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