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  * The only special thing we need to do here is to make sure that all
 331  * journal_end calls result in the superblock being marked dirty, so
 332  * that sync() will call the filesystem's write_super callback if
 333  * appropriate.
 334  *
 335  * To avoid j_barrier hold in userspace when a user calls freeze(),
 336  * ext4 prevents a new handle from being started by s_frozen, which
 337  * is in an upper layer.
 338  */
 339 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 340 {
 341         journal_t *journal;
 342         handle_t  *handle;
 343
 344         trace_ext4_journal_start(sb, nblocks, _RET_IP_);
 345         if (sb->s_flags & MS_RDONLY)
 346                 return ERR_PTR(-EROFS);
 347
 348         journal = EXT4_SB(sb)->s_journal;
 349         handle = ext4_journal_current_handle();
 350
 351         /*
 352          * If a handle has been started, it should be allowed to
 353          * finish, otherwise deadlock could happen between freeze
 354          * and others(e.g. truncate) due to the restart of the
 355          * journal handle if the filesystem is forzen and active
 356          * handles are not stopped.
 357          */
 358         if (!handle)
 359                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
 360
 361         if (!journal)
 362                 return ext4_get_nojournal();
 363         /*
 364          * Special case here: if the journal has aborted behind our
 365          * backs (eg. EIO in the commit thread), then we still need to
 366          * take the FS itself readonly cleanly.
 367          */
 368         if (is_journal_aborted(journal)) {
 369                 ext4_abort(sb, "Detected aborted journal");
 370                 return ERR_PTR(-EROFS);
 371         }
 372         return jbd2_journal_start(journal, nblocks);
 373 }
 374
 375 /*
 376  * The only special thing we need to do here is to make sure that all
 377  * jbd2_journal_stop calls result in the superblock being marked dirty, so
 378  * that sync() will call the filesystem's write_super callback if
 379  * appropriate.
 380  */
 381 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
 382 {
 383         struct super_block *sb;
 384         int err;
 385         int rc;
 386
 387         if (!ext4_handle_valid(handle)) {
 388                 ext4_put_nojournal(handle);
 389                 return 0;
 390         }
 391         sb = handle->h_transaction->t_journal->j_private;
 392         err = handle->h_err;
 393         rc = jbd2_journal_stop(handle);
 394
 395         if (!err)
 396                 err = rc;
 397         if (err)
 398                 __ext4_std_error(sb, where, line, err);
 399         return err;
 400 }
 401
 402 void ext4_journal_abort_handle(const char *caller, unsigned int line,
 403                                const char *err_fn, struct buffer_head *bh,
 404                                handle_t *handle, int err)
 405 {
 406         char nbuf[16];
 407         const char *errstr = ext4_decode_error(NULL, err, nbuf);
 408
 409         BUG_ON(!ext4_handle_valid(handle));
 410
 411         if (bh)
 412                 BUFFER_TRACE(bh, "abort");
 413
 414         if (!handle->h_err)
 415                 handle->h_err = err;
 416
 417         if (is_handle_aborted(handle))
 418                 return;
 419
 420         printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n",
 421                caller, line, errstr, err_fn);
 422
 423         jbd2_journal_abort_handle(handle);
 424 }
 425
 426 static void __save_error_info(struct super_block *sb, const char *func,
 427                             unsigned int line)
 428 {
 429         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 430
 431         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 432         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 433         es->s_last_error_time = cpu_to_le32(get_seconds());
 434         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 435         es->s_last_error_line = cpu_to_le32(line);
 436         if (!es->s_first_error_time) {
 437                 es->s_first_error_time = es->s_last_error_time;
 438                 strncpy(es->s_first_error_func, func,
 439                         sizeof(es->s_first_error_func));
 440                 es->s_first_error_line = cpu_to_le32(line);
 441                 es->s_first_error_ino = es->s_last_error_ino;
 442                 es->s_first_error_block = es->s_last_error_block;
 443         }
 444         /*
 445          * Start the daily error reporting function if it hasn't been
 446          * started already
 447          */
 448         if (!es->s_error_count)
 449                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 450         es->s_error_count = cpu_to_le32(le32_to_cpu(es->s_error_count) + 1);
 451 }
 452
 453 static void save_error_info(struct super_block *sb, const char *func,
 454                             unsigned int line)
 455 {
 456         __save_error_info(sb, func, line);
 457         ext4_commit_super(sb, 1);
 458 }
 459
 460 /*
 461  * The del_gendisk() function uninitializes the disk-specific data
 462  * structures, including the bdi structure, without telling anyone
 463  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 464  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 465  * This is a kludge to prevent these oops until we can put in a proper
 466  * hook in del_gendisk() to inform the VFS and file system layers.
 467  */
 468 static int block_device_ejected(struct super_block *sb)
 469 {
 470         struct inode *bd_inode = sb->s_bdev->bd_inode;
 471         struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info;
 472
 473         return bdi->dev == NULL;
 474 }
 475
 476 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 477 {
 478         struct super_block              *sb = journal->j_private;
 479         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 480         int                             error = is_journal_aborted(journal);
 481         struct ext4_journal_cb_entry    *jce, *tmp;
 482
 483         spin_lock(&sbi->s_md_lock);
 484         list_for_each_entry_safe(jce, tmp, &txn->t_private_list, jce_list) {
 485                 list_del_init(&jce->jce_list);
 486                 spin_unlock(&sbi->s_md_lock);
 487                 jce->jce_func(sb, jce, error);
 488                 spin_lock(&sbi->s_md_lock);
 489         }
 490         spin_unlock(&sbi->s_md_lock);
 491 }
 492
 493 /* Deal with the reporting of failure conditions on a filesystem such as
 494  * inconsistencies detected or read IO failures.
 495  *
 496  * On ext2, we can store the error state of the filesystem in the
 497  * superblock.  That is not possible on ext4, because we may have other
 498  * write ordering constraints on the superblock which prevent us from
 499  * writing it out straight away; and given that the journal is about to
 500  * be aborted, we can't rely on the current, or future, transactions to
 501  * write out the superblock safely.
 502  *
 503  * We'll just use the jbd2_journal_abort() error code to record an error in
 504  * the journal instead.  On recovery, the journal will complain about
 505  * that error until we've noted it down and cleared it.
 506  */
 507
 508 static void ext4_handle_error(struct super_block *sb)
 509 {
 510         if (sb->s_flags & MS_RDONLY)
 511                 return;
 512
 513         if (!test_opt(sb, ERRORS_CONT)) {
 514                 journal_t *journal = EXT4_SB(sb)->s_journal;
 515
 516                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 517                 if (journal)
 518                         jbd2_journal_abort(journal, -EIO);
 519         }
 520         if (test_opt(sb, ERRORS_RO)) {
 521                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 522                 sb->s_flags |= MS_RDONLY;
 523         }
 524         if (test_opt(sb, ERRORS_PANIC))
 525                 panic("EXT4-fs (device %s): panic forced after error\n",
 526                         sb->s_id);
 527 }
 528
 529 void __ext4_error(struct super_block *sb, const char *function,
 530                   unsigned int line, const char *fmt, ...)
 531 {
 532         struct va_format vaf;
 533         va_list args;
 534
 535         va_start(args, fmt);
 536         vaf.fmt = fmt;
 537         vaf.va = &args;
 538         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 539                sb->s_id, function, line, current->comm, &vaf);
 540         va_end(args);
 541         save_error_info(sb, function, line);
 542
 543         ext4_handle_error(sb);
 544 }
 545
 546 void ext4_error_inode(struct inode *inode, const char *function,
 547                       unsigned int line, ext4_fsblk_t block,
 548                       const char *fmt, ...)
 549 {
 550         va_list args;
 551         struct va_format vaf;
 552         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 553
 554         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 555         es->s_last_error_block = cpu_to_le64(block);
 556         save_error_info(inode->i_sb, function, line);
 557         va_start(args, fmt);
 558         vaf.fmt = fmt;
 559         vaf.va = &args;
 560         if (block)
 561                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 562                        "inode #%lu: block %llu: comm %s: %pV\n",
 563                        inode->i_sb->s_id, function, line, inode->i_ino,
 564                        block, current->comm, &vaf);
 565         else
 566                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 567                        "inode #%lu: comm %s: %pV\n",
 568                        inode->i_sb->s_id, function, line, inode->i_ino,
 569                        current->comm, &vaf);
 570         va_end(args);
 571
 572         ext4_handle_error(inode->i_sb);
 573 }
 574
 575 void ext4_error_file(struct file *file, const char *function,
 576                      unsigned int line, ext4_fsblk_t block,
 577                      const char *fmt, ...)
 578 {
 579         va_list args;
 580         struct va_format vaf;
 581         struct ext4_super_block *es;
 582         struct inode *inode = file->f_dentry->d_inode;
 583         char pathname[80], *path;
 584
 585         es = EXT4_SB(inode->i_sb)->s_es;
 586         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 587         save_error_info(inode->i_sb, function, line);
 588         path = d_path(&(file->f_path), pathname, sizeof(pathname));
 589         if (IS_ERR(path))
 590                 path = "(unknown)";
 591         va_start(args, fmt);
 592         vaf.fmt = fmt;
 593         vaf.va = &args;
 594         if (block)
 595                 printk(KERN_CRIT
 596                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 597                        "block %llu: comm %s: path %s: %pV\n",
 598                        inode->i_sb->s_id, function, line, inode->i_ino,
 599                        block, current->comm, path, &vaf);
 600         else
 601                 printk(KERN_CRIT
 602                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 603                        "comm %s: path %s: %pV\n",
 604                        inode->i_sb->s_id, function, line, inode->i_ino,
 605                        current->comm, path, &vaf);
 606         va_end(args);
 607
 608         ext4_handle_error(inode->i_sb);
 609 }
 610
 611 static const char *ext4_decode_error(struct super_block *sb, int errno,
 612                                      char nbuf[16])
 613 {
 614         char *errstr = NULL;
 615
 616         switch (errno) {
 617         case -EIO:
 618                 errstr = "IO failure";
 619                 break;
 620         case -ENOMEM:
 621                 errstr = "Out of memory";
 622                 break;
 623         case -EROFS:
 624                 if (!sb || (EXT4_SB(sb)->s_journal &&
 625                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 626                         errstr = "Journal has aborted";
 627                 else
 628                         errstr = "Readonly filesystem";
 629                 break;
 630         default:
 631                 /* If the caller passed in an extra buffer for unknown
 632                  * errors, textualise them now.  Else we just return
 633                  * NULL. */
 634                 if (nbuf) {
 635                         /* Check for truncated error codes... */
 636                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 637                                 errstr = nbuf;
 638                 }
 639                 break;
 640         }
 641
 642         return errstr;
 643 }
 644
 645 /* __ext4_std_error decodes expected errors from journaling functions
 646  * automatically and invokes the appropriate error response.  */
 647
 648 void __ext4_std_error(struct super_block *sb, const char *function,
 649                       unsigned int line, int errno)
 650 {
 651         char nbuf[16];
 652         const char *errstr;
 653
 654         /* Special case: if the error is EROFS, and we're not already
 655          * inside a transaction, then there's really no point in logging
 656          * an error. */
 657         if (errno == -EROFS && journal_current_handle() == NULL &&
 658             (sb->s_flags & MS_RDONLY))
 659                 return;
 660
 661         errstr = ext4_decode_error(sb, errno, nbuf);
 662         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 663                sb->s_id, function, line, errstr);
 664         save_error_info(sb, function, line);
 665
 666         ext4_handle_error(sb);
 667 }
 668
 669 /*
 670  * ext4_abort is a much stronger failure handler than ext4_error.  The
 671  * abort function may be used to deal with unrecoverable failures such
 672  * as journal IO errors or ENOMEM at a critical moment in log management.
 673  *
 674  * We unconditionally force the filesystem into an ABORT|READONLY state,
 675  * unless the error response on the fs has been set to panic in which
 676  * case we take the easy way out and panic immediately.
 677  */
 678
 679 void __ext4_abort(struct super_block *sb, const char *function,
 680                 unsigned int line, const char *fmt, ...)
 681 {
 682         va_list args;
 683
 684         save_error_info(sb, function, line);
 685         va_start(args, fmt);
 686         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 687                function, line);
 688         vprintk(fmt, args);
 689         printk("\n");
 690         va_end(args);
 691
 692         if ((sb->s_flags & MS_RDONLY) == 0) {
 693                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 694                 sb->s_flags |= MS_RDONLY;
 695                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 696                 if (EXT4_SB(sb)->s_journal)
 697                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 698                 save_error_info(sb, function, line);
 699         }
 700         if (test_opt(sb, ERRORS_PANIC))
 701                 panic("EXT4-fs panic from previous error\n");
 702 }
 703
 704 void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
 705 {
 706         struct va_format vaf;
 707         va_list args;
 708
 709         va_start(args, fmt);
 710         vaf.fmt = fmt;
 711         vaf.va = &args;
 712         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 713         va_end(args);
 714 }
 715
 716 void __ext4_warning(struct super_block *sb, const char *function,
 717                     unsigned int line, const char *fmt, ...)
 718 {
 719         struct va_format vaf;
 720         va_list args;
 721
 722         va_start(args, fmt);
 723         vaf.fmt = fmt;
 724         vaf.va = &args;
 725         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 726                sb->s_id, function, line, &vaf);
 727         va_end(args);
 728 }
 729
 730 void __ext4_grp_locked_error(const char *function, unsigned int line,
 731                              struct super_block *sb, ext4_group_t grp,
 732                              unsigned long ino, ext4_fsblk_t block,
 733                              const char *fmt, ...)
 734 __releases(bitlock)
 735 __acquires(bitlock)
 736 {
 737         struct va_format vaf;
 738         va_list args;
 739         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 740
 741         es->s_last_error_ino = cpu_to_le32(ino);
 742         es->s_last_error_block = cpu_to_le64(block);
 743         __save_error_info(sb, function, line);
 744
 745         va_start(args, fmt);
 746
 747         vaf.fmt = fmt;
 748         vaf.va = &args;
 749         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 750                sb->s_id, function, line, grp);
 751         if (ino)
 752                 printk(KERN_CONT "inode %lu: ", ino);
 753         if (block)
 754                 printk(KERN_CONT "block %llu:", (unsigned long long) block);
 755         printk(KERN_CONT "%pV\n", &vaf);
 756         va_end(args);
 757
 758         if (test_opt(sb, ERRORS_CONT)) {
 759                 ext4_commit_super(sb, 0);
 760                 return;
 761         }
 762
 763         ext4_unlock_group(sb, grp);
 764         ext4_handle_error(sb);
 765         /*
 766          * We only get here in the ERRORS_RO case; relocking the group
 767          * may be dangerous, but nothing bad will happen since the
 768          * filesystem will have already been marked read/only and the
 769          * journal has been aborted.  We return 1 as a hint to callers
 770          * who might what to use the return value from
 771          * ext4_grp_locked_error() to distinguish between the
 772          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 773          * aggressively from the ext4 function in question, with a
 774          * more appropriate error code.
 775          */
 776         ext4_lock_group(sb, grp);
 777         return;
 778 }
 779
 780 void ext4_update_dynamic_rev(struct super_block *sb)
 781 {
 782         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 783
 784         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 785                 return;
 786
 787         ext4_warning(sb,
 788                      "updating to rev %d because of new feature flag, "
 789                      "running e2fsck is recommended",
 790                      EXT4_DYNAMIC_REV);
 791
 792         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 793         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 794         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 795         /* leave es->s_feature_*compat flags alone */
 796         /* es->s_uuid will be set by e2fsck if empty */
 797
 798         /*
 799          * The rest of the superblock fields should be zero, and if not it
 800          * means they are likely already in use, so leave them alone.  We
 801          * can leave it up to e2fsck to clean up any inconsistencies there.
 802          */
 803 }
 804
 805 /*
 806  * Open the external journal device
 807  */
 808 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 809 {
 810         struct block_device *bdev;
 811         char b[BDEVNAME_SIZE];
 812
 813         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 814         if (IS_ERR(bdev))
 815                 goto fail;
 816         return bdev;
 817
 818 fail:
 819         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 820                         __bdevname(dev, b), PTR_ERR(bdev));
 821         return NULL;
 822 }
 823
 824 /*
 825  * Release the journal device
 826  */
 827 static int ext4_blkdev_put(struct block_device *bdev)
 828 {
 829         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 830 }
 831
 832 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
 833 {
 834         struct block_device *bdev;
 835         int ret = -ENODEV;
 836
 837         bdev = sbi->journal_bdev;
 838         if (bdev) {
 839                 ret = ext4_blkdev_put(bdev);
 840                 sbi->journal_bdev = NULL;
 841         }
 842         return ret;
 843 }
 844
 845 static inline struct inode *orphan_list_entry(struct list_head *l)
 846 {
 847         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 848 }
 849
 850 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 851 {
 852         struct list_head *l;
 853
 854         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 855                  le32_to_cpu(sbi->s_es->s_last_orphan));
 856
 857         printk(KERN_ERR "sb_info orphan list:\n");
 858         list_for_each(l, &sbi->s_orphan) {
 859                 struct inode *inode = orphan_list_entry(l);
 860                 printk(KERN_ERR "  "
 861                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 862                        inode->i_sb->s_id, inode->i_ino, inode,
 863                        inode->i_mode, inode->i_nlink,
 864                        NEXT_ORPHAN(inode));
 865         }
 866 }
 867
 868 static void ext4_put_super(struct super_block *sb)
 869 {
 870         struct ext4_sb_info *sbi = EXT4_SB(sb);
 871         struct ext4_super_block *es = sbi->s_es;
 872         int i, err;
 873
 874         ext4_unregister_li_request(sb);
 875         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 876
 877         flush_workqueue(sbi->dio_unwritten_wq);
 878         destroy_workqueue(sbi->dio_unwritten_wq);
 879
 880         lock_super(sb);
 881         if (sbi->s_journal) {
 882                 err = jbd2_journal_destroy(sbi->s_journal);
 883                 sbi->s_journal = NULL;
 884                 if (err < 0)
 885                         ext4_abort(sb, "Couldn't clean up the journal");
 886         }
 887
 888         del_timer(&sbi->s_err_report);
 889         ext4_release_system_zone(sb);
 890         ext4_mb_release(sb);
 891         ext4_ext_release(sb);
 892         ext4_xattr_put_super(sb);
 893
 894         if (!(sb->s_flags & MS_RDONLY)) {
 895                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 896                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 897         }
 898         if (!(sb->s_flags & MS_RDONLY))
 899                 ext4_commit_super(sb, 1);
 900
 901         if (sbi->s_proc) {
 902                 remove_proc_entry("options", sbi->s_proc);
 903                 remove_proc_entry(sb->s_id, ext4_proc_root);
 904         }
 905         kobject_del(&sbi->s_kobj);
 906
 907         for (i = 0; i < sbi->s_gdb_count; i++)
 908                 brelse(sbi->s_group_desc[i]);
 909         ext4_kvfree(sbi->s_group_desc);
 910         ext4_kvfree(sbi->s_flex_groups);
 911         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 912         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 913         percpu_counter_destroy(&sbi->s_dirs_counter);
 914         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 915         brelse(sbi->s_sbh);
 916 #ifdef CONFIG_QUOTA
 917         for (i = 0; i < MAXQUOTAS; i++)
 918                 kfree(sbi->s_qf_names[i]);
 919 #endif
 920
 921         /* Debugging code just in case the in-memory inode orphan list
 922          * isn't empty.  The on-disk one can be non-empty if we've
 923          * detected an error and taken the fs readonly, but the
 924          * in-memory list had better be clean by this point. */
 925         if (!list_empty(&sbi->s_orphan))
 926                 dump_orphan_list(sb, sbi);
 927         J_ASSERT(list_empty(&sbi->s_orphan));
 928
 929         invalidate_bdev(sb->s_bdev);
 930         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 931                 /*
 932                  * Invalidate the journal device's buffers.  We don't want them
 933                  * floating about in memory - the physical journal device may
 934                  * hotswapped, and it breaks the `ro-after' testing code.
 935                  */
 936                 sync_blockdev(sbi->journal_bdev);
 937                 invalidate_bdev(sbi->journal_bdev);
 938                 ext4_blkdev_remove(sbi);
 939         }
 940         if (sbi->s_mmp_tsk)
 941                 kthread_stop(sbi->s_mmp_tsk);
 942         sb->s_fs_info = NULL;
 943         /*
 944          * Now that we are completely done shutting down the
 945          * superblock, we need to actually destroy the kobject.
 946          */
 947         unlock_super(sb);
 948         kobject_put(&sbi->s_kobj);
 949         wait_for_completion(&sbi->s_kobj_unregister);
 950         if (sbi->s_chksum_driver)
 951                 crypto_free_shash(sbi->s_chksum_driver);
 952         kfree(sbi->s_blockgroup_lock);
 953         kfree(sbi);
 954 }
 955
 956 static struct kmem_cache *ext4_inode_cachep;
 957
 958 /*
 959  * Called inside transaction, so use GFP_NOFS
 960  */
 961 static struct inode *ext4_alloc_inode(struct super_block *sb)
 962 {
 963         struct ext4_inode_info *ei;
 964
 965         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 966         if (!ei)
 967                 return NULL;
 968
 969         ei->vfs_inode.i_version = 1;
 970         ei->vfs_inode.i_data.writeback_index = 0;
 971         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
 972         INIT_LIST_HEAD(&ei->i_prealloc_list);
 973         spin_lock_init(&ei->i_prealloc_lock);
 974         ei->i_reserved_data_blocks = 0;
 975         ei->i_reserved_meta_blocks = 0;
 976         ei->i_allocated_meta_blocks = 0;
 977         ei->i_da_metadata_calc_len = 0;
 978         spin_lock_init(&(ei->i_block_reservation_lock));
 979 #ifdef CONFIG_QUOTA
 980         ei->i_reserved_quota = 0;
 981 #endif
 982         ei->jinode = NULL;
 983         INIT_LIST_HEAD(&ei->i_completed_io_list);
 984         spin_lock_init(&ei->i_completed_io_lock);
 985         ei->cur_aio_dio = NULL;
 986         ei->i_sync_tid = 0;
 987         ei->i_datasync_tid = 0;
 988         atomic_set(&ei->i_ioend_count, 0);
 989         atomic_set(&ei->i_aiodio_unwritten, 0);
 990
 991         return &ei->vfs_inode;
 992 }
 993
 994 static int ext4_drop_inode(struct inode *inode)
 995 {
 996         int drop = generic_drop_inode(inode);
 997
 998         trace_ext4_drop_inode(inode, drop);
 999         return drop;
1000 }
1001
1002 static void ext4_i_callback(struct rcu_head *head)
1003 {
1004         struct inode *inode = container_of(head, struct inode, i_rcu);
1005         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1006 }
1007
1008 static void ext4_destroy_inode(struct inode *inode)
1009 {
1010         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1011                 ext4_msg(inode->i_sb, KERN_ERR,
1012                          "Inode %lu (%p): orphan list check failed!",
1013                          inode->i_ino, EXT4_I(inode));
1014                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1015                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1016                                 true);
1017                 dump_stack();
1018         }
1019         call_rcu(&inode->i_rcu, ext4_i_callback);
1020 }
1021
1022 static void init_once(void *foo)
1023 {
1024         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1025
1026         INIT_LIST_HEAD(&ei->i_orphan);
1027 #ifdef CONFIG_EXT4_FS_XATTR
1028         init_rwsem(&ei->xattr_sem);
1029 #endif
1030         init_rwsem(&ei->i_data_sem);
1031         inode_init_once(&ei->vfs_inode);
1032 }
1033
1034 static int init_inodecache(void)
1035 {
1036         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
1037                                              sizeof(struct ext4_inode_info),
1038                                              0, (SLAB_RECLAIM_ACCOUNT|
1039                                                 SLAB_MEM_SPREAD),
1040                                              init_once);
1041         if (ext4_inode_cachep == NULL)
1042                 return -ENOMEM;
1043         return 0;
1044 }
1045
1046 static void destroy_inodecache(void)
1047 {
1048         kmem_cache_destroy(ext4_inode_cachep);
1049 }
1050
1051 void ext4_clear_inode(struct inode *inode)
1052 {
1053         invalidate_inode_buffers(inode);
1054         clear_inode(inode);
1055         dquot_drop(inode);
1056         ext4_discard_preallocations(inode);
1057         if (EXT4_I(inode)->jinode) {
1058                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1059                                                EXT4_I(inode)->jinode);
1060                 jbd2_free_inode(EXT4_I(inode)->jinode);
1061                 EXT4_I(inode)->jinode = NULL;
1062         }
1063 }
1064
1065 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1066                                         u64 ino, u32 generation)
1067 {
1068         struct inode *inode;
1069
1070         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1071                 return ERR_PTR(-ESTALE);
1072         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1073                 return ERR_PTR(-ESTALE);
1074
1075         /* iget isn't really right if the inode is currently unallocated!!
1076          *
1077          * ext4_read_inode will return a bad_inode if the inode had been
1078          * deleted, so we should be safe.
1079          *
1080          * Currently we don't know the generation for parent directory, so
1081          * a generation of 0 means "accept any"
1082          */
1083         inode = ext4_iget(sb, ino);
1084         if (IS_ERR(inode))
1085                 return ERR_CAST(inode);
1086         if (generation && inode->i_generation != generation) {
1087                 iput(inode);
1088                 return ERR_PTR(-ESTALE);
1089         }
1090
1091         return inode;
1092 }
1093
1094 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1095                                         int fh_len, int fh_type)
1096 {
1097         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1098                                     ext4_nfs_get_inode);
1099 }
1100
1101 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1102                                         int fh_len, int fh_type)
1103 {
1104         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1105                                     ext4_nfs_get_inode);
1106 }
1107
1108 /*
1109  * Try to release metadata pages (indirect blocks, directories) which are
1110  * mapped via the block device.  Since these pages could have journal heads
1111  * which would prevent try_to_free_buffers() from freeing them, we must use
1112  * jbd2 layer's try_to_free_buffers() function to release them.
1113  */
1114 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1115                                  gfp_t wait)
1116 {
1117         journal_t *journal = EXT4_SB(sb)->s_journal;
1118
1119         WARN_ON(PageChecked(page));
1120         if (!page_has_buffers(page))
1121                 return 0;
1122         if (journal)
1123                 return jbd2_journal_try_to_free_buffers(journal, page,
1124                                                         wait & ~__GFP_WAIT);
1125         return try_to_free_buffers(page);
1126 }
1127
1128 #ifdef CONFIG_QUOTA
1129 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1130 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1131
1132 static int ext4_write_dquot(struct dquot *dquot);
1133 static int ext4_acquire_dquot(struct dquot *dquot);
1134 static int ext4_release_dquot(struct dquot *dquot);
1135 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1136 static int ext4_write_info(struct super_block *sb, int type);
1137 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1138                          struct path *path);
1139 static int ext4_quota_on_sysfile(struct super_block *sb, int type,
1140                                  int format_id);
1141 static int ext4_quota_off(struct super_block *sb, int type);
1142 static int ext4_quota_off_sysfile(struct super_block *sb, int type);
1143 static int ext4_quota_on_mount(struct super_block *sb, int type);
1144 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1145                                size_t len, loff_t off);
1146 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1147                                 const char *data, size_t len, loff_t off);
1148 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1149                              unsigned int flags);
1150 static int ext4_enable_quotas(struct super_block *sb);
1151
1152 static const struct dquot_operations ext4_quota_operations = {
1153         .get_reserved_space = ext4_get_reserved_space,
1154         .write_dquot    = ext4_write_dquot,
1155         .acquire_dquot  = ext4_acquire_dquot,
1156         .release_dquot  = ext4_release_dquot,
1157         .mark_dirty     = ext4_mark_dquot_dirty,
1158         .write_info     = ext4_write_info,
1159         .alloc_dquot    = dquot_alloc,
1160         .destroy_dquot  = dquot_destroy,
1161 };
1162
1163 static const struct quotactl_ops ext4_qctl_operations = {
1164         .quota_on       = ext4_quota_on,
1165         .quota_off      = ext4_quota_off,
1166         .quota_sync     = dquot_quota_sync,
1167         .get_info       = dquot_get_dqinfo,
1168         .set_info       = dquot_set_dqinfo,
1169         .get_dqblk      = dquot_get_dqblk,
1170         .set_dqblk      = dquot_set_dqblk
1171 };
1172
1173 static const struct quotactl_ops ext4_qctl_sysfile_operations = {
1174         .quota_on_meta  = ext4_quota_on_sysfile,
1175         .quota_off      = ext4_quota_off_sysfile,
1176         .quota_sync     = dquot_quota_sync,
1177         .get_info       = dquot_get_dqinfo,
1178         .set_info       = dquot_set_dqinfo,
1179         .get_dqblk      = dquot_get_dqblk,
1180         .set_dqblk      = dquot_set_dqblk
1181 };
1182 #endif
1183
1184 static const struct super_operations ext4_sops = {
1185         .alloc_inode    = ext4_alloc_inode,
1186         .destroy_inode  = ext4_destroy_inode,
1187         .write_inode    = ext4_write_inode,
1188         .dirty_inode    = ext4_dirty_inode,
1189         .drop_inode     = ext4_drop_inode,
1190         .evict_inode    = ext4_evict_inode,
1191         .put_super      = ext4_put_super,
1192         .sync_fs        = ext4_sync_fs,
1193         .freeze_fs      = ext4_freeze,
1194         .unfreeze_fs    = ext4_unfreeze,
1195         .statfs         = ext4_statfs,
1196         .remount_fs     = ext4_remount,
1197         .show_options   = ext4_show_options,
1198 #ifdef CONFIG_QUOTA
1199         .quota_read     = ext4_quota_read,
1200         .quota_write    = ext4_quota_write,
1201 #endif
1202         .bdev_try_to_free_page = bdev_try_to_free_page,
1203 };
1204
1205 static const struct super_operations ext4_nojournal_sops = {
1206         .alloc_inode    = ext4_alloc_inode,
1207         .destroy_inode  = ext4_destroy_inode,
1208         .write_inode    = ext4_write_inode,
1209         .dirty_inode    = ext4_dirty_inode,
1210         .drop_inode     = ext4_drop_inode,
1211         .evict_inode    = ext4_evict_inode,
1212         .put_super      = ext4_put_super,
1213         .statfs         = ext4_statfs,
1214         .remount_fs     = ext4_remount,
1215         .show_options   = ext4_show_options,
1216 #ifdef CONFIG_QUOTA
1217         .quota_read     = ext4_quota_read,
1218         .quota_write    = ext4_quota_write,
1219 #endif
1220         .bdev_try_to_free_page = bdev_try_to_free_page,
1221 };
1222
1223 static const struct export_operations ext4_export_ops = {
1224         .fh_to_dentry = ext4_fh_to_dentry,
1225         .fh_to_parent = ext4_fh_to_parent,
1226         .get_parent = ext4_get_parent,
1227 };
1228
1229 enum {
1230         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1231         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1232         Opt_nouid32, Opt_debug, Opt_removed,
1233         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1234         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1235         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1236         Opt_journal_dev, Opt_journal_checksum, Opt_journal_async_commit,
1237         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1238         Opt_data_err_abort, Opt_data_err_ignore,
1239         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1240         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1241         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1242         Opt_usrquota, Opt_grpquota, Opt_i_version,
1243         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1244         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1245         Opt_inode_readahead_blks, Opt_journal_ioprio,
1246         Opt_dioread_nolock, Opt_dioread_lock,
1247         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1248 };
1249
1250 static const match_table_t tokens = {
1251         {Opt_bsd_df, "bsddf"},
1252         {Opt_minix_df, "minixdf"},
1253         {Opt_grpid, "grpid"},
1254         {Opt_grpid, "bsdgroups"},
1255         {Opt_nogrpid, "nogrpid"},
1256         {Opt_nogrpid, "sysvgroups"},
1257         {Opt_resgid, "resgid=%u"},
1258         {Opt_resuid, "resuid=%u"},
1259         {Opt_sb, "sb=%u"},
1260         {Opt_err_cont, "errors=continue"},
1261         {Opt_err_panic, "errors=panic"},
1262         {Opt_err_ro, "errors=remount-ro"},
1263         {Opt_nouid32, "nouid32"},
1264         {Opt_debug, "debug"},
1265         {Opt_removed, "oldalloc"},
1266         {Opt_removed, "orlov"},
1267         {Opt_user_xattr, "user_xattr"},
1268         {Opt_nouser_xattr, "nouser_xattr"},
1269         {Opt_acl, "acl"},
1270         {Opt_noacl, "noacl"},
1271         {Opt_noload, "norecovery"},
1272         {Opt_noload, "noload"},
1273         {Opt_removed, "nobh"},
1274         {Opt_removed, "bh"},
1275         {Opt_commit, "commit=%u"},
1276         {Opt_min_batch_time, "min_batch_time=%u"},
1277         {Opt_max_batch_time, "max_batch_time=%u"},
1278         {Opt_journal_dev, "journal_dev=%u"},
1279         {Opt_journal_checksum, "journal_checksum"},
1280         {Opt_journal_async_commit, "journal_async_commit"},
1281         {Opt_abort, "abort"},
1282         {Opt_data_journal, "data=journal"},
1283         {Opt_data_ordered, "data=ordered"},
1284         {Opt_data_writeback, "data=writeback"},
1285         {Opt_data_err_abort, "data_err=abort"},
1286         {Opt_data_err_ignore, "data_err=ignore"},
1287         {Opt_offusrjquota, "usrjquota="},
1288         {Opt_usrjquota, "usrjquota=%s"},
1289         {Opt_offgrpjquota, "grpjquota="},
1290         {Opt_grpjquota, "grpjquota=%s"},
1291         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1292         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1293         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1294         {Opt_grpquota, "grpquota"},
1295         {Opt_noquota, "noquota"},
1296         {Opt_quota, "quota"},
1297         {Opt_usrquota, "usrquota"},
1298         {Opt_barrier, "barrier=%u"},
1299         {Opt_barrier, "barrier"},
1300         {Opt_nobarrier, "nobarrier"},
1301         {Opt_i_version, "i_version"},
1302         {Opt_stripe, "stripe=%u"},
1303         {Opt_delalloc, "delalloc"},
1304         {Opt_nodelalloc, "nodelalloc"},
1305         {Opt_mblk_io_submit, "mblk_io_submit"},
1306         {Opt_nomblk_io_submit, "nomblk_io_submit"},
1307         {Opt_block_validity, "block_validity"},
1308         {Opt_noblock_validity, "noblock_validity"},
1309         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1310         {Opt_journal_ioprio, "journal_ioprio=%u"},
1311         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1312         {Opt_auto_da_alloc, "auto_da_alloc"},
1313         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1314         {Opt_dioread_nolock, "dioread_nolock"},
1315         {Opt_dioread_lock, "dioread_lock"},
1316         {Opt_discard, "discard"},
1317         {Opt_nodiscard, "nodiscard"},
1318         {Opt_init_itable, "init_itable=%u"},
1319         {Opt_init_itable, "init_itable"},
1320         {Opt_noinit_itable, "noinit_itable"},
1321         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1322         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1323         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1324         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1325         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1326         {Opt_err, NULL},
1327 };
1328
1329 static ext4_fsblk_t get_sb_block(void **data)
1330 {
1331         ext4_fsblk_t    sb_block;
1332         char            *options = (char *) *data;
1333
1334         if (!options || strncmp(options, "sb=", 3) != 0)
1335                 return 1;       /* Default location */
1336
1337         options += 3;
1338         /* TODO: use simple_strtoll with >32bit ext4 */
1339         sb_block = simple_strtoul(options, &options, 0);
1340         if (*options && *options != ',') {
1341                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1342                        (char *) *data);
1343                 return 1;
1344         }
1345         if (*options == ',')
1346                 options++;
1347         *data = (void *) options;
1348
1349         return sb_block;
1350 }
1351
1352 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1353 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1354         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1355
1356 #ifdef CONFIG_QUOTA
1357 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1358 {
1359         struct ext4_sb_info *sbi = EXT4_SB(sb);
1360         char *qname;
1361
1362         if (sb_any_quota_loaded(sb) &&
1363                 !sbi->s_qf_names[qtype]) {
1364                 ext4_msg(sb, KERN_ERR,
1365                         "Cannot change journaled "
1366                         "quota options when quota turned on");
1367                 return -1;
1368         }
1369         qname = match_strdup(args);
1370         if (!qname) {
1371                 ext4_msg(sb, KERN_ERR,
1372                         "Not enough memory for storing quotafile name");
1373                 return -1;
1374         }
1375         if (sbi->s_qf_names[qtype] &&
1376                 strcmp(sbi->s_qf_names[qtype], qname)) {
1377                 ext4_msg(sb, KERN_ERR,
1378                         "%s quota file already specified", QTYPE2NAME(qtype));
1379                 kfree(qname);
1380                 return -1;
1381         }
1382         sbi->s_qf_names[qtype] = qname;
1383         if (strchr(sbi->s_qf_names[qtype], '/')) {
1384                 ext4_msg(sb, KERN_ERR,
1385                         "quotafile must be on filesystem root");
1386                 kfree(sbi->s_qf_names[qtype]);
1387                 sbi->s_qf_names[qtype] = NULL;
1388                 return -1;
1389         }
1390         set_opt(sb, QUOTA);
1391         return 1;
1392 }
1393
1394 static int clear_qf_name(struct super_block *sb, int qtype)
1395 {
1396
1397         struct ext4_sb_info *sbi = EXT4_SB(sb);
1398
1399         if (sb_any_quota_loaded(sb) &&
1400                 sbi->s_qf_names[qtype]) {
1401                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1402                         " when quota turned on");
1403                 return -1;
1404         }
1405         /*
1406          * The space will be released later when all options are confirmed
1407          * to be correct
1408          */
1409         sbi->s_qf_names[qtype] = NULL;
1410         return 1;
1411 }
1412 #endif
1413
1414 #define MOPT_SET        0x0001
1415 #define MOPT_CLEAR      0x0002
1416 #define MOPT_NOSUPPORT  0x0004
1417 #define MOPT_EXPLICIT   0x0008
1418 #define MOPT_CLEAR_ERR  0x0010
1419 #define MOPT_GTE0       0x0020
1420 #ifdef CONFIG_QUOTA
1421 #define MOPT_Q          0
1422 #define MOPT_QFMT       0x0040
1423 #else
1424 #define MOPT_Q          MOPT_NOSUPPORT
1425 #define MOPT_QFMT       MOPT_NOSUPPORT
1426 #endif
1427 #define MOPT_DATAJ      0x0080
1428
1429 static const struct mount_opts {
1430         int     token;
1431         int     mount_opt;
1432         int     flags;
1433 } ext4_mount_opts[] = {
1434         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1435         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1436         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1437         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1438         {Opt_mblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_SET},
1439         {Opt_nomblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_CLEAR},
1440         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1441         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1442         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_SET},
1443         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_CLEAR},
1444         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1445         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1446         {Opt_delalloc, EXT4_MOUNT_DELALLOC, MOPT_SET | MOPT_EXPLICIT},
1447         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC, MOPT_CLEAR | MOPT_EXPLICIT},
1448         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM, MOPT_SET},
1449         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1450                                     EXT4_MOUNT_JOURNAL_CHECKSUM), MOPT_SET},
1451         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_SET},
1452         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1453         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1454         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1455         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_SET},
1456         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_CLEAR},
1457         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1458         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1459         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1460         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1461         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1462         {Opt_commit, 0, MOPT_GTE0},
1463         {Opt_max_batch_time, 0, MOPT_GTE0},
1464         {Opt_min_batch_time, 0, MOPT_GTE0},
1465         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1466         {Opt_init_itable, 0, MOPT_GTE0},
1467         {Opt_stripe, 0, MOPT_GTE0},
1468         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_DATAJ},
1469         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_DATAJ},
1470         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA, MOPT_DATAJ},
1471 #ifdef CONFIG_EXT4_FS_XATTR
1472         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1473         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1474 #else
1475         {Opt_user_xattr, 0, MOPT_NOSUPPORT},
1476         {Opt_nouser_xattr, 0, MOPT_NOSUPPORT},
1477 #endif
1478 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1479         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1480         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1481 #else
1482         {Opt_acl, 0, MOPT_NOSUPPORT},
1483         {Opt_noacl, 0, MOPT_NOSUPPORT},
1484 #endif
1485         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1486         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1487         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1488         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1489                                                         MOPT_SET | MOPT_Q},
1490         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1491                                                         MOPT_SET | MOPT_Q},
1492         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1493                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1494         {Opt_usrjquota, 0, MOPT_Q},
1495         {Opt_grpjquota, 0, MOPT_Q},
1496         {Opt_offusrjquota, 0, MOPT_Q},
1497         {Opt_offgrpjquota, 0, MOPT_Q},
1498         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1499         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1500         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1501         {Opt_err, 0, 0}
1502 };
1503
1504 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1505                             substring_t *args, unsigned long *journal_devnum,
1506                             unsigned int *journal_ioprio, int is_remount)
1507 {
1508         struct ext4_sb_info *sbi = EXT4_SB(sb);
1509         const struct mount_opts *m;
1510         kuid_t uid;
1511         kgid_t gid;
1512         int arg = 0;
1513
1514 #ifdef CONFIG_QUOTA
1515         if (token == Opt_usrjquota)
1516                 return set_qf_name(sb, USRQUOTA, &args[0]);
1517         else if (token == Opt_grpjquota)
1518                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1519         else if (token == Opt_offusrjquota)
1520                 return clear_qf_name(sb, USRQUOTA);
1521         else if (token == Opt_offgrpjquota)
1522                 return clear_qf_name(sb, GRPQUOTA);
1523 #endif
1524         if (args->from && match_int(args, &arg))
1525                 return -1;
1526         switch (token) {
1527         case Opt_noacl:
1528         case Opt_nouser_xattr:
1529                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1530                 break;
1531         case Opt_sb:
1532                 return 1;       /* handled by get_sb_block() */
1533         case Opt_removed:
1534                 ext4_msg(sb, KERN_WARNING,
1535                          "Ignoring removed %s option", opt);
1536                 return 1;
1537         case Opt_resuid:
1538                 uid = make_kuid(current_user_ns(), arg);
1539                 if (!uid_valid(uid)) {
1540                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1541                         return -1;
1542                 }
1543                 sbi->s_resuid = uid;
1544                 return 1;
1545         case Opt_resgid:
1546                 gid = make_kgid(current_user_ns(), arg);
1547                 if (!gid_valid(gid)) {
1548                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1549                         return -1;
1550                 }
1551                 sbi->s_resgid = gid;
1552                 return 1;
1553         case Opt_abort:
1554                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1555                 return 1;
1556         case Opt_i_version:
1557                 sb->s_flags |= MS_I_VERSION;
1558                 return 1;
1559         case Opt_journal_dev:
1560                 if (is_remount) {
1561                         ext4_msg(sb, KERN_ERR,
1562                                  "Cannot specify journal on remount");
1563                         return -1;
1564                 }
1565                 *journal_devnum = arg;
1566                 return 1;
1567         case Opt_journal_ioprio:
1568                 if (arg < 0 || arg > 7)
1569                         return -1;
1570                 *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1571                 return 1;
1572         }
1573
1574         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1575                 if (token != m->token)
1576                         continue;
1577                 if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1578                         return -1;
1579                 if (m->flags & MOPT_EXPLICIT)
1580                         set_opt2(sb, EXPLICIT_DELALLOC);
1581                 if (m->flags & MOPT_CLEAR_ERR)
1582                         clear_opt(sb, ERRORS_MASK);
1583                 if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1584                         ext4_msg(sb, KERN_ERR, "Cannot change quota "
1585                                  "options when quota turned on");
1586                         return -1;
1587                 }
1588
1589                 if (m->flags & MOPT_NOSUPPORT) {
1590                         ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1591                 } else if (token == Opt_commit) {
1592                         if (arg == 0)
1593                                 arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1594                         sbi->s_commit_interval = HZ * arg;
1595                 } else if (token == Opt_max_batch_time) {
1596                         if (arg == 0)
1597                                 arg = EXT4_DEF_MAX_BATCH_TIME;
1598                         sbi->s_max_batch_time = arg;
1599                 } else if (token == Opt_min_batch_time) {
1600                         sbi->s_min_batch_time = arg;
1601                 } else if (token == Opt_inode_readahead_blks) {
1602                         if (arg > (1 << 30))
1603                                 return -1;
1604                         if (arg && !is_power_of_2(arg)) {
1605                                 ext4_msg(sb, KERN_ERR,
1606                                          "EXT4-fs: inode_readahead_blks"
1607                                          " must be a power of 2");
1608                                 return -1;
1609                         }
1610                         sbi->s_inode_readahead_blks = arg;
1611                 } else if (token == Opt_init_itable) {
1612                         set_opt(sb, INIT_INODE_TABLE);
1613                         if (!args->from)
1614                                 arg = EXT4_DEF_LI_WAIT_MULT;
1615                         sbi->s_li_wait_mult = arg;
1616                 } else if (token == Opt_stripe) {
1617                         sbi->s_stripe = arg;
1618                 } else if (m->flags & MOPT_DATAJ) {
1619                         if (is_remount) {
1620                                 if (!sbi->s_journal)
1621                                         ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1622                                 else if (test_opt(sb, DATA_FLAGS) !=
1623                                          m->mount_opt) {
1624                                         ext4_msg(sb, KERN_ERR,
1625                                          "Cannot change data mode on remount");
1626                                         return -1;
1627                                 }
1628                         } else {
1629                                 clear_opt(sb, DATA_FLAGS);
1630                                 sbi->s_mount_opt |= m->mount_opt;
1631                         }
1632 #ifdef CONFIG_QUOTA
1633                 } else if (m->flags & MOPT_QFMT) {
1634                         if (sb_any_quota_loaded(sb) &&
1635                             sbi->s_jquota_fmt != m->mount_opt) {
1636                                 ext4_msg(sb, KERN_ERR, "Cannot "
1637                                          "change journaled quota options "
1638                                          "when quota turned on");
1639                                 return -1;
1640                         }
1641                         sbi->s_jquota_fmt = m->mount_opt;
1642 #endif
1643                 } else {
1644                         if (!args->from)
1645                                 arg = 1;
1646                         if (m->flags & MOPT_CLEAR)
1647                                 arg = !arg;
1648                         else if (unlikely(!(m->flags & MOPT_SET))) {
1649                                 ext4_msg(sb, KERN_WARNING,
1650                                          "buggy handling of option %s", opt);
1651                                 WARN_ON(1);
1652                                 return -1;
1653                         }
1654                         if (arg != 0)
1655                                 sbi->s_mount_opt |= m->mount_opt;
1656                         else
1657                                 sbi->s_mount_opt &= ~m->mount_opt;
1658                 }
1659                 return 1;
1660         }
1661         ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1662                  "or missing value", opt);
1663         return -1;
1664 }
1665
1666 static int parse_options(char *options, struct super_block *sb,
1667                          unsigned long *journal_devnum,
1668                          unsigned int *journal_ioprio,
1669                          int is_remount)
1670 {
1671 #ifdef CONFIG_QUOTA
1672         struct ext4_sb_info *sbi = EXT4_SB(sb);
1673 #endif
1674         char *p;
1675         substring_t args[MAX_OPT_ARGS];
1676         int token;
1677
1678         if (!options)
1679                 return 1;
1680
1681         while ((p = strsep(&options, ",")) != NULL) {
1682                 if (!*p)
1683                         continue;
1684                 /*
1685                  * Initialize args struct so we know whether arg was
1686                  * found; some options take optional arguments.
1687                  */
1688                 args[0].to = args[0].from = 0;
1689                 token = match_token(p, tokens, args);
1690                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1691                                      journal_ioprio, is_remount) < 0)
1692                         return 0;
1693         }
1694 #ifdef CONFIG_QUOTA
1695         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1696                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1697                         clear_opt(sb, USRQUOTA);
1698
1699                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1700                         clear_opt(sb, GRPQUOTA);
1701
1702                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1703                         ext4_msg(sb, KERN_ERR, "old and new quota "
1704                                         "format mixing");
1705                         return 0;
1706                 }
1707
1708                 if (!sbi->s_jquota_fmt) {
1709                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1710                                         "not specified");
1711                         return 0;
1712                 }
1713         } else {
1714                 if (sbi->s_jquota_fmt) {
1715                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1716                                         "specified with no journaling "
1717                                         "enabled");
1718                         return 0;
1719                 }
1720         }
1721 #endif
1722         return 1;
1723 }
1724
1725 static inline void ext4_show_quota_options(struct seq_file *seq,
1726                                            struct super_block *sb)
1727 {
1728 #if defined(CONFIG_QUOTA)
1729         struct ext4_sb_info *sbi = EXT4_SB(sb);
1730
1731         if (sbi->s_jquota_fmt) {
1732                 char *fmtname = "";
1733
1734                 switch (sbi->s_jquota_fmt) {
1735                 case QFMT_VFS_OLD:
1736                         fmtname = "vfsold";
1737                         break;
1738                 case QFMT_VFS_V0:
1739                         fmtname = "vfsv0";
1740                         break;
1741                 case QFMT_VFS_V1:
1742                         fmtname = "vfsv1";
1743                         break;
1744                 }
1745                 seq_printf(seq, ",jqfmt=%s", fmtname);
1746         }
1747
1748         if (sbi->s_qf_names[USRQUOTA])
1749                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1750
1751         if (sbi->s_qf_names[GRPQUOTA])
1752                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1753
1754         if (test_opt(sb, USRQUOTA))
1755                 seq_puts(seq, ",usrquota");
1756
1757         if (test_opt(sb, GRPQUOTA))
1758                 seq_puts(seq, ",grpquota");
1759 #endif
1760 }
1761
1762 static const char *token2str(int token)
1763 {
1764         static const struct match_token *t;
1765
1766         for (t = tokens; t->token != Opt_err; t++)
1767                 if (t->token == token && !strchr(t->pattern, '='))
1768                         break;
1769         return t->pattern;
1770 }
1771
1772 /*
1773  * Show an option if
1774  *  - it's set to a non-default value OR
1775  *  - if the per-sb default is different from the global default
1776  */
1777 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1778                               int nodefs)
1779 {
1780         struct ext4_sb_info *sbi = EXT4_SB(sb);
1781         struct ext4_super_block *es = sbi->s_es;
1782         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1783         const struct mount_opts *m;
1784         char sep = nodefs ? '\n' : ',';
1785
1786 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1787 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1788
1789         if (sbi->s_sb_block != 1)
1790                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1791
1792         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1793                 int want_set = m->flags & MOPT_SET;
1794                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1795                     (m->flags & MOPT_CLEAR_ERR))
1796                         continue;
1797                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1798                         continue; /* skip if same as the default */
1799                 if ((want_set &&
1800                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1801                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1802                         continue; /* select Opt_noFoo vs Opt_Foo */
1803                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1804         }
1805
1806         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1807             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1808                 SEQ_OPTS_PRINT("resuid=%u",
1809                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1810         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1811             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1812                 SEQ_OPTS_PRINT("resgid=%u",
1813                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1814         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1815         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1816                 SEQ_OPTS_PUTS("errors=remount-ro");
1817         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1818                 SEQ_OPTS_PUTS("errors=continue");
1819         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1820                 SEQ_OPTS_PUTS("errors=panic");
1821         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1822                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1823         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1824                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1825         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1826                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1827         if (sb->s_flags & MS_I_VERSION)
1828                 SEQ_OPTS_PUTS("i_version");
1829         if (nodefs || sbi->s_stripe)
1830                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1831         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1832                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1833                         SEQ_OPTS_PUTS("data=journal");
1834                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1835                         SEQ_OPTS_PUTS("data=ordered");
1836                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1837                         SEQ_OPTS_PUTS("data=writeback");
1838         }
1839         if (nodefs ||
1840             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1841                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1842                                sbi->s_inode_readahead_blks);
1843
1844         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1845                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1846                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1847
1848         ext4_show_quota_options(seq, sb);
1849         return 0;
1850 }
1851
1852 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1853 {
1854         return _ext4_show_options(seq, root->d_sb, 0);
1855 }
1856
1857 static int options_seq_show(struct seq_file *seq, void *offset)
1858 {
1859         struct super_block *sb = seq->private;
1860         int rc;
1861
1862         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1863         rc = _ext4_show_options(seq, sb, 1);
1864         seq_puts(seq, "\n");
1865         return rc;
1866 }
1867
1868 static int options_open_fs(struct inode *inode, struct file *file)
1869 {
1870         return single_open(file, options_seq_show, PDE(inode)->data);
1871 }
1872
1873 static const struct file_operations ext4_seq_options_fops = {
1874         .owner = THIS_MODULE,
1875         .open = options_open_fs,
1876         .read = seq_read,
1877         .llseek = seq_lseek,
1878         .release = single_release,
1879 };
1880
1881 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1882                             int read_only)
1883 {
1884         struct ext4_sb_info *sbi = EXT4_SB(sb);
1885         int res = 0;
1886
1887         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1888                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1889                          "forcing read-only mode");
1890                 res = MS_RDONLY;
1891         }
1892         if (read_only)
1893                 goto done;
1894         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1895                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1896                          "running e2fsck is recommended");
1897         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1898                 ext4_msg(sb, KERN_WARNING,
1899                          "warning: mounting fs with errors, "
1900                          "running e2fsck is recommended");
1901         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1902                  le16_to_cpu(es->s_mnt_count) >=
1903                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1904                 ext4_msg(sb, KERN_WARNING,
1905                          "warning: maximal mount count reached, "
1906                          "running e2fsck is recommended");
1907         else if (le32_to_cpu(es->s_checkinterval) &&
1908                 (le32_to_cpu(es->s_lastcheck) +
1909                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1910                 ext4_msg(sb, KERN_WARNING,
1911                          "warning: checktime reached, "
1912                          "running e2fsck is recommended");
1913         if (!sbi->s_journal)
1914                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1915         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1916                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1917         le16_add_cpu(&es->s_mnt_count, 1);
1918         es->s_mtime = cpu_to_le32(get_seconds());
1919         ext4_update_dynamic_rev(sb);
1920         if (sbi->s_journal)
1921                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1922
1923         ext4_commit_super(sb, 1);
1924 done:
1925         if (test_opt(sb, DEBUG))
1926                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1927                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1928                         sb->s_blocksize,
1929                         sbi->s_groups_count,
1930                         EXT4_BLOCKS_PER_GROUP(sb),
1931                         EXT4_INODES_PER_GROUP(sb),
1932                         sbi->s_mount_opt, sbi->s_mount_opt2);
1933
1934         cleancache_init_fs(sb);
1935         return res;
1936 }
1937
1938 static int ext4_fill_flex_info(struct super_block *sb)
1939 {
1940         struct ext4_sb_info *sbi = EXT4_SB(sb);
1941         struct ext4_group_desc *gdp = NULL;
1942         ext4_group_t flex_group_count;
1943         ext4_group_t flex_group;
1944         unsigned int groups_per_flex = 0;
1945         size_t size;
1946         int i;
1947
1948         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1949         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1950                 sbi->s_log_groups_per_flex = 0;
1951                 return 1;
1952         }
1953         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1954
1955         /* We allocate both existing and potentially added groups */
1956         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1957                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1958                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1959         size = flex_group_count * sizeof(struct flex_groups);
1960         sbi->s_flex_groups = ext4_kvzalloc(size, GFP_KERNEL);
1961         if (sbi->s_flex_groups == NULL) {
1962                 ext4_msg(sb, KERN_ERR, "not enough memory for %u flex groups",
1963                          flex_group_count);
1964                 goto failed;
1965         }
1966
1967         for (i = 0; i < sbi->s_groups_count; i++) {
1968                 gdp = ext4_get_group_desc(sb, i, NULL);
1969
1970                 flex_group = ext4_flex_group(sbi, i);
1971                 atomic_add(ext4_free_inodes_count(sb, gdp),
1972                            &sbi->s_flex_groups[flex_group].free_inodes);
1973                 atomic_add(ext4_free_group_clusters(sb, gdp),
1974                            &sbi->s_flex_groups[flex_group].free_clusters);
1975                 atomic_add(ext4_used_dirs_count(sb, gdp),
1976                            &sbi->s_flex_groups[flex_group].used_dirs);
1977         }
1978
1979         return 1;
1980 failed:
1981         return 0;
1982 }
1983
1984 static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1985                                    struct ext4_group_desc *gdp)
1986 {
1987         int offset;
1988         __u16 crc = 0;
1989         __le32 le_group = cpu_to_le32(block_group);
1990
1991         if ((sbi->s_es->s_feature_ro_compat &
1992              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))) {
1993                 /* Use new metadata_csum algorithm */
1994                 __u16 old_csum;
1995                 __u32 csum32;
1996
1997                 old_csum = gdp->bg_checksum;
1998                 gdp->bg_checksum = 0;
1999                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2000                                      sizeof(le_group));
2001                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
2002                                      sbi->s_desc_size);
2003                 gdp->bg_checksum = old_csum;
2004
2005                 crc = csum32 & 0xFFFF;
2006                 goto out;
2007         }
2008
2009         /* old crc16 code */
2010         offset = offsetof(struct ext4_group_desc, bg_checksum);
2011
2012         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2013         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2014         crc = crc16(crc, (__u8 *)gdp, offset);
2015         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2016         /* for checksum of struct ext4_group_desc do the rest...*/
2017         if ((sbi->s_es->s_feature_incompat &
2018              cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2019             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2020                 crc = crc16(crc, (__u8 *)gdp + offset,
2021                             le16_to_cpu(sbi->s_es->s_desc_size) -
2022                                 offset);
2023
2024 out:
2025         return cpu_to_le16(crc);
2026 }
2027
2028 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2029                                 struct ext4_group_desc *gdp)
2030 {
2031         if (ext4_has_group_desc_csum(sb) &&
2032             (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
2033                                                       block_group, gdp)))
2034                 return 0;
2035
2036         return 1;
2037 }
2038
2039 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2040                               struct ext4_group_desc *gdp)
2041 {
2042         if (!ext4_has_group_desc_csum(sb))
2043                 return;
2044         gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
2045 }
2046
2047 /* Called at mount-time, super-block is locked */
2048 static int ext4_check_descriptors(struct super_block *sb,
2049                                   ext4_group_t *first_not_zeroed)
2050 {
2051         struct ext4_sb_info *sbi = EXT4_SB(sb);
2052         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2053         ext4_fsblk_t last_block;
2054         ext4_fsblk_t block_bitmap;
2055         ext4_fsblk_t inode_bitmap;
2056         ext4_fsblk_t inode_table;
2057         int flexbg_flag = 0;
2058         ext4_group_t i, grp = sbi->s_groups_count;
2059
2060         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2061                 flexbg_flag = 1;
2062
2063         ext4_debug("Checking group descriptors");
2064
2065         for (i = 0; i < sbi->s_groups_count; i++) {
2066                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2067
2068                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2069                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2070                 else
2071                         last_block = first_block +
2072                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2073
2074                 if ((grp == sbi->s_groups_count) &&
2075                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2076                         grp = i;
2077
2078                 block_bitmap = ext4_block_bitmap(sb, gdp);
2079                 if (block_bitmap < first_block || block_bitmap > last_block) {
2080                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2081                                "Block bitmap for group %u not in group "
2082                                "(block %llu)!", i, block_bitmap);
2083                         return 0;
2084                 }
2085                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2086                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2087                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2088                                "Inode bitmap for group %u not in group "
2089                                "(block %llu)!", i, inode_bitmap);
2090                         return 0;
2091                 }
2092                 inode_table = ext4_inode_table(sb, gdp);
2093                 if (inode_table < first_block ||
2094                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2095                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2096                                "Inode table for group %u not in group "
2097                                "(block %llu)!", i, inode_table);
2098                         return 0;
2099                 }
2100                 ext4_lock_group(sb, i);
2101                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2102                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2103                                  "Checksum for group %u failed (%u!=%u)",
2104                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2105                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2106                         if (!(sb->s_flags & MS_RDONLY)) {
2107                                 ext4_unlock_group(sb, i);
2108                                 return 0;
2109                         }
2110                 }
2111                 ext4_unlock_group(sb, i);
2112                 if (!flexbg_flag)
2113                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2114         }
2115         if (NULL != first_not_zeroed)
2116                 *first_not_zeroed = grp;
2117
2118         ext4_free_blocks_count_set(sbi->s_es,
2119                                    EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2120         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2121         return 1;
2122 }
2123
2124 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2125  * the superblock) which were deleted from all directories, but held open by
2126  * a process at the time of a crash.  We walk the list and try to delete these
2127  * inodes at recovery time (only with a read-write filesystem).
2128  *
2129  * In order to keep the orphan inode chain consistent during traversal (in
2130  * case of crash during recovery), we link each inode into the superblock
2131  * orphan list_head and handle it the same way as an inode deletion during
2132  * normal operation (which journals the operations for us).
2133  *
2134  * We only do an iget() and an iput() on each inode, which is very safe if we
2135  * accidentally point at an in-use or already deleted inode.  The worst that
2136  * can happen in this case is that we get a "bit already cleared" message from
2137  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2138  * e2fsck was run on this filesystem, and it must have already done the orphan
2139  * inode cleanup for us, so we can safely abort without any further action.
2140  */
2141 static void ext4_orphan_cleanup(struct super_block *sb,
2142                                 struct ext4_super_block *es)
2143 {
2144         unsigned int s_flags = sb->s_flags;
2145         int nr_orphans = 0, nr_truncates = 0;
2146 #ifdef CONFIG_QUOTA
2147         int i;
2148 #endif
2149         if (!es->s_last_orphan) {
2150                 jbd_debug(4, "no orphan inodes to clean up\n");
2151                 return;
2152         }
2153
2154         if (bdev_read_only(sb->s_bdev)) {
2155                 ext4_msg(sb, KERN_ERR, "write access "
2156                         "unavailable, skipping orphan cleanup");
2157                 return;
2158         }
2159
2160         /* Check if feature set would not allow a r/w mount */
2161         if (!ext4_feature_set_ok(sb, 0)) {
2162                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2163                          "unknown ROCOMPAT features");
2164                 return;
2165         }
2166
2167         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2168                 if (es->s_last_orphan)
2169                         jbd_debug(1, "Errors on filesystem, "
2170                                   "clearing orphan list.\n");
2171                 es->s_last_orphan = 0;
2172                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2173                 return;
2174         }
2175
2176         if (s_flags & MS_RDONLY) {
2177                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2178                 sb->s_flags &= ~MS_RDONLY;
2179         }
2180 #ifdef CONFIG_QUOTA
2181         /* Needed for iput() to work correctly and not trash data */
2182         sb->s_flags |= MS_ACTIVE;
2183         /* Turn on quotas so that they are updated correctly */
2184         for (i = 0; i < MAXQUOTAS; i++) {
2185                 if (EXT4_SB(sb)->s_qf_names[i]) {
2186                         int ret = ext4_quota_on_mount(sb, i);
2187                         if (ret < 0)
2188                                 ext4_msg(sb, KERN_ERR,
2189                                         "Cannot turn on journaled "
2190                                         "quota: error %d", ret);
2191                 }
2192         }
2193 #endif
2194
2195         while (es->s_last_orphan) {
2196                 struct inode *inode;
2197
2198                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2199                 if (IS_ERR(inode)) {
2200                         es->s_last_orphan = 0;
2201                         break;
2202                 }
2203
2204                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2205                 dquot_initialize(inode);
2206                 if (inode->i_nlink) {
2207                         ext4_msg(sb, KERN_DEBUG,
2208                                 "%s: truncating inode %lu to %lld bytes",
2209                                 __func__, inode->i_ino, inode->i_size);
2210                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2211                                   inode->i_ino, inode->i_size);
2212                         ext4_truncate(inode);
2213                         nr_truncates++;
2214                 } else {
2215                         ext4_msg(sb, KERN_DEBUG,
2216                                 "%s: deleting unreferenced inode %lu",
2217                                 __func__, inode->i_ino);
2218                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2219                                   inode->i_ino);
2220                         nr_orphans++;
2221                 }
2222                 iput(inode);  /* The delete magic happens here! */
2223         }
2224
2225 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2226
2227         if (nr_orphans)
2228                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2229                        PLURAL(nr_orphans));
2230         if (nr_truncates)
2231                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2232                        PLURAL(nr_truncates));
2233 #ifdef CONFIG_QUOTA
2234         /* Turn quotas off */
2235         for (i = 0; i < MAXQUOTAS; i++) {
2236                 if (sb_dqopt(sb)->files[i])
2237                         dquot_quota_off(sb, i);
2238         }
2239 #endif
2240         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2241 }
2242
2243 /*
2244  * Maximal extent format file size.
2245  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2246  * extent format containers, within a sector_t, and within i_blocks
2247  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2248  * so that won't be a limiting factor.
2249  *
2250  * However there is other limiting factor. We do store extents in the form
2251  * of starting block and length, hence the resulting length of the extent
2252  * covering maximum file size must fit into on-disk format containers as
2253  * well. Given that length is always by 1 unit bigger than max unit (because
2254  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2255  *
2256  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2257  */
2258 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2259 {
2260         loff_t res;
2261         loff_t upper_limit = MAX_LFS_FILESIZE;
2262
2263         /* small i_blocks in vfs inode? */
2264         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2265                 /*
2266                  * CONFIG_LBDAF is not enabled implies the inode
2267                  * i_block represent total blocks in 512 bytes
2268                  * 32 == size of vfs inode i_blocks * 8
2269                  */
2270                 upper_limit = (1LL << 32) - 1;
2271
2272                 /* total blocks in file system block size */
2273                 upper_limit >>= (blkbits - 9);
2274                 upper_limit <<= blkbits;
2275         }
2276
2277         /*
2278          * 32-bit extent-start container, ee_block. We lower the maxbytes
2279          * by one fs block, so ee_len can cover the extent of maximum file
2280          * size
2281          */
2282         res = (1LL << 32) - 1;
2283         res <<= blkbits;
2284
2285         /* Sanity check against vm- & vfs- imposed limits */
2286         if (res > upper_limit)
2287                 res = upper_limit;
2288
2289         return res;
2290 }
2291
2292 /*
2293  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2294  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2295  * We need to be 1 filesystem block less than the 2^48 sector limit.
2296  */
2297 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2298 {
2299         loff_t res = EXT4_NDIR_BLOCKS;
2300         int meta_blocks;
2301         loff_t upper_limit;
2302         /* This is calculated to be the largest file size for a dense, block
2303          * mapped file such that the file's total number of 512-byte sectors,
2304          * including data and all indirect blocks, does not exceed (2^48 - 1).
2305          *
2306          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2307          * number of 512-byte sectors of the file.
2308          */
2309
2310         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2311                 /*
2312                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2313                  * the inode i_block field represents total file blocks in
2314                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2315                  */
2316                 upper_limit = (1LL << 32) - 1;
2317
2318                 /* total blocks in file system block size */
2319                 upper_limit >>= (bits - 9);
2320
2321         } else {
2322                 /*
2323                  * We use 48 bit ext4_inode i_blocks
2324                  * With EXT4_HUGE_FILE_FL set the i_blocks
2325                  * represent total number of blocks in
2326                  * file system block size
2327                  */
2328                 upper_limit = (1LL << 48) - 1;
2329
2330         }
2331
2332         /* indirect blocks */
2333         meta_blocks = 1;
2334         /* double indirect blocks */
2335         meta_blocks += 1 + (1LL << (bits-2));
2336         /* tripple indirect blocks */
2337         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2338
2339         upper_limit -= meta_blocks;
2340         upper_limit <<= bits;
2341
2342         res += 1LL << (bits-2);
2343         res += 1LL << (2*(bits-2));
2344         res += 1LL << (3*(bits-2));
2345         res <<= bits;
2346         if (res > upper_limit)
2347                 res = upper_limit;
2348
2349         if (res > MAX_LFS_FILESIZE)
2350                 res = MAX_LFS_FILESIZE;
2351
2352         return res;
2353 }
2354
2355 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2356                                    ext4_fsblk_t logical_sb_block, int nr)
2357 {
2358         struct ext4_sb_info *sbi = EXT4_SB(sb);
2359         ext4_group_t bg, first_meta_bg;
2360         int has_super = 0;
2361
2362         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2363
2364         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2365             nr < first_meta_bg)
2366                 return logical_sb_block + nr + 1;
2367         bg = sbi->s_desc_per_block * nr;
2368         if (ext4_bg_has_super(sb, bg))
2369                 has_super = 1;
2370
2371         return (has_super + ext4_group_first_block_no(sb, bg));
2372 }
2373
2374 /**
2375  * ext4_get_stripe_size: Get the stripe size.
2376  * @sbi: In memory super block info
2377  *
2378  * If we have specified it via mount option, then
2379  * use the mount option value. If the value specified at mount time is
2380  * greater than the blocks per group use the super block value.
2381  * If the super block value is greater than blocks per group return 0.
2382  * Allocator needs it be less than blocks per group.
2383  *
2384  */
2385 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2386 {
2387         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2388         unsigned long stripe_width =
2389                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2390         int ret;
2391
2392         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2393                 ret = sbi->s_stripe;
2394         else if (stripe_width <= sbi->s_blocks_per_group)
2395                 ret = stripe_width;
2396         else if (stride <= sbi->s_blocks_per_group)
2397                 ret = stride;
2398         else
2399                 ret = 0;
2400
2401         /*
2402          * If the stripe width is 1, this makes no sense and
2403          * we set it to 0 to turn off stripe handling code.
2404          */
2405         if (ret <= 1)
2406                 ret = 0;
2407
2408         return ret;
2409 }
2410
2411 /* sysfs supprt */
2412
2413 struct ext4_attr {
2414         struct attribute attr;
2415         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2416         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2417                          const char *, size_t);
2418         int offset;
2419 };
2420
2421 static int parse_strtoul(const char *buf,
2422                 unsigned long max, unsigned long *value)
2423 {
2424         char *endp;
2425
2426         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2427         endp = skip_spaces(endp);
2428         if (*endp || *value > max)
2429                 return -EINVAL;
2430
2431         return 0;
2432 }
2433
2434 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2435                                               struct ext4_sb_info *sbi,
2436                                               char *buf)
2437 {
2438         return snprintf(buf, PAGE_SIZE, "%llu\n",
2439                 (s64) EXT4_C2B(sbi,
2440                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2441 }
2442
2443 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2444                                          struct ext4_sb_info *sbi, char *buf)
2445 {
2446         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2447
2448         if (!sb->s_bdev->bd_part)
2449                 return snprintf(buf, PAGE_SIZE, "0\n");
2450         return snprintf(buf, PAGE_SIZE, "%lu\n",
2451                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2452                          sbi->s_sectors_written_start) >> 1);
2453 }
2454
2455 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2456                                           struct ext4_sb_info *sbi, char *buf)
2457 {
2458         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2459
2460         if (!sb->s_bdev->bd_part)
2461                 return snprintf(buf, PAGE_SIZE, "0\n");
2462         return snprintf(buf, PAGE_SIZE, "%llu\n",
2463                         (unsigned long long)(sbi->s_kbytes_written +
2464                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2465                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2466 }
2467
2468 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2469                                           struct ext4_sb_info *sbi,
2470                                           const char *buf, size_t count)
2471 {
2472         unsigned long t;
2473
2474         if (parse_strtoul(buf, 0x40000000, &t))
2475                 return -EINVAL;
2476
2477         if (t && !is_power_of_2(t))
2478                 return -EINVAL;
2479
2480         sbi->s_inode_readahead_blks = t;
2481         return count;
2482 }
2483
2484 static ssize_t sbi_ui_show(struct ext4_attr *a,
2485                            struct ext4_sb_info *sbi, char *buf)
2486 {
2487         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2488
2489         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2490 }
2491
2492 static ssize_t sbi_ui_store(struct ext4_attr *a,
2493                             struct ext4_sb_info *sbi,
2494                             const char *buf, size_t count)
2495 {
2496         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2497         unsigned long t;
2498
2499         if (parse_strtoul(buf, 0xffffffff, &t))
2500                 return -EINVAL;
2501         *ui = t;
2502         return count;
2503 }
2504
2505 static ssize_t trigger_test_error(struct ext4_attr *a,
2506                                   struct ext4_sb_info *sbi,
2507                                   const char *buf, size_t count)
2508 {
2509         int len = count;
2510
2511         if (!capable(CAP_SYS_ADMIN))
2512                 return -EPERM;
2513
2514         if (len && buf[len-1] == '\n')
2515                 len--;
2516
2517         if (len)
2518                 ext4_error(sbi->s_sb, "%.*s", len, buf);
2519         return count;
2520 }
2521
2522 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2523 static struct ext4_attr ext4_attr_##_name = {                   \
2524         .attr = {.name = __stringify(_name), .mode = _mode },   \
2525         .show   = _show,                                        \
2526         .store  = _store,                                       \
2527         .offset = offsetof(struct ext4_sb_info, _elname),       \
2528 }
2529 #define EXT4_ATTR(name, mode, show, store) \
2530 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2531
2532 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2533 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2534 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2535 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2536         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2537 #define ATTR_LIST(name) &ext4_attr_##name.attr
2538
2539 EXT4_RO_ATTR(delayed_allocation_blocks);
2540 EXT4_RO_ATTR(session_write_kbytes);
2541 EXT4_RO_ATTR(lifetime_write_kbytes);
2542 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2543                  inode_readahead_blks_store, s_inode_readahead_blks);
2544 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2545 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2546 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2547 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2548 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2549 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2550 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2551 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2552 EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error);
2553
2554 static struct attribute *ext4_attrs[] = {
2555         ATTR_LIST(delayed_allocation_blocks),
2556         ATTR_LIST(session_write_kbytes),
2557         ATTR_LIST(lifetime_write_kbytes),
2558         ATTR_LIST(inode_readahead_blks),
2559         ATTR_LIST(inode_goal),
2560         ATTR_LIST(mb_stats),
2561         ATTR_LIST(mb_max_to_scan),
2562         ATTR_LIST(mb_min_to_scan),
2563         ATTR_LIST(mb_order2_req),
2564         ATTR_LIST(mb_stream_req),
2565         ATTR_LIST(mb_group_prealloc),
2566         ATTR_LIST(max_writeback_mb_bump),
2567         ATTR_LIST(trigger_fs_error),
2568         NULL,
2569 };
2570
2571 /* Features this copy of ext4 supports */
2572 EXT4_INFO_ATTR(lazy_itable_init);
2573 EXT4_INFO_ATTR(batched_discard);
2574
2575 static struct attribute *ext4_feat_attrs[] = {
2576         ATTR_LIST(lazy_itable_init),
2577         ATTR_LIST(batched_discard),
2578         NULL,
2579 };
2580
2581 static ssize_t ext4_attr_show(struct kobject *kobj,
2582                               struct attribute *attr, char *buf)
2583 {
2584         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2585                                                 s_kobj);
2586         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2587
2588         return a->show ? a->show(a, sbi, buf) : 0;
2589 }
2590
2591 static ssize_t ext4_attr_store(struct kobject *kobj,
2592                                struct attribute *attr,
2593                                const char *buf, size_t len)
2594 {
2595         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2596                                                 s_kobj);
2597         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2598
2599         return a->store ? a->store(a, sbi, buf, len) : 0;
2600 }
2601
2602 static void ext4_sb_release(struct kobject *kobj)
2603 {
2604         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2605                                                 s_kobj);
2606         complete(&sbi->s_kobj_unregister);
2607 }
2608
2609 static const struct sysfs_ops ext4_attr_ops = {
2610         .show   = ext4_attr_show,
2611         .store  = ext4_attr_store,
2612 };
2613
2614 static struct kobj_type ext4_ktype = {
2615         .default_attrs  = ext4_attrs,
2616         .sysfs_ops      = &ext4_attr_ops,
2617         .release        = ext4_sb_release,
2618 };
2619
2620 static void ext4_feat_release(struct kobject *kobj)
2621 {
2622         complete(&ext4_feat->f_kobj_unregister);
2623 }
2624
2625 static struct kobj_type ext4_feat_ktype = {
2626         .default_attrs  = ext4_feat_attrs,
2627         .sysfs_ops      = &ext4_attr_ops,
2628         .release        = ext4_feat_release,
2629 };
2630
2631 /*
2632  * Check whether this filesystem can be mounted based on
2633  * the features present and the RDONLY/RDWR mount requested.
2634  * Returns 1 if this filesystem can be mounted as requested,
2635  * 0 if it cannot be.
2636  */
2637 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2638 {
2639         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2640                 ext4_msg(sb, KERN_ERR,
2641                         "Couldn't mount because of "
2642                         "unsupported optional features (%x)",
2643                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2644                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2645                 return 0;
2646         }
2647
2648         if (readonly)
2649                 return 1;
2650
2651         /* Check that feature set is OK for a read-write mount */
2652         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2653                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2654                          "unsupported optional features (%x)",
2655                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2656                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2657                 return 0;
2658         }
2659         /*
2660          * Large file size enabled file system can only be mounted
2661          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2662          */
2663         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2664                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2665                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2666                                  "cannot be mounted RDWR without "
2667                                  "CONFIG_LBDAF");
2668                         return 0;
2669                 }
2670         }
2671         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2672             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2673                 ext4_msg(sb, KERN_ERR,
2674                          "Can't support bigalloc feature without "
2675                          "extents feature\n");
2676                 return 0;
2677         }
2678
2679 #ifndef CONFIG_QUOTA
2680         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
2681             !readonly) {
2682                 ext4_msg(sb, KERN_ERR,
2683                          "Filesystem with quota feature cannot be mounted RDWR "
2684                          "without CONFIG_QUOTA");
2685                 return 0;
2686         }
2687 #endif  /* CONFIG_QUOTA */
2688         return 1;
2689 }
2690
2691 /*
2692  * This function is called once a day if we have errors logged
2693  * on the file system
2694  */
2695 static void print_daily_error_info(unsigned long arg)
2696 {
2697         struct super_block *sb = (struct super_block *) arg;
2698         struct ext4_sb_info *sbi;
2699         struct ext4_super_block *es;
2700
2701         sbi = EXT4_SB(sb);
2702         es = sbi->s_es;
2703
2704         if (es->s_error_count)
2705                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2706                          le32_to_cpu(es->s_error_count));
2707         if (es->s_first_error_time) {
2708                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2709                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2710                        (int) sizeof(es->s_first_error_func),
2711                        es->s_first_error_func,
2712                        le32_to_cpu(es->s_first_error_line));
2713                 if (es->s_first_error_ino)
2714                         printk(": inode %u",
2715                                le32_to_cpu(es->s_first_error_ino));
2716                 if (es->s_first_error_block)
2717                         printk(": block %llu", (unsigned long long)
2718                                le64_to_cpu(es->s_first_error_block));
2719                 printk("\n");
2720         }
2721         if (es->s_last_error_time) {
2722                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2723                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2724                        (int) sizeof(es->s_last_error_func),
2725                        es->s_last_error_func,
2726                        le32_to_cpu(es->s_last_error_line));
2727                 if (es->s_last_error_ino)
2728                         printk(": inode %u",
2729                                le32_to_cpu(es->s_last_error_ino));
2730                 if (es->s_last_error_block)
2731                         printk(": block %llu", (unsigned long long)
2732                                le64_to_cpu(es->s_last_error_block));
2733                 printk("\n");
2734         }
2735         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2736 }
2737
2738 /* Find next suitable group and run ext4_init_inode_table */
2739 static int ext4_run_li_request(struct ext4_li_request *elr)
2740 {
2741         struct ext4_group_desc *gdp = NULL;
2742         ext4_group_t group, ngroups;
2743         struct super_block *sb;
2744         unsigned long timeout = 0;
2745         int ret = 0;
2746
2747         sb = elr->lr_super;
2748         ngroups = EXT4_SB(sb)->s_groups_count;
2749
2750         for (group = elr->lr_next_group; group < ngroups; group++) {
2751                 gdp = ext4_get_group_desc(sb, group, NULL);
2752                 if (!gdp) {
2753                         ret = 1;
2754                         break;
2755                 }
2756
2757                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2758                         break;
2759         }
2760
2761         if (group == ngroups)
2762                 ret = 1;
2763
2764         if (!ret) {
2765                 timeout = jiffies;
2766                 ret = ext4_init_inode_table(sb, group,
2767                                             elr->lr_timeout ? 0 : 1);
2768                 if (elr->lr_timeout == 0) {
2769                         timeout = (jiffies - timeout) *
2770                                   elr->lr_sbi->s_li_wait_mult;
2771                         elr->lr_timeout = timeout;
2772                 }
2773                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2774                 elr->lr_next_group = group + 1;
2775         }
2776
2777         return ret;
2778 }
2779
2780 /*
2781  * Remove lr_request from the list_request and free the
2782  * request structure. Should be called with li_list_mtx held
2783  */
2784 static void ext4_remove_li_request(struct ext4_li_request *elr)
2785 {
2786         struct ext4_sb_info *sbi;
2787
2788         if (!elr)
2789                 return;
2790
2791         sbi = elr->lr_sbi;
2792
2793         list_del(&elr->lr_request);
2794         sbi->s_li_request = NULL;
2795         kfree(elr);
2796 }
2797
2798 static void ext4_unregister_li_request(struct super_block *sb)
2799 {
2800         mutex_lock(&ext4_li_mtx);
2801         if (!ext4_li_info) {
2802                 mutex_unlock(&ext4_li_mtx);
2803                 return;
2804         }
2805
2806         mutex_lock(&ext4_li_info->li_list_mtx);
2807         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2808         mutex_unlock(&ext4_li_info->li_list_mtx);
2809         mutex_unlock(&ext4_li_mtx);
2810 }
2811
2812 static struct task_struct *ext4_lazyinit_task;
2813
2814 /*
2815  * This is the function where ext4lazyinit thread lives. It walks
2816  * through the request list searching for next scheduled filesystem.
2817  * When such a fs is found, run the lazy initialization request
2818  * (ext4_rn_li_request) and keep track of the time spend in this
2819  * function. Based on that time we compute next schedule time of
2820  * the request. When walking through the list is complete, compute
2821  * next waking time and put itself into sleep.
2822  */
2823 static int ext4_lazyinit_thread(void *arg)
2824 {
2825         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2826         struct list_head *pos, *n;
2827         struct ext4_li_request *elr;
2828         unsigned long next_wakeup, cur;
2829
2830         BUG_ON(NULL == eli);
2831
2832 cont_thread:
2833         while (true) {
2834                 next_wakeup = MAX_JIFFY_OFFSET;
2835
2836                 mutex_lock(&eli->li_list_mtx);
2837                 if (list_empty(&eli->li_request_list)) {
2838                         mutex_unlock(&eli->li_list_mtx);
2839                         goto exit_thread;
2840                 }
2841
2842                 list_for_each_safe(pos, n, &eli->li_request_list) {
2843                         elr = list_entry(pos, struct ext4_li_request,
2844                                          lr_request);
2845
2846                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2847                                 if (ext4_run_li_request(elr) != 0) {
2848                                         /* error, remove the lazy_init job */
2849                                         ext4_remove_li_request(elr);
2850                                         continue;
2851                                 }
2852                         }
2853
2854                         if (time_before(elr->lr_next_sched, next_wakeup))
2855                                 next_wakeup = elr->lr_next_sched;
2856                 }
2857                 mutex_unlock(&eli->li_list_mtx);
2858
2859                 try_to_freeze();
2860
2861                 cur = jiffies;
2862                 if ((time_after_eq(cur, next_wakeup)) ||
2863                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2864                         cond_resched();
2865                         continue;
2866                 }
2867
2868                 schedule_timeout_interruptible(next_wakeup - cur);
2869
2870                 if (kthread_should_stop()) {
2871                         ext4_clear_request_list();
2872                         goto exit_thread;
2873                 }
2874         }
2875
2876 exit_thread:
2877         /*
2878          * It looks like the request list is empty, but we need
2879          * to check it under the li_list_mtx lock, to prevent any
2880          * additions into it, and of course we should lock ext4_li_mtx
2881          * to atomically free the list and ext4_li_info, because at
2882          * this point another ext4 filesystem could be registering
2883          * new one.
2884          */
2885         mutex_lock(&ext4_li_mtx);
2886         mutex_lock(&eli->li_list_mtx);
2887         if (!list_empty(&eli->li_request_list)) {
2888                 mutex_unlock(&eli->li_list_mtx);
2889                 mutex_unlock(&ext4_li_mtx);
2890                 goto cont_thread;
2891         }
2892         mutex_unlock(&eli->li_list_mtx);
2893         kfree(ext4_li_info);
2894         ext4_li_info = NULL;
2895         mutex_unlock(&ext4_li_mtx);
2896
2897         return 0;
2898 }
2899
2900 static void ext4_clear_request_list(void)
2901 {
2902         struct list_head *pos, *n;
2903         struct ext4_li_request *elr;
2904
2905         mutex_lock(&ext4_li_info->li_list_mtx);
2906         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2907                 elr = list_entry(pos, struct ext4_li_request,
2908                                  lr_request);
2909                 ext4_remove_li_request(elr);
2910         }
2911         mutex_unlock(&ext4_li_info->li_list_mtx);
2912 }
2913
2914 static int ext4_run_lazyinit_thread(void)
2915 {
2916         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2917                                          ext4_li_info, "ext4lazyinit");
2918         if (IS_ERR(ext4_lazyinit_task)) {
2919                 int err = PTR_ERR(ext4_lazyinit_task);
2920                 ext4_clear_request_list();
2921                 kfree(ext4_li_info);
2922                 ext4_li_info = NULL;
2923                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
2924                                  "initialization thread\n",
2925                                  err);
2926                 return err;
2927         }
2928         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2929         return 0;
2930 }
2931
2932 /*
2933  * Check whether it make sense to run itable init. thread or not.
2934  * If there is at least one uninitialized inode table, return
2935  * corresponding group number, else the loop goes through all
2936  * groups and return total number of groups.
2937  */
2938 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2939 {
2940         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2941         struct ext4_group_desc *gdp = NULL;
2942
2943         for (group = 0; group < ngroups; group++) {
2944                 gdp = ext4_get_group_desc(sb, group, NULL);
2945                 if (!gdp)
2946                         continue;
2947
2948                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2949                         break;
2950         }
2951
2952         return group;
2953 }
2954
2955 static int ext4_li_info_new(void)
2956 {
2957         struct ext4_lazy_init *eli = NULL;
2958
2959         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2960         if (!eli)
2961                 return -ENOMEM;
2962
2963         INIT_LIST_HEAD(&eli->li_request_list);
2964         mutex_init(&eli->li_list_mtx);
2965
2966         eli->li_state |= EXT4_LAZYINIT_QUIT;
2967
2968         ext4_li_info = eli;
2969
2970         return 0;
2971 }
2972
2973 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2974                                             ext4_group_t start)
2975 {
2976         struct ext4_sb_info *sbi = EXT4_SB(sb);
2977         struct ext4_li_request *elr;
2978         unsigned long rnd;
2979
2980         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2981         if (!elr)
2982                 return NULL;
2983
2984         elr->lr_super = sb;
2985         elr->lr_sbi = sbi;
2986         elr->lr_next_group = start;
2987
2988         /*
2989          * Randomize first schedule time of the request to
2990          * spread the inode table initialization requests
2991          * better.
2992          */
2993         get_random_bytes(&rnd, sizeof(rnd));
2994         elr->lr_next_sched = jiffies + (unsigned long)rnd %
2995                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
2996
2997         return elr;
2998 }
2999
3000 static int ext4_register_li_request(struct super_block *sb,
3001                                     ext4_group_t first_not_zeroed)
3002 {
3003         struct ext4_sb_info *sbi = EXT4_SB(sb);
3004         struct ext4_li_request *elr;
3005         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3006         int ret = 0;
3007
3008         if (sbi->s_li_request != NULL) {
3009                 /*
3010                  * Reset timeout so it can be computed again, because
3011                  * s_li_wait_mult might have changed.
3012                  */
3013                 sbi->s_li_request->lr_timeout = 0;
3014                 return 0;
3015         }
3016
3017         if (first_not_zeroed == ngroups ||
3018             (sb->s_flags & MS_RDONLY) ||
3019             !test_opt(sb, INIT_INODE_TABLE))
3020                 return 0;
3021
3022         elr = ext4_li_request_new(sb, first_not_zeroed);
3023         if (!elr)
3024                 return -ENOMEM;
3025
3026         mutex_lock(&ext4_li_mtx);
3027
3028         if (NULL == ext4_li_info) {
3029                 ret = ext4_li_info_new();
3030                 if (ret)
3031                         goto out;
3032         }
3033
3034         mutex_lock(&ext4_li_info->li_list_mtx);
3035         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3036         mutex_unlock(&ext4_li_info->li_list_mtx);
3037
3038         sbi->s_li_request = elr;
3039         /*
3040          * set elr to NULL here since it has been inserted to
3041          * the request_list and the removal and free of it is
3042          * handled by ext4_clear_request_list from now on.
3043          */
3044         elr = NULL;
3045
3046         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3047                 ret = ext4_run_lazyinit_thread();
3048                 if (ret)
3049                         goto out;
3050         }
3051 out:
3052         mutex_unlock(&ext4_li_mtx);
3053         if (ret)
3054                 kfree(elr);
3055         return ret;
3056 }
3057
3058 /*
3059  * We do not need to lock anything since this is called on
3060  * module unload.
3061  */
3062 static void ext4_destroy_lazyinit_thread(void)
3063 {
3064         /*
3065          * If thread exited earlier
3066          * there's nothing to be done.
3067          */
3068         if (!ext4_li_info || !ext4_lazyinit_task)
3069                 return;
3070
3071         kthread_stop(ext4_lazyinit_task);
3072 }
3073
3074 static int set_journal_csum_feature_set(struct super_block *sb)
3075 {
3076         int ret = 1;
3077         int compat, incompat;
3078         struct ext4_sb_info *sbi = EXT4_SB(sb);
3079
3080         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3081                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3082                 /* journal checksum v2 */
3083                 compat = 0;
3084                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V2;
3085         } else {
3086                 /* journal checksum v1 */
3087                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3088                 incompat = 0;
3089         }
3090
3091         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3092                 ret = jbd2_journal_set_features(sbi->s_journal,
3093                                 compat, 0,
3094                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3095                                 incompat);
3096         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3097                 ret = jbd2_journal_set_features(sbi->s_journal,
3098                                 compat, 0,
3099                                 incompat);
3100                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3101                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3102         } else {
3103                 jbd2_journal_clear_features(sbi->s_journal,
3104                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3105                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3106                                 JBD2_FEATURE_INCOMPAT_CSUM_V2);
3107         }
3108
3109         return ret;
3110 }
3111
3112 /*
3113  * Note: calculating the overhead so we can be compatible with
3114  * historical BSD practice is quite difficult in the face of
3115  * clusters/bigalloc.  This is because multiple metadata blocks from
3116  * different block group can end up in the same allocation cluster.
3117  * Calculating the exact overhead in the face of clustered allocation
3118  * requires either O(all block bitmaps) in memory or O(number of block
3119  * groups**2) in time.  We will still calculate the superblock for
3120  * older file systems --- and if we come across with a bigalloc file
3121  * system with zero in s_overhead_clusters the estimate will be close to
3122  * correct especially for very large cluster sizes --- but for newer
3123  * file systems, it's better to calculate this figure once at mkfs
3124  * time, and store it in the superblock.  If the superblock value is
3125  * present (even for non-bigalloc file systems), we will use it.
3126  */
3127 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3128                           char *buf)
3129 {
3130         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3131         struct ext4_group_desc  *gdp;
3132         ext4_fsblk_t            first_block, last_block, b;
3133         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3134         int                     s, j, count = 0;
3135
3136         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3137                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3138         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3139         for (i = 0; i < ngroups; i++) {
3140                 gdp = ext4_get_group_desc(sb, i, NULL);
3141                 b = ext4_block_bitmap(sb, gdp);
3142                 if (b >= first_block && b <= last_block) {
3143                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3144                         count++;
3145                 }
3146                 b = ext4_inode_bitmap(sb, gdp);
3147                 if (b >= first_block && b <= last_block) {
3148                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3149                         count++;
3150                 }
3151                 b = ext4_inode_table(sb, gdp);
3152                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3153                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3154                                 int c = EXT4_B2C(sbi, b - first_block);
3155                                 ext4_set_bit(c, buf);
3156                                 count++;
3157                         }
3158                 if (i != grp)
3159                         continue;
3160                 s = 0;
3161                 if (ext4_bg_has_super(sb, grp)) {
3162                         ext4_set_bit(s++, buf);
3163                         count++;
3164                 }
3165                 for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3166                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3167                         count++;
3168                 }
3169         }
3170         if (!count)
3171                 return 0;
3172         return EXT4_CLUSTERS_PER_GROUP(sb) -
3173                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3174 }
3175
3176 /*
3177  * Compute the overhead and stash it in sbi->s_overhead
3178  */
3179 int ext4_calculate_overhead(struct super_block *sb)
3180 {
3181         struct ext4_sb_info *sbi = EXT4_SB(sb);
3182         struct ext4_super_block *es = sbi->s_es;
3183         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3184         ext4_fsblk_t overhead = 0;
3185         char *buf = (char *) get_zeroed_page(GFP_KERNEL);
3186
3187         memset(buf, 0, PAGE_SIZE);
3188         if (!buf)
3189                 return -ENOMEM;
3190
3191         /*
3192          * Compute the overhead (FS structures).  This is constant
3193          * for a given filesystem unless the number of block groups
3194          * changes so we cache the previous value until it does.
3195          */
3196
3197         /*
3198          * All of the blocks before first_data_block are overhead
3199          */
3200         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3201
3202         /*
3203          * Add the overhead found in each block group
3204          */
3205         for (i = 0; i < ngroups; i++) {
3206                 int blks;
3207
3208                 blks = count_overhead(sb, i, buf);
3209                 overhead += blks;
3210                 if (blks)
3211                         memset(buf, 0, PAGE_SIZE);
3212                 cond_resched();
3213         }
3214         sbi->s_overhead = overhead;
3215         smp_wmb();
3216         free_page((unsigned long) buf);
3217         return 0;
3218 }
3219
3220 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3221 {
3222         char *orig_data = kstrdup(data, GFP_KERNEL);
3223         struct buffer_head *bh;
3224         struct ext4_super_block *es = NULL;
3225         struct ext4_sb_info *sbi;
3226         ext4_fsblk_t block;
3227         ext4_fsblk_t sb_block = get_sb_block(&data);
3228         ext4_fsblk_t logical_sb_block;
3229         unsigned long offset = 0;
3230         unsigned long journal_devnum = 0;
3231         unsigned long def_mount_opts;
3232         struct inode *root;
3233         char *cp;
3234         const char *descr;
3235         int ret = -ENOMEM;
3236         int blocksize, clustersize;
3237         unsigned int db_count;
3238         unsigned int i;
3239         int needs_recovery, has_huge_files, has_bigalloc;
3240         __u64 blocks_count;
3241         int err;
3242         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3243         ext4_group_t first_not_zeroed;
3244
3245         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3246         if (!sbi)
3247                 goto out_free_orig;
3248
3249         sbi->s_blockgroup_lock =
3250                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3251         if (!sbi->s_blockgroup_lock) {
3252                 kfree(sbi);
3253                 goto out_free_orig;
3254         }
3255         sb->s_fs_info = sbi;
3256         sbi->s_sb = sb;
3257         sbi->s_mount_opt = 0;
3258         sbi->s_resuid = make_kuid(&init_user_ns, EXT4_DEF_RESUID);
3259         sbi->s_resgid = make_kgid(&init_user_ns, EXT4_DEF_RESGID);
3260         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3261         sbi->s_sb_block = sb_block;
3262         if (sb->s_bdev->bd_part)
3263                 sbi->s_sectors_written_start =
3264                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3265
3266         /* Cleanup superblock name */
3267         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3268                 *cp = '!';
3269
3270         ret = -EINVAL;
3271         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3272         if (!blocksize) {
3273                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3274                 goto out_fail;
3275         }
3276
3277         /*
3278          * The ext4 superblock will not be buffer aligned for other than 1kB
3279          * block sizes.  We need to calculate the offset from buffer start.
3280          */
3281         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3282                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3283                 offset = do_div(logical_sb_block, blocksize);
3284         } else {
3285                 logical_sb_block = sb_block;
3286         }
3287
3288         if (!(bh = sb_bread(sb, logical_sb_block))) {
3289                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3290                 goto out_fail;
3291         }
3292         /*
3293          * Note: s_es must be initialized as soon as possible because
3294          *       some ext4 macro-instructions depend on its value
3295          */
3296         es = (struct ext4_super_block *) (bh->b_data + offset);
3297         sbi->s_es = es;
3298         sb->s_magic = le16_to_cpu(es->s_magic);
3299         if (sb->s_magic != EXT4_SUPER_MAGIC)
3300                 goto cantfind_ext4;
3301         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3302
3303         /* Warn if metadata_csum and gdt_csum are both set. */
3304         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3305                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
3306             EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
3307                 ext4_warning(sb, KERN_INFO "metadata_csum and uninit_bg are "
3308                              "redundant flags; please run fsck.");
3309
3310         /* Check for a known checksum algorithm */
3311         if (!ext4_verify_csum_type(sb, es)) {
3312                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3313                          "unknown checksum algorithm.");
3314                 silent = 1;
3315                 goto cantfind_ext4;
3316         }
3317
3318         /* Load the checksum driver */
3319         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3320                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3321                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3322                 if (IS_ERR(sbi->s_chksum_driver)) {
3323                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3324                         ret = PTR_ERR(sbi->s_chksum_driver);
3325                         sbi->s_chksum_driver = NULL;
3326                         goto failed_mount;
3327                 }
3328         }
3329
3330         /* Check superblock checksum */
3331         if (!ext4_superblock_csum_verify(sb, es)) {
3332                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3333                          "invalid superblock checksum.  Run e2fsck?");
3334                 silent = 1;
3335                 goto cantfind_ext4;
3336         }
3337
3338         /* Precompute checksum seed for all metadata */
3339         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3340                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
3341                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3342                                                sizeof(es->s_uuid));
3343
3344         /* Set defaults before we parse the mount options */
3345         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3346         set_opt(sb, INIT_INODE_TABLE);
3347         if (def_mount_opts & EXT4_DEFM_DEBUG)
3348                 set_opt(sb, DEBUG);
3349         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3350                 set_opt(sb, GRPID);
3351         if (def_mount_opts & EXT4_DEFM_UID16)
3352                 set_opt(sb, NO_UID32);
3353         /* xattr user namespace & acls are now defaulted on */
3354 #ifdef CONFIG_EXT4_FS_XATTR
3355         set_opt(sb, XATTR_USER);
3356 #endif
3357 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3358         set_opt(sb, POSIX_ACL);
3359 #endif
3360         set_opt(sb, MBLK_IO_SUBMIT);
3361         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3362                 set_opt(sb, JOURNAL_DATA);
3363         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3364                 set_opt(sb, ORDERED_DATA);
3365         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3366                 set_opt(sb, WRITEBACK_DATA);
3367
3368         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3369                 set_opt(sb, ERRORS_PANIC);
3370         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3371                 set_opt(sb, ERRORS_CONT);
3372         else
3373                 set_opt(sb, ERRORS_RO);
3374         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3375                 set_opt(sb, BLOCK_VALIDITY);
3376         if (def_mount_opts & EXT4_DEFM_DISCARD)
3377                 set_opt(sb, DISCARD);
3378
3379         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3380         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3381         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3382         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3383         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3384
3385         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3386                 set_opt(sb, BARRIER);
3387
3388         /*
3389          * enable delayed allocation by default
3390          * Use -o nodelalloc to turn it off
3391          */
3392         if (!IS_EXT3_SB(sb) &&
3393             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3394                 set_opt(sb, DELALLOC);
3395
3396         /*
3397          * set default s_li_wait_mult for lazyinit, for the case there is
3398          * no mount option specified.
3399          */
3400         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3401
3402         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3403                            &journal_devnum, &journal_ioprio, 0)) {
3404                 ext4_msg(sb, KERN_WARNING,
3405                          "failed to parse options in superblock: %s",
3406                          sbi->s_es->s_mount_opts);
3407         }
3408         sbi->s_def_mount_opt = sbi->s_mount_opt;
3409         if (!parse_options((char *) data, sb, &journal_devnum,
3410                            &journal_ioprio, 0))
3411                 goto failed_mount;
3412
3413         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3414                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3415                             "with data=journal disables delayed "
3416                             "allocation and O_DIRECT support!\n");
3417                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3418                         ext4_msg(sb, KERN_ERR, "can't mount with "
3419                                  "both data=journal and delalloc");
3420                         goto failed_mount;
3421                 }
3422                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3423                         ext4_msg(sb, KERN_ERR, "can't mount with "
3424                                  "both data=journal and delalloc");
3425                         goto failed_mount;
3426                 }
3427                 if (test_opt(sb, DELALLOC))
3428                         clear_opt(sb, DELALLOC);
3429         }
3430
3431         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3432         if (test_opt(sb, DIOREAD_NOLOCK)) {
3433                 if (blocksize < PAGE_SIZE) {
3434                         ext4_msg(sb, KERN_ERR, "can't mount with "
3435                                  "dioread_nolock if block size != PAGE_SIZE");
3436                         goto failed_mount;
3437                 }
3438         }
3439
3440         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3441                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3442
3443         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3444             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3445              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3446              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3447                 ext4_msg(sb, KERN_WARNING,
3448                        "feature flags set on rev 0 fs, "
3449                        "running e2fsck is recommended");
3450
3451         if (IS_EXT2_SB(sb)) {
3452                 if (ext2_feature_set_ok(sb))
3453                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3454                                  "using the ext4 subsystem");
3455                 else {
3456                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3457                                  "to feature incompatibilities");
3458                         goto failed_mount;
3459                 }
3460         }
3461
3462         if (IS_EXT3_SB(sb)) {
3463                 if (ext3_feature_set_ok(sb))
3464                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3465                                  "using the ext4 subsystem");
3466                 else {
3467                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3468                                  "to feature incompatibilities");
3469                         goto failed_mount;
3470                 }
3471         }
3472
3473         /*
3474          * Check feature flags regardless of the revision level, since we
3475          * previously didn't change the revision level when setting the flags,
3476          * so there is a chance incompat flags are set on a rev 0 filesystem.
3477          */
3478         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3479                 goto failed_mount;
3480
3481         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3482             blocksize > EXT4_MAX_BLOCK_SIZE) {
3483                 ext4_msg(sb, KERN_ERR,
3484                        "Unsupported filesystem blocksize %d", blocksize);
3485                 goto failed_mount;
3486         }
3487
3488         if (sb->s_blocksize != blocksize) {
3489                 /* Validate the filesystem blocksize */
3490                 if (!sb_set_blocksize(sb, blocksize)) {
3491                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3492                                         blocksize);
3493                         goto failed_mount;
3494                 }
3495
3496                 brelse(bh);
3497                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3498                 offset = do_div(logical_sb_block, blocksize);
3499                 bh = sb_bread(sb, logical_sb_block);
3500                 if (!bh) {
3501                         ext4_msg(sb, KERN_ERR,
3502                                "Can't read superblock on 2nd try");
3503                         goto failed_mount;
3504                 }
3505                 es = (struct ext4_super_block *)(bh->b_data + offset);
3506                 sbi->s_es = es;
3507                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3508                         ext4_msg(sb, KERN_ERR,
3509                                "Magic mismatch, very weird!");
3510                         goto failed_mount;
3511                 }
3512         }
3513
3514         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3515                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3516         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3517                                                       has_huge_files);
3518         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3519
3520         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3521                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3522                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3523         } else {
3524                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3525                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3526                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3527                     (!is_power_of_2(sbi->s_inode_size)) ||
3528                     (sbi->s_inode_size > blocksize)) {
3529                         ext4_msg(sb, KERN_ERR,
3530                                "unsupported inode size: %d",
3531                                sbi->s_inode_size);
3532                         goto failed_mount;
3533                 }
3534                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3535                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3536         }
3537
3538         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3539         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3540                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3541                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3542                     !is_power_of_2(sbi->s_desc_size)) {
3543                         ext4_msg(sb, KERN_ERR,
3544                                "unsupported descriptor size %lu",
3545                                sbi->s_desc_size);
3546                         goto failed_mount;
3547                 }
3548         } else
3549                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3550
3551         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3552         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3553         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3554                 goto cantfind_ext4;
3555
3556         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3557         if (sbi->s_inodes_per_block == 0)
3558                 goto cantfind_ext4;
3559         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3560                                         sbi->s_inodes_per_block;
3561         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3562         sbi->s_sbh = bh;
3563         sbi->s_mount_state = le16_to_cpu(es->s_state);
3564         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3565         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3566
3567         for (i = 0; i < 4; i++)
3568                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3569         sbi->s_def_hash_version = es->s_def_hash_version;
3570         i = le32_to_cpu(es->s_flags);
3571         if (i & EXT2_FLAGS_UNSIGNED_HASH)
3572                 sbi->s_hash_unsigned = 3;
3573         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3574 #ifdef __CHAR_UNSIGNED__
3575                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3576                 sbi->s_hash_unsigned = 3;
3577 #else
3578                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3579 #endif
3580         }
3581
3582         /* Handle clustersize */
3583         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3584         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3585                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3586         if (has_bigalloc) {
3587                 if (clustersize < blocksize) {
3588                         ext4_msg(sb, KERN_ERR,
3589                                  "cluster size (%d) smaller than "
3590                                  "block size (%d)", clustersize, blocksize);
3591                         goto failed_mount;
3592                 }
3593                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3594                         le32_to_cpu(es->s_log_block_size);
3595                 sbi->s_clusters_per_group =
3596                         le32_to_cpu(es->s_clusters_per_group);
3597                 if (sbi->s_clusters_per_group > blocksize * 8) {
3598                         ext4_msg(sb, KERN_ERR,
3599                                  "#clusters per group too big: %lu",
3600                                  sbi->s_clusters_per_group);
3601                         goto failed_mount;
3602                 }
3603                 if (sbi->s_blocks_per_group !=
3604                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3605                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3606                                  "clusters per group (%lu) inconsistent",
3607                                  sbi->s_blocks_per_group,
3608                                  sbi->s_clusters_per_group);
3609                         goto failed_mount;
3610                 }
3611         } else {
3612                 if (clustersize != blocksize) {
3613                         ext4_warning(sb, "fragment/cluster size (%d) != "
3614                                      "block size (%d)", clustersize,
3615                                      blocksize);
3616                         clustersize = blocksize;
3617                 }
3618                 if (sbi->s_blocks_per_group > blocksize * 8) {
3619                         ext4_msg(sb, KERN_ERR,
3620                                  "#blocks per group too big: %lu",
3621                                  sbi->s_blocks_per_group);
3622                         goto failed_mount;
3623                 }
3624                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3625                 sbi->s_cluster_bits = 0;
3626         }
3627         sbi->s_cluster_ratio = clustersize / blocksize;
3628
3629         if (sbi->s_inodes_per_group > blocksize * 8) {
3630                 ext4_msg(sb, KERN_ERR,
3631                        "#inodes per group too big: %lu",
3632                        sbi->s_inodes_per_group);
3633                 goto failed_mount;
3634         }
3635
3636         /*
3637          * Test whether we have more sectors than will fit in sector_t,
3638          * and whether the max offset is addressable by the page cache.
3639          */
3640         err = generic_check_addressable(sb->s_blocksize_bits,
3641                                         ext4_blocks_count(es));
3642         if (err) {
3643                 ext4_msg(sb, KERN_ERR, "filesystem"
3644                          " too large to mount safely on this system");
3645                 if (sizeof(sector_t) < 8)
3646                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3647                 ret = err;
3648                 goto failed_mount;
3649         }
3650
3651         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3652                 goto cantfind_ext4;
3653
3654         /* check blocks count against device size */
3655         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3656         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3657                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3658                        "exceeds size of device (%llu blocks)",
3659                        ext4_blocks_count(es), blocks_count);
3660                 goto failed_mount;
3661         }
3662
3663         /*
3664          * It makes no sense for the first data block to be beyond the end
3665          * of the filesystem.
3666          */
3667         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3668                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3669                          "block %u is beyond end of filesystem (%llu)",
3670                          le32_to_cpu(es->s_first_data_block),
3671                          ext4_blocks_count(es));
3672                 goto failed_mount;
3673         }
3674         blocks_count = (ext4_blocks_count(es) -
3675                         le32_to_cpu(es->s_first_data_block) +
3676                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3677         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3678         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3679                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3680                        "(block count %llu, first data block %u, "
3681                        "blocks per group %lu)", sbi->s_groups_count,
3682                        ext4_blocks_count(es),
3683                        le32_to_cpu(es->s_first_data_block),
3684                        EXT4_BLOCKS_PER_GROUP(sb));
3685                 goto failed_mount;
3686         }
3687         sbi->s_groups_count = blocks_count;
3688         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3689                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3690         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3691                    EXT4_DESC_PER_BLOCK(sb);
3692         sbi->s_group_desc = ext4_kvmalloc(db_count *
3693                                           sizeof(struct buffer_head *),
3694                                           GFP_KERNEL);
3695         if (sbi->s_group_desc == NULL) {
3696                 ext4_msg(sb, KERN_ERR, "not enough memory");
3697                 ret = -ENOMEM;
3698                 goto failed_mount;
3699         }
3700
3701         if (ext4_proc_root)
3702                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3703
3704         if (sbi->s_proc)
3705                 proc_create_data("options", S_IRUGO, sbi->s_proc,
3706                                  &ext4_seq_options_fops, sb);
3707
3708         bgl_lock_init(sbi->s_blockgroup_lock);
3709
3710         for (i = 0; i < db_count; i++) {
3711                 block = descriptor_loc(sb, logical_sb_block, i);
3712                 sbi->s_group_desc[i] = sb_bread(sb, block);
3713                 if (!sbi->s_group_desc[i]) {
3714                         ext4_msg(sb, KERN_ERR,
3715                                "can't read group descriptor %d", i);
3716                         db_count = i;
3717                         goto failed_mount2;
3718                 }
3719         }
3720         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3721                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3722                 goto failed_mount2;
3723         }
3724         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3725                 if (!ext4_fill_flex_info(sb)) {
3726                         ext4_msg(sb, KERN_ERR,
3727                                "unable to initialize "
3728                                "flex_bg meta info!");
3729                         goto failed_mount2;
3730                 }
3731
3732         sbi->s_gdb_count = db_count;
3733         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3734         spin_lock_init(&sbi->s_next_gen_lock);
3735
3736         init_timer(&sbi->s_err_report);
3737         sbi->s_err_report.function = print_daily_error_info;
3738         sbi->s_err_report.data = (unsigned long) sb;
3739
3740         err = percpu_counter_init(&sbi->s_freeclusters_counter,
3741                         ext4_count_free_clusters(sb));
3742         if (!err) {
3743                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
3744                                 ext4_count_free_inodes(sb));
3745         }
3746         if (!err) {
3747                 err = percpu_counter_init(&sbi->s_dirs_counter,
3748                                 ext4_count_dirs(sb));
3749         }
3750         if (!err) {
3751                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0);
3752         }
3753         if (err) {
3754                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3755                 ret = err;
3756                 goto failed_mount3;
3757         }
3758
3759         sbi->s_stripe = ext4_get_stripe_size(sbi);
3760         sbi->s_max_writeback_mb_bump = 128;
3761
3762         /*
3763          * set up enough so that it can read an inode
3764          */
3765         if (!test_opt(sb, NOLOAD) &&
3766             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3767                 sb->s_op = &ext4_sops;
3768         else
3769                 sb->s_op = &ext4_nojournal_sops;
3770         sb->s_export_op = &ext4_export_ops;
3771         sb->s_xattr = ext4_xattr_handlers;
3772 #ifdef CONFIG_QUOTA
3773         sb->s_qcop = &ext4_qctl_operations;
3774         sb->dq_op = &ext4_quota_operations;
3775
3776         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) {
3777                 /* Use qctl operations for hidden quota files. */
3778                 sb->s_qcop = &ext4_qctl_sysfile_operations;
3779         }
3780 #endif
3781         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3782
3783         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3784         mutex_init(&sbi->s_orphan_lock);
3785         sbi->s_resize_flags = 0;
3786
3787         sb->s_root = NULL;
3788
3789         needs_recovery = (es->s_last_orphan != 0 ||
3790                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3791                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3792
3793         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3794             !(sb->s_flags & MS_RDONLY))
3795                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3796                         goto failed_mount3;
3797
3798         /*
3799          * The first inode we look at is the journal inode.  Don't try
3800          * root first: it may be modified in the journal!
3801          */
3802         if (!test_opt(sb, NOLOAD) &&
3803             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3804                 if (ext4_load_journal(sb, es, journal_devnum))
3805                         goto failed_mount3;
3806         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3807               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3808                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3809                        "suppressed and not mounted read-only");
3810                 goto failed_mount_wq;
3811         } else {
3812                 clear_opt(sb, DATA_FLAGS);
3813                 sbi->s_journal = NULL;
3814                 needs_recovery = 0;
3815                 goto no_journal;
3816         }
3817
3818         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) &&
3819             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3820                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3821                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3822                 goto failed_mount_wq;
3823         }
3824
3825         if (!set_journal_csum_feature_set(sb)) {
3826                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
3827                          "feature set");
3828                 goto failed_mount_wq;
3829         }
3830
3831         /* We have now updated the journal if required, so we can
3832          * validate the data journaling mode. */
3833         switch (test_opt(sb, DATA_FLAGS)) {
3834         case 0:
3835                 /* No mode set, assume a default based on the journal
3836                  * capabilities: ORDERED_DATA if the journal can
3837                  * cope, else JOURNAL_DATA
3838                  */
3839                 if (jbd2_journal_check_available_features
3840                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3841                         set_opt(sb, ORDERED_DATA);
3842                 else
3843                         set_opt(sb, JOURNAL_DATA);
3844                 break;
3845
3846         case EXT4_MOUNT_ORDERED_DATA:
3847         case EXT4_MOUNT_WRITEBACK_DATA:
3848                 if (!jbd2_journal_check_available_features
3849                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3850                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3851                                "requested data journaling mode");
3852                         goto failed_mount_wq;
3853                 }
3854         default:
3855                 break;
3856         }
3857         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3858
3859         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
3860
3861         /*
3862          * The journal may have updated the bg summary counts, so we
3863          * need to update the global counters.
3864          */
3865         percpu_counter_set(&sbi->s_freeclusters_counter,
3866                            ext4_count_free_clusters(sb));
3867         percpu_counter_set(&sbi->s_freeinodes_counter,
3868                            ext4_count_free_inodes(sb));
3869         percpu_counter_set(&sbi->s_dirs_counter,
3870                            ext4_count_dirs(sb));
3871         percpu_counter_set(&sbi->s_dirtyclusters_counter, 0);
3872
3873 no_journal:
3874         /*
3875          * Get the # of file system overhead blocks from the
3876          * superblock if present.
3877          */
3878         if (es->s_overhead_clusters)
3879                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
3880         else {
3881                 ret = ext4_calculate_overhead(sb);
3882                 if (ret)
3883                         goto failed_mount_wq;
3884         }
3885
3886         /*
3887          * The maximum number of concurrent works can be high and
3888          * concurrency isn't really necessary.  Limit it to 1.
3889          */
3890         EXT4_SB(sb)->dio_unwritten_wq =
3891                 alloc_workqueue("ext4-dio-unwritten", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
3892         if (!EXT4_SB(sb)->dio_unwritten_wq) {
3893                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
3894                 goto failed_mount_wq;
3895         }
3896
3897         /*
3898          * The jbd2_journal_load will have done any necessary log recovery,
3899          * so we can safely mount the rest of the filesystem now.
3900          */
3901
3902         root = ext4_iget(sb, EXT4_ROOT_INO);
3903         if (IS_ERR(root)) {
3904                 ext4_msg(sb, KERN_ERR, "get root inode failed");
3905                 ret = PTR_ERR(root);
3906                 root = NULL;
3907                 goto failed_mount4;
3908         }
3909         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3910                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3911                 iput(root);
3912                 goto failed_mount4;
3913         }
3914         sb->s_root = d_make_root(root);
3915         if (!sb->s_root) {
3916                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
3917                 ret = -ENOMEM;
3918                 goto failed_mount4;
3919         }
3920
3921         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
3922                 sb->s_flags |= MS_RDONLY;
3923
3924         /* determine the minimum size of new large inodes, if present */
3925         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3926                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3927                                                      EXT4_GOOD_OLD_INODE_SIZE;
3928                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3929                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
3930                         if (sbi->s_want_extra_isize <
3931                             le16_to_cpu(es->s_want_extra_isize))
3932                                 sbi->s_want_extra_isize =
3933                                         le16_to_cpu(es->s_want_extra_isize);
3934                         if (sbi->s_want_extra_isize <
3935                             le16_to_cpu(es->s_min_extra_isize))
3936                                 sbi->s_want_extra_isize =
3937                                         le16_to_cpu(es->s_min_extra_isize);
3938                 }
3939         }
3940         /* Check if enough inode space is available */
3941         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3942                                                         sbi->s_inode_size) {
3943                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3944                                                        EXT4_GOOD_OLD_INODE_SIZE;
3945                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
3946                          "available");
3947         }
3948
3949         err = ext4_setup_system_zone(sb);
3950         if (err) {
3951                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3952                          "zone (%d)", err);
3953                 goto failed_mount4a;
3954         }
3955
3956         ext4_ext_init(sb);
3957         err = ext4_mb_init(sb);
3958         if (err) {
3959                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3960                          err);
3961                 goto failed_mount5;
3962         }
3963
3964         err = ext4_register_li_request(sb, first_not_zeroed);
3965         if (err)
3966                 goto failed_mount6;
3967
3968         sbi->s_kobj.kset = ext4_kset;
3969         init_completion(&sbi->s_kobj_unregister);
3970         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3971                                    "%s", sb->s_id);
3972         if (err)
3973                 goto failed_mount7;
3974
3975         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3976         ext4_orphan_cleanup(sb, es);
3977         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3978         if (needs_recovery) {
3979                 ext4_msg(sb, KERN_INFO, "recovery complete");
3980                 ext4_mark_recovery_complete(sb, es);
3981         }
3982         if (EXT4_SB(sb)->s_journal) {
3983                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3984                         descr = " journalled data mode";
3985                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3986                         descr = " ordered data mode";
3987                 else
3988                         descr = " writeback data mode";
3989         } else
3990                 descr = "out journal";
3991
3992 #ifdef CONFIG_QUOTA
3993         /* Enable quota usage during mount. */
3994         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
3995             !(sb->s_flags & MS_RDONLY)) {
3996                 ret = ext4_enable_quotas(sb);
3997                 if (ret)
3998                         goto failed_mount7;
3999         }
4000 #endif  /* CONFIG_QUOTA */
4001
4002         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4003                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
4004                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4005
4006         if (es->s_error_count)
4007                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4008
4009         kfree(orig_data);
4010         return 0;
4011
4012 cantfind_ext4:
4013         if (!silent)
4014                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4015         goto failed_mount;
4016
4017 failed_mount7:
4018         ext4_unregister_li_request(sb);
4019 failed_mount6:
4020         ext4_mb_release(sb);
4021 failed_mount5:
4022         ext4_ext_release(sb);
4023         ext4_release_system_zone(sb);
4024 failed_mount4a:
4025         dput(sb->s_root);
4026         sb->s_root = NULL;
4027 failed_mount4:
4028         ext4_msg(sb, KERN_ERR, "mount failed");
4029         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
4030 failed_mount_wq:
4031         if (sbi->s_journal) {
4032                 jbd2_journal_destroy(sbi->s_journal);
4033                 sbi->s_journal = NULL;
4034         }
4035 failed_mount3:
4036         del_timer(&sbi->s_err_report);
4037         if (sbi->s_flex_groups)
4038                 ext4_kvfree(sbi->s_flex_groups);
4039         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4040         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4041         percpu_counter_destroy(&sbi->s_dirs_counter);
4042         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4043         if (sbi->s_mmp_tsk)
4044                 kthread_stop(sbi->s_mmp_tsk);
4045 failed_mount2:
4046         for (i = 0; i < db_count; i++)
4047                 brelse(sbi->s_group_desc[i]);
4048         ext4_kvfree(sbi->s_group_desc);
4049 failed_mount:
4050         if (sbi->s_chksum_driver)
4051                 crypto_free_shash(sbi->s_chksum_driver);
4052         if (sbi->s_proc) {
4053                 remove_proc_entry("options", sbi->s_proc);
4054                 remove_proc_entry(sb->s_id, ext4_proc_root);
4055         }
4056 #ifdef CONFIG_QUOTA
4057         for (i = 0; i < MAXQUOTAS; i++)
4058                 kfree(sbi->s_qf_names[i]);
4059 #endif
4060         ext4_blkdev_remove(sbi);
4061         brelse(bh);
4062 out_fail:
4063         sb->s_fs_info = NULL;
4064         kfree(sbi->s_blockgroup_lock);
4065         kfree(sbi);
4066 out_free_orig:
4067         kfree(orig_data);
4068         return ret;
4069 }
4070
4071 /*
4072  * Setup any per-fs journal parameters now.  We'll do this both on
4073  * initial mount, once the journal has been initialised but before we've
4074  * done any recovery; and again on any subsequent remount.
4075  */
4076 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4077 {
4078         struct ext4_sb_info *sbi = EXT4_SB(sb);
4079
4080         journal->j_commit_interval = sbi->s_commit_interval;
4081         journal->j_min_batch_time = sbi->s_min_batch_time;
4082         journal->j_max_batch_time = sbi->s_max_batch_time;
4083
4084         write_lock(&journal->j_state_lock);
4085         if (test_opt(sb, BARRIER))
4086                 journal->j_flags |= JBD2_BARRIER;
4087         else
4088                 journal->j_flags &= ~JBD2_BARRIER;
4089         if (test_opt(sb, DATA_ERR_ABORT))
4090                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4091         else
4092                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4093         write_unlock(&journal->j_state_lock);
4094 }
4095
4096 static journal_t *ext4_get_journal(struct super_block *sb,
4097                                    unsigned int journal_inum)
4098 {
4099         struct inode *journal_inode;
4100         journal_t *journal;
4101
4102         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4103
4104         /* First, test for the existence of a valid inode on disk.  Bad
4105          * things happen if we iget() an unused inode, as the subsequent
4106          * iput() will try to delete it. */
4107
4108         journal_inode = ext4_iget(sb, journal_inum);
4109         if (IS_ERR(journal_inode)) {
4110                 ext4_msg(sb, KERN_ERR, "no journal found");
4111                 return NULL;
4112         }
4113         if (!journal_inode->i_nlink) {
4114                 make_bad_inode(journal_inode);
4115                 iput(journal_inode);
4116                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4117                 return NULL;
4118         }
4119
4120         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4121                   journal_inode, journal_inode->i_size);
4122         if (!S_ISREG(journal_inode->i_mode)) {
4123                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4124                 iput(journal_inode);
4125                 return NULL;
4126         }
4127
4128         journal = jbd2_journal_init_inode(journal_inode);
4129         if (!journal) {
4130                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4131                 iput(journal_inode);
4132                 return NULL;
4133         }
4134         journal->j_private = sb;
4135         ext4_init_journal_params(sb, journal);
4136         return journal;
4137 }
4138
4139 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4140                                        dev_t j_dev)
4141 {
4142         struct buffer_head *bh;
4143         journal_t *journal;
4144         ext4_fsblk_t start;
4145         ext4_fsblk_t len;
4146         int hblock, blocksize;
4147         ext4_fsblk_t sb_block;
4148         unsigned long offset;
4149         struct ext4_super_block *es;
4150         struct block_device *bdev;
4151
4152         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4153
4154         bdev = ext4_blkdev_get(j_dev, sb);
4155         if (bdev == NULL)
4156                 return NULL;
4157
4158         blocksize = sb->s_blocksize;
4159         hblock = bdev_logical_block_size(bdev);
4160         if (blocksize < hblock) {
4161                 ext4_msg(sb, KERN_ERR,
4162                         "blocksize too small for journal device");
4163                 goto out_bdev;
4164         }
4165
4166         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4167         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4168         set_blocksize(bdev, blocksize);
4169         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4170                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4171                        "external journal");
4172                 goto out_bdev;
4173         }
4174
4175         es = (struct ext4_super_block *) (bh->b_data + offset);
4176         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4177             !(le32_to_cpu(es->s_feature_incompat) &
4178               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4179                 ext4_msg(sb, KERN_ERR, "external journal has "
4180                                         "bad superblock");
4181                 brelse(bh);
4182                 goto out_bdev;
4183         }
4184
4185         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4186                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4187                 brelse(bh);
4188                 goto out_bdev;
4189         }
4190
4191         len = ext4_blocks_count(es);
4192         start = sb_block + 1;
4193         brelse(bh);     /* we're done with the superblock */
4194
4195         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4196                                         start, len, blocksize);
4197         if (!journal) {
4198                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4199                 goto out_bdev;
4200         }
4201         journal->j_private = sb;
4202         ll_rw_block(READ, 1, &journal->j_sb_buffer);
4203         wait_on_buffer(journal->j_sb_buffer);
4204         if (!buffer_uptodate(journal->j_sb_buffer)) {
4205                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4206                 goto out_journal;
4207         }
4208         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4209                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4210                                         "user (unsupported) - %d",
4211                         be32_to_cpu(journal->j_superblock->s_nr_users));
4212                 goto out_journal;
4213         }
4214         EXT4_SB(sb)->journal_bdev = bdev;
4215         ext4_init_journal_params(sb, journal);
4216         return journal;
4217
4218 out_journal:
4219         jbd2_journal_destroy(journal);
4220 out_bdev:
4221         ext4_blkdev_put(bdev);
4222         return NULL;
4223 }
4224
4225 static int ext4_load_journal(struct super_block *sb,
4226                              struct ext4_super_block *es,
4227                              unsigned long journal_devnum)
4228 {
4229         journal_t *journal;
4230         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4231         dev_t journal_dev;
4232         int err = 0;
4233         int really_read_only;
4234
4235         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4236
4237         if (journal_devnum &&
4238             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4239                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4240                         "numbers have changed");
4241                 journal_dev = new_decode_dev(journal_devnum);
4242         } else
4243                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4244
4245         really_read_only = bdev_read_only(sb->s_bdev);
4246
4247         /*
4248          * Are we loading a blank journal or performing recovery after a
4249          * crash?  For recovery, we need to check in advance whether we
4250          * can get read-write access to the device.
4251          */
4252         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4253                 if (sb->s_flags & MS_RDONLY) {
4254                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4255                                         "required on readonly filesystem");
4256                         if (really_read_only) {
4257                                 ext4_msg(sb, KERN_ERR, "write access "
4258                                         "unavailable, cannot proceed");
4259                                 return -EROFS;
4260                         }
4261                         ext4_msg(sb, KERN_INFO, "write access will "
4262                                "be enabled during recovery");
4263                 }
4264         }
4265
4266         if (journal_inum && journal_dev) {
4267                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4268                        "and inode journals!");
4269                 return -EINVAL;
4270         }
4271
4272         if (journal_inum) {
4273                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4274                         return -EINVAL;
4275         } else {
4276                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4277                         return -EINVAL;
4278         }
4279
4280         if (!(journal->j_flags & JBD2_BARRIER))
4281                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4282
4283         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4284                 err = jbd2_journal_wipe(journal, !really_read_only);
4285         if (!err) {
4286                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4287                 if (save)
4288                         memcpy(save, ((char *) es) +
4289                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4290                 err = jbd2_journal_load(journal);
4291                 if (save)
4292                         memcpy(((char *) es) + EXT4_S_ERR_START,
4293                                save, EXT4_S_ERR_LEN);
4294                 kfree(save);
4295         }
4296
4297         if (err) {
4298                 ext4_msg(sb, KERN_ERR, "error loading journal");
4299                 jbd2_journal_destroy(journal);
4300                 return err;
4301         }
4302
4303         EXT4_SB(sb)->s_journal = journal;
4304         ext4_clear_journal_err(sb, es);
4305
4306         if (!really_read_only && journal_devnum &&
4307             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4308                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4309
4310                 /* Make sure we flush the recovery flag to disk. */
4311                 ext4_commit_super(sb, 1);
4312         }
4313
4314         return 0;
4315 }
4316
4317 static int ext4_commit_super(struct super_block *sb, int sync)
4318 {
4319         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4320         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4321         int error = 0;
4322
4323         if (!sbh || block_device_ejected(sb))
4324                 return error;
4325         if (buffer_write_io_error(sbh)) {
4326                 /*
4327                  * Oh, dear.  A previous attempt to write the
4328                  * superblock failed.  This could happen because the
4329                  * USB device was yanked out.  Or it could happen to
4330                  * be a transient write error and maybe the block will
4331                  * be remapped.  Nothing we can do but to retry the
4332                  * write and hope for the best.
4333                  */
4334                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4335                        "superblock detected");
4336                 clear_buffer_write_io_error(sbh);
4337                 set_buffer_uptodate(sbh);
4338         }
4339         /*
4340          * If the file system is mounted read-only, don't update the
4341          * superblock write time.  This avoids updating the superblock
4342          * write time when we are mounting the root file system
4343          * read/only but we need to replay the journal; at that point,
4344          * for people who are east of GMT and who make their clock
4345          * tick in localtime for Windows bug-for-bug compatibility,
4346          * the clock is set in the future, and this will cause e2fsck
4347          * to complain and force a full file system check.
4348          */
4349         if (!(sb->s_flags & MS_RDONLY))
4350                 es->s_wtime = cpu_to_le32(get_seconds());
4351         if (sb->s_bdev->bd_part)
4352                 es->s_kbytes_written =
4353                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4354                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4355                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4356         else
4357                 es->s_kbytes_written =
4358                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4359         ext4_free_blocks_count_set(es,
4360                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4361                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4362         es->s_free_inodes_count =
4363                 cpu_to_le32(percpu_counter_sum_positive(
4364                                 &EXT4_SB(sb)->s_freeinodes_counter));
4365         BUFFER_TRACE(sbh, "marking dirty");
4366         ext4_superblock_csum_set(sb, es);
4367         mark_buffer_dirty(sbh);
4368         if (sync) {
4369                 error = sync_dirty_buffer(sbh);
4370                 if (error)
4371                         return error;
4372
4373                 error = buffer_write_io_error(sbh);
4374                 if (error) {
4375                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4376                                "superblock");
4377                         clear_buffer_write_io_error(sbh);
4378                         set_buffer_uptodate(sbh);
4379                 }
4380         }
4381         return error;
4382 }
4383
4384 /*
4385  * Have we just finished recovery?  If so, and if we are mounting (or
4386  * remounting) the filesystem readonly, then we will end up with a
4387  * consistent fs on disk.  Record that fact.
4388  */
4389 static void ext4_mark_recovery_complete(struct super_block *sb,
4390                                         struct ext4_super_block *es)
4391 {
4392         journal_t *journal = EXT4_SB(sb)->s_journal;
4393
4394         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4395                 BUG_ON(journal != NULL);
4396                 return;
4397         }
4398         jbd2_journal_lock_updates(journal);
4399         if (jbd2_journal_flush(journal) < 0)
4400                 goto out;
4401
4402         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4403             sb->s_flags & MS_RDONLY) {
4404                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4405                 ext4_commit_super(sb, 1);
4406         }
4407
4408 out:
4409         jbd2_journal_unlock_updates(journal);
4410 }
4411
4412 /*
4413  * If we are mounting (or read-write remounting) a filesystem whose journal
4414  * has recorded an error from a previous lifetime, move that error to the
4415  * main filesystem now.
4416  */
4417 static void ext4_clear_journal_err(struct super_block *sb,
4418                                    struct ext4_super_block *es)
4419 {
4420         journal_t *journal;
4421         int j_errno;
4422         const char *errstr;
4423
4424         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4425
4426         journal = EXT4_SB(sb)->s_journal;
4427
4428         /*
4429          * Now check for any error status which may have been recorded in the
4430          * journal by a prior ext4_error() or ext4_abort()
4431          */
4432
4433         j_errno = jbd2_journal_errno(journal);
4434         if (j_errno) {
4435                 char nbuf[16];
4436
4437                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4438                 ext4_warning(sb, "Filesystem error recorded "
4439                              "from previous mount: %s", errstr);
4440                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4441
4442                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4443                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4444                 ext4_commit_super(sb, 1);
4445
4446                 jbd2_journal_clear_err(journal);
4447         }
4448 }
4449
4450 /*
4451  * Force the running and committing transactions to commit,
4452  * and wait on the commit.
4453  */
4454 int ext4_force_commit(struct super_block *sb)
4455 {
4456         journal_t *journal;
4457         int ret = 0;
4458
4459         if (sb->s_flags & MS_RDONLY)
4460                 return 0;
4461
4462         journal = EXT4_SB(sb)->s_journal;
4463         if (journal) {
4464                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
4465                 ret = ext4_journal_force_commit(journal);
4466         }
4467
4468         return ret;
4469 }
4470
4471 static int ext4_sync_fs(struct super_block *sb, int wait)
4472 {
4473         int ret = 0;
4474         tid_t target;
4475         struct ext4_sb_info *sbi = EXT4_SB(sb);
4476
4477         trace_ext4_sync_fs(sb, wait);
4478         flush_workqueue(sbi->dio_unwritten_wq);
4479         /*
4480          * Writeback quota in non-journalled quota case - journalled quota has
4481          * no dirty dquots
4482          */
4483         dquot_writeback_dquots(sb, -1);
4484         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4485                 if (wait)
4486                         jbd2_log_wait_commit(sbi->s_journal, target);
4487         }
4488         return ret;
4489 }
4490
4491 /*
4492  * LVM calls this function before a (read-only) snapshot is created.  This
4493  * gives us a chance to flush the journal completely and mark the fs clean.
4494  *
4495  * Note that only this function cannot bring a filesystem to be in a clean
4496  * state independently, because ext4 prevents a new handle from being started
4497  * by @sb->s_frozen, which stays in an upper layer.  It thus needs help from
4498  * the upper layer.
4499  */
4500 static int ext4_freeze(struct super_block *sb)
4501 {
4502         int error = 0;
4503         journal_t *journal;
4504
4505         if (sb->s_flags & MS_RDONLY)
4506                 return 0;
4507
4508         journal = EXT4_SB(sb)->s_journal;
4509
4510         /* Now we set up the journal barrier. */
4511         jbd2_journal_lock_updates(journal);
4512
4513         /*
4514          * Don't clear the needs_recovery flag if we failed to flush
4515          * the journal.
4516          */
4517         error = jbd2_journal_flush(journal);
4518         if (error < 0)
4519                 goto out;
4520
4521         /* Journal blocked and flushed, clear needs_recovery flag. */
4522         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4523         error = ext4_commit_super(sb, 1);
4524 out:
4525         /* we rely on s_frozen to stop further updates */
4526         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4527         return error;
4528 }
4529
4530 /*
4531  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4532  * flag here, even though the filesystem is not technically dirty yet.
4533  */
4534 static int ext4_unfreeze(struct super_block *sb)
4535 {
4536         if (sb->s_flags & MS_RDONLY)
4537                 return 0;
4538
4539         lock_super(sb);
4540         /* Reset the needs_recovery flag before the fs is unlocked. */
4541         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4542         ext4_commit_super(sb, 1);
4543         unlock_super(sb);
4544         return 0;
4545 }
4546
4547 /*
4548  * Structure to save mount options for ext4_remount's benefit
4549  */
4550 struct ext4_mount_options {
4551         unsigned long s_mount_opt;
4552         unsigned long s_mount_opt2;
4553         kuid_t s_resuid;
4554         kgid_t s_resgid;
4555         unsigned long s_commit_interval;
4556         u32 s_min_batch_time, s_max_batch_time;
4557 #ifdef CONFIG_QUOTA
4558         int s_jquota_fmt;
4559         char *s_qf_names[MAXQUOTAS];
4560 #endif
4561 };
4562
4563 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4564 {
4565         struct ext4_super_block *es;
4566         struct ext4_sb_info *sbi = EXT4_SB(sb);
4567         unsigned long old_sb_flags;
4568         struct ext4_mount_options old_opts;
4569         int enable_quota = 0;
4570         ext4_group_t g;
4571         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4572         int err = 0;
4573 #ifdef CONFIG_QUOTA
4574         int i;
4575 #endif
4576         char *orig_data = kstrdup(data, GFP_KERNEL);
4577
4578         /* Store the original options */
4579         lock_super(sb);
4580         old_sb_flags = sb->s_flags;
4581         old_opts.s_mount_opt = sbi->s_mount_opt;
4582         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4583         old_opts.s_resuid = sbi->s_resuid;
4584         old_opts.s_resgid = sbi->s_resgid;
4585         old_opts.s_commit_interval = sbi->s_commit_interval;
4586         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4587         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4588 #ifdef CONFIG_QUOTA
4589         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4590         for (i = 0; i < MAXQUOTAS; i++)
4591                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
4592 #endif
4593         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4594                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4595
4596         /*
4597          * Allow the "check" option to be passed as a remount option.
4598          */
4599         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4600                 err = -EINVAL;
4601                 goto restore_opts;
4602         }
4603
4604         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4605                 ext4_abort(sb, "Abort forced by user");
4606
4607         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4608                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4609
4610         es = sbi->s_es;
4611
4612         if (sbi->s_journal) {
4613                 ext4_init_journal_params(sb, sbi->s_journal);
4614                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4615         }
4616
4617         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4618                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4619                         err = -EROFS;
4620                         goto restore_opts;
4621                 }
4622
4623                 if (*flags & MS_RDONLY) {
4624                         err = dquot_suspend(sb, -1);
4625                         if (err < 0)
4626                                 goto restore_opts;
4627
4628                         /*
4629                          * First of all, the unconditional stuff we have to do
4630                          * to disable replay of the journal when we next remount
4631                          */
4632                         sb->s_flags |= MS_RDONLY;
4633
4634                         /*
4635                          * OK, test if we are remounting a valid rw partition
4636                          * readonly, and if so set the rdonly flag and then
4637                          * mark the partition as valid again.
4638                          */
4639                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4640                             (sbi->s_mount_state & EXT4_VALID_FS))
4641                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4642
4643                         if (sbi->s_journal)
4644                                 ext4_mark_recovery_complete(sb, es);
4645                 } else {
4646                         /* Make sure we can mount this feature set readwrite */
4647                         if (!ext4_feature_set_ok(sb, 0)) {
4648                                 err = -EROFS;
4649                                 goto restore_opts;
4650                         }
4651                         /*
4652                          * Make sure the group descriptor checksums
4653                          * are sane.  If they aren't, refuse to remount r/w.
4654                          */
4655                         for (g = 0; g < sbi->s_groups_count; g++) {
4656                                 struct ext4_group_desc *gdp =
4657                                         ext4_get_group_desc(sb, g, NULL);
4658
4659                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
4660                                         ext4_msg(sb, KERN_ERR,
4661                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4662                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4663                                                le16_to_cpu(gdp->bg_checksum));
4664                                         err = -EINVAL;
4665                                         goto restore_opts;
4666                                 }
4667                         }
4668
4669                         /*
4670                          * If we have an unprocessed orphan list hanging
4671                          * around from a previously readonly bdev mount,
4672                          * require a full umount/remount for now.
4673                          */
4674                         if (es->s_last_orphan) {
4675                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4676                                        "remount RDWR because of unprocessed "
4677                                        "orphan inode list.  Please "
4678                                        "umount/remount instead");
4679                                 err = -EINVAL;
4680                                 goto restore_opts;
4681                         }
4682
4683                         /*
4684                          * Mounting a RDONLY partition read-write, so reread
4685                          * and store the current valid flag.  (It may have
4686                          * been changed by e2fsck since we originally mounted
4687                          * the partition.)
4688                          */
4689                         if (sbi->s_journal)
4690                                 ext4_clear_journal_err(sb, es);
4691                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4692                         if (!ext4_setup_super(sb, es, 0))
4693                                 sb->s_flags &= ~MS_RDONLY;
4694                         if (EXT4_HAS_INCOMPAT_FEATURE(sb,
4695                                                      EXT4_FEATURE_INCOMPAT_MMP))
4696                                 if (ext4_multi_mount_protect(sb,
4697                                                 le64_to_cpu(es->s_mmp_block))) {
4698                                         err = -EROFS;
4699                                         goto restore_opts;
4700                                 }
4701                         enable_quota = 1;
4702                 }
4703         }
4704
4705         /*
4706          * Reinitialize lazy itable initialization thread based on
4707          * current settings
4708          */
4709         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4710                 ext4_unregister_li_request(sb);
4711         else {
4712                 ext4_group_t first_not_zeroed;
4713                 first_not_zeroed = ext4_has_uninit_itable(sb);
4714                 ext4_register_li_request(sb, first_not_zeroed);
4715         }
4716
4717         ext4_setup_system_zone(sb);
4718         if (sbi->s_journal == NULL)
4719                 ext4_commit_super(sb, 1);
4720
4721         unlock_super(sb);
4722 #ifdef CONFIG_QUOTA
4723         /* Release old quota file names */
4724         for (i = 0; i < MAXQUOTAS; i++)
4725                 if (old_opts.s_qf_names[i] &&
4726                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4727                         kfree(old_opts.s_qf_names[i]);
4728         if (enable_quota) {
4729                 if (sb_any_quota_suspended(sb))
4730                         dquot_resume(sb, -1);
4731                 else if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
4732                                         EXT4_FEATURE_RO_COMPAT_QUOTA)) {
4733                         err = ext4_enable_quotas(sb);
4734                         if (err) {
4735                                 lock_super(sb);
4736                                 goto restore_opts;
4737                         }
4738                 }
4739         }
4740 #endif
4741
4742         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4743         kfree(orig_data);
4744         return 0;
4745
4746 restore_opts:
4747         sb->s_flags = old_sb_flags;
4748         sbi->s_mount_opt = old_opts.s_mount_opt;
4749         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4750         sbi->s_resuid = old_opts.s_resuid;
4751         sbi->s_resgid = old_opts.s_resgid;
4752         sbi->s_commit_interval = old_opts.s_commit_interval;
4753         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4754         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4755 #ifdef CONFIG_QUOTA
4756         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4757         for (i = 0; i < MAXQUOTAS; i++) {
4758                 if (sbi->s_qf_names[i] &&
4759                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
4760                         kfree(sbi->s_qf_names[i]);
4761                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4762         }
4763 #endif
4764         unlock_super(sb);
4765         kfree(orig_data);
4766         return err;
4767 }
4768
4769 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4770 {
4771         struct super_block *sb = dentry->d_sb;
4772         struct ext4_sb_info *sbi = EXT4_SB(sb);
4773         struct ext4_super_block *es = sbi->s_es;
4774         ext4_fsblk_t overhead = 0;
4775         u64 fsid;
4776         s64 bfree;
4777
4778         if (!test_opt(sb, MINIX_DF))
4779                 overhead = sbi->s_overhead;
4780
4781         buf->f_type = EXT4_SUPER_MAGIC;
4782         buf->f_bsize = sb->s_blocksize;
4783         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, sbi->s_overhead);
4784         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
4785                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
4786         /* prevent underflow in case that few free space is available */
4787         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
4788         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
4789         if (buf->f_bfree < ext4_r_blocks_count(es))
4790                 buf->f_bavail = 0;
4791         buf->f_files = le32_to_cpu(es->s_inodes_count);
4792         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4793         buf->f_namelen = EXT4_NAME_LEN;
4794         fsid = le64_to_cpup((void *)es->s_uuid) ^
4795                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4796         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4797         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4798
4799         return 0;
4800 }
4801
4802 /* Helper function for writing quotas on sync - we need to start transaction
4803  * before quota file is locked for write. Otherwise the are possible deadlocks:
4804  * Process 1                         Process 2
4805  * ext4_create()                     quota_sync()
4806  *   jbd2_journal_start()                  write_dquot()
4807  *   dquot_initialize()                         down(dqio_mutex)
4808  *     down(dqio_mutex)                    jbd2_journal_start()
4809  *
4810  */
4811
4812 #ifdef CONFIG_QUOTA
4813
4814 static inline struct inode *dquot_to_inode(struct dquot *dquot)
4815 {
4816         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
4817 }
4818
4819 static int ext4_write_dquot(struct dquot *dquot)
4820 {
4821         int ret, err;
4822         handle_t *handle;
4823         struct inode *inode;
4824
4825         inode = dquot_to_inode(dquot);
4826         handle = ext4_journal_start(inode,
4827                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4828         if (IS_ERR(handle))
4829                 return PTR_ERR(handle);
4830         ret = dquot_commit(dquot);
4831         err = ext4_journal_stop(handle);
4832         if (!ret)
4833                 ret = err;
4834         return ret;
4835 }
4836
4837 static int ext4_acquire_dquot(struct dquot *dquot)
4838 {
4839         int ret, err;
4840         handle_t *handle;
4841
4842         handle = ext4_journal_start(dquot_to_inode(dquot),
4843                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4844         if (IS_ERR(handle))
4845                 return PTR_ERR(handle);
4846         ret = dquot_acquire(dquot);
4847         err = ext4_journal_stop(handle);
4848         if (!ret)
4849                 ret = err;
4850         return ret;
4851 }
4852
4853 static int ext4_release_dquot(struct dquot *dquot)
4854 {
4855         int ret, err;
4856         handle_t *handle;
4857
4858         handle = ext4_journal_start(dquot_to_inode(dquot),
4859                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4860         if (IS_ERR(handle)) {
4861                 /* Release dquot anyway to avoid endless cycle in dqput() */
4862                 dquot_release(dquot);
4863                 return PTR_ERR(handle);
4864         }
4865         ret = dquot_release(dquot);
4866         err = ext4_journal_stop(handle);
4867         if (!ret)
4868                 ret = err;
4869         return ret;
4870 }
4871
4872 static int ext4_mark_dquot_dirty(struct dquot *dquot)
4873 {
4874         /* Are we journaling quotas? */
4875         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
4876             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
4877                 dquot_mark_dquot_dirty(dquot);
4878                 return ext4_write_dquot(dquot);
4879         } else {
4880                 return dquot_mark_dquot_dirty(dquot);
4881         }
4882 }
4883
4884 static int ext4_write_info(struct super_block *sb, int type)
4885 {
4886         int ret, err;
4887         handle_t *handle;
4888
4889         /* Data block + inode block */
4890         handle = ext4_journal_start(sb->s_root->d_inode, 2);
4891         if (IS_ERR(handle))
4892                 return PTR_ERR(handle);
4893         ret = dquot_commit_info(sb, type);
4894         err = ext4_journal_stop(handle);
4895         if (!ret)
4896                 ret = err;
4897         return ret;
4898 }
4899
4900 /*
4901  * Turn on quotas during mount time - we need to find
4902  * the quota file and such...
4903  */
4904 static int ext4_quota_on_mount(struct super_block *sb, int type)
4905 {
4906         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4907                                         EXT4_SB(sb)->s_jquota_fmt, type);
4908 }
4909
4910 /*
4911  * Standard function to be called on quota_on
4912  */
4913 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4914                          struct path *path)
4915 {
4916         int err;
4917
4918         if (!test_opt(sb, QUOTA))
4919                 return -EINVAL;
4920
4921         /* Quotafile not on the same filesystem? */
4922         if (path->dentry->d_sb != sb)
4923                 return -EXDEV;
4924         /* Journaling quota? */
4925         if (EXT4_SB(sb)->s_qf_names[type]) {
4926                 /* Quotafile not in fs root? */
4927                 if (path->dentry->d_parent != sb->s_root)
4928                         ext4_msg(sb, KERN_WARNING,
4929                                 "Quota file not on filesystem root. "
4930                                 "Journaled quota will not work");
4931         }
4932
4933         /*
4934          * When we journal data on quota file, we have to flush journal to see
4935          * all updates to the file when we bypass pagecache...
4936          */
4937         if (EXT4_SB(sb)->s_journal &&
4938             ext4_should_journal_data(path->dentry->d_inode)) {
4939                 /*
4940                  * We don't need to lock updates but journal_flush() could
4941                  * otherwise be livelocked...
4942                  */
4943                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4944                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4945                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4946                 if (err)
4947                         return err;
4948         }
4949
4950         return dquot_quota_on(sb, type, format_id, path);
4951 }
4952
4953 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
4954                              unsigned int flags)
4955 {
4956         int err;
4957         struct inode *qf_inode;
4958         unsigned long qf_inums[MAXQUOTAS] = {
4959                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
4960                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
4961         };
4962
4963         BUG_ON(!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA));
4964
4965         if (!qf_inums[type])
4966                 return -EPERM;
4967
4968         qf_inode = ext4_iget(sb, qf_inums[type]);
4969         if (IS_ERR(qf_inode)) {
4970                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
4971                 return PTR_ERR(qf_inode);
4972         }
4973
4974         err = dquot_enable(qf_inode, type, format_id, flags);
4975         iput(qf_inode);
4976
4977         return err;
4978 }
4979
4980 /* Enable usage tracking for all quota types. */
4981 static int ext4_enable_quotas(struct super_block *sb)
4982 {
4983         int type, err = 0;
4984         unsigned long qf_inums[MAXQUOTAS] = {
4985                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
4986                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
4987         };
4988
4989         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
4990         for (type = 0; type < MAXQUOTAS; type++) {
4991                 if (qf_inums[type]) {
4992                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
4993                                                 DQUOT_USAGE_ENABLED);
4994                         if (err) {
4995                                 ext4_warning(sb,
4996                                         "Failed to enable quota (type=%d) "
4997                                         "tracking. Please run e2fsck to fix.",
4998                                         type);
4999                                 return err;
5000                         }
5001                 }
5002         }
5003         return 0;
5004 }
5005
5006 /*
5007  * quota_on function that is used when QUOTA feature is set.
5008  */
5009 static int ext4_quota_on_sysfile(struct super_block *sb, int type,
5010                                  int format_id)
5011 {
5012         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
5013                 return -EINVAL;
5014
5015         /*
5016          * USAGE was enabled at mount time. Only need to enable LIMITS now.
5017          */
5018         return ext4_quota_enable(sb, type, format_id, DQUOT_LIMITS_ENABLED);
5019 }
5020
5021 static int ext4_quota_off(struct super_block *sb, int type)
5022 {
5023         struct inode *inode = sb_dqopt(sb)->files[type];
5024         handle_t *handle;
5025
5026         /* Force all delayed allocation blocks to be allocated.
5027          * Caller already holds s_umount sem */
5028         if (test_opt(sb, DELALLOC))
5029                 sync_filesystem(sb);
5030
5031         if (!inode)
5032                 goto out;
5033
5034         /* Update modification times of quota files when userspace can
5035          * start looking at them */
5036         handle = ext4_journal_start(inode, 1);
5037         if (IS_ERR(handle))
5038                 goto out;
5039         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
5040         ext4_mark_inode_dirty(handle, inode);
5041         ext4_journal_stop(handle);
5042
5043 out:
5044         return dquot_quota_off(sb, type);
5045 }
5046
5047 /*
5048  * quota_off function that is used when QUOTA feature is set.
5049  */
5050 static int ext4_quota_off_sysfile(struct super_block *sb, int type)
5051 {
5052         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
5053                 return -EINVAL;
5054
5055         /* Disable only the limits. */
5056         return dquot_disable(sb, type, DQUOT_LIMITS_ENABLED);
5057 }
5058
5059 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5060  * acquiring the locks... As quota files are never truncated and quota code
5061  * itself serializes the operations (and no one else should touch the files)
5062  * we don't have to be afraid of races */
5063 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5064                                size_t len, loff_t off)
5065 {
5066         struct inode *inode = sb_dqopt(sb)->files[type];
5067         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5068         int err = 0;
5069         int offset = off & (sb->s_blocksize - 1);
5070         int tocopy;
5071         size_t toread;
5072         struct buffer_head *bh;
5073         loff_t i_size = i_size_read(inode);
5074
5075         if (off > i_size)
5076                 return 0;
5077         if (off+len > i_size)
5078                 len = i_size-off;
5079         toread = len;
5080         while (toread > 0) {
5081                 tocopy = sb->s_blocksize - offset < toread ?
5082                                 sb->s_blocksize - offset : toread;
5083                 bh = ext4_bread(NULL, inode, blk, 0, &err);
5084                 if (err)
5085                         return err;
5086                 if (!bh)        /* A hole? */
5087                         memset(data, 0, tocopy);
5088                 else
5089                         memcpy(data, bh->b_data+offset, tocopy);
5090                 brelse(bh);
5091                 offset = 0;
5092                 toread -= tocopy;
5093                 data += tocopy;
5094                 blk++;
5095         }
5096         return len;
5097 }
5098
5099 /* Write to quotafile (we know the transaction is already started and has
5100  * enough credits) */
5101 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5102                                 const char *data, size_t len, loff_t off)
5103 {
5104         struct inode *inode = sb_dqopt(sb)->files[type];
5105         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5106         int err = 0;
5107         int offset = off & (sb->s_blocksize - 1);
5108         struct buffer_head *bh;
5109         handle_t *handle = journal_current_handle();
5110
5111         if (EXT4_SB(sb)->s_journal && !handle) {
5112                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5113                         " cancelled because transaction is not started",
5114                         (unsigned long long)off, (unsigned long long)len);
5115                 return -EIO;
5116         }
5117         /*
5118          * Since we account only one data block in transaction credits,
5119          * then it is impossible to cross a block boundary.
5120          */
5121         if (sb->s_blocksize - offset < len) {
5122                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5123                         " cancelled because not block aligned",
5124                         (unsigned long long)off, (unsigned long long)len);
5125                 return -EIO;
5126         }
5127
5128         bh = ext4_bread(handle, inode, blk, 1, &err);
5129         if (!bh)
5130                 goto out;
5131         err = ext4_journal_get_write_access(handle, bh);
5132         if (err) {
5133                 brelse(bh);
5134                 goto out;
5135         }
5136         lock_buffer(bh);
5137         memcpy(bh->b_data+offset, data, len);
5138         flush_dcache_page(bh->b_page);
5139         unlock_buffer(bh);
5140         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5141         brelse(bh);
5142 out:
5143         if (err)
5144                 return err;
5145         if (inode->i_size < off + len) {
5146                 i_size_write(inode, off + len);
5147                 EXT4_I(inode)->i_disksize = inode->i_size;
5148                 ext4_mark_inode_dirty(handle, inode);
5149         }
5150         return len;
5151 }
5152
5153 #endif
5154
5155 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5156                        const char *dev_name, void *data)
5157 {
5158         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5159 }
5160
5161 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5162 static inline void register_as_ext2(void)
5163 {
5164         int err = register_filesystem(&ext2_fs_type);
5165         if (err)
5166                 printk(KERN_WARNING
5167                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5168 }
5169
5170 static inline void unregister_as_ext2(void)
5171 {
5172         unregister_filesystem(&ext2_fs_type);
5173 }
5174
5175 static inline int ext2_feature_set_ok(struct super_block *sb)
5176 {
5177         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
5178                 return 0;
5179         if (sb->s_flags & MS_RDONLY)
5180                 return 1;
5181         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
5182                 return 0;
5183         return 1;
5184 }
5185 MODULE_ALIAS("ext2");
5186 #else
5187 static inline void register_as_ext2(void) { }
5188 static inline void unregister_as_ext2(void) { }
5189 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5190 #endif
5191
5192 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5193 static inline void register_as_ext3(void)
5194 {
5195         int err = register_filesystem(&ext3_fs_type);
5196         if (err)
5197                 printk(KERN_WARNING
5198                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5199 }
5200
5201 static inline void unregister_as_ext3(void)
5202 {
5203         unregister_filesystem(&ext3_fs_type);
5204 }
5205
5206 static inline int ext3_feature_set_ok(struct super_block *sb)
5207 {
5208         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
5209                 return 0;
5210         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
5211                 return 0;
5212         if (sb->s_flags & MS_RDONLY)
5213                 return 1;
5214         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
5215                 return 0;
5216         return 1;
5217 }
5218 MODULE_ALIAS("ext3");
5219 #else
5220 static inline void register_as_ext3(void) { }
5221 static inline void unregister_as_ext3(void) { }
5222 static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
5223 #endif
5224
5225 static struct file_system_type ext4_fs_type = {
5226         .owner          = THIS_MODULE,
5227         .name           = "ext4",
5228         .mount          = ext4_mount,
5229         .kill_sb        = kill_block_super,
5230         .fs_flags       = FS_REQUIRES_DEV,
5231 };
5232
5233 static int __init ext4_init_feat_adverts(void)
5234 {
5235         struct ext4_features *ef;
5236         int ret = -ENOMEM;
5237
5238         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
5239         if (!ef)
5240                 goto out;
5241
5242         ef->f_kobj.kset = ext4_kset;
5243         init_completion(&ef->f_kobj_unregister);
5244         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
5245                                    "features");
5246         if (ret) {
5247                 kfree(ef);
5248                 goto out;
5249         }
5250
5251         ext4_feat = ef;
5252         ret = 0;
5253 out:
5254         return ret;
5255 }
5256
5257 static void ext4_exit_feat_adverts(void)
5258 {
5259         kobject_put(&ext4_feat->f_kobj);
5260         wait_for_completion(&ext4_feat->f_kobj_unregister);
5261         kfree(ext4_feat);
5262 }
5263
5264 /* Shared across all ext4 file systems */
5265 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5266 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5267
5268 static int __init ext4_init_fs(void)
5269 {
5270         int i, err;
5271
5272         ext4_li_info = NULL;
5273         mutex_init(&ext4_li_mtx);
5274
5275         ext4_check_flag_values();
5276
5277         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5278                 mutex_init(&ext4__aio_mutex[i]);
5279                 init_waitqueue_head(&ext4__ioend_wq[i]);
5280         }
5281
5282         err = ext4_init_pageio();
5283         if (err)
5284                 return err;
5285         err = ext4_init_system_zone();
5286         if (err)
5287                 goto out6;
5288         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
5289         if (!ext4_kset)
5290                 goto out5;
5291         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
5292
5293         err = ext4_init_feat_adverts();
5294         if (err)
5295                 goto out4;
5296
5297         err = ext4_init_mballoc();
5298         if (err)
5299                 goto out3;
5300
5301         err = ext4_init_xattr();
5302         if (err)
5303                 goto out2;
5304         err = init_inodecache();
5305         if (err)
5306                 goto out1;
5307         register_as_ext3();
5308         register_as_ext2();
5309         err = register_filesystem(&ext4_fs_type);
5310         if (err)
5311                 goto out;
5312
5313         return 0;
5314 out:
5315         unregister_as_ext2();
5316         unregister_as_ext3();
5317         destroy_inodecache();
5318 out1:
5319         ext4_exit_xattr();
5320 out2:
5321         ext4_exit_mballoc();
5322 out3:
5323         ext4_exit_feat_adverts();
5324 out4:
5325         if (ext4_proc_root)
5326                 remove_proc_entry("fs/ext4", NULL);
5327         kset_unregister(ext4_kset);
5328 out5:
5329         ext4_exit_system_zone();
5330 out6:
5331         ext4_exit_pageio();
5332         return err;
5333 }
5334
5335 static void __exit ext4_exit_fs(void)
5336 {
5337         ext4_destroy_lazyinit_thread();
5338         unregister_as_ext2();
5339         unregister_as_ext3();
5340         unregister_filesystem(&ext4_fs_type);
5341         destroy_inodecache();
5342         ext4_exit_xattr();
5343         ext4_exit_mballoc();
5344         ext4_exit_feat_adverts();
5345         remove_proc_entry("fs/ext4", NULL);
5346         kset_unregister(ext4_kset);
5347         ext4_exit_system_zone();
5348         ext4_exit_pageio();
5349 }
5350
5351 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5352 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5353 MODULE_LICENSE("GPL");
5354 module_init(ext4_init_fs)
5355 module_exit(ext4_exit_fs)