.
 775          */
 776 }
 777
 778 /*
 779  * Open the external journal device
 780  */
 781 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 782 {
 783         struct block_device *bdev;
 784         char b[BDEVNAME_SIZE];
 785
 786         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 787         if (IS_ERR(bdev))
 788                 goto fail;
 789         return bdev;
 790
 791 fail:
 792         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 793                         __bdevname(dev, b), PTR_ERR(bdev));
 794         return NULL;
 795 }
 796
 797 /*
 798  * Release the journal device
 799  */
 800 static int ext4_blkdev_put(struct block_device *bdev)
 801 {
 802         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 803 }
 804
 805 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 806 {
 807         struct block_device *bdev;
 808         int ret = -ENODEV;
 809
 810         bdev = sbi->journal_bdev;
 811         if (bdev) {
 812                 ret = ext4_blkdev_put(bdev);
 813                 sbi->journal_bdev = NULL;
 814         }
 815         return ret;
 816 }
 817
 818 static inline struct inode *orphan_list_entry(struct list_head *l)
 819 {
 820         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 821 }
 822
 823 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 824 {
 825         struct list_head *l;
 826
 827         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 828                  le32_to_cpu(sbi->s_es->s_last_orphan));
 829
 830         printk(KERN_ERR "sb_info orphan list:\n");
 831         list_for_each(l, &sbi->s_orphan) {
 832                 struct inode *inode = orphan_list_entry(l);
 833                 printk(KERN_ERR "  "
 834                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 835                        inode->i_sb->s_id, inode->i_ino, inode,
 836                        inode->i_mode, inode->i_nlink,
 837                        NEXT_ORPHAN(inode));
 838         }
 839 }
 840
 841 static void ext4_put_super(struct super_block *sb)
 842 {
 843         struct ext4_sb_info *sbi = EXT4_SB(sb);
 844         struct ext4_super_block *es = sbi->s_es;
 845         int i, err;
 846
 847         ext4_unregister_li_request(sb);
 848         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 849
 850         flush_workqueue(sbi->dio_unwritten_wq);
 851         destroy_workqueue(sbi->dio_unwritten_wq);
 852
 853         lock_super(sb);
 854         if (sbi->s_journal) {
 855                 err = jbd2_journal_destroy(sbi->s_journal);
 856                 sbi->s_journal = NULL;
 857                 if (err < 0)
 858                         ext4_abort(sb, "Couldn't clean up the journal");
 859         }
 860
 861         del_timer(&sbi->s_err_report);
 862         ext4_release_system_zone(sb);
 863         ext4_mb_release(sb);
 864         ext4_ext_release(sb);
 865         ext4_xattr_put_super(sb);
 866
 867         if (!(sb->s_flags & MS_RDONLY)) {
 868                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 869                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 870         }
 871         if (!(sb->s_flags & MS_RDONLY))
 872                 ext4_commit_super(sb, 1);
 873
 874         if (sbi->s_proc) {
 875                 remove_proc_entry("options", sbi->s_proc);
 876                 remove_proc_entry(sb->s_id, ext4_proc_root);
 877         }
 878         kobject_del(&sbi->s_kobj);
 879
 880         for (i = 0; i < sbi->s_gdb_count; i++)
 881                 brelse(sbi->s_group_desc[i]);
 882         ext4_kvfree(sbi->s_group_desc);
 883         ext4_kvfree(sbi->s_flex_groups);
 884         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 885         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 886         percpu_counter_destroy(&sbi->s_dirs_counter);
 887         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 888         brelse(sbi->s_sbh);
 889 #ifdef CONFIG_QUOTA
 890         for (i = 0; i < MAXQUOTAS; i++)
 891                 kfree(sbi->s_qf_names[i]);
 892 #endif
 893
 894         /* Debugging code just in case the in-memory inode orphan list
 895          * isn't empty.  The on-disk one can be non-empty if we've
 896          * detected an error and taken the fs readonly, but the
 897          * in-memory list had better be clean by this point. */
 898         if (!list_empty(&sbi->s_orphan))
 899                 dump_orphan_list(sb, sbi);
 900         J_ASSERT(list_empty(&sbi->s_orphan));
 901
 902         invalidate_bdev(sb->s_bdev);
 903         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 904                 /*
 905                  * Invalidate the journal device's buffers.  We don't want them
 906                  * floating about in memory - the physical journal device may
 907                  * hotswapped, and it breaks the `ro-after' testing code.
 908                  */
 909                 sync_blockdev(sbi->journal_bdev);
 910                 invalidate_bdev(sbi->journal_bdev);
 911                 ext4_blkdev_remove(sbi);
 912         }
 913         if (sbi->s_mmp_tsk)
 914                 kthread_stop(sbi->s_mmp_tsk);
 915         sb->s_fs_info = NULL;
 916         /*
 917          * Now that we are completely done shutting down the
 918          * superblock, we need to actually destroy the kobject.
 919          */
 920         unlock_super(sb);
 921         kobject_put(&sbi->s_kobj);
 922         wait_for_completion(&sbi->s_kobj_unregister);
 923         if (sbi->s_chksum_driver)
 924                 crypto_free_shash(sbi->s_chksum_driver);
 925         kfree(sbi->s_blockgroup_lock);
 926         kfree(sbi);
 927 }
 928
 929 static struct kmem_cache *ext4_inode_cachep;
 930
 931 /*
 932  * Called inside transaction, so use GFP_NOFS
 933  */
 934 static struct inode *ext4_alloc_inode(struct super_block *sb)
 935 {
 936         struct ext4_inode_info *ei;
 937
 938         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 939         if (!ei)
 940                 return NULL;
 941
 942         ei->vfs_inode.i_version = 1;
 943         ei->vfs_inode.i_data.writeback_index = 0;
 944         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 945         INIT_LIST_HEAD(&ei->i_prealloc_list);
 946         spin_lock_init(&ei->i_prealloc_lock);
 947         ei->i_reserved_data_blocks = 0;
 948         ei->i_reserved_meta_blocks = 0;
 949         ei->i_allocated_meta_blocks = 0;
 950         ei->i_da_metadata_calc_len = 0;
 951         ei->i_da_metadata_calc_last_lblock = 0;
 952         spin_lock_init(&(ei->i_block_reservation_lock));
 953 #ifdef CONFIG_QUOTA
 954         ei->i_reserved_quota = 0;
 955 #endif
 956         ei->jinode = NULL;
 957         INIT_LIST_HEAD(&ei->i_completed_io_list);
 958         spin_lock_init(&ei->i_completed_io_lock);
 959         ei->cur_aio_dio = NULL;
 960         ei->i_sync_tid = 0;
 961         ei->i_datasync_tid = 0;
 962         atomic_set(&ei->i_ioend_count, 0);
 963         atomic_set(&ei->i_aiodio_unwritten, 0);
 964
 965         return &ei->vfs_inode;
 966 }
 967
 968 static int ext4_drop_inode(struct inode *inode)
 969 {
 970         int drop = generic_drop_inode(inode);
 971
 972         trace_ext4_drop_inode(inode, drop);
 973         return drop;
 974 }
 975
 976 static void ext4_i_callback(struct rcu_head *head)
 977 {
 978         struct inode *inode = container_of(head, struct inode, i_rcu);
 979         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 980 }
 981
 982 static void ext4_destroy_inode(struct inode *inode)
 983 {
 984         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 985                 ext4_msg(inode->i_sb, KERN_ERR,
 986                          "Inode %lu (%p): orphan list check failed!",
 987                          inode->i_ino, EXT4_I(inode));
 988                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 989                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 990                                 true);
 991                 dump_stack();
 992         }
 993         call_rcu(&inode->i_rcu, ext4_i_callback);
 994 }
 995
 996 static void init_once(void *foo)
 997 {
 998         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 999
1000         INIT_LIST_HEAD(&ei->i_orphan);
1001 #ifdef CONFIG_EXT4_FS_XATTR
1002         init_rwsem(&ei->xattr_sem);
1003 #endif
1004         init_rwsem(&ei->i_data_sem);
1005         inode_init_once(&ei->vfs_inode);
1006 }
1007
1008 static int init_inodecache(void)
1009 {
1010         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
1011                                              sizeof(struct ext4_inode_info),
1012                                              0, (SLAB_RECLAIM_ACCOUNT|
1013                                                 SLAB_MEM_SPREAD),
1014                                              init_once);
1015         if (ext4_inode_cachep == NULL)
1016                 return -ENOMEM;
1017         return 0;
1018 }
1019
1020 static void destroy_inodecache(void)
1021 {
1022         kmem_cache_destroy(ext4_inode_cachep);
1023 }
1024
1025 void ext4_clear_inode(struct inode *inode)
1026 {
1027         invalidate_inode_buffers(inode);
1028         clear_inode(inode);
1029         dquot_drop(inode);
1030         ext4_discard_preallocations(inode);
1031         if (EXT4_I(inode)->jinode) {
1032                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1033                                                EXT4_I(inode)->jinode);
1034                 jbd2_free_inode(EXT4_I(inode)->jinode);
1035                 EXT4_I(inode)->jinode = NULL;
1036         }
1037 }
1038
1039 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1040                                         u64 ino, u32 generation)
1041 {
1042         struct inode *inode;
1043
1044         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1045                 return ERR_PTR(-ESTALE);
1046         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1047                 return ERR_PTR(-ESTALE);
1048
1049         /* iget isn't really right if the inode is currently unallocated!!
1050          *
1051          * ext4_read_inode will return a bad_inode if the inode had been
1052          * deleted, so we should be safe.
1053          *
1054          * Currently we don't know the generation for parent directory, so
1055          * a generation of 0 means "accept any"
1056          */
1057         inode = ext4_iget(sb, ino);
1058         if (IS_ERR(inode))
1059                 return ERR_CAST(inode);
1060         if (generation && inode->i_generation != generation) {
1061                 iput(inode);
1062                 return ERR_PTR(-ESTALE);
1063         }
1064
1065         return inode;
1066 }
1067
1068 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1069                                         int fh_len, int fh_type)
1070 {
1071         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1072                                     ext4_nfs_get_inode);
1073 }
1074
1075 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1076                                         int fh_len, int fh_type)
1077 {
1078         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1079                                     ext4_nfs_get_inode);
1080 }
1081
1082 /*
1083  * Try to release metadata pages (indirect blocks, directories) which are
1084  * mapped via the block device.  Since these pages could have journal heads
1085  * which would prevent try_to_free_buffers() from freeing them, we must use
1086  * jbd2 layer's try_to_free_buffers() function to release them.
1087  */
1088 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1089                                  gfp_t wait)
1090 {
1091         journal_t *journal = EXT4_SB(sb)->s_journal;
1092
1093         WARN_ON(PageChecked(page));
1094         if (!page_has_buffers(page))
1095                 return 0;
1096         if (journal)
1097                 return jbd2_journal_try_to_free_buffers(journal, page,
1098                                                         wait & ~__GFP_WAIT);
1099         return try_to_free_buffers(page);
1100 }
1101
1102 #ifdef CONFIG_QUOTA
1103 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1104 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1105
1106 static int ext4_write_dquot(struct dquot *dquot);
1107 static int ext4_acquire_dquot(struct dquot *dquot);
1108 static int ext4_release_dquot(struct dquot *dquot);
1109 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1110 static int ext4_write_info(struct super_block *sb, int type);
1111 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1112                          struct path *path);
1113 static int ext4_quota_on_sysfile(struct super_block *sb, int type,
1114                                  int format_id);
1115 static int ext4_quota_off(struct super_block *sb, int type);
1116 static int ext4_quota_off_sysfile(struct super_block *sb, int type);
1117 static int ext4_quota_on_mount(struct super_block *sb, int type);
1118 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1119                                size_t len, loff_t off);
1120 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1121                                 const char *data, size_t len, loff_t off);
1122 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1123                              unsigned int flags);
1124 static int ext4_enable_quotas(struct super_block *sb);
1125
1126 static const struct dquot_operations ext4_quota_operations = {
1127         .get_reserved_space = ext4_get_reserved_space,
1128         .write_dquot    = ext4_write_dquot,
1129         .acquire_dquot  = ext4_acquire_dquot,
1130         .release_dquot  = ext4_release_dquot,
1131         .mark_dirty     = ext4_mark_dquot_dirty,
1132         .write_info     = ext4_write_info,
1133         .alloc_dquot    = dquot_alloc,
1134         .destroy_dquot  = dquot_destroy,
1135 };
1136
1137 static const struct quotactl_ops ext4_qctl_operations = {
1138         .quota_on       = ext4_quota_on,
1139         .quota_off      = ext4_quota_off,
1140         .quota_sync     = dquot_quota_sync,
1141         .get_info       = dquot_get_dqinfo,
1142         .set_info       = dquot_set_dqinfo,
1143         .get_dqblk      = dquot_get_dqblk,
1144         .set_dqblk      = dquot_set_dqblk
1145 };
1146
1147 static const struct quotactl_ops ext4_qctl_sysfile_operations = {
1148         .quota_on_meta  = ext4_quota_on_sysfile,
1149         .quota_off      = ext4_quota_off_sysfile,
1150         .quota_sync     = dquot_quota_sync,
1151         .get_info       = dquot_get_dqinfo,
1152         .set_info       = dquot_set_dqinfo,
1153         .get_dqblk      = dquot_get_dqblk,
1154         .set_dqblk      = dquot_set_dqblk
1155 };
1156 #endif
1157
1158 static const struct super_operations ext4_sops = {
1159         .alloc_inode    = ext4_alloc_inode,
1160         .destroy_inode  = ext4_destroy_inode,
1161         .write_inode    = ext4_write_inode,
1162         .dirty_inode    = ext4_dirty_inode,
1163         .drop_inode     = ext4_drop_inode,
1164         .evict_inode    = ext4_evict_inode,
1165         .put_super      = ext4_put_super,
1166         .sync_fs        = ext4_sync_fs,
1167         .freeze_fs      = ext4_freeze,
1168         .unfreeze_fs    = ext4_unfreeze,
1169         .statfs         = ext4_statfs,
1170         .remount_fs     = ext4_remount,
1171         .show_options   = ext4_show_options,
1172 #ifdef CONFIG_QUOTA
1173         .quota_read     = ext4_quota_read,
1174         .quota_write    = ext4_quota_write,
1175 #endif
1176         .bdev_try_to_free_page = bdev_try_to_free_page,
1177 };
1178
1179 static const struct super_operations ext4_nojournal_sops = {
1180         .alloc_inode    = ext4_alloc_inode,
1181         .destroy_inode  = ext4_destroy_inode,
1182         .write_inode    = ext4_write_inode,
1183         .dirty_inode    = ext4_dirty_inode,
1184         .drop_inode     = ext4_drop_inode,
1185         .evict_inode    = ext4_evict_inode,
1186         .put_super      = ext4_put_super,
1187         .statfs         = ext4_statfs,
1188         .remount_fs     = ext4_remount,
1189         .show_options   = ext4_show_options,
1190 #ifdef CONFIG_QUOTA
1191         .quota_read     = ext4_quota_read,
1192         .quota_write    = ext4_quota_write,
1193 #endif
1194         .bdev_try_to_free_page = bdev_try_to_free_page,
1195 };
1196
1197 static const struct export_operations ext4_export_ops = {
1198         .fh_to_dentry = ext4_fh_to_dentry,
1199         .fh_to_parent = ext4_fh_to_parent,
1200         .get_parent = ext4_get_parent,
1201 };
1202
1203 enum {
1204         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1205         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1206         Opt_nouid32, Opt_debug, Opt_removed,
1207         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1208         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1209         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1210         Opt_journal_dev, Opt_journal_checksum, Opt_journal_async_commit,
1211         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1212         Opt_data_err_abort, Opt_data_err_ignore,
1213         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1214         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1215         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1216         Opt_usrquota, Opt_grpquota, Opt_i_version,
1217         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1218         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1219         Opt_inode_readahead_blks, Opt_journal_ioprio,
1220         Opt_dioread_nolock, Opt_dioread_lock,
1221         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1222 };
1223
1224 static const match_table_t tokens = {
1225         {Opt_bsd_df, "bsddf"},
1226         {Opt_minix_df, "minixdf"},
1227         {Opt_grpid, "grpid"},
1228         {Opt_grpid, "bsdgroups"},
1229         {Opt_nogrpid, "nogrpid"},
1230         {Opt_nogrpid, "sysvgroups"},
1231         {Opt_resgid, "resgid=%u"},
1232         {Opt_resuid, "resuid=%u"},
1233         {Opt_sb, "sb=%u"},
1234         {Opt_err_cont, "errors=continue"},
1235         {Opt_err_panic, "errors=panic"},
1236         {Opt_err_ro, "errors=remount-ro"},
1237         {Opt_nouid32, "nouid32"},
1238         {Opt_debug, "debug"},
1239         {Opt_removed, "oldalloc"},
1240         {Opt_removed, "orlov"},
1241         {Opt_user_xattr, "user_xattr"},
1242         {Opt_nouser_xattr, "nouser_xattr"},
1243         {Opt_acl, "acl"},
1244         {Opt_noacl, "noacl"},
1245         {Opt_noload, "norecovery"},
1246         {Opt_noload, "noload"},
1247         {Opt_removed, "nobh"},
1248         {Opt_removed, "bh"},
1249         {Opt_commit, "commit=%u"},
1250         {Opt_min_batch_time, "min_batch_time=%u"},
1251         {Opt_max_batch_time, "max_batch_time=%u"},
1252         {Opt_journal_dev, "journal_dev=%u"},
1253         {Opt_journal_checksum, "journal_checksum"},
1254         {Opt_journal_async_commit, "journal_async_commit"},
1255         {Opt_abort, "abort"},
1256         {Opt_data_journal, "data=journal"},
1257         {Opt_data_ordered, "data=ordered"},
1258         {Opt_data_writeback, "data=writeback"},
1259         {Opt_data_err_abort, "data_err=abort"},
1260         {Opt_data_err_ignore, "data_err=ignore"},
1261         {Opt_offusrjquota, "usrjquota="},
1262         {Opt_usrjquota, "usrjquota=%s"},
1263         {Opt_offgrpjquota, "grpjquota="},
1264         {Opt_grpjquota, "grpjquota=%s"},
1265         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1266         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1267         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1268         {Opt_grpquota, "grpquota"},
1269         {Opt_noquota, "noquota"},
1270         {Opt_quota, "quota"},
1271         {Opt_usrquota, "usrquota"},
1272         {Opt_barrier, "barrier=%u"},
1273         {Opt_barrier, "barrier"},
1274         {Opt_nobarrier, "nobarrier"},
1275         {Opt_i_version, "i_version"},
1276         {Opt_stripe, "stripe=%u"},
1277         {Opt_delalloc, "delalloc"},
1278         {Opt_nodelalloc, "nodelalloc"},
1279         {Opt_mblk_io_submit, "mblk_io_submit"},
1280         {Opt_nomblk_io_submit, "nomblk_io_submit"},
1281         {Opt_block_validity, "block_validity"},
1282         {Opt_noblock_validity, "noblock_validity"},
1283         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1284         {Opt_journal_ioprio, "journal_ioprio=%u"},
1285         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1286         {Opt_auto_da_alloc, "auto_da_alloc"},
1287         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1288         {Opt_dioread_nolock, "dioread_nolock"},
1289         {Opt_dioread_lock, "dioread_lock"},
1290         {Opt_discard, "discard"},
1291         {Opt_nodiscard, "nodiscard"},
1292         {Opt_init_itable, "init_itable=%u"},
1293         {Opt_init_itable, "init_itable"},
1294         {Opt_noinit_itable, "noinit_itable"},
1295         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1296         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1297         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1298         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1299         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1300         {Opt_err, NULL},
1301 };
1302
1303 static ext4_fsblk_t get_sb_block(void **data)
1304 {
1305         ext4_fsblk_t    sb_block;
1306         char            *options = (char *) *data;
1307
1308         if (!options || strncmp(options, "sb=", 3) != 0)
1309                 return 1;       /* Default location */
1310
1311         options += 3;
1312         /* TODO: use simple_strtoll with >32bit ext4 */
1313         sb_block = simple_strtoul(options, &options, 0);
1314         if (*options && *options != ',') {
1315                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1316                        (char *) *data);
1317                 return 1;
1318         }
1319         if (*options == ',')
1320                 options++;
1321         *data = (void *) options;
1322
1323         return sb_block;
1324 }
1325
1326 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1327 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1328         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1329
1330 #ifdef CONFIG_QUOTA
1331 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1332 {
1333         struct ext4_sb_info *sbi = EXT4_SB(sb);
1334         char *qname;
1335
1336         if (sb_any_quota_loaded(sb) &&
1337                 !sbi->s_qf_names[qtype]) {
1338                 ext4_msg(sb, KERN_ERR,
1339                         "Cannot change journaled "
1340                         "quota options when quota turned on");
1341                 return -1;
1342         }
1343         qname = match_strdup(args);
1344         if (!qname) {
1345                 ext4_msg(sb, KERN_ERR,
1346                         "Not enough memory for storing quotafile name");
1347                 return -1;
1348         }
1349         if (sbi->s_qf_names[qtype] &&
1350                 strcmp(sbi->s_qf_names[qtype], qname)) {
1351                 ext4_msg(sb, KERN_ERR,
1352                         "%s quota file already specified", QTYPE2NAME(qtype));
1353                 kfree(qname);
1354                 return -1;
1355         }
1356         sbi->s_qf_names[qtype] = qname;
1357         if (strchr(sbi->s_qf_names[qtype], '/')) {
1358                 ext4_msg(sb, KERN_ERR,
1359                         "quotafile must be on filesystem root");
1360                 kfree(sbi->s_qf_names[qtype]);
1361                 sbi->s_qf_names[qtype] = NULL;
1362                 return -1;
1363         }
1364         set_opt(sb, QUOTA);
1365         return 1;
1366 }
1367
1368 static int clear_qf_name(struct super_block *sb, int qtype)
1369 {
1370
1371         struct ext4_sb_info *sbi = EXT4_SB(sb);
1372
1373         if (sb_any_quota_loaded(sb) &&
1374                 sbi->s_qf_names[qtype]) {
1375                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1376                         " when quota turned on");
1377                 return -1;
1378         }
1379         /*
1380          * The space will be released later when all options are confirmed
1381          * to be correct
1382          */
1383         sbi->s_qf_names[qtype] = NULL;
1384         return 1;
1385 }
1386 #endif
1387
1388 #define MOPT_SET        0x0001
1389 #define MOPT_CLEAR      0x0002
1390 #define MOPT_NOSUPPORT  0x0004
1391 #define MOPT_EXPLICIT   0x0008
1392 #define MOPT_CLEAR_ERR  0x0010
1393 #define MOPT_GTE0       0x0020
1394 #ifdef CONFIG_QUOTA
1395 #define MOPT_Q          0
1396 #define MOPT_QFMT       0x0040
1397 #else
1398 #define MOPT_Q          MOPT_NOSUPPORT
1399 #define MOPT_QFMT       MOPT_NOSUPPORT
1400 #endif
1401 #define MOPT_DATAJ      0x0080
1402
1403 static const struct mount_opts {
1404         int     token;
1405         int     mount_opt;
1406         int     flags;
1407 } ext4_mount_opts[] = {
1408         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1409         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1410         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1411         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1412         {Opt_mblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_SET},
1413         {Opt_nomblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_CLEAR},
1414         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1415         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1416         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_SET},
1417         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_CLEAR},
1418         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1419         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1420         {Opt_delalloc, EXT4_MOUNT_DELALLOC, MOPT_SET | MOPT_EXPLICIT},
1421         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC, MOPT_CLEAR | MOPT_EXPLICIT},
1422         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM, MOPT_SET},
1423         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1424                                     EXT4_MOUNT_JOURNAL_CHECKSUM), MOPT_SET},
1425         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_SET},
1426         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1427         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1428         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1429         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_SET},
1430         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_CLEAR},
1431         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1432         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1433         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1434         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1435         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1436         {Opt_commit, 0, MOPT_GTE0},
1437         {Opt_max_batch_time, 0, MOPT_GTE0},
1438         {Opt_min_batch_time, 0, MOPT_GTE0},
1439         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1440         {Opt_init_itable, 0, MOPT_GTE0},
1441         {Opt_stripe, 0, MOPT_GTE0},
1442         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_DATAJ},
1443         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_DATAJ},
1444         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA, MOPT_DATAJ},
1445 #ifdef CONFIG_EXT4_FS_XATTR
1446         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1447         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1448 #else
1449         {Opt_user_xattr, 0, MOPT_NOSUPPORT},
1450         {Opt_nouser_xattr, 0, MOPT_NOSUPPORT},
1451 #endif
1452 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1453         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1454         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1455 #else
1456         {Opt_acl, 0, MOPT_NOSUPPORT},
1457         {Opt_noacl, 0, MOPT_NOSUPPORT},
1458 #endif
1459         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1460         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1461         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1462         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1463                                                         MOPT_SET | MOPT_Q},
1464         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1465                                                         MOPT_SET | MOPT_Q},
1466         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1467                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1468         {Opt_usrjquota, 0, MOPT_Q},
1469         {Opt_grpjquota, 0, MOPT_Q},
1470         {Opt_offusrjquota, 0, MOPT_Q},
1471         {Opt_offgrpjquota, 0, MOPT_Q},
1472         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1473         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1474         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1475         {Opt_err, 0, 0}
1476 };
1477
1478 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1479                             substring_t *args, unsigned long *journal_devnum,
1480                             unsigned int *journal_ioprio, int is_remount)
1481 {
1482         struct ext4_sb_info *sbi = EXT4_SB(sb);
1483         const struct mount_opts *m;
1484         kuid_t uid;
1485         kgid_t gid;
1486         int arg = 0;
1487
1488 #ifdef CONFIG_QUOTA
1489         if (token == Opt_usrjquota)
1490                 return set_qf_name(sb, USRQUOTA, &args[0]);
1491         else if (token == Opt_grpjquota)
1492                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1493         else if (token == Opt_offusrjquota)
1494                 return clear_qf_name(sb, USRQUOTA);
1495         else if (token == Opt_offgrpjquota)
1496                 return clear_qf_name(sb, GRPQUOTA);
1497 #endif
1498         if (args->from && match_int(args, &arg))
1499                 return -1;
1500         switch (token) {
1501         case Opt_noacl:
1502         case Opt_nouser_xattr:
1503                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1504                 break;
1505         case Opt_sb:
1506                 return 1;       /* handled by get_sb_block() */
1507         case Opt_removed:
1508                 ext4_msg(sb, KERN_WARNING,
1509                          "Ignoring removed %s option", opt);
1510                 return 1;
1511         case Opt_resuid:
1512                 uid = make_kuid(current_user_ns(), arg);
1513                 if (!uid_valid(uid)) {
1514                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1515                         return -1;
1516                 }
1517                 sbi->s_resuid = uid;
1518                 return 1;
1519         case Opt_resgid:
1520                 gid = make_kgid(current_user_ns(), arg);
1521                 if (!gid_valid(gid)) {
1522                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1523                         return -1;
1524                 }
1525                 sbi->s_resgid = gid;
1526                 return 1;
1527         case Opt_abort:
1528                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1529                 return 1;
1530         case Opt_i_version:
1531                 sb->s_flags |= MS_I_VERSION;
1532                 return 1;
1533         case Opt_journal_dev:
1534                 if (is_remount) {
1535                         ext4_msg(sb, KERN_ERR,
1536                                  "Cannot specify journal on remount");
1537                         return -1;
1538                 }
1539                 *journal_devnum = arg;
1540                 return 1;
1541         case Opt_journal_ioprio:
1542                 if (arg < 0 || arg > 7)
1543                         return -1;
1544                 *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1545                 return 1;
1546         }
1547
1548         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1549                 if (token != m->token)
1550                         continue;
1551                 if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1552                         return -1;
1553                 if (m->flags & MOPT_EXPLICIT)
1554                         set_opt2(sb, EXPLICIT_DELALLOC);
1555                 if (m->flags & MOPT_CLEAR_ERR)
1556                         clear_opt(sb, ERRORS_MASK);
1557                 if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1558                         ext4_msg(sb, KERN_ERR, "Cannot change quota "
1559                                  "options when quota turned on");
1560                         return -1;
1561                 }
1562
1563                 if (m->flags & MOPT_NOSUPPORT) {
1564                         ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1565                 } else if (token == Opt_commit) {
1566                         if (arg == 0)
1567                                 arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1568                         sbi->s_commit_interval = HZ * arg;
1569                 } else if (token == Opt_max_batch_time) {
1570                         if (arg == 0)
1571                                 arg = EXT4_DEF_MAX_BATCH_TIME;
1572                         sbi->s_max_batch_time = arg;
1573                 } else if (token == Opt_min_batch_time) {
1574                         sbi->s_min_batch_time = arg;
1575                 } else if (token == Opt_inode_readahead_blks) {
1576                         if (arg > (1 << 30))
1577                                 return -1;
1578                         if (arg && !is_power_of_2(arg)) {
1579                                 ext4_msg(sb, KERN_ERR,
1580                                          "EXT4-fs: inode_readahead_blks"
1581                                          " must be a power of 2");
1582                                 return -1;
1583                         }
1584                         sbi->s_inode_readahead_blks = arg;
1585                 } else if (token == Opt_init_itable) {
1586                         set_opt(sb, INIT_INODE_TABLE);
1587                         if (!args->from)
1588                                 arg = EXT4_DEF_LI_WAIT_MULT;
1589                         sbi->s_li_wait_mult = arg;
1590                 } else if (token == Opt_stripe) {
1591                         sbi->s_stripe = arg;
1592                 } else if (m->flags & MOPT_DATAJ) {
1593                         if (is_remount) {
1594                                 if (!sbi->s_journal)
1595                                         ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1596                                 else if (test_opt(sb, DATA_FLAGS) !=
1597                                          m->mount_opt) {
1598                                         ext4_msg(sb, KERN_ERR,
1599                                          "Cannot change data mode on remount");
1600                                         return -1;
1601                                 }
1602                         } else {
1603                                 clear_opt(sb, DATA_FLAGS);
1604                                 sbi->s_mount_opt |= m->mount_opt;
1605                         }
1606 #ifdef CONFIG_QUOTA
1607                 } else if (m->flags & MOPT_QFMT) {
1608                         if (sb_any_quota_loaded(sb) &&
1609                             sbi->s_jquota_fmt != m->mount_opt) {
1610                                 ext4_msg(sb, KERN_ERR, "Cannot "
1611                                          "change journaled quota options "
1612                                          "when quota turned on");
1613                                 return -1;
1614                         }
1615                         sbi->s_jquota_fmt = m->mount_opt;
1616 #endif
1617                 } else {
1618                         if (!args->from)
1619                                 arg = 1;
1620                         if (m->flags & MOPT_CLEAR)
1621                                 arg = !arg;
1622                         else if (unlikely(!(m->flags & MOPT_SET))) {
1623                                 ext4_msg(sb, KERN_WARNING,
1624                                          "buggy handling of option %s", opt);
1625                                 WARN_ON(1);
1626                                 return -1;
1627                         }
1628                         if (arg != 0)
1629                                 sbi->s_mount_opt |= m->mount_opt;
1630                         else
1631                                 sbi->s_mount_opt &= ~m->mount_opt;
1632                 }
1633                 return 1;
1634         }
1635         ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1636                  "or missing value", opt);
1637         return -1;
1638 }
1639
1640 static int parse_options(char *options, struct super_block *sb,
1641                          unsigned long *journal_devnum,
1642                          unsigned int *journal_ioprio,
1643                          int is_remount)
1644 {
1645 #ifdef CONFIG_QUOTA
1646         struct ext4_sb_info *sbi = EXT4_SB(sb);
1647 #endif
1648         char *p;
1649         substring_t args[MAX_OPT_ARGS];
1650         int token;
1651
1652         if (!options)
1653                 return 1;
1654
1655         while ((p = strsep(&options, ",")) != NULL) {
1656                 if (!*p)
1657                         continue;
1658                 /*
1659                  * Initialize args struct so we know whether arg was
1660                  * found; some options take optional arguments.
1661                  */
1662                 args[0].to = args[0].from = 0;
1663                 token = match_token(p, tokens, args);
1664                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1665                                      journal_ioprio, is_remount) < 0)
1666                         return 0;
1667         }
1668 #ifdef CONFIG_QUOTA
1669         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1670                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1671                         clear_opt(sb, USRQUOTA);
1672
1673                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1674                         clear_opt(sb, GRPQUOTA);
1675
1676                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1677                         ext4_msg(sb, KERN_ERR, "old and new quota "
1678                                         "format mixing");
1679                         return 0;
1680                 }
1681
1682                 if (!sbi->s_jquota_fmt) {
1683                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1684                                         "not specified");
1685                         return 0;
1686                 }
1687         } else {
1688                 if (sbi->s_jquota_fmt) {
1689                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1690                                         "specified with no journaling "
1691                                         "enabled");
1692                         return 0;
1693                 }
1694         }
1695 #endif
1696         return 1;
1697 }
1698
1699 static inline void ext4_show_quota_options(struct seq_file *seq,
1700                                            struct super_block *sb)
1701 {
1702 #if defined(CONFIG_QUOTA)
1703         struct ext4_sb_info *sbi = EXT4_SB(sb);
1704
1705         if (sbi->s_jquota_fmt) {
1706                 char *fmtname = "";
1707
1708                 switch (sbi->s_jquota_fmt) {
1709                 case QFMT_VFS_OLD:
1710                         fmtname = "vfsold";
1711                         break;
1712                 case QFMT_VFS_V0:
1713                         fmtname = "vfsv0";
1714                         break;
1715                 case QFMT_VFS_V1:
1716                         fmtname = "vfsv1";
1717                         break;
1718                 }
1719                 seq_printf(seq, ",jqfmt=%s", fmtname);
1720         }
1721
1722         if (sbi->s_qf_names[USRQUOTA])
1723                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1724
1725         if (sbi->s_qf_names[GRPQUOTA])
1726                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1727
1728         if (test_opt(sb, USRQUOTA))
1729                 seq_puts(seq, ",usrquota");
1730
1731         if (test_opt(sb, GRPQUOTA))
1732                 seq_puts(seq, ",grpquota");
1733 #endif
1734 }
1735
1736 static const char *token2str(int token)
1737 {
1738         const struct match_token *t;
1739
1740         for (t = tokens; t->token != Opt_err; t++)
1741                 if (t->token == token && !strchr(t->pattern, '='))
1742                         break;
1743         return t->pattern;
1744 }
1745
1746 /*
1747  * Show an option if
1748  *  - it's set to a non-default value OR
1749  *  - if the per-sb default is different from the global default
1750  */
1751 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1752                               int nodefs)
1753 {
1754         struct ext4_sb_info *sbi = EXT4_SB(sb);
1755         struct ext4_super_block *es = sbi->s_es;
1756         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1757         const struct mount_opts *m;
1758         char sep = nodefs ? '\n' : ',';
1759
1760 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1761 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1762
1763         if (sbi->s_sb_block != 1)
1764                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1765
1766         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1767                 int want_set = m->flags & MOPT_SET;
1768                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1769                     (m->flags & MOPT_CLEAR_ERR))
1770                         continue;
1771                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1772                         continue; /* skip if same as the default */
1773                 if ((want_set &&
1774                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1775                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1776                         continue; /* select Opt_noFoo vs Opt_Foo */
1777                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1778         }
1779
1780         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1781             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1782                 SEQ_OPTS_PRINT("resuid=%u",
1783                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1784         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1785             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1786                 SEQ_OPTS_PRINT("resgid=%u",
1787                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1788         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1789         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1790                 SEQ_OPTS_PUTS("errors=remount-ro");
1791         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1792                 SEQ_OPTS_PUTS("errors=continue");
1793         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1794                 SEQ_OPTS_PUTS("errors=panic");
1795         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1796                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1797         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1798                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1799         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1800                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1801         if (sb->s_flags & MS_I_VERSION)
1802                 SEQ_OPTS_PUTS("i_version");
1803         if (nodefs || sbi->s_stripe)
1804                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1805         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1806                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1807                         SEQ_OPTS_PUTS("data=journal");
1808                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1809                         SEQ_OPTS_PUTS("data=ordered");
1810                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1811                         SEQ_OPTS_PUTS("data=writeback");
1812         }
1813         if (nodefs ||
1814             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1815                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1816                                sbi->s_inode_readahead_blks);
1817
1818         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1819                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1820                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1821
1822         ext4_show_quota_options(seq, sb);
1823         return 0;
1824 }
1825
1826 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1827 {
1828         return _ext4_show_options(seq, root->d_sb, 0);
1829 }
1830
1831 static int options_seq_show(struct seq_file *seq, void *offset)
1832 {
1833         struct super_block *sb = seq->private;
1834         int rc;
1835
1836         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1837         rc = _ext4_show_options(seq, sb, 1);
1838         seq_puts(seq, "\n");
1839         return rc;
1840 }
1841
1842 static int options_open_fs(struct inode *inode, struct file *file)
1843 {
1844         return single_open(file, options_seq_show, PDE(inode)->data);
1845 }
1846
1847 static const struct file_operations ext4_seq_options_fops = {
1848         .owner = THIS_MODULE,
1849         .open = options_open_fs,
1850         .read = seq_read,
1851         .llseek = seq_lseek,
1852         .release = single_release,
1853 };
1854
1855 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1856                             int read_only)
1857 {
1858         struct ext4_sb_info *sbi = EXT4_SB(sb);
1859         int res = 0;
1860
1861         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1862                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1863                          "forcing read-only mode");
1864                 res = MS_RDONLY;
1865         }
1866         if (read_only)
1867                 goto done;
1868         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1869                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1870                          "running e2fsck is recommended");
1871         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1872                 ext4_msg(sb, KERN_WARNING,
1873                          "warning: mounting fs with errors, "
1874                          "running e2fsck is recommended");
1875         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1876                  le16_to_cpu(es->s_mnt_count) >=
1877                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1878                 ext4_msg(sb, KERN_WARNING,
1879                          "warning: maximal mount count reached, "
1880                          "running e2fsck is recommended");
1881         else if (le32_to_cpu(es->s_checkinterval) &&
1882                 (le32_to_cpu(es->s_lastcheck) +
1883                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1884                 ext4_msg(sb, KERN_WARNING,
1885                          "warning: checktime reached, "
1886                          "running e2fsck is recommended");
1887         if (!sbi->s_journal)
1888                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1889         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1890                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1891         le16_add_cpu(&es->s_mnt_count, 1);
1892         es->s_mtime = cpu_to_le32(get_seconds());
1893         ext4_update_dynamic_rev(sb);
1894         if (sbi->s_journal)
1895                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1896
1897         ext4_commit_super(sb, 1);
1898 done:
1899         if (test_opt(sb, DEBUG))
1900                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1901                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1902                         sb->s_blocksize,
1903                         sbi->s_groups_count,
1904                         EXT4_BLOCKS_PER_GROUP(sb),
1905                         EXT4_INODES_PER_GROUP(sb),
1906                         sbi->s_mount_opt, sbi->s_mount_opt2);
1907
1908         cleancache_init_fs(sb);
1909         return res;
1910 }
1911
1912 static int ext4_fill_flex_info(struct super_block *sb)
1913 {
1914         struct ext4_sb_info *sbi = EXT4_SB(sb);
1915         struct ext4_group_desc *gdp = NULL;
1916         ext4_group_t flex_group_count;
1917         ext4_group_t flex_group;
1918         unsigned int groups_per_flex = 0;
1919         size_t size;
1920         int i;
1921
1922         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1923         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1924                 sbi->s_log_groups_per_flex = 0;
1925                 return 1;
1926         }
1927         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1928
1929         /* We allocate both existing and potentially added groups */
1930         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1931                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1932                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1933         size = flex_group_count * sizeof(struct flex_groups);
1934         sbi->s_flex_groups = ext4_kvzalloc(size, GFP_KERNEL);
1935         if (sbi->s_flex_groups == NULL) {
1936                 ext4_msg(sb, KERN_ERR, "not enough memory for %u flex groups",
1937                          flex_group_count);
1938                 goto failed;
1939         }
1940
1941         for (i = 0; i < sbi->s_groups_count; i++) {
1942                 gdp = ext4_get_group_desc(sb, i, NULL);
1943
1944                 flex_group = ext4_flex_group(sbi, i);
1945                 atomic_add(ext4_free_inodes_count(sb, gdp),
1946                            &sbi->s_flex_groups[flex_group].free_inodes);
1947                 atomic_add(ext4_free_group_clusters(sb, gdp),
1948                            &sbi->s_flex_groups[flex_group].free_clusters);
1949                 atomic_add(ext4_used_dirs_count(sb, gdp),
1950                            &sbi->s_flex_groups[flex_group].used_dirs);
1951         }
1952
1953         return 1;
1954 failed:
1955         return 0;
1956 }
1957
1958 static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1959                                    struct ext4_group_desc *gdp)
1960 {
1961         int offset;
1962         __u16 crc = 0;
1963         __le32 le_group = cpu_to_le32(block_group);
1964
1965         if ((sbi->s_es->s_feature_ro_compat &
1966              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))) {
1967                 /* Use new metadata_csum algorithm */
1968                 __u16 old_csum;
1969                 __u32 csum32;
1970
1971                 old_csum = gdp->bg_checksum;
1972                 gdp->bg_checksum = 0;
1973                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
1974                                      sizeof(le_group));
1975                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
1976                                      sbi->s_desc_size);
1977                 gdp->bg_checksum = old_csum;
1978
1979                 crc = csum32 & 0xFFFF;
1980                 goto out;
1981         }
1982
1983         /* old crc16 code */
1984         offset = offsetof(struct ext4_group_desc, bg_checksum);
1985
1986         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1987         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1988         crc = crc16(crc, (__u8 *)gdp, offset);
1989         offset += sizeof(gdp->bg_checksum); /* skip checksum */
1990         /* for checksum of struct ext4_group_desc do the rest...*/
1991         if ((sbi->s_es->s_feature_incompat &
1992              cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1993             offset < le16_to_cpu(sbi->s_es->s_desc_size))
1994                 crc = crc16(crc, (__u8 *)gdp + offset,
1995                             le16_to_cpu(sbi->s_es->s_desc_size) -
1996                                 offset);
1997
1998 out:
1999         return cpu_to_le16(crc);
2000 }
2001
2002 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2003                                 struct ext4_group_desc *gdp)
2004 {
2005         if (ext4_has_group_desc_csum(sb) &&
2006             (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
2007                                                       block_group, gdp)))
2008                 return 0;
2009
2010         return 1;
2011 }
2012
2013 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2014                               struct ext4_group_desc *gdp)
2015 {
2016         if (!ext4_has_group_desc_csum(sb))
2017                 return;
2018         gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
2019 }
2020
2021 /* Called at mount-time, super-block is locked */
2022 static int ext4_check_descriptors(struct super_block *sb,
2023                                   ext4_group_t *first_not_zeroed)
2024 {
2025         struct ext4_sb_info *sbi = EXT4_SB(sb);
2026         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2027         ext4_fsblk_t last_block;
2028         ext4_fsblk_t block_bitmap;
2029         ext4_fsblk_t inode_bitmap;
2030         ext4_fsblk_t inode_table;
2031         int flexbg_flag = 0;
2032         ext4_group_t i, grp = sbi->s_groups_count;
2033
2034         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2035                 flexbg_flag = 1;
2036
2037         ext4_debug("Checking group descriptors");
2038
2039         for (i = 0; i < sbi->s_groups_count; i++) {
2040                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2041
2042                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2043                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2044                 else
2045                         last_block = first_block +
2046                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2047
2048                 if ((grp == sbi->s_groups_count) &&
2049                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2050                         grp = i;
2051
2052                 block_bitmap = ext4_block_bitmap(sb, gdp);
2053                 if (block_bitmap < first_block || block_bitmap > last_block) {
2054                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2055                                "Block bitmap for group %u not in group "
2056                                "(block %llu)!", i, block_bitmap);
2057                         return 0;
2058                 }
2059                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2060                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2061                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2062                                "Inode bitmap for group %u not in group "
2063                                "(block %llu)!", i, inode_bitmap);
2064                         return 0;
2065                 }
2066                 inode_table = ext4_inode_table(sb, gdp);
2067                 if (inode_table < first_block ||
2068                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2069                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2070                                "Inode table for group %u not in group "
2071                                "(block %llu)!", i, inode_table);
2072                         return 0;
2073                 }
2074                 ext4_lock_group(sb, i);
2075                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2076                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2077                                  "Checksum for group %u failed (%u!=%u)",
2078                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2079                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2080                         if (!(sb->s_flags & MS_RDONLY)) {
2081                                 ext4_unlock_group(sb, i);
2082                                 return 0;
2083                         }
2084                 }
2085                 ext4_unlock_group(sb, i);
2086                 if (!flexbg_flag)
2087                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2088         }
2089         if (NULL != first_not_zeroed)
2090                 *first_not_zeroed = grp;
2091
2092         ext4_free_blocks_count_set(sbi->s_es,
2093                                    EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2094         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2095         return 1;
2096 }
2097
2098 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2099  * the superblock) which were deleted from all directories, but held open by
2100  * a process at the time of a crash.  We walk the list and try to delete these
2101  * inodes at recovery time (only with a read-write filesystem).
2102  *
2103  * In order to keep the orphan inode chain consistent during traversal (in
2104  * case of crash during recovery), we link each inode into the superblock
2105  * orphan list_head and handle it the same way as an inode deletion during
2106  * normal operation (which journals the operations for us).
2107  *
2108  * We only do an iget() and an iput() on each inode, which is very safe if we
2109  * accidentally point at an in-use or already deleted inode.  The worst that
2110  * can happen in this case is that we get a "bit already cleared" message from
2111  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2112  * e2fsck was run on this filesystem, and it must have already done the orphan
2113  * inode cleanup for us, so we can safely abort without any further action.
2114  */
2115 static void ext4_orphan_cleanup(struct super_block *sb,
2116                                 struct ext4_super_block *es)
2117 {
2118         unsigned int s_flags = sb->s_flags;
2119         int nr_orphans = 0, nr_truncates = 0;
2120 #ifdef CONFIG_QUOTA
2121         int i;
2122 #endif
2123         if (!es->s_last_orphan) {
2124                 jbd_debug(4, "no orphan inodes to clean up\n");
2125                 return;
2126         }
2127
2128         if (bdev_read_only(sb->s_bdev)) {
2129                 ext4_msg(sb, KERN_ERR, "write access "
2130                         "unavailable, skipping orphan cleanup");
2131                 return;
2132         }
2133
2134         /* Check if feature set would not allow a r/w mount */
2135         if (!ext4_feature_set_ok(sb, 0)) {
2136                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2137                          "unknown ROCOMPAT features");
2138                 return;
2139         }
2140
2141         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2142                 if (es->s_last_orphan)
2143                         jbd_debug(1, "Errors on filesystem, "
2144                                   "clearing orphan list.\n");
2145                 es->s_last_orphan = 0;
2146                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2147                 return;
2148         }
2149
2150         if (s_flags & MS_RDONLY) {
2151                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2152                 sb->s_flags &= ~MS_RDONLY;
2153         }
2154 #ifdef CONFIG_QUOTA
2155         /* Needed for iput() to work correctly and not trash data */
2156         sb->s_flags |= MS_ACTIVE;
2157         /* Turn on quotas so that they are updated correctly */
2158         for (i = 0; i < MAXQUOTAS; i++) {
2159                 if (EXT4_SB(sb)->s_qf_names[i]) {
2160                         int ret = ext4_quota_on_mount(sb, i);
2161                         if (ret < 0)
2162                                 ext4_msg(sb, KERN_ERR,
2163                                         "Cannot turn on journaled "
2164                                         "quota: error %d", ret);
2165                 }
2166         }
2167 #endif
2168
2169         while (es->s_last_orphan) {
2170                 struct inode *inode;
2171
2172                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2173                 if (IS_ERR(inode)) {
2174                         es->s_last_orphan = 0;
2175                         break;
2176                 }
2177
2178                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2179                 dquot_initialize(inode);
2180                 if (inode->i_nlink) {
2181                         ext4_msg(sb, KERN_DEBUG,
2182                                 "%s: truncating inode %lu to %lld bytes",
2183                                 __func__, inode->i_ino, inode->i_size);
2184                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2185                                   inode->i_ino, inode->i_size);
2186                         ext4_truncate(inode);
2187                         nr_truncates++;
2188                 } else {
2189                         ext4_msg(sb, KERN_DEBUG,
2190                                 "%s: deleting unreferenced inode %lu",
2191                                 __func__, inode->i_ino);
2192                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2193                                   inode->i_ino);
2194                         nr_orphans++;
2195                 }
2196                 iput(inode);  /* The delete magic happens here! */
2197         }
2198
2199 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2200
2201         if (nr_orphans)
2202                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2203                        PLURAL(nr_orphans));
2204         if (nr_truncates)
2205                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2206                        PLURAL(nr_truncates));
2207 #ifdef CONFIG_QUOTA
2208         /* Turn quotas off */
2209         for (i = 0; i < MAXQUOTAS; i++) {
2210                 if (sb_dqopt(sb)->files[i])
2211                         dquot_quota_off(sb, i);
2212         }
2213 #endif
2214         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2215 }
2216
2217 /*
2218  * Maximal extent format file size.
2219  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2220  * extent format containers, within a sector_t, and within i_blocks
2221  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2222  * so that won't be a limiting factor.
2223  *
2224  * However there is other limiting factor. We do store extents in the form
2225  * of starting block and length, hence the resulting length of the extent
2226  * covering maximum file size must fit into on-disk format containers as
2227  * well. Given that length is always by 1 unit bigger than max unit (because
2228  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2229  *
2230  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2231  */
2232 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2233 {
2234         loff_t res;
2235         loff_t upper_limit = MAX_LFS_FILESIZE;
2236
2237         /* small i_blocks in vfs inode? */
2238         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2239                 /*
2240                  * CONFIG_LBDAF is not enabled implies the inode
2241                  * i_block represent total blocks in 512 bytes
2242                  * 32 == size of vfs inode i_blocks * 8
2243                  */
2244                 upper_limit = (1LL << 32) - 1;
2245
2246                 /* total blocks in file system block size */
2247                 upper_limit >>= (blkbits - 9);
2248                 upper_limit <<= blkbits;
2249         }
2250
2251         /*
2252          * 32-bit extent-start container, ee_block. We lower the maxbytes
2253          * by one fs block, so ee_len can cover the extent of maximum file
2254          * size
2255          */
2256         res = (1LL << 32) - 1;
2257         res <<= blkbits;
2258
2259         /* Sanity check against vm- & vfs- imposed limits */
2260         if (res > upper_limit)
2261                 res = upper_limit;
2262
2263         return res;
2264 }
2265
2266 /*
2267  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2268  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2269  * We need to be 1 filesystem block less than the 2^48 sector limit.
2270  */
2271 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2272 {
2273         loff_t res = EXT4_NDIR_BLOCKS;
2274         int meta_blocks;
2275         loff_t upper_limit;
2276         /* This is calculated to be the largest file size for a dense, block
2277          * mapped file such that the file's total number of 512-byte sectors,
2278          * including data and all indirect blocks, does not exceed (2^48 - 1).
2279          *
2280          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2281          * number of 512-byte sectors of the file.
2282          */
2283
2284         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2285                 /*
2286                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2287                  * the inode i_block field represents total file blocks in
2288                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2289                  */
2290                 upper_limit = (1LL << 32) - 1;
2291
2292                 /* total blocks in file system block size */
2293                 upper_limit >>= (bits - 9);
2294
2295         } else {
2296                 /*
2297                  * We use 48 bit ext4_inode i_blocks
2298                  * With EXT4_HUGE_FILE_FL set the i_blocks
2299                  * represent total number of blocks in
2300                  * file system block size
2301                  */
2302                 upper_limit = (1LL << 48) - 1;
2303
2304         }
2305
2306         /* indirect blocks */
2307         meta_blocks = 1;
2308         /* double indirect blocks */
2309         meta_blocks += 1 + (1LL << (bits-2));
2310         /* tripple indirect blocks */
2311         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2312
2313         upper_limit -= meta_blocks;
2314         upper_limit <<= bits;
2315
2316         res += 1LL << (bits-2);
2317         res += 1LL << (2*(bits-2));
2318         res += 1LL << (3*(bits-2));
2319         res <<= bits;
2320         if (res > upper_limit)
2321                 res = upper_limit;
2322
2323         if (res > MAX_LFS_FILESIZE)
2324                 res = MAX_LFS_FILESIZE;
2325
2326         return res;
2327 }
2328
2329 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2330                                    ext4_fsblk_t logical_sb_block, int nr)
2331 {
2332         struct ext4_sb_info *sbi = EXT4_SB(sb);
2333         ext4_group_t bg, first_meta_bg;
2334         int has_super = 0;
2335
2336         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2337
2338         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2339             nr < first_meta_bg)
2340                 return logical_sb_block + nr + 1;
2341         bg = sbi->s_desc_per_block * nr;
2342         if (ext4_bg_has_super(sb, bg))
2343                 has_super = 1;
2344
2345         return (has_super + ext4_group_first_block_no(sb, bg));
2346 }
2347
2348 /**
2349  * ext4_get_stripe_size: Get the stripe size.
2350  * @sbi: In memory super block info
2351  *
2352  * If we have specified it via mount option, then
2353  * use the mount option value. If the value specified at mount time is
2354  * greater than the blocks per group use the super block value.
2355  * If the super block value is greater than blocks per group return 0.
2356  * Allocator needs it be less than blocks per group.
2357  *
2358  */
2359 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2360 {
2361         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2362         unsigned long stripe_width =
2363                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2364         int ret;
2365
2366         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2367                 ret = sbi->s_stripe;
2368         else if (stripe_width <= sbi->s_blocks_per_group)
2369                 ret = stripe_width;
2370         else if (stride <= sbi->s_blocks_per_group)
2371                 ret = stride;
2372         else
2373                 ret = 0;
2374
2375         /*
2376          * If the stripe width is 1, this makes no sense and
2377          * we set it to 0 to turn off stripe handling code.
2378          */
2379         if (ret <= 1)
2380                 ret = 0;
2381
2382         return ret;
2383 }
2384
2385 /* sysfs supprt */
2386
2387 struct ext4_attr {
2388         struct attribute attr;
2389         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2390         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2391                          const char *, size_t);
2392         int offset;
2393 };
2394
2395 static int parse_strtoul(const char *buf,
2396                 unsigned long max, unsigned long *value)
2397 {
2398         char *endp;
2399
2400         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2401         endp = skip_spaces(endp);
2402         if (*endp || *value > max)
2403                 return -EINVAL;
2404
2405         return 0;
2406 }
2407
2408 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2409                                               struct ext4_sb_info *sbi,
2410                                               char *buf)
2411 {
2412         return snprintf(buf, PAGE_SIZE, "%llu\n",
2413                 (s64) EXT4_C2B(sbi,
2414                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2415 }
2416
2417 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2418                                          struct ext4_sb_info *sbi, char *buf)
2419 {
2420         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2421
2422         if (!sb->s_bdev->bd_part)
2423                 return snprintf(buf, PAGE_SIZE, "0\n");
2424         return snprintf(buf, PAGE_SIZE, "%lu\n",
2425                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2426                          sbi->s_sectors_written_start) >> 1);
2427 }
2428
2429 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2430                                           struct ext4_sb_info *sbi, char *buf)
2431 {
2432         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2433
2434         if (!sb->s_bdev->bd_part)
2435                 return snprintf(buf, PAGE_SIZE, "0\n");
2436         return snprintf(buf, PAGE_SIZE, "%llu\n",
2437                         (unsigned long long)(sbi->s_kbytes_written +
2438                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2439                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2440 }
2441
2442 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2443                                           struct ext4_sb_info *sbi,
2444                                           const char *buf, size_t count)
2445 {
2446         unsigned long t;
2447
2448         if (parse_strtoul(buf, 0x40000000, &t))
2449                 return -EINVAL;
2450
2451         if (t && !is_power_of_2(t))
2452                 return -EINVAL;
2453
2454         sbi->s_inode_readahead_blks = t;
2455         return count;
2456 }
2457
2458 static ssize_t sbi_ui_show(struct ext4_attr *a,
2459                            struct ext4_sb_info *sbi, char *buf)
2460 {
2461         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2462
2463         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2464 }
2465
2466 static ssize_t sbi_ui_store(struct ext4_attr *a,
2467                             struct ext4_sb_info *sbi,
2468                             const char *buf, size_t count)
2469 {
2470         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2471         unsigned long t;
2472
2473         if (parse_strtoul(buf, 0xffffffff, &t))
2474                 return -EINVAL;
2475         *ui = t;
2476         return count;
2477 }
2478
2479 static ssize_t trigger_test_error(struct ext4_attr *a,
2480                                   struct ext4_sb_info *sbi,
2481                                   const char *buf, size_t count)
2482 {
2483         int len = count;
2484
2485         if (!capable(CAP_SYS_ADMIN))
2486                 return -EPERM;
2487
2488         if (len && buf[len-1] == '\n')
2489                 len--;
2490
2491         if (len)
2492                 ext4_error(sbi->s_sb, "%.*s", len, buf);
2493         return count;
2494 }
2495
2496 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2497 static struct ext4_attr ext4_attr_##_name = {                   \
2498         .attr = {.name = __stringify(_name), .mode = _mode },   \
2499         .show   = _show,                                        \
2500         .store  = _store,                                       \
2501         .offset = offsetof(struct ext4_sb_info, _elname),       \
2502 }
2503 #define EXT4_ATTR(name, mode, show, store) \
2504 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2505
2506 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2507 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2508 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2509 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2510         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2511 #define ATTR_LIST(name) &ext4_attr_##name.attr
2512
2513 EXT4_RO_ATTR(delayed_allocation_blocks);
2514 EXT4_RO_ATTR(session_write_kbytes);
2515 EXT4_RO_ATTR(lifetime_write_kbytes);
2516 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2517                  inode_readahead_blks_store, s_inode_readahead_blks);
2518 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2519 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2520 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2521 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2522 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2523 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2524 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2525 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2526 EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error);
2527
2528 static struct attribute *ext4_attrs[] = {
2529         ATTR_LIST(delayed_allocation_blocks),
2530         ATTR_LIST(session_write_kbytes),
2531         ATTR_LIST(lifetime_write_kbytes),
2532         ATTR_LIST(inode_readahead_blks),
2533         ATTR_LIST(inode_goal),
2534         ATTR_LIST(mb_stats),
2535         ATTR_LIST(mb_max_to_scan),
2536         ATTR_LIST(mb_min_to_scan),
2537         ATTR_LIST(mb_order2_req),
2538         ATTR_LIST(mb_stream_req),
2539         ATTR_LIST(mb_group_prealloc),
2540         ATTR_LIST(max_writeback_mb_bump),
2541         ATTR_LIST(trigger_fs_error),
2542         NULL,
2543 };
2544
2545 /* Features this copy of ext4 supports */
2546 EXT4_INFO_ATTR(lazy_itable_init);
2547 EXT4_INFO_ATTR(batched_discard);
2548
2549 static struct attribute *ext4_feat_attrs[] = {
2550         ATTR_LIST(lazy_itable_init),
2551         ATTR_LIST(batched_discard),
2552         NULL,
2553 };
2554
2555 static ssize_t ext4_attr_show(struct kobject *kobj,
2556                               struct attribute *attr, char *buf)
2557 {
2558         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2559                                                 s_kobj);
2560         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2561
2562         return a->show ? a->show(a, sbi, buf) : 0;
2563 }
2564
2565 static ssize_t ext4_attr_store(struct kobject *kobj,
2566                                struct attribute *attr,
2567                                const char *buf, size_t len)
2568 {
2569         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2570                                                 s_kobj);
2571         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2572
2573         return a->store ? a->store(a, sbi, buf, len) : 0;
2574 }
2575
2576 static void ext4_sb_release(struct kobject *kobj)
2577 {
2578         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2579                                                 s_kobj);
2580         complete(&sbi->s_kobj_unregister);
2581 }
2582
2583 static const struct sysfs_ops ext4_attr_ops = {
2584         .show   = ext4_attr_show,
2585         .store  = ext4_attr_store,
2586 };
2587
2588 static struct kobj_type ext4_ktype = {
2589         .default_attrs  = ext4_attrs,
2590         .sysfs_ops      = &ext4_attr_ops,
2591         .release        = ext4_sb_release,
2592 };
2593
2594 static void ext4_feat_release(struct kobject *kobj)
2595 {
2596         complete(&ext4_feat->f_kobj_unregister);
2597 }
2598
2599 static struct kobj_type ext4_feat_ktype = {
2600         .default_attrs  = ext4_feat_attrs,
2601         .sysfs_ops      = &ext4_attr_ops,
2602         .release        = ext4_feat_release,
2603 };
2604
2605 /*
2606  * Check whether this filesystem can be mounted based on
2607  * the features present and the RDONLY/RDWR mount requested.
2608  * Returns 1 if this filesystem can be mounted as requested,
2609  * 0 if it cannot be.
2610  */
2611 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2612 {
2613         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2614                 ext4_msg(sb, KERN_ERR,
2615                         "Couldn't mount because of "
2616                         "unsupported optional features (%x)",
2617                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2618                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2619                 return 0;
2620         }
2621
2622         if (readonly)
2623                 return 1;
2624
2625         /* Check that feature set is OK for a read-write mount */
2626         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2627                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2628                          "unsupported optional features (%x)",
2629                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2630                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2631                 return 0;
2632         }
2633         /*
2634          * Large file size enabled file system can only be mounted
2635          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2636          */
2637         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2638                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2639                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2640                                  "cannot be mounted RDWR without "
2641                                  "CONFIG_LBDAF");
2642                         return 0;
2643                 }
2644         }
2645         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2646             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2647                 ext4_msg(sb, KERN_ERR,
2648                          "Can't support bigalloc feature without "
2649                          "extents feature\n");
2650                 return 0;
2651         }
2652
2653 #ifndef CONFIG_QUOTA
2654         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
2655             !readonly) {
2656                 ext4_msg(sb, KERN_ERR,
2657                          "Filesystem with quota feature cannot be mounted RDWR "
2658                          "without CONFIG_QUOTA");
2659                 return 0;
2660         }
2661 #endif  /* CONFIG_QUOTA */
2662         return 1;
2663 }
2664
2665 /*
2666  * This function is called once a day if we have errors logged
2667  * on the file system
2668  */
2669 static void print_daily_error_info(unsigned long arg)
2670 {
2671         struct super_block *sb = (struct super_block *) arg;
2672         struct ext4_sb_info *sbi;
2673         struct ext4_super_block *es;
2674
2675         sbi = EXT4_SB(sb);
2676         es = sbi->s_es;
2677
2678         if (es->s_error_count)
2679                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2680                          le32_to_cpu(es->s_error_count));
2681         if (es->s_first_error_time) {
2682                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2683                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2684                        (int) sizeof(es->s_first_error_func),
2685                        es->s_first_error_func,
2686                        le32_to_cpu(es->s_first_error_line));
2687                 if (es->s_first_error_ino)
2688                         printk(": inode %u",
2689                                le32_to_cpu(es->s_first_error_ino));
2690                 if (es->s_first_error_block)
2691                         printk(": block %llu", (unsigned long long)
2692                                le64_to_cpu(es->s_first_error_block));
2693                 printk("\n");
2694         }
2695         if (es->s_last_error_time) {
2696                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2697                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2698                        (int) sizeof(es->s_last_error_func),
2699                        es->s_last_error_func,
2700                        le32_to_cpu(es->s_last_error_line));
2701                 if (es->s_last_error_ino)
2702                         printk(": inode %u",
2703                                le32_to_cpu(es->s_last_error_ino));
2704                 if (es->s_last_error_block)
2705                         printk(": block %llu", (unsigned long long)
2706                                le64_to_cpu(es->s_last_error_block));
2707                 printk("\n");
2708         }
2709         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2710 }
2711
2712 /* Find next suitable group and run ext4_init_inode_table */
2713 static int ext4_run_li_request(struct ext4_li_request *elr)
2714 {
2715         struct ext4_group_desc *gdp = NULL;
2716         ext4_group_t group, ngroups;
2717         struct super_block *sb;
2718         unsigned long timeout = 0;
2719         int ret = 0;
2720
2721         sb = elr->lr_super;
2722         ngroups = EXT4_SB(sb)->s_groups_count;
2723
2724         sb_start_write(sb);
2725         for (group = elr->lr_next_group; group < ngroups; group++) {
2726                 gdp = ext4_get_group_desc(sb, group, NULL);
2727                 if (!gdp) {
2728                         ret = 1;
2729                         break;
2730                 }
2731
2732                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2733                         break;
2734         }
2735
2736         if (group == ngroups)
2737                 ret = 1;
2738
2739         if (!ret) {
2740                 timeout = jiffies;
2741                 ret = ext4_init_inode_table(sb, group,
2742                                             elr->lr_timeout ? 0 : 1);
2743                 if (elr->lr_timeout == 0) {
2744                         timeout = (jiffies - timeout) *
2745                                   elr->lr_sbi->s_li_wait_mult;
2746                         elr->lr_timeout = timeout;
2747                 }
2748                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2749                 elr->lr_next_group = group + 1;
2750         }
2751         sb_end_write(sb);
2752
2753         return ret;
2754 }
2755
2756 /*
2757  * Remove lr_request from the list_request and free the
2758  * request structure. Should be called with li_list_mtx held
2759  */
2760 static void ext4_remove_li_request(struct ext4_li_request *elr)
2761 {
2762         struct ext4_sb_info *sbi;
2763
2764         if (!elr)
2765                 return;
2766
2767         sbi = elr->lr_sbi;
2768
2769         list_del(&elr->lr_request);
2770         sbi->s_li_request = NULL;
2771         kfree(elr);
2772 }
2773
2774 static void ext4_unregister_li_request(struct super_block *sb)
2775 {
2776         mutex_lock(&ext4_li_mtx);
2777         if (!ext4_li_info) {
2778                 mutex_unlock(&ext4_li_mtx);
2779                 return;
2780         }
2781
2782         mutex_lock(&ext4_li_info->li_list_mtx);
2783         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2784         mutex_unlock(&ext4_li_info->li_list_mtx);
2785         mutex_unlock(&ext4_li_mtx);
2786 }
2787
2788 static struct task_struct *ext4_lazyinit_task;
2789
2790 /*
2791  * This is the function where ext4lazyinit thread lives. It walks
2792  * through the request list searching for next scheduled filesystem.
2793  * When such a fs is found, run the lazy initialization request
2794  * (ext4_rn_li_request) and keep track of the time spend in this
2795  * function. Based on that time we compute next schedule time of
2796  * the request. When walking through the list is complete, compute
2797  * next waking time and put itself into sleep.
2798  */
2799 static int ext4_lazyinit_thread(void *arg)
2800 {
2801         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2802         struct list_head *pos, *n;
2803         struct ext4_li_request *elr;
2804         unsigned long next_wakeup, cur;
2805
2806         BUG_ON(NULL == eli);
2807
2808 cont_thread:
2809         while (true) {
2810                 next_wakeup = MAX_JIFFY_OFFSET;
2811
2812                 mutex_lock(&eli->li_list_mtx);
2813                 if (list_empty(&eli->li_request_list)) {
2814                         mutex_unlock(&eli->li_list_mtx);
2815                         goto exit_thread;
2816                 }
2817
2818                 list_for_each_safe(pos, n, &eli->li_request_list) {
2819                         elr = list_entry(pos, struct ext4_li_request,
2820                                          lr_request);
2821
2822                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2823                                 if (ext4_run_li_request(elr) != 0) {
2824                                         /* error, remove the lazy_init job */
2825                                         ext4_remove_li_request(elr);
2826                                         continue;
2827                                 }
2828                         }
2829
2830                         if (time_before(elr->lr_next_sched, next_wakeup))
2831                                 next_wakeup = elr->lr_next_sched;
2832                 }
2833                 mutex_unlock(&eli->li_list_mtx);
2834
2835                 try_to_freeze();
2836
2837                 cur = jiffies;
2838                 if ((time_after_eq(cur, next_wakeup)) ||
2839                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2840                         cond_resched();
2841                         continue;
2842                 }
2843
2844                 schedule_timeout_interruptible(next_wakeup - cur);
2845
2846                 if (kthread_should_stop()) {
2847                         ext4_clear_request_list();
2848                         goto exit_thread;
2849                 }
2850         }
2851
2852 exit_thread:
2853         /*
2854          * It looks like the request list is empty, but we need
2855          * to check it under the li_list_mtx lock, to prevent any
2856          * additions into it, and of course we should lock ext4_li_mtx
2857          * to atomically free the list and ext4_li_info, because at
2858          * this point another ext4 filesystem could be registering
2859          * new one.
2860          */
2861         mutex_lock(&ext4_li_mtx);
2862         mutex_lock(&eli->li_list_mtx);
2863         if (!list_empty(&eli->li_request_list)) {
2864                 mutex_unlock(&eli->li_list_mtx);
2865                 mutex_unlock(&ext4_li_mtx);
2866                 goto cont_thread;
2867         }
2868         mutex_unlock(&eli->li_list_mtx);
2869         kfree(ext4_li_info);
2870         ext4_li_info = NULL;
2871         mutex_unlock(&ext4_li_mtx);
2872
2873         return 0;
2874 }
2875
2876 static void ext4_clear_request_list(void)
2877 {
2878         struct list_head *pos, *n;
2879         struct ext4_li_request *elr;
2880
2881         mutex_lock(&ext4_li_info->li_list_mtx);
2882         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2883                 elr = list_entry(pos, struct ext4_li_request,
2884                                  lr_request);
2885                 ext4_remove_li_request(elr);
2886         }
2887         mutex_unlock(&ext4_li_info->li_list_mtx);
2888 }
2889
2890 static int ext4_run_lazyinit_thread(void)
2891 {
2892         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2893                                          ext4_li_info, "ext4lazyinit");
2894         if (IS_ERR(ext4_lazyinit_task)) {
2895                 int err = PTR_ERR(ext4_lazyinit_task);
2896                 ext4_clear_request_list();
2897                 kfree(ext4_li_info);
2898                 ext4_li_info = NULL;
2899                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
2900                                  "initialization thread\n",
2901                                  err);
2902                 return err;
2903         }
2904         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2905         return 0;
2906 }
2907
2908 /*
2909  * Check whether it make sense to run itable init. thread or not.
2910  * If there is at least one uninitialized inode table, return
2911  * corresponding group number, else the loop goes through all
2912  * groups and return total number of groups.
2913  */
2914 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2915 {
2916         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2917         struct ext4_group_desc *gdp = NULL;
2918
2919         for (group = 0; group < ngroups; group++) {
2920                 gdp = ext4_get_group_desc(sb, group, NULL);
2921                 if (!gdp)
2922                         continue;
2923
2924                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2925                         break;
2926         }
2927
2928         return group;
2929 }
2930
2931 static int ext4_li_info_new(void)
2932 {
2933         struct ext4_lazy_init *eli = NULL;
2934
2935         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2936         if (!eli)
2937                 return -ENOMEM;
2938
2939         INIT_LIST_HEAD(&eli->li_request_list);
2940         mutex_init(&eli->li_list_mtx);
2941
2942         eli->li_state |= EXT4_LAZYINIT_QUIT;
2943
2944         ext4_li_info = eli;
2945
2946         return 0;
2947 }
2948
2949 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2950                                             ext4_group_t start)
2951 {
2952         struct ext4_sb_info *sbi = EXT4_SB(sb);
2953         struct ext4_li_request *elr;
2954         unsigned long rnd;
2955
2956         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2957         if (!elr)
2958                 return NULL;
2959
2960         elr->lr_super = sb;
2961         elr->lr_sbi = sbi;
2962         elr->lr_next_group = start;
2963
2964         /*
2965          * Randomize first schedule time of the request to
2966          * spread the inode table initialization requests
2967          * better.
2968          */
2969         get_random_bytes(&rnd, sizeof(rnd));
2970         elr->lr_next_sched = jiffies + (unsigned long)rnd %
2971                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
2972
2973         return elr;
2974 }
2975
2976 static int ext4_register_li_request(struct super_block *sb,
2977                                     ext4_group_t first_not_zeroed)
2978 {
2979         struct ext4_sb_info *sbi = EXT4_SB(sb);
2980         struct ext4_li_request *elr;
2981         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2982         int ret = 0;
2983
2984         if (sbi->s_li_request != NULL) {
2985                 /*
2986                  * Reset timeout so it can be computed again, because
2987                  * s_li_wait_mult might have changed.
2988                  */
2989                 sbi->s_li_request->lr_timeout = 0;
2990                 return 0;
2991         }
2992
2993         if (first_not_zeroed == ngroups ||
2994             (sb->s_flags & MS_RDONLY) ||
2995             !test_opt(sb, INIT_INODE_TABLE))
2996                 return 0;
2997
2998         elr = ext4_li_request_new(sb, first_not_zeroed);
2999         if (!elr)
3000                 return -ENOMEM;
3001
3002         mutex_lock(&ext4_li_mtx);
3003
3004         if (NULL == ext4_li_info) {
3005                 ret = ext4_li_info_new();
3006                 if (ret)
3007                         goto out;
3008         }
3009
3010         mutex_lock(&ext4_li_info->li_list_mtx);
3011         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3012         mutex_unlock(&ext4_li_info->li_list_mtx);
3013
3014         sbi->s_li_request = elr;
3015         /*
3016          * set elr to NULL here since it has been inserted to
3017          * the request_list and the removal and free of it is
3018          * handled by ext4_clear_request_list from now on.
3019          */
3020         elr = NULL;
3021
3022         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3023                 ret = ext4_run_lazyinit_thread();
3024                 if (ret)
3025                         goto out;
3026         }
3027 out:
3028         mutex_unlock(&ext4_li_mtx);
3029         if (ret)
3030                 kfree(elr);
3031         return ret;
3032 }
3033
3034 /*
3035  * We do not need to lock anything since this is called on
3036  * module unload.
3037  */
3038 static void ext4_destroy_lazyinit_thread(void)
3039 {
3040         /*
3041          * If thread exited earlier
3042          * there's nothing to be done.
3043          */
3044         if (!ext4_li_info || !ext4_lazyinit_task)
3045                 return;
3046
3047         kthread_stop(ext4_lazyinit_task);
3048 }
3049
3050 static int set_journal_csum_feature_set(struct super_block *sb)
3051 {
3052         int ret = 1;
3053         int compat, incompat;
3054         struct ext4_sb_info *sbi = EXT4_SB(sb);
3055
3056         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3057                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3058                 /* journal checksum v2 */
3059                 compat = 0;
3060                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V2;
3061         } else {
3062                 /* journal checksum v1 */
3063                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3064                 incompat = 0;
3065         }
3066
3067         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3068                 ret = jbd2_journal_set_features(sbi->s_journal,
3069                                 compat, 0,
3070                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3071                                 incompat);
3072         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3073                 ret = jbd2_journal_set_features(sbi->s_journal,
3074                                 compat, 0,
3075                                 incompat);
3076                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3077                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3078         } else {
3079                 jbd2_journal_clear_features(sbi->s_journal,
3080                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3081                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3082                                 JBD2_FEATURE_INCOMPAT_CSUM_V2);
3083         }
3084
3085         return ret;
3086 }
3087
3088 /*
3089  * Note: calculating the overhead so we can be compatible with
3090  * historical BSD practice is quite difficult in the face of
3091  * clusters/bigalloc.  This is because multiple metadata blocks from
3092  * different block group can end up in the same allocation cluster.
3093  * Calculating the exact overhead in the face of clustered allocation
3094  * requires either O(all block bitmaps) in memory or O(number of block
3095  * groups**2) in time.  We will still calculate the superblock for
3096  * older file systems --- and if we come across with a bigalloc file
3097  * system with zero in s_overhead_clusters the estimate will be close to
3098  * correct especially for very large cluster sizes --- but for newer
3099  * file systems, it's better to calculate this figure once at mkfs
3100  * time, and store it in the superblock.  If the superblock value is
3101  * present (even for non-bigalloc file systems), we will use it.
3102  */
3103 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3104                           char *buf)
3105 {
3106         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3107         struct ext4_group_desc  *gdp;
3108         ext4_fsblk_t            first_block, last_block, b;
3109         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3110         int                     s, j, count = 0;
3111
3112         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC))
3113                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3114                         sbi->s_itb_per_group + 2);
3115
3116         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3117                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3118         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3119         for (i = 0; i < ngroups; i++) {
3120                 gdp = ext4_get_group_desc(sb, i, NULL);
3121                 b = ext4_block_bitmap(sb, gdp);
3122                 if (b >= first_block && b <= last_block) {
3123                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3124                         count++;
3125                 }
3126                 b = ext4_inode_bitmap(sb, gdp);
3127                 if (b >= first_block && b <= last_block) {
3128                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3129                         count++;
3130                 }
3131                 b = ext4_inode_table(sb, gdp);
3132                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3133                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3134                                 int c = EXT4_B2C(sbi, b - first_block);
3135                                 ext4_set_bit(c, buf);
3136                                 count++;
3137                         }
3138                 if (i != grp)
3139                         continue;
3140                 s = 0;
3141                 if (ext4_bg_has_super(sb, grp)) {
3142                         ext4_set_bit(s++, buf);
3143                         count++;
3144                 }
3145                 for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3146                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3147                         count++;
3148                 }
3149         }
3150         if (!count)
3151                 return 0;
3152         return EXT4_CLUSTERS_PER_GROUP(sb) -
3153                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3154 }
3155
3156 /*
3157  * Compute the overhead and stash it in sbi->s_overhead
3158  */
3159 int ext4_calculate_overhead(struct super_block *sb)
3160 {
3161         struct ext4_sb_info *sbi = EXT4_SB(sb);
3162         struct ext4_super_block *es = sbi->s_es;
3163         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3164         ext4_fsblk_t overhead = 0;
3165         char *buf = (char *) get_zeroed_page(GFP_KERNEL);
3166
3167         memset(buf, 0, PAGE_SIZE);
3168         if (!buf)
3169                 return -ENOMEM;
3170
3171         /*
3172          * Compute the overhead (FS structures).  This is constant
3173          * for a given filesystem unless the number of block groups
3174          * changes so we cache the previous value until it does.
3175          */
3176
3177         /*
3178          * All of the blocks before first_data_block are overhead
3179          */
3180         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3181
3182         /*
3183          * Add the overhead found in each block group
3184          */
3185         for (i = 0; i < ngroups; i++) {
3186                 int blks;
3187
3188                 blks = count_overhead(sb, i, buf);
3189                 overhead += blks;
3190                 if (blks)
3191                         memset(buf, 0, PAGE_SIZE);
3192                 cond_resched();
3193         }
3194         sbi->s_overhead = overhead;
3195         smp_wmb();
3196         free_page((unsigned long) buf);
3197         return 0;
3198 }
3199
3200 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3201 {
3202         char *orig_data = kstrdup(data, GFP_KERNEL);
3203         struct buffer_head *bh;
3204         struct ext4_super_block *es = NULL;
3205         struct ext4_sb_info *sbi;
3206         ext4_fsblk_t block;
3207         ext4_fsblk_t sb_block = get_sb_block(&data);
3208         ext4_fsblk_t logical_sb_block;
3209         unsigned long offset = 0;
3210         unsigned long journal_devnum = 0;
3211         unsigned long def_mount_opts;
3212         struct inode *root;
3213         char *cp;
3214         const char *descr;
3215         int ret = -ENOMEM;
3216         int blocksize, clustersize;
3217         unsigned int db_count;
3218         unsigned int i;
3219         int needs_recovery, has_huge_files, has_bigalloc;
3220         __u64 blocks_count;
3221         int err;
3222         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3223         ext4_group_t first_not_zeroed;
3224
3225         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3226         if (!sbi)
3227                 goto out_free_orig;
3228
3229         sbi->s_blockgroup_lock =
3230                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3231         if (!sbi->s_blockgroup_lock) {
3232                 kfree(sbi);
3233                 goto out_free_orig;
3234         }
3235         sb->s_fs_info = sbi;
3236         sbi->s_sb = sb;
3237         sbi->s_mount_opt = 0;
3238         sbi->s_resuid = make_kuid(&init_user_ns, EXT4_DEF_RESUID);
3239         sbi->s_resgid = make_kgid(&init_user_ns, EXT4_DEF_RESGID);
3240         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3241         sbi->s_sb_block = sb_block;
3242         if (sb->s_bdev->bd_part)
3243                 sbi->s_sectors_written_start =
3244                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3245
3246         /* Cleanup superblock name */
3247         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3248                 *cp = '!';
3249
3250         ret = -EINVAL;
3251         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3252         if (!blocksize) {
3253                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3254                 goto out_fail;
3255         }
3256
3257         /*
3258          * The ext4 superblock will not be buffer aligned for other than 1kB
3259          * block sizes.  We need to calculate the offset from buffer start.
3260          */
3261         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3262                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3263                 offset = do_div(logical_sb_block, blocksize);
3264         } else {
3265                 logical_sb_block = sb_block;
3266         }
3267
3268         if (!(bh = sb_bread(sb, logical_sb_block))) {
3269                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3270                 goto out_fail;
3271         }
3272         /*
3273          * Note: s_es must be initialized as soon as possible because
3274          *       some ext4 macro-instructions depend on its value
3275          */
3276         es = (struct ext4_super_block *) (bh->b_data + offset);
3277         sbi->s_es = es;
3278         sb->s_magic = le16_to_cpu(es->s_magic);
3279         if (sb->s_magic != EXT4_SUPER_MAGIC)
3280                 goto cantfind_ext4;
3281         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3282
3283         /* Warn if metadata_csum and gdt_csum are both set. */
3284         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3285                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
3286             EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
3287                 ext4_warning(sb, KERN_INFO "metadata_csum and uninit_bg are "
3288                              "redundant flags; please run fsck.");
3289
3290         /* Check for a known checksum algorithm */
3291         if (!ext4_verify_csum_type(sb, es)) {
3292                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3293                          "unknown checksum algorithm.");
3294                 silent = 1;
3295                 goto cantfind_ext4;
3296         }
3297
3298         /* Load the checksum driver */
3299         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3300                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3301                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3302                 if (IS_ERR(sbi->s_chksum_driver)) {
3303                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3304                         ret = PTR_ERR(sbi->s_chksum_driver);
3305                         sbi->s_chksum_driver = NULL;
3306                         goto failed_mount;
3307                 }
3308         }
3309
3310         /* Check superblock checksum */
3311         if (!ext4_superblock_csum_verify(sb, es)) {
3312                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3313                          "invalid superblock checksum.  Run e2fsck?");
3314                 silent = 1;
3315                 goto cantfind_ext4;
3316         }
3317
3318         /* Precompute checksum seed for all metadata */
3319         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3320                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
3321                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3322                                                sizeof(es->s_uuid));
3323
3324         /* Set defaults before we parse the mount options */
3325         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3326         set_opt(sb, INIT_INODE_TABLE);
3327         if (def_mount_opts & EXT4_DEFM_DEBUG)
3328                 set_opt(sb, DEBUG);
3329         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3330                 set_opt(sb, GRPID);
3331         if (def_mount_opts & EXT4_DEFM_UID16)
3332                 set_opt(sb, NO_UID32);
3333         /* xattr user namespace & acls are now defaulted on */
3334 #ifdef CONFIG_EXT4_FS_XATTR
3335         set_opt(sb, XATTR_USER);
3336 #endif
3337 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3338         set_opt(sb, POSIX_ACL);
3339 #endif
3340         set_opt(sb, MBLK_IO_SUBMIT);
3341         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3342                 set_opt(sb, JOURNAL_DATA);
3343         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3344                 set_opt(sb, ORDERED_DATA);
3345         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3346                 set_opt(sb, WRITEBACK_DATA);
3347
3348         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3349                 set_opt(sb, ERRORS_PANIC);
3350         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3351                 set_opt(sb, ERRORS_CONT);
3352         else
3353                 set_opt(sb, ERRORS_RO);
3354         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3355                 set_opt(sb, BLOCK_VALIDITY);
3356         if (def_mount_opts & EXT4_DEFM_DISCARD)
3357                 set_opt(sb, DISCARD);
3358
3359         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3360         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3361         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3362         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3363         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3364
3365         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3366                 set_opt(sb, BARRIER);
3367
3368         /*
3369          * enable delayed allocation by default
3370          * Use -o nodelalloc to turn it off
3371          */
3372         if (!IS_EXT3_SB(sb) &&
3373             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3374                 set_opt(sb, DELALLOC);
3375
3376         /*
3377          * set default s_li_wait_mult for lazyinit, for the case there is
3378          * no mount option specified.
3379          */
3380         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3381
3382         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3383                            &journal_devnum, &journal_ioprio, 0)) {
3384                 ext4_msg(sb, KERN_WARNING,
3385                          "failed to parse options in superblock: %s",
3386                          sbi->s_es->s_mount_opts);
3387         }
3388         sbi->s_def_mount_opt = sbi->s_mount_opt;
3389         if (!parse_options((char *) data, sb, &journal_devnum,
3390                            &journal_ioprio, 0))
3391                 goto failed_mount;
3392
3393         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3394                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3395                             "with data=journal disables delayed "
3396                             "allocation and O_DIRECT support!\n");
3397                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3398                         ext4_msg(sb, KERN_ERR, "can't mount with "
3399                                  "both data=journal and delalloc");
3400                         goto failed_mount;
3401                 }
3402                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3403                         ext4_msg(sb, KERN_ERR, "can't mount with "
3404                                  "both data=journal and delalloc");
3405                         goto failed_mount;
3406                 }
3407                 if (test_opt(sb, DELALLOC))
3408                         clear_opt(sb, DELALLOC);
3409         }
3410
3411         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3412         if (test_opt(sb, DIOREAD_NOLOCK)) {
3413                 if (blocksize < PAGE_SIZE) {
3414                         ext4_msg(sb, KERN_ERR, "can't mount with "
3415                                  "dioread_nolock if block size != PAGE_SIZE");
3416                         goto failed_mount;
3417                 }
3418         }
3419
3420         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3421                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3422
3423         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3424             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3425              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3426              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3427                 ext4_msg(sb, KERN_WARNING,
3428                        "feature flags set on rev 0 fs, "
3429                        "running e2fsck is recommended");
3430
3431         if (IS_EXT2_SB(sb)) {
3432                 if (ext2_feature_set_ok(sb))
3433                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3434                                  "using the ext4 subsystem");
3435                 else {
3436                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3437                                  "to feature incompatibilities");
3438                         goto failed_mount;
3439                 }
3440         }
3441
3442         if (IS_EXT3_SB(sb)) {
3443                 if (ext3_feature_set_ok(sb))
3444                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3445                                  "using the ext4 subsystem");
3446                 else {
3447                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3448                                  "to feature incompatibilities");
3449                         goto failed_mount;
3450                 }
3451         }
3452
3453         /*
3454          * Check feature flags regardless of the revision level, since we
3455          * previously didn't change the revision level when setting the flags,
3456          * so there is a chance incompat flags are set on a rev 0 filesystem.
3457          */
3458         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3459                 goto failed_mount;
3460
3461         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3462             blocksize > EXT4_MAX_BLOCK_SIZE) {
3463                 ext4_msg(sb, KERN_ERR,
3464                        "Unsupported filesystem blocksize %d", blocksize);
3465                 goto failed_mount;
3466         }
3467
3468         if (sb->s_blocksize != blocksize) {
3469                 /* Validate the filesystem blocksize */
3470                 if (!sb_set_blocksize(sb, blocksize)) {
3471                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3472                                         blocksize);
3473                         goto failed_mount;
3474                 }
3475
3476                 brelse(bh);
3477                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3478                 offset = do_div(logical_sb_block, blocksize);
3479                 bh = sb_bread(sb, logical_sb_block);
3480                 if (!bh) {
3481                         ext4_msg(sb, KERN_ERR,
3482                                "Can't read superblock on 2nd try");
3483                         goto failed_mount;
3484                 }
3485                 es = (struct ext4_super_block *)(bh->b_data + offset);
3486                 sbi->s_es = es;
3487                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3488                         ext4_msg(sb, KERN_ERR,
3489                                "Magic mismatch, very weird!");
3490                         goto failed_mount;
3491                 }
3492         }
3493
3494         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3495                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3496         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3497                                                       has_huge_files);
3498         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3499
3500         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3501                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3502                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3503         } else {
3504                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3505                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3506                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3507                     (!is_power_of_2(sbi->s_inode_size)) ||
3508                     (sbi->s_inode_size > blocksize)) {
3509                         ext4_msg(sb, KERN_ERR,
3510                                "unsupported inode size: %d",
3511                                sbi->s_inode_size);
3512                         goto failed_mount;
3513                 }
3514                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3515                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3516         }
3517
3518         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3519         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3520                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3521                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3522                     !is_power_of_2(sbi->s_desc_size)) {
3523                         ext4_msg(sb, KERN_ERR,
3524                                "unsupported descriptor size %lu",
3525                                sbi->s_desc_size);
3526                         goto failed_mount;
3527                 }
3528         } else
3529                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3530
3531         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3532         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3533         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3534                 goto cantfind_ext4;
3535
3536         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3537         if (sbi->s_inodes_per_block == 0)
3538                 goto cantfind_ext4;
3539         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3540                                         sbi->s_inodes_per_block;
3541         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3542         sbi->s_sbh = bh;
3543         sbi->s_mount_state = le16_to_cpu(es->s_state);
3544         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3545         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3546
3547         for (i = 0; i < 4; i++)
3548                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3549         sbi->s_def_hash_version = es->s_def_hash_version;
3550         i = le32_to_cpu(es->s_flags);
3551         if (i & EXT2_FLAGS_UNSIGNED_HASH)
3552                 sbi->s_hash_unsigned = 3;
3553         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3554 #ifdef __CHAR_UNSIGNED__
3555                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3556                 sbi->s_hash_unsigned = 3;
3557 #else
3558                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3559 #endif
3560         }
3561
3562         /* Handle clustersize */
3563         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3564         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3565                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3566         if (has_bigalloc) {
3567                 if (clustersize < blocksize) {
3568                         ext4_msg(sb, KERN_ERR,
3569                                  "cluster size (%d) smaller than "
3570                                  "block size (%d)", clustersize, blocksize);
3571                         goto failed_mount;
3572                 }
3573                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3574                         le32_to_cpu(es->s_log_block_size);
3575                 sbi->s_clusters_per_group =
3576                         le32_to_cpu(es->s_clusters_per_group);
3577                 if (sbi->s_clusters_per_group > blocksize * 8) {
3578                         ext4_msg(sb, KERN_ERR,
3579                                  "#clusters per group too big: %lu",
3580                                  sbi->s_clusters_per_group);
3581                         goto failed_mount;
3582                 }
3583                 if (sbi->s_blocks_per_group !=
3584                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3585                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3586                                  "clusters per group (%lu) inconsistent",
3587                                  sbi->s_blocks_per_group,
3588                                  sbi->s_clusters_per_group);
3589                         goto failed_mount;
3590                 }
3591         } else {
3592                 if (clustersize != blocksize) {
3593                         ext4_warning(sb, "fragment/cluster size (%d) != "
3594                                      "block size (%d)", clustersize,
3595                                      blocksize);
3596                         clustersize = blocksize;
3597                 }
3598                 if (sbi->s_blocks_per_group > blocksize * 8) {
3599                         ext4_msg(sb, KERN_ERR,
3600                                  "#blocks per group too big: %lu",
3601                                  sbi->s_blocks_per_group);
3602                         goto failed_mount;
3603                 }
3604                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3605                 sbi->s_cluster_bits = 0;
3606         }
3607         sbi->s_cluster_ratio = clustersize / blocksize;
3608
3609         if (sbi->s_inodes_per_group > blocksize * 8) {
3610                 ext4_msg(sb, KERN_ERR,
3611                        "#inodes per group too big: %lu",
3612                        sbi->s_inodes_per_group);
3613                 goto failed_mount;
3614         }
3615
3616         /*
3617          * Test whether we have more sectors than will fit in sector_t,
3618          * and whether the max offset is addressable by the page cache.
3619          */
3620         err = generic_check_addressable(sb->s_blocksize_bits,
3621                                         ext4_blocks_count(es));
3622         if (err) {
3623                 ext4_msg(sb, KERN_ERR, "filesystem"
3624                          " too large to mount safely on this system");
3625                 if (sizeof(sector_t) < 8)
3626                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3627                 ret = err;
3628                 goto failed_mount;
3629         }
3630
3631         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3632                 goto cantfind_ext4;
3633
3634         /* check blocks count against device size */
3635         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3636         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3637                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3638                        "exceeds size of device (%llu blocks)",
3639                        ext4_blocks_count(es), blocks_count);
3640                 goto failed_mount;
3641         }
3642
3643         /*
3644          * It makes no sense for the first data block to be beyond the end
3645          * of the filesystem.
3646          */
3647         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3648                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3649                          "block %u is beyond end of filesystem (%llu)",
3650                          le32_to_cpu(es->s_first_data_block),
3651                          ext4_blocks_count(es));
3652                 goto failed_mount;
3653         }
3654         blocks_count = (ext4_blocks_count(es) -
3655                         le32_to_cpu(es->s_first_data_block) +
3656                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3657         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3658         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3659                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3660                        "(block count %llu, first data block %u, "
3661                        "blocks per group %lu)", sbi->s_groups_count,
3662                        ext4_blocks_count(es),
3663                        le32_to_cpu(es->s_first_data_block),
3664                        EXT4_BLOCKS_PER_GROUP(sb));
3665                 goto failed_mount;
3666         }
3667         sbi->s_groups_count = blocks_count;
3668         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3669                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3670         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3671                    EXT4_DESC_PER_BLOCK(sb);
3672         sbi->s_group_desc = ext4_kvmalloc(db_count *
3673                                           sizeof(struct buffer_head *),
3674                                           GFP_KERNEL);
3675         if (sbi->s_group_desc == NULL) {
3676                 ext4_msg(sb, KERN_ERR, "not enough memory");
3677                 ret = -ENOMEM;
3678                 goto failed_mount;
3679         }
3680
3681         if (ext4_proc_root)
3682                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3683
3684         if (sbi->s_proc)
3685                 proc_create_data("options", S_IRUGO, sbi->s_proc,
3686                                  &ext4_seq_options_fops, sb);
3687
3688         bgl_lock_init(sbi->s_blockgroup_lock);
3689
3690         for (i = 0; i < db_count; i++) {
3691                 block = descriptor_loc(sb, logical_sb_block, i);
3692                 sbi->s_group_desc[i] = sb_bread(sb, block);
3693                 if (!sbi->s_group_desc[i]) {
3694                         ext4_msg(sb, KERN_ERR,
3695                                "can't read group descriptor %d", i);
3696                         db_count = i;
3697                         goto failed_mount2;
3698                 }
3699         }
3700         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3701                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3702                 goto failed_mount2;
3703         }
3704         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3705                 if (!ext4_fill_flex_info(sb)) {
3706                         ext4_msg(sb, KERN_ERR,
3707                                "unable to initialize "
3708                                "flex_bg meta info!");
3709                         goto failed_mount2;
3710                 }
3711
3712         sbi->s_gdb_count = db_count;
3713         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3714         spin_lock_init(&sbi->s_next_gen_lock);
3715
3716         init_timer(&sbi->s_err_report);
3717         sbi->s_err_report.function = print_daily_error_info;
3718         sbi->s_err_report.data = (unsigned long) sb;
3719
3720         err = percpu_counter_init(&sbi->s_freeclusters_counter,
3721                         ext4_count_free_clusters(sb));
3722         if (!err) {
3723                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
3724                                 ext4_count_free_inodes(sb));
3725         }
3726         if (!err) {
3727                 err = percpu_counter_init(&sbi->s_dirs_counter,
3728                                 ext4_count_dirs(sb));
3729         }
3730         if (!err) {
3731                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0);
3732         }
3733         if (err) {
3734                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3735                 ret = err;
3736                 goto failed_mount3;
3737         }
3738
3739         sbi->s_stripe = ext4_get_stripe_size(sbi);
3740         sbi->s_max_writeback_mb_bump = 128;
3741
3742         /*
3743          * set up enough so that it can read an inode
3744          */
3745         if (!test_opt(sb, NOLOAD) &&
3746             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3747                 sb->s_op = &ext4_sops;
3748         else
3749                 sb->s_op = &ext4_nojournal_sops;
3750         sb->s_export_op = &ext4_export_ops;
3751         sb->s_xattr = ext4_xattr_handlers;
3752 #ifdef CONFIG_QUOTA
3753         sb->s_qcop = &ext4_qctl_operations;
3754         sb->dq_op = &ext4_quota_operations;
3755
3756         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) {
3757                 /* Use qctl operations for hidden quota files. */
3758                 sb->s_qcop = &ext4_qctl_sysfile_operations;
3759         }
3760 #endif
3761         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3762
3763         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3764         mutex_init(&sbi->s_orphan_lock);
3765         sbi->s_resize_flags = 0;
3766
3767         sb->s_root = NULL;
3768
3769         needs_recovery = (es->s_last_orphan != 0 ||
3770                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3771                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3772
3773         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3774             !(sb->s_flags & MS_RDONLY))
3775                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3776                         goto failed_mount3;
3777
3778         /*
3779          * The first inode we look at is the journal inode.  Don't try
3780          * root first: it may be modified in the journal!
3781          */
3782         if (!test_opt(sb, NOLOAD) &&
3783             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3784                 if (ext4_load_journal(sb, es, journal_devnum))
3785                         goto failed_mount3;
3786         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3787               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3788                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3789                        "suppressed and not mounted read-only");
3790                 goto failed_mount_wq;
3791         } else {
3792                 clear_opt(sb, DATA_FLAGS);
3793                 sbi->s_journal = NULL;
3794                 needs_recovery = 0;
3795                 goto no_journal;
3796         }
3797
3798         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) &&
3799             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3800                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3801                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3802                 goto failed_mount_wq;
3803         }
3804
3805         if (!set_journal_csum_feature_set(sb)) {
3806                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
3807                          "feature set");
3808                 goto failed_mount_wq;
3809         }
3810
3811         /* We have now updated the journal if required, so we can
3812          * validate the data journaling mode. */
3813         switch (test_opt(sb, DATA_FLAGS)) {
3814         case 0:
3815                 /* No mode set, assume a default based on the journal
3816                  * capabilities: ORDERED_DATA if the journal can
3817                  * cope, else JOURNAL_DATA
3818                  */
3819                 if (jbd2_journal_check_available_features
3820                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3821                         set_opt(sb, ORDERED_DATA);
3822                 else
3823                         set_opt(sb, JOURNAL_DATA);
3824                 break;
3825
3826         case EXT4_MOUNT_ORDERED_DATA:
3827         case EXT4_MOUNT_WRITEBACK_DATA:
3828                 if (!jbd2_journal_check_available_features
3829                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3830                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3831                                "requested data journaling mode");
3832                         goto failed_mount_wq;
3833                 }
3834         default:
3835                 break;
3836         }
3837         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3838
3839         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
3840
3841         /*
3842          * The journal may have updated the bg summary counts, so we
3843          * need to update the global counters.
3844          */
3845         percpu_counter_set(&sbi->s_freeclusters_counter,
3846                            ext4_count_free_clusters(sb));
3847         percpu_counter_set(&sbi->s_freeinodes_counter,
3848                            ext4_count_free_inodes(sb));
3849         percpu_counter_set(&sbi->s_dirs_counter,
3850                            ext4_count_dirs(sb));
3851         percpu_counter_set(&sbi->s_dirtyclusters_counter, 0);
3852
3853 no_journal:
3854         /*
3855          * Get the # of file system overhead blocks from the
3856          * superblock if present.
3857          */
3858         if (es->s_overhead_clusters)
3859                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
3860         else {
3861                 ret = ext4_calculate_overhead(sb);
3862                 if (ret)
3863                         goto failed_mount_wq;
3864         }
3865
3866         /*
3867          * The maximum number of concurrent works can be high and
3868          * concurrency isn't really necessary.  Limit it to 1.
3869          */
3870         EXT4_SB(sb)->dio_unwritten_wq =
3871                 alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
3872         if (!EXT4_SB(sb)->dio_unwritten_wq) {
3873                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
3874                 goto failed_mount_wq;
3875         }
3876
3877         /*
3878          * The jbd2_journal_load will have done any necessary log recovery,
3879          * so we can safely mount the rest of the filesystem now.
3880          */
3881
3882         root = ext4_iget(sb, EXT4_ROOT_INO);
3883         if (IS_ERR(root)) {
3884                 ext4_msg(sb, KERN_ERR, "get root inode failed");
3885                 ret = PTR_ERR(root);
3886                 root = NULL;
3887                 goto failed_mount4;
3888         }
3889         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3890                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3891                 iput(root);
3892                 goto failed_mount4;
3893         }
3894         sb->s_root = d_make_root(root);
3895         if (!sb->s_root) {
3896                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
3897                 ret = -ENOMEM;
3898                 goto failed_mount4;
3899         }
3900
3901         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
3902                 sb->s_flags |= MS_RDONLY;
3903
3904         /* determine the minimum size of new large inodes, if present */
3905         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3906                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3907                                                      EXT4_GOOD_OLD_INODE_SIZE;
3908                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3909                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
3910                         if (sbi->s_want_extra_isize <
3911                             le16_to_cpu(es->s_want_extra_isize))
3912                                 sbi->s_want_extra_isize =
3913                                         le16_to_cpu(es->s_want_extra_isize);
3914                         if (sbi->s_want_extra_isize <
3915                             le16_to_cpu(es->s_min_extra_isize))
3916                                 sbi->s_want_extra_isize =
3917                                         le16_to_cpu(es->s_min_extra_isize);
3918                 }
3919         }
3920         /* Check if enough inode space is available */
3921         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3922                                                         sbi->s_inode_size) {
3923                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3924                                                        EXT4_GOOD_OLD_INODE_SIZE;
3925                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
3926                          "available");
3927         }
3928
3929         err = ext4_setup_system_zone(sb);
3930         if (err) {
3931                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3932                          "zone (%d)", err);
3933                 goto failed_mount4a;
3934         }
3935
3936         ext4_ext_init(sb);
3937         err = ext4_mb_init(sb);
3938         if (err) {
3939                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3940                          err);
3941                 goto failed_mount5;
3942         }
3943
3944         err = ext4_register_li_request(sb, first_not_zeroed);
3945         if (err)
3946                 goto failed_mount6;
3947
3948         sbi->s_kobj.kset = ext4_kset;
3949         init_completion(&sbi->s_kobj_unregister);
3950         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3951                                    "%s", sb->s_id);
3952         if (err)
3953                 goto failed_mount7;
3954
3955         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3956         ext4_orphan_cleanup(sb, es);
3957         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3958         if (needs_recovery) {
3959                 ext4_msg(sb, KERN_INFO, "recovery complete");
3960                 ext4_mark_recovery_complete(sb, es);
3961         }
3962         if (EXT4_SB(sb)->s_journal) {
3963                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3964                         descr = " journalled data mode";
3965                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3966                         descr = " ordered data mode";
3967                 else
3968                         descr = " writeback data mode";
3969         } else
3970                 descr = "out journal";
3971
3972 #ifdef CONFIG_QUOTA
3973         /* Enable quota usage during mount. */
3974         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
3975             !(sb->s_flags & MS_RDONLY)) {
3976                 ret = ext4_enable_quotas(sb);
3977                 if (ret)
3978                         goto failed_mount7;
3979         }
3980 #endif  /* CONFIG_QUOTA */
3981
3982         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3983                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
3984                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
3985
3986         if (es->s_error_count)
3987                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
3988
3989         kfree(orig_data);
3990         return 0;
3991
3992 cantfind_ext4:
3993         if (!silent)
3994                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3995         goto failed_mount;
3996
3997 failed_mount7:
3998         ext4_unregister_li_request(sb);
3999 failed_mount6:
4000         ext4_mb_release(sb);
4001 failed_mount5:
4002         ext4_ext_release(sb);
4003         ext4_release_system_zone(sb);
4004 failed_mount4a:
4005         dput(sb->s_root);
4006         sb->s_root = NULL;
4007 failed_mount4:
4008         ext4_msg(sb, KERN_ERR, "mount failed");
4009         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
4010 failed_mount_wq:
4011         if (sbi->s_journal) {
4012                 jbd2_journal_destroy(sbi->s_journal);
4013                 sbi->s_journal = NULL;
4014         }
4015 failed_mount3:
4016         del_timer(&sbi->s_err_report);
4017         if (sbi->s_flex_groups)
4018                 ext4_kvfree(sbi->s_flex_groups);
4019         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4020         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4021         percpu_counter_destroy(&sbi->s_dirs_counter);
4022         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4023         if (sbi->s_mmp_tsk)
4024                 kthread_stop(sbi->s_mmp_tsk);
4025 failed_mount2:
4026         for (i = 0; i < db_count; i++)
4027                 brelse(sbi->s_group_desc[i]);
4028         ext4_kvfree(sbi->s_group_desc);
4029 failed_mount:
4030         if (sbi->s_chksum_driver)
4031                 crypto_free_shash(sbi->s_chksum_driver);
4032         if (sbi->s_proc) {
4033                 remove_proc_entry("options", sbi->s_proc);
4034                 remove_proc_entry(sb->s_id, ext4_proc_root);
4035         }
4036 #ifdef CONFIG_QUOTA
4037         for (i = 0; i < MAXQUOTAS; i++)
4038                 kfree(sbi->s_qf_names[i]);
4039 #endif
4040         ext4_blkdev_remove(sbi);
4041         brelse(bh);
4042 out_fail:
4043         sb->s_fs_info = NULL;
4044         kfree(sbi->s_blockgroup_lock);
4045         kfree(sbi);
4046 out_free_orig:
4047         kfree(orig_data);
4048         return ret;
4049 }
4050
4051 /*
4052  * Setup any per-fs journal parameters now.  We'll do this both on
4053  * initial mount, once the journal has been initialised but before we've
4054  * done any recovery; and again on any subsequent remount.
4055  */
4056 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4057 {
4058         struct ext4_sb_info *sbi = EXT4_SB(sb);
4059
4060         journal->j_commit_interval = sbi->s_commit_interval;
4061         journal->j_min_batch_time = sbi->s_min_batch_time;
4062         journal->j_max_batch_time = sbi->s_max_batch_time;
4063
4064         write_lock(&journal->j_state_lock);
4065         if (test_opt(sb, BARRIER))
4066                 journal->j_flags |= JBD2_BARRIER;
4067         else
4068                 journal->j_flags &= ~JBD2_BARRIER;
4069         if (test_opt(sb, DATA_ERR_ABORT))
4070                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4071         else
4072                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4073         write_unlock(&journal->j_state_lock);
4074 }
4075
4076 static journal_t *ext4_get_journal(struct super_block *sb,
4077                                    unsigned int journal_inum)
4078 {
4079         struct inode *journal_inode;
4080         journal_t *journal;
4081
4082         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4083
4084         /* First, test for the existence of a valid inode on disk.  Bad
4085          * things happen if we iget() an unused inode, as the subsequent
4086          * iput() will try to delete it. */
4087
4088         journal_inode = ext4_iget(sb, journal_inum);
4089         if (IS_ERR(journal_inode)) {
4090                 ext4_msg(sb, KERN_ERR, "no journal found");
4091                 return NULL;
4092         }
4093         if (!journal_inode->i_nlink) {
4094                 make_bad_inode(journal_inode);
4095                 iput(journal_inode);
4096                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4097                 return NULL;
4098         }
4099
4100         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4101                   journal_inode, journal_inode->i_size);
4102         if (!S_ISREG(journal_inode->i_mode)) {
4103                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4104                 iput(journal_inode);
4105                 return NULL;
4106         }
4107
4108         journal = jbd2_journal_init_inode(journal_inode);
4109         if (!journal) {
4110                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4111                 iput(journal_inode);
4112                 return NULL;
4113         }
4114         journal->j_private = sb;
4115         ext4_init_journal_params(sb, journal);
4116         return journal;
4117 }
4118
4119 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4120                                        dev_t j_dev)
4121 {
4122         struct buffer_head *bh;
4123         journal_t *journal;
4124         ext4_fsblk_t start;
4125         ext4_fsblk_t len;
4126         int hblock, blocksize;
4127         ext4_fsblk_t sb_block;
4128         unsigned long offset;
4129         struct ext4_super_block *es;
4130         struct block_device *bdev;
4131
4132         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4133
4134         bdev = ext4_blkdev_get(j_dev, sb);
4135         if (bdev == NULL)
4136                 return NULL;
4137
4138         blocksize = sb->s_blocksize;
4139         hblock = bdev_logical_block_size(bdev);
4140         if (blocksize < hblock) {
4141                 ext4_msg(sb, KERN_ERR,
4142                         "blocksize too small for journal device");
4143                 goto out_bdev;
4144         }
4145
4146         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4147         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4148         set_blocksize(bdev, blocksize);
4149         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4150                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4151                        "external journal");
4152                 goto out_bdev;
4153         }
4154
4155         es = (struct ext4_super_block *) (bh->b_data + offset);
4156         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4157             !(le32_to_cpu(es->s_feature_incompat) &
4158               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4159                 ext4_msg(sb, KERN_ERR, "external journal has "
4160                                         "bad superblock");
4161                 brelse(bh);
4162                 goto out_bdev;
4163         }
4164
4165         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4166                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4167                 brelse(bh);
4168                 goto out_bdev;
4169         }
4170
4171         len = ext4_blocks_count(es);
4172         start = sb_block + 1;
4173         brelse(bh);     /* we're done with the superblock */
4174
4175         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4176                                         start, len, blocksize);
4177         if (!journal) {
4178                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4179                 goto out_bdev;
4180         }
4181         journal->j_private = sb;
4182         ll_rw_block(READ, 1, &journal->j_sb_buffer);
4183         wait_on_buffer(journal->j_sb_buffer);
4184         if (!buffer_uptodate(journal->j_sb_buffer)) {
4185                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4186                 goto out_journal;
4187         }
4188         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4189                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4190                                         "user (unsupported) - %d",
4191                         be32_to_cpu(journal->j_superblock->s_nr_users));
4192                 goto out_journal;
4193         }
4194         EXT4_SB(sb)->journal_bdev = bdev;
4195         ext4_init_journal_params(sb, journal);
4196         return journal;
4197
4198 out_journal:
4199         jbd2_journal_destroy(journal);
4200 out_bdev:
4201         ext4_blkdev_put(bdev);
4202         return NULL;
4203 }
4204
4205 static int ext4_load_journal(struct super_block *sb,
4206                              struct ext4_super_block *es,
4207                              unsigned long journal_devnum)
4208 {
4209         journal_t *journal;
4210         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4211         dev_t journal_dev;
4212         int err = 0;
4213         int really_read_only;
4214
4215         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4216
4217         if (journal_devnum &&
4218             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4219                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4220                         "numbers have changed");
4221                 journal_dev = new_decode_dev(journal_devnum);
4222         } else
4223                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4224
4225         really_read_only = bdev_read_only(sb->s_bdev);
4226
4227         /*
4228          * Are we loading a blank journal or performing recovery after a
4229          * crash?  For recovery, we need to check in advance whether we
4230          * can get read-write access to the device.
4231          */
4232         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4233                 if (sb->s_flags & MS_RDONLY) {
4234                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4235                                         "required on readonly filesystem");
4236                         if (really_read_only) {
4237                                 ext4_msg(sb, KERN_ERR, "write access "
4238                                         "unavailable, cannot proceed");
4239                                 return -EROFS;
4240                         }
4241                         ext4_msg(sb, KERN_INFO, "write access will "
4242                                "be enabled during recovery");
4243                 }
4244         }
4245
4246         if (journal_inum && journal_dev) {
4247                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4248                        "and inode journals!");
4249                 return -EINVAL;
4250         }
4251
4252         if (journal_inum) {
4253                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4254                         return -EINVAL;
4255         } else {
4256                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4257                         return -EINVAL;
4258         }
4259
4260         if (!(journal->j_flags & JBD2_BARRIER))
4261                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4262
4263         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4264                 err = jbd2_journal_wipe(journal, !really_read_only);
4265         if (!err) {
4266                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4267                 if (save)
4268                         memcpy(save, ((char *) es) +
4269                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4270                 err = jbd2_journal_load(journal);
4271                 if (save)
4272                         memcpy(((char *) es) + EXT4_S_ERR_START,
4273                                save, EXT4_S_ERR_LEN);
4274                 kfree(save);
4275         }
4276
4277         if (err) {
4278                 ext4_msg(sb, KERN_ERR, "error loading journal");
4279                 jbd2_journal_destroy(journal);
4280                 return err;
4281         }
4282
4283         EXT4_SB(sb)->s_journal = journal;
4284         ext4_clear_journal_err(sb, es);
4285
4286         if (!really_read_only && journal_devnum &&
4287             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4288                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4289
4290                 /* Make sure we flush the recovery flag to disk. */
4291                 ext4_commit_super(sb, 1);
4292         }
4293
4294         return 0;
4295 }
4296
4297 static int ext4_commit_super(struct super_block *sb, int sync)
4298 {
4299         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4300         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4301         int error = 0;
4302
4303         if (!sbh || block_device_ejected(sb))
4304                 return error;
4305         if (buffer_write_io_error(sbh)) {
4306                 /*
4307                  * Oh, dear.  A previous attempt to write the
4308                  * superblock failed.  This could happen because the
4309                  * USB device was yanked out.  Or it could happen to
4310                  * be a transient write error and maybe the block will
4311                  * be remapped.  Nothing we can do but to retry the
4312                  * write and hope for the best.
4313                  */
4314                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4315                        "superblock detected");
4316                 clear_buffer_write_io_error(sbh);
4317                 set_buffer_uptodate(sbh);
4318         }
4319         /*
4320          * If the file system is mounted read-only, don't update the
4321          * superblock write time.  This avoids updating the superblock
4322          * write time when we are mounting the root file system
4323          * read/only but we need to replay the journal; at that point,
4324          * for people who are east of GMT and who make their clock
4325          * tick in localtime for Windows bug-for-bug compatibility,
4326          * the clock is set in the future, and this will cause e2fsck
4327          * to complain and force a full file system check.
4328          */
4329         if (!(sb->s_flags & MS_RDONLY))
4330                 es->s_wtime = cpu_to_le32(get_seconds());
4331         if (sb->s_bdev->bd_part)
4332                 es->s_kbytes_written =
4333                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4334                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4335                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4336         else
4337                 es->s_kbytes_written =
4338                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4339         ext4_free_blocks_count_set(es,
4340                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4341                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4342         es->s_free_inodes_count =
4343                 cpu_to_le32(percpu_counter_sum_positive(
4344                                 &EXT4_SB(sb)->s_freeinodes_counter));
4345         BUFFER_TRACE(sbh, "marking dirty");
4346         ext4_superblock_csum_set(sb, es);
4347         mark_buffer_dirty(sbh);
4348         if (sync) {
4349                 error = sync_dirty_buffer(sbh);
4350                 if (error)
4351                         return error;
4352
4353                 error = buffer_write_io_error(sbh);
4354                 if (error) {
4355                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4356                                "superblock");
4357                         clear_buffer_write_io_error(sbh);
4358                         set_buffer_uptodate(sbh);
4359                 }
4360         }
4361         return error;
4362 }
4363
4364 /*
4365  * Have we just finished recovery?  If so, and if we are mounting (or
4366  * remounting) the filesystem readonly, then we will end up with a
4367  * consistent fs on disk.  Record that fact.
4368  */
4369 static void ext4_mark_recovery_complete(struct super_block *sb,
4370                                         struct ext4_super_block *es)
4371 {
4372         journal_t *journal = EXT4_SB(sb)->s_journal;
4373
4374         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4375                 BUG_ON(journal != NULL);
4376                 return;
4377         }
4378         jbd2_journal_lock_updates(journal);
4379         if (jbd2_journal_flush(journal) < 0)
4380                 goto out;
4381
4382         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4383             sb->s_flags & MS_RDONLY) {
4384                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4385                 ext4_commit_super(sb, 1);
4386         }
4387
4388 out:
4389         jbd2_journal_unlock_updates(journal);
4390 }
4391
4392 /*
4393  * If we are mounting (or read-write remounting) a filesystem whose journal
4394  * has recorded an error from a previous lifetime, move that error to the
4395  * main filesystem now.
4396  */
4397 static void ext4_clear_journal_err(struct super_block *sb,
4398                                    struct ext4_super_block *es)
4399 {
4400         journal_t *journal;
4401         int j_errno;
4402         const char *errstr;
4403
4404         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4405
4406         journal = EXT4_SB(sb)->s_journal;
4407
4408         /*
4409          * Now check for any error status which may have been recorded in the
4410          * journal by a prior ext4_error() or ext4_abort()
4411          */
4412
4413         j_errno = jbd2_journal_errno(journal);
4414         if (j_errno) {
4415                 char nbuf[16];
4416
4417                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4418                 ext4_warning(sb, "Filesystem error recorded "
4419                              "from previous mount: %s", errstr);
4420                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4421
4422                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4423                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4424                 ext4_commit_super(sb, 1);
4425
4426                 jbd2_journal_clear_err(journal);
4427                 jbd2_journal_update_sb_errno(journal);
4428         }
4429 }
4430
4431 /*
4432  * Force the running and committing transactions to commit,
4433  * and wait on the commit.
4434  */
4435 int ext4_force_commit(struct super_block *sb)
4436 {
4437         journal_t *journal;
4438         int ret = 0;
4439
4440         if (sb->s_flags & MS_RDONLY)
4441                 return 0;
4442
4443         journal = EXT4_SB(sb)->s_journal;
4444         if (journal)
4445                 ret = ext4_journal_force_commit(journal);
4446
4447         return ret;
4448 }
4449
4450 static int ext4_sync_fs(struct super_block *sb, int wait)
4451 {
4452         int ret = 0;
4453         tid_t target;
4454         struct ext4_sb_info *sbi = EXT4_SB(sb);
4455
4456         trace_ext4_sync_fs(sb, wait);
4457         flush_workqueue(sbi->dio_unwritten_wq);
4458         /*
4459          * Writeback quota in non-journalled quota case - journalled quota has
4460          * no dirty dquots
4461          */
4462         dquot_writeback_dquots(sb, -1);
4463         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4464                 if (wait)
4465                         jbd2_log_wait_commit(sbi->s_journal, target);
4466         }
4467         return ret;
4468 }
4469
4470 /*
4471  * LVM calls this function before a (read-only) snapshot is created.  This
4472  * gives us a chance to flush the journal completely and mark the fs clean.
4473  *
4474  * Note that only this function cannot bring a filesystem to be in a clean
4475  * state independently. It relies on upper layer to stop all data & metadata
4476  * modifications.
4477  */
4478 static int ext4_freeze(struct super_block *sb)
4479 {
4480         int error = 0;
4481         journal_t *journal;
4482
4483         if (sb->s_flags & MS_RDONLY)
4484                 return 0;
4485
4486         journal = EXT4_SB(sb)->s_journal;
4487
4488         /* Now we set up the journal barrier. */
4489         jbd2_journal_lock_updates(journal);
4490
4491         /*
4492          * Don't clear the needs_recovery flag if we failed to flush
4493          * the journal.
4494          */
4495         error = jbd2_journal_flush(journal);
4496         if (error < 0)
4497                 goto out;
4498
4499         /* Journal blocked and flushed, clear needs_recovery flag. */
4500         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4501         error = ext4_commit_super(sb, 1);
4502 out:
4503         /* we rely on upper layer to stop further updates */
4504         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4505         return error;
4506 }
4507
4508 /*
4509  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4510  * flag here, even though the filesystem is not technically dirty yet.
4511  */
4512 static int ext4_unfreeze(struct super_block *sb)
4513 {
4514         if (sb->s_flags & MS_RDONLY)
4515                 return 0;
4516
4517         lock_super(sb);
4518         /* Reset the needs_recovery flag before the fs is unlocked. */
4519         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4520         ext4_commit_super(sb, 1);
4521         unlock_super(sb);
4522         return 0;
4523 }
4524
4525 /*
4526  * Structure to save mount options for ext4_remount's benefit
4527  */
4528 struct ext4_mount_options {
4529         unsigned long s_mount_opt;
4530         unsigned long s_mount_opt2;
4531         kuid_t s_resuid;
4532         kgid_t s_resgid;
4533         unsigned long s_commit_interval;
4534         u32 s_min_batch_time, s_max_batch_time;
4535 #ifdef CONFIG_QUOTA
4536         int s_jquota_fmt;
4537         char *s_qf_names[MAXQUOTAS];
4538 #endif
4539 };
4540
4541 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4542 {
4543         struct ext4_super_block *es;
4544         struct ext4_sb_info *sbi = EXT4_SB(sb);
4545         unsigned long old_sb_flags;
4546         struct ext4_mount_options old_opts;
4547         int enable_quota = 0;
4548         ext4_group_t g;
4549         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4550         int err = 0;
4551 #ifdef CONFIG_QUOTA
4552         int i;
4553 #endif
4554         char *orig_data = kstrdup(data, GFP_KERNEL);
4555
4556         /* Store the original options */
4557         lock_super(sb);
4558         old_sb_flags = sb->s_flags;
4559         old_opts.s_mount_opt = sbi->s_mount_opt;
4560         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4561         old_opts.s_resuid = sbi->s_resuid;
4562         old_opts.s_resgid = sbi->s_resgid;
4563         old_opts.s_commit_interval = sbi->s_commit_interval;
4564         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4565         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4566 #ifdef CONFIG_QUOTA
4567         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4568         for (i = 0; i < MAXQUOTAS; i++)
4569                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
4570 #endif
4571         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4572                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4573
4574         /*
4575          * Allow the "check" option to be passed as a remount option.
4576          */
4577         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4578                 err = -EINVAL;
4579                 goto restore_opts;
4580         }
4581
4582         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4583                 ext4_abort(sb, "Abort forced by user");
4584
4585         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4586                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4587
4588         es = sbi->s_es;
4589
4590         if (sbi->s_journal) {
4591                 ext4_init_journal_params(sb, sbi->s_journal);
4592                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4593         }
4594
4595         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4596                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4597                         err = -EROFS;
4598                         goto restore_opts;
4599                 }
4600
4601                 if (*flags & MS_RDONLY) {
4602                         err = dquot_suspend(sb, -1);
4603                         if (err < 0)
4604                                 goto restore_opts;
4605
4606                         /*
4607                          * First of all, the unconditional stuff we have to do
4608                          * to disable replay of the journal when we next remount
4609                          */
4610                         sb->s_flags |= MS_RDONLY;
4611
4612                         /*
4613                          * OK, test if we are remounting a valid rw partition
4614                          * readonly, and if so set the rdonly flag and then
4615                          * mark the partition as valid again.
4616                          */
4617                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4618                             (sbi->s_mount_state & EXT4_VALID_FS))
4619                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4620
4621                         if (sbi->s_journal)
4622                                 ext4_mark_recovery_complete(sb, es);
4623                 } else {
4624                         /* Make sure we can mount this feature set readwrite */
4625                         if (!ext4_feature_set_ok(sb, 0)) {
4626                                 err = -EROFS;
4627                                 goto restore_opts;
4628                         }
4629                         /*
4630                          * Make sure the group descriptor checksums
4631                          * are sane.  If they aren't, refuse to remount r/w.
4632                          */
4633                         for (g = 0; g < sbi->s_groups_count; g++) {
4634                                 struct ext4_group_desc *gdp =
4635                                         ext4_get_group_desc(sb, g, NULL);
4636
4637                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
4638                                         ext4_msg(sb, KERN_ERR,
4639                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4640                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4641                                                le16_to_cpu(gdp->bg_checksum));
4642                                         err = -EINVAL;
4643                                         goto restore_opts;
4644                                 }
4645                         }
4646
4647                         /*
4648                          * If we have an unprocessed orphan list hanging
4649                          * around from a previously readonly bdev mount,
4650                          * require a full umount/remount for now.
4651                          */
4652                         if (es->s_last_orphan) {
4653                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4654                                        "remount RDWR because of unprocessed "
4655                                        "orphan inode list.  Please "
4656                                        "umount/remount instead");
4657                                 err = -EINVAL;
4658                                 goto restore_opts;
4659                         }
4660
4661                         /*
4662                          * Mounting a RDONLY partition read-write, so reread
4663                          * and store the current valid flag.  (It may have
4664                          * been changed by e2fsck since we originally mounted
4665                          * the partition.)
4666                          */
4667                         if (sbi->s_journal)
4668                                 ext4_clear_journal_err(sb, es);
4669                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4670                         if (!ext4_setup_super(sb, es, 0))
4671                                 sb->s_flags &= ~MS_RDONLY;
4672                         if (EXT4_HAS_INCOMPAT_FEATURE(sb,
4673                                                      EXT4_FEATURE_INCOMPAT_MMP))
4674                                 if (ext4_multi_mount_protect(sb,
4675                                                 le64_to_cpu(es->s_mmp_block))) {
4676                                         err = -EROFS;
4677                                         goto restore_opts;
4678                                 }
4679                         enable_quota = 1;
4680                 }
4681         }
4682
4683         /*
4684          * Reinitialize lazy itable initialization thread based on
4685          * current settings
4686          */
4687         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4688                 ext4_unregister_li_request(sb);
4689         else {
4690                 ext4_group_t first_not_zeroed;
4691                 first_not_zeroed = ext4_has_uninit_itable(sb);
4692                 ext4_register_li_request(sb, first_not_zeroed);
4693         }
4694
4695         ext4_setup_system_zone(sb);
4696         if (sbi->s_journal == NULL)
4697                 ext4_commit_super(sb, 1);
4698
4699         unlock_super(sb);
4700 #ifdef CONFIG_QUOTA
4701         /* Release old quota file names */
4702         for (i = 0; i < MAXQUOTAS; i++)
4703                 if (old_opts.s_qf_names[i] &&
4704                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4705                         kfree(old_opts.s_qf_names[i]);
4706         if (enable_quota) {
4707                 if (sb_any_quota_suspended(sb))
4708                         dquot_resume(sb, -1);
4709                 else if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
4710                                         EXT4_FEATURE_RO_COMPAT_QUOTA)) {
4711                         err = ext4_enable_quotas(sb);
4712                         if (err) {
4713                                 lock_super(sb);
4714                                 goto restore_opts;
4715                         }
4716                 }
4717         }
4718 #endif
4719
4720         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4721         kfree(orig_data);
4722         return 0;
4723
4724 restore_opts:
4725         sb->s_flags = old_sb_flags;
4726         sbi->s_mount_opt = old_opts.s_mount_opt;
4727         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4728         sbi->s_resuid = old_opts.s_resuid;
4729         sbi->s_resgid = old_opts.s_resgid;
4730         sbi->s_commit_interval = old_opts.s_commit_interval;
4731         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4732         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4733 #ifdef CONFIG_QUOTA
4734         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4735         for (i = 0; i < MAXQUOTAS; i++) {
4736                 if (sbi->s_qf_names[i] &&
4737                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4738                         kfree(sbi->s_qf_names[i]);
4739                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4740         }
4741 #endif
4742         unlock_super(sb);
4743         kfree(orig_data);
4744         return err;
4745 }
4746
4747 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4748 {
4749         struct super_block *sb = dentry->d_sb;
4750         struct ext4_sb_info *sbi = EXT4_SB(sb);
4751         struct ext4_super_block *es = sbi->s_es;
4752         ext4_fsblk_t overhead = 0;
4753         u64 fsid;
4754         s64 bfree;
4755
4756         if (!test_opt(sb, MINIX_DF))
4757                 overhead = sbi->s_overhead;
4758
4759         buf->f_type = EXT4_SUPER_MAGIC;
4760         buf->f_bsize = sb->s_blocksize;
4761         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, sbi->s_overhead);
4762         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
4763                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
4764         /* prevent underflow in case that few free space is available */
4765         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
4766         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
4767         if (buf->f_bfree < ext4_r_blocks_count(es))
4768                 buf->f_bavail = 0;
4769         buf->f_files = le32_to_cpu(es->s_inodes_count);
4770         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4771         buf->f_namelen = EXT4_NAME_LEN;
4772         fsid = le64_to_cpup((void *)es->s_uuid) ^
4773                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4774         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4775         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4776
4777         return 0;
4778 }
4779
4780 /* Helper function for writing quotas on sync - we need to start transaction
4781  * before quota file is locked for write. Otherwise the are possible deadlocks:
4782  * Process 1                         Process 2
4783  * ext4_create()                     quota_sync()
4784  *   jbd2_journal_start()                  write_dquot()
4785  *   dquot_initialize()                         down(dqio_mutex)
4786  *     down(dqio_mutex)                    jbd2_journal_start()
4787  *
4788  */
4789
4790 #ifdef CONFIG_QUOTA
4791
4792 static inline struct inode *dquot_to_inode(struct dquot *dquot)
4793 {
4794         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
4795 }
4796
4797 static int ext4_write_dquot(struct dquot *dquot)
4798 {
4799         int ret, err;
4800         handle_t *handle;
4801         struct inode *inode;
4802
4803         inode = dquot_to_inode(dquot);
4804         handle = ext4_journal_start(inode,
4805                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4806         if (IS_ERR(handle))
4807                 return PTR_ERR(handle);
4808         ret = dquot_commit(dquot);
4809         err = ext4_journal_stop(handle);
4810         if (!ret)
4811                 ret = err;
4812         return ret;
4813 }
4814
4815 static int ext4_acquire_dquot(struct dquot *dquot)
4816 {
4817         int ret, err;
4818         handle_t *handle;
4819
4820         handle = ext4_journal_start(dquot_to_inode(dquot),
4821                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4822         if (IS_ERR(handle))
4823                 return PTR_ERR(handle);
4824         ret = dquot_acquire(dquot);
4825         err = ext4_journal_stop(handle);
4826         if (!ret)
4827                 ret = err;
4828         return ret;
4829 }
4830
4831 static int ext4_release_dquot(struct dquot *dquot)
4832 {
4833         int ret, err;
4834         handle_t *handle;
4835
4836         handle = ext4_journal_start(dquot_to_inode(dquot),
4837                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4838         if (IS_ERR(handle)) {
4839                 /* Release dquot anyway to avoid endless cycle in dqput() */
4840                 dquot_release(dquot);
4841                 return PTR_ERR(handle);
4842         }
4843         ret = dquot_release(dquot);
4844         err = ext4_journal_stop(handle);
4845         if (!ret)
4846                 ret = err;
4847         return ret;
4848 }
4849
4850 static int ext4_mark_dquot_dirty(struct dquot *dquot)
4851 {
4852         /* Are we journaling quotas? */
4853         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
4854             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
4855                 dquot_mark_dquot_dirty(dquot);
4856                 return ext4_write_dquot(dquot);
4857         } else {
4858                 return dquot_mark_dquot_dirty(dquot);
4859         }
4860 }
4861
4862 static int ext4_write_info(struct super_block *sb, int type)
4863 {
4864         int ret, err;
4865         handle_t *handle;
4866
4867         /* Data block + inode block */
4868         handle = ext4_journal_start(sb->s_root->d_inode, 2);
4869         if (IS_ERR(handle))
4870                 return PTR_ERR(handle);
4871         ret = dquot_commit_info(sb, type);
4872         err = ext4_journal_stop(handle);
4873         if (!ret)
4874                 ret = err;
4875         return ret;
4876 }
4877
4878 /*
4879  * Turn on quotas during mount time - we need to find
4880  * the quota file and such...
4881  */
4882 static int ext4_quota_on_mount(struct super_block *sb, int type)
4883 {
4884         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4885                                         EXT4_SB(sb)->s_jquota_fmt, type);
4886 }
4887
4888 /*
4889  * Standard function to be called on quota_on
4890  */
4891 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4892                          struct path *path)
4893 {
4894         int err;
4895
4896         if (!test_opt(sb, QUOTA))
4897                 return -EINVAL;
4898
4899         /* Quotafile not on the same filesystem? */
4900         if (path->dentry->d_sb != sb)
4901                 return -EXDEV;
4902         /* Journaling quota? */
4903         if (EXT4_SB(sb)->s_qf_names[type]) {
4904                 /* Quotafile not in fs root? */
4905                 if (path->dentry->d_parent != sb->s_root)
4906                         ext4_msg(sb, KERN_WARNING,
4907                                 "Quota file not on filesystem root. "
4908                                 "Journaled quota will not work");
4909         }
4910
4911         /*
4912          * When we journal data on quota file, we have to flush journal to see
4913          * all updates to the file when we bypass pagecache...
4914          */
4915         if (EXT4_SB(sb)->s_journal &&
4916             ext4_should_journal_data(path->dentry->d_inode)) {
4917                 /*
4918                  * We don't need to lock updates but journal_flush() could
4919                  * otherwise be livelocked...
4920                  */
4921                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4922                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4923                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4924                 if (err)
4925                         return err;
4926         }
4927
4928         return dquot_quota_on(sb, type, format_id, path);
4929 }
4930
4931 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
4932                              unsigned int flags)
4933 {
4934         int err;
4935         struct inode *qf_inode;
4936         unsigned long qf_inums[MAXQUOTAS] = {
4937                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
4938                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
4939         };
4940
4941         BUG_ON(!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA));
4942
4943         if (!qf_inums[type])
4944                 return -EPERM;
4945
4946         qf_inode = ext4_iget(sb, qf_inums[type]);
4947         if (IS_ERR(qf_inode)) {
4948                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
4949                 return PTR_ERR(qf_inode);
4950         }
4951
4952         err = dquot_enable(qf_inode, type, format_id, flags);
4953         iput(qf_inode);
4954
4955         return err;
4956 }
4957
4958 /* Enable usage tracking for all quota types. */
4959 static int ext4_enable_quotas(struct super_block *sb)
4960 {
4961         int type, err = 0;
4962         unsigned long qf_inums[MAXQUOTAS] = {
4963                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
4964                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
4965         };
4966
4967         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
4968         for (type = 0; type < MAXQUOTAS; type++) {
4969                 if (qf_inums[type]) {
4970                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
4971                                                 DQUOT_USAGE_ENABLED);
4972                         if (err) {
4973                                 ext4_warning(sb,
4974                                         "Failed to enable quota (type=%d) "
4975                                         "tracking. Please run e2fsck to fix.",
4976                                         type);
4977                                 return err;
4978                         }
4979                 }
4980         }
4981         return 0;
4982 }
4983
4984 /*
4985  * quota_on function that is used when QUOTA feature is set.
4986  */
4987 static int ext4_quota_on_sysfile(struct super_block *sb, int type,
4988                                  int format_id)
4989 {
4990         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
4991                 return -EINVAL;
4992
4993         /*
4994          * USAGE was enabled at mount time. Only need to enable LIMITS now.
4995          */
4996         return ext4_quota_enable(sb, type, format_id, DQUOT_LIMITS_ENABLED);
4997 }
4998
4999 static int ext4_quota_off(struct super_block *sb, int type)
5000 {
5001         struct inode *inode = sb_dqopt(sb)->files[type];
5002         handle_t *handle;
5003
5004         /* Force all delayed allocation blocks to be allocated.
5005          * Caller already holds s_umount sem */
5006         if (test_opt(sb, DELALLOC))
5007                 sync_filesystem(sb);
5008
5009         if (!inode)
5010                 goto out;
5011
5012         /* Update modification times of quota files when userspace can
5013          * start looking at them */
5014         handle = ext4_journal_start(inode, 1);
5015         if (IS_ERR(handle))
5016                 goto out;
5017         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
5018         ext4_mark_inode_dirty(handle, inode);
5019         ext4_journal_stop(handle);
5020
5021 out:
5022         return dquot_quota_off(sb, type);
5023 }
5024
5025 /*
5026  * quota_off function that is used when QUOTA feature is set.
5027  */
5028 static int ext4_quota_off_sysfile(struct super_block *sb, int type)
5029 {
5030         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
5031                 return -EINVAL;
5032
5033         /* Disable only the limits. */
5034         return dquot_disable(sb, type, DQUOT_LIMITS_ENABLED);
5035 }
5036
5037 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5038  * acquiring the locks... As quota files are never truncated and quota code
5039  * itself serializes the operations (and no one else should touch the files)
5040  * we don't have to be afraid of races */
5041 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5042                                size_t len, loff_t off)
5043 {
5044         struct inode *inode = sb_dqopt(sb)->files[type];
5045         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5046         int err = 0;
5047         int offset = off & (sb->s_blocksize - 1);
5048         int tocopy;
5049         size_t toread;
5050         struct buffer_head *bh;
5051         loff_t i_size = i_size_read(inode);
5052
5053         if (off > i_size)
5054                 return 0;
5055         if (off+len > i_size)
5056                 len = i_size-off;
5057         toread = len;
5058         while (toread > 0) {
5059                 tocopy = sb->s_blocksize - offset < toread ?
5060                                 sb->s_blocksize - offset : toread;
5061                 bh = ext4_bread(NULL, inode, blk, 0, &err);
5062                 if (err)
5063                         return err;
5064                 if (!bh)        /* A hole? */
5065                         memset(data, 0, tocopy);
5066                 else
5067                         memcpy(data, bh->b_data+offset, tocopy);
5068                 brelse(bh);
5069                 offset = 0;
5070                 toread -= tocopy;
5071                 data += tocopy;
5072                 blk++;
5073         }
5074         return len;
5075 }
5076
5077 /* Write to quotafile (we know the transaction is already started and has
5078  * enough credits) */
5079 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5080                                 const char *data, size_t len, loff_t off)
5081 {
5082         struct inode *inode = sb_dqopt(sb)->files[type];
5083         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5084         int err = 0;
5085         int offset = off & (sb->s_blocksize - 1);
5086         struct buffer_head *bh;
5087         handle_t *handle = journal_current_handle();
5088
5089         if (EXT4_SB(sb)->s_journal && !handle) {
5090                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5091                         " cancelled because transaction is not started",
5092                         (unsigned long long)off, (unsigned long long)len);
5093                 return -EIO;
5094         }
5095         /*
5096          * Since we account only one data block in transaction credits,
5097          * then it is impossible to cross a block boundary.
5098          */
5099         if (sb->s_blocksize - offset < len) {
5100                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5101                         " cancelled because not block aligned",
5102                         (unsigned long long)off, (unsigned long long)len);
5103                 return -EIO;
5104         }
5105
5106         bh = ext4_bread(handle, inode, blk, 1, &err);
5107         if (!bh)
5108                 goto out;
5109         err = ext4_journal_get_write_access(handle, bh);
5110         if (err) {
5111                 brelse(bh);
5112                 goto out;
5113         }
5114         lock_buffer(bh);
5115         memcpy(bh->b_data+offset, data, len);
5116         flush_dcache_page(bh->b_page);
5117         unlock_buffer(bh);
5118         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5119         brelse(bh);
5120 out:
5121         if (err)
5122                 return err;
5123         if (inode->i_size < off + len) {
5124                 i_size_write(inode, off + len);
5125                 EXT4_I(inode)->i_disksize = inode->i_size;
5126                 ext4_mark_inode_dirty(handle, inode);
5127         }
5128         return len;
5129 }
5130
5131 #endif
5132
5133 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5134                        const char *dev_name, void *data)
5135 {
5136         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5137 }
5138
5139 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5140 static inline void register_as_ext2(void)
5141 {
5142         int err = register_filesystem(&ext2_fs_type);
5143         if (err)
5144                 printk(KERN_WARNING
5145                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5146 }
5147
5148 static inline void unregister_as_ext2(void)
5149 {
5150         unregister_filesystem(&ext2_fs_type);
5151 }
5152
5153 static inline int ext2_feature_set_ok(struct super_block *sb)
5154 {
5155         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
5156                 return 0;
5157         if (sb->s_flags & MS_RDONLY)
5158                 return 1;
5159         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
5160                 return 0;
5161         return 1;
5162 }
5163 MODULE_ALIAS("ext2");
5164 #else
5165 static inline void register_as_ext2(void) { }
5166 static inline void unregister_as_ext2(void) { }
5167 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5168 #endif
5169
5170 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5171 static inline void register_as_ext3(void)
5172 {
5173         int err = register_filesystem(&ext3_fs_type);
5174         if (err)
5175                 printk(KERN_WARNING
5176                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5177 }
5178
5179 static inline void unregister_as_ext3(void)
5180 {
5181         unregister_filesystem(&ext3_fs_type);
5182 }
5183
5184 static inline int ext3_feature_set_ok(struct super_block *sb)
5185 {
5186         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
5187                 return 0;
5188         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
5189                 return 0;
5190         if (sb->s_flags & MS_RDONLY)
5191                 return 1;
5192         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
5193                 return 0;
5194         return 1;
5195 }
5196 MODULE_ALIAS("ext3");
5197 #else
5198 static inline void register_as_ext3(void) { }
5199 static inline void unregister_as_ext3(void) { }
5200 static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
5201 #endif
5202
5203 static struct file_system_type ext4_fs_type = {
5204         .owner          = THIS_MODULE,
5205         .name           = "ext4",
5206         .mount          = ext4_mount,
5207         .kill_sb        = kill_block_super,
5208         .fs_flags       = FS_REQUIRES_DEV,
5209 };
5210
5211 static int __init ext4_init_feat_adverts(void)
5212 {
5213         struct ext4_features *ef;
5214         int ret = -ENOMEM;
5215
5216         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
5217         if (!ef)
5218                 goto out;
5219
5220         ef->f_kobj.kset = ext4_kset;
5221         init_completion(&ef->f_kobj_unregister);
5222         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
5223                                    "features");
5224         if (ret) {
5225                 kfree(ef);
5226                 goto out;
5227         }
5228
5229         ext4_feat = ef;
5230         ret = 0;
5231 out:
5232         return ret;
5233 }
5234
5235 static void ext4_exit_feat_adverts(void)
5236 {
5237         kobject_put(&ext4_feat->f_kobj);
5238         wait_for_completion(&ext4_feat->f_kobj_unregister);
5239         kfree(ext4_feat);
5240 }
5241
5242 /* Shared across all ext4 file systems */
5243 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5244 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5245
5246 static int __init ext4_init_fs(void)
5247 {
5248         int i, err;
5249
5250         ext4_li_info = NULL;
5251         mutex_init(&ext4_li_mtx);
5252
5253         ext4_check_flag_values();
5254
5255         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5256                 mutex_init(&ext4__aio_mutex[i]);
5257                 init_waitqueue_head(&ext4__ioend_wq[i]);
5258         }
5259
5260         err = ext4_init_pageio();
5261         if (err)
5262                 return err;
5263         err = ext4_init_system_zone();
5264         if (err)
5265                 goto out6;
5266         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
5267         if (!ext4_kset)
5268                 goto out5;
5269         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
5270
5271         err = ext4_init_feat_adverts();
5272         if (err)
5273                 goto out4;
5274
5275         err = ext4_init_mballoc();
5276         if (err)
5277                 goto out3;
5278
5279         err = ext4_init_xattr();
5280         if (err)
5281                 goto out2;
5282         err = init_inodecache();
5283         if (err)
5284                 goto out1;
5285         register_as_ext3();
5286         register_as_ext2();
5287         err = register_filesystem(&ext4_fs_type);
5288         if (err)
5289                 goto out;
5290
5291         return 0;
5292 out:
5293         unregister_as_ext2();
5294         unregister_as_ext3();
5295         destroy_inodecache();
5296 out1:
5297         ext4_exit_xattr();
5298 out2:
5299         ext4_exit_mballoc();
5300 out3:
5301         ext4_exit_feat_adverts();
5302 out4:
5303         if (ext4_proc_root)
5304                 remove_proc_entry("fs/ext4", NULL);
5305         kset_unregister(ext4_kset);
5306 out5:
5307         ext4_exit_system_zone();
5308 out6:
5309         ext4_exit_pageio();
5310         return err;
5311 }
5312
5313 static void __exit ext4_exit_fs(void)
5314 {
5315         ext4_destroy_lazyinit_thread();
5316         unregister_as_ext2();
5317         unregister_as_ext3();
5318         unregister_filesystem(&ext4_fs_type);
5319         destroy_inodecache();
5320         ext4_exit_xattr();
5321         ext4_exit_mballoc();
5322         ext4_exit_feat_adverts();
5323         remove_proc_entry("fs/ext4", NULL);
5324         kset_unregister(ext4_kset);
5325         ext4_exit_system_zone();
5326         ext4_exit_pageio();
5327 }
5328
5329 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5330 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5331 MODULE_LICENSE("GPL");
5332 module_init(ext4_init_fs)
5333 module_exit(ext4_exit_fs)