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"       /* Needed for trace points definition */
  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 static int ext4_mballoc_ready;
  63
  64 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  65                              unsigned long journal_devnum);
  66 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  67 static int ext4_commit_super(struct super_block *sb, int sync);
  68 static void ext4_mark_recovery_complete(struct super_block *sb,
  69                                         struct ext4_super_block *es);
  70 static void ext4_clear_journal_err(struct super_block *sb,
  71                                    struct ext4_super_block *es);
  72 static int ext4_sync_fs(struct super_block *sb, int wait);
  73 static int ext4_sync_fs_nojournal(struct super_block *sb, int wait);
  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 static int ext4_reserve_clusters(struct ext4_sb_info *, ext4_fsblk_t);
  87
  88 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
  89 static struct file_system_type ext2_fs_type = {
  90         .owner          = THIS_MODULE,
  91         .name           = "ext2",
  92         .mount          = ext4_mount,
  93         .kill_sb        = kill_block_super,
  94         .fs_flags       = FS_REQUIRES_DEV,
  95 };
  96 MODULE_ALIAS_FS("ext2");
  97 MODULE_ALIAS("ext2");
  98 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
  99 #else
 100 #define IS_EXT2_SB(sb) (0)
 101 #endif
 102
 103
 104 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
 105 static struct file_system_type ext3_fs_type = {
 106         .owner          = THIS_MODULE,
 107         .name           = "ext3",
 108         .mount          = ext4_mount,
 109         .kill_sb        = kill_block_super,
 110         .fs_flags       = FS_REQUIRES_DEV,
 111 };
 112 MODULE_ALIAS_FS("ext3");
 113 MODULE_ALIAS("ext3");
 114 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 115 #else
 116 #define IS_EXT3_SB(sb) (0)
 117 #endif
 118
 119 static int ext4_verify_csum_type(struct super_block *sb,
 120                                  struct ext4_super_block *es)
 121 {
 122         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 123                                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 124                 return 1;
 125
 126         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 127 }
 128
 129 static __le32 ext4_superblock_csum(struct super_block *sb,
 130                                    struct ext4_super_block *es)
 131 {
 132         struct ext4_sb_info *sbi = EXT4_SB(sb);
 133         int offset = offsetof(struct ext4_super_block, s_checksum);
 134         __u32 csum;
 135
 136         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 137
 138         return cpu_to_le32(csum);
 139 }
 140
 141 int ext4_superblock_csum_verify(struct super_block *sb,
 142                                 struct ext4_super_block *es)
 143 {
 144         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 145                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 146                 return 1;
 147
 148         return es->s_checksum == ext4_superblock_csum(sb, es);
 149 }
 150
 151 void ext4_superblock_csum_set(struct super_block *sb)
 152 {
 153         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 154
 155         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 156                 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 157                 return;
 158
 159         es->s_checksum = ext4_superblock_csum(sb, es);
 160 }
 161
 162 void *ext4_kvmalloc(size_t size, gfp_t flags)
 163 {
 164         void *ret;
 165
 166         ret = kmalloc(size, flags | __GFP_NOWARN);
 167         if (!ret)
 168                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 169         return ret;
 170 }
 171
 172 void *ext4_kvzalloc(size_t size, gfp_t flags)
 173 {
 174         void *ret;
 175
 176         ret = kzalloc(size, flags | __GFP_NOWARN);
 177         if (!ret)
 178                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 179         return ret;
 180 }
 181
 182 void ext4_kvfree(void *ptr)
 183 {
 184         if (is_vmalloc_addr(ptr))
 185                 vfree(ptr);
 186         else
 187                 kfree(ptr);
 188
 189 }
 190
 191 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 192                                struct ext4_group_desc *bg)
 193 {
 194         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 195                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 196                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 197 }
 198
 199 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 200                                struct ext4_group_desc *bg)
 201 {
 202         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 203                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 204                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 205 }
 206
 207 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 208                               struct ext4_group_desc *bg)
 209 {
 210         return le32_to_cpu(bg->bg_inode_table_lo) |
 211                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 212                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 213 }
 214
 215 __u32 ext4_free_group_clusters(struct super_block *sb,
 216                                struct ext4_group_desc *bg)
 217 {
 218         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 219                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 220                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 221 }
 222
 223 __u32 ext4_free_inodes_count(struct super_block *sb,
 224                               struct ext4_group_desc *bg)
 225 {
 226         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 227                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 228                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 229 }
 230
 231 __u32 ext4_used_dirs_count(struct super_block *sb,
 232                               struct ext4_group_desc *bg)
 233 {
 234         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 235                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 236                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 237 }
 238
 239 __u32 ext4_itable_unused_count(struct super_block *sb,
 240                               struct ext4_group_desc *bg)
 241 {
 242         return le16_to_cpu(bg->bg_itable_unused_lo) |
 243                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 244                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 245 }
 246
 247 void ext4_block_bitmap_set(struct super_block *sb,
 248                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 249 {
 250         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 251         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 252                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 253 }
 254
 255 void ext4_inode_bitmap_set(struct super_block *sb,
 256                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 257 {
 258         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 259         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 260                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 261 }
 262
 263 void ext4_inode_table_set(struct super_block *sb,
 264                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 265 {
 266         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 267         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 268                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 269 }
 270
 271 void ext4_free_group_clusters_set(struct super_block *sb,
 272                                   struct ext4_group_desc *bg, __u32 count)
 273 {
 274         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 275         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 276                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 277 }
 278
 279 void ext4_free_inodes_set(struct super_block *sb,
 280                           struct ext4_group_desc *bg, __u32 count)
 281 {
 282         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 283         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 284                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 285 }
 286
 287 void ext4_used_dirs_set(struct super_block *sb,
 288                           struct ext4_group_desc *bg, __u32 count)
 289 {
 290         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 291         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 292                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 293 }
 294
 295 void ext4_itable_unused_set(struct super_block *sb,
 296                           struct ext4_group_desc *bg, __u32 count)
 297 {
 298         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 299         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 300                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 301 }
 302
 303
 304 static void __save_error_info(struct super_block *sb, const char *func,
 305                             unsigned int line)
 306 {
 307         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 308
 309         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 310         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 311         es->s_last_error_time = cpu_to_le32(get_seconds());
 312         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 313         es->s_last_error_line = cpu_to_le32(line);
 314         if (!es->s_first_error_time) {
 315                 es->s_first_error_time = es->s_last_error_time;
 316                 strncpy(es->s_first_error_func, func,
 317                         sizeof(es->s_first_error_func));
 318                 es->s_first_error_line = cpu_to_le32(line);
 319                 es->s_first_error_ino = es->s_last_error_ino;
 320                 es->s_first_error_block = es->s_last_error_block;
 321         }
 322         /*
 323          * Start the daily error reporting function if it hasn't been
 324          * started already
 325          */
 326         if (!es->s_error_count)
 327                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 328         le32_add_cpu(&es->s_error_count, 1);
 329 }
 330
 331 static void save_error_info(struct super_block *sb, const char *func,
 332                             unsigned int line)
 333 {
 334         __save_error_info(sb, func, line);
 335         ext4_commit_super(sb, 1);
 336 }
 337
 338 /*
 339  * The del_gendisk() function uninitializes the disk-specific data
 340  * structures, including the bdi structure, without telling anyone
 341  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 342  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 343  * This is a kludge to prevent these oops until we can put in a proper
 344  * hook in del_gendisk() to inform the VFS and file system layers.
 345  */
 346 static int block_device_ejected(struct super_block *sb)
 347 {
 348         struct inode *bd_inode = sb->s_bdev->bd_inode;
 349         struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info;
 350
 351         return bdi->dev == NULL;
 352 }
 353
 354 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 355 {
 356         struct super_block              *sb = journal->j_private;
 357         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 358         int                             error = is_journal_aborted(journal);
 359         struct ext4_journal_cb_entry    *jce;
 360
 361         BUG_ON(txn->t_state == T_FINISHED);
 362         spin_lock(&sbi->s_md_lock);
 363         while (!list_empty(&txn->t_private_list)) {
 364                 jce = list_entry(txn->t_private_list.next,
 365                                  struct ext4_journal_cb_entry, jce_list);
 366                 list_del_init(&jce->jce_list);
 367                 spin_unlock(&sbi->s_md_lock);
 368                 jce->jce_func(sb, jce, error);
 369                 spin_lock(&sbi->s_md_lock);
 370         }
 371         spin_unlock(&sbi->s_md_lock);
 372 }
 373
 374 /* Deal with the reporting of failure conditions on a filesystem such as
 375  * inconsistencies detected or read IO failures.
 376  *
 377  * On ext2, we can store the error state of the filesystem in the
 378  * superblock.  That is not possible on ext4, because we may have other
 379  * write ordering constraints on the superblock which prevent us from
 380  * writing it out straight away; and given that the journal is about to
 381  * be aborted, we can't rely on the current, or future, transactions to
 382  * write out the superblock safely.
 383  *
 384  * We'll just use the jbd2_journal_abort() error code to record an error in
 385  * the journal instead.  On recovery, the journal will complain about
 386  * that error until we've noted it down and cleared it.
 387  */
 388
 389 static void ext4_handle_error(struct super_block *sb)
 390 {
 391         if (sb->s_flags & MS_RDONLY)
 392                 return;
 393
 394         if (!test_opt(sb, ERRORS_CONT)) {
 395                 journal_t *journal = EXT4_SB(sb)->s_journal;
 396
 397                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 398                 if (journal)
 399                         jbd2_journal_abort(journal, -EIO);
 400         }
 401         if (test_opt(sb, ERRORS_RO)) {
 402                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 403                 /*
 404                  * Make sure updated value of ->s_mount_flags will be visible
 405                  * before ->s_flags update
 406                  */
 407                 smp_wmb();
 408                 sb->s_flags |= MS_RDONLY;
 409         }
 410         if (test_opt(sb, ERRORS_PANIC))
 411                 panic("EXT4-fs (device %s): panic forced after error\n",
 412                         sb->s_id);
 413 }
 414
 415 #define ext4_error_ratelimit(sb)                                        \
 416                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 417                              "EXT4-fs error")
 418
 419 void __ext4_error(struct super_block *sb, const char *function,
 420                   unsigned int line, const char *fmt, ...)
 421 {
 422         struct va_format vaf;
 423         va_list args;
 424
 425         if (ext4_error_ratelimit(sb)) {
 426                 va_start(args, fmt);
 427                 vaf.fmt = fmt;
 428                 vaf.va = &args;
 429                 printk(KERN_CRIT
 430                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 431                        sb->s_id, function, line, current->comm, &vaf);
 432                 va_end(args);
 433         }
 434         save_error_info(sb, function, line);
 435         ext4_handle_error(sb);
 436 }
 437
 438 void __ext4_error_inode(struct inode *inode, const char *function,
 439                         unsigned int line, ext4_fsblk_t block,
 440                         const char *fmt, ...)
 441 {
 442         va_list args;
 443         struct va_format vaf;
 444         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 445
 446         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 447         es->s_last_error_block = cpu_to_le64(block);
 448         if (ext4_error_ratelimit(inode->i_sb)) {
 449                 va_start(args, fmt);
 450                 vaf.fmt = fmt;
 451                 vaf.va = &args;
 452                 if (block)
 453                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 454                                "inode #%lu: block %llu: comm %s: %pV\n",
 455                                inode->i_sb->s_id, function, line, inode->i_ino,
 456                                block, current->comm, &vaf);
 457                 else
 458                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 459                                "inode #%lu: comm %s: %pV\n",
 460                                inode->i_sb->s_id, function, line, inode->i_ino,
 461                                current->comm, &vaf);
 462                 va_end(args);
 463         }
 464         save_error_info(inode->i_sb, function, line);
 465         ext4_handle_error(inode->i_sb);
 466 }
 467
 468 void __ext4_error_file(struct file *file, const char *function,
 469                        unsigned int line, ext4_fsblk_t block,
 470                        const char *fmt, ...)
 471 {
 472         va_list args;
 473         struct va_format vaf;
 474         struct ext4_super_block *es;
 475         struct inode *inode = file_inode(file);
 476         char pathname[80], *path;
 477
 478         es = EXT4_SB(inode->i_sb)->s_es;
 479         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 480         if (ext4_error_ratelimit(inode->i_sb)) {
 481                 path = d_path(&(file->f_path), pathname, sizeof(pathname));
 482                 if (IS_ERR(path))
 483                         path = "(unknown)";
 484                 va_start(args, fmt);
 485                 vaf.fmt = fmt;
 486                 vaf.va = &args;
 487                 if (block)
 488                         printk(KERN_CRIT
 489                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 490                                "block %llu: comm %s: path %s: %pV\n",
 491                                inode->i_sb->s_id, function, line, inode->i_ino,
 492                                block, current->comm, path, &vaf);
 493                 else
 494                         printk(KERN_CRIT
 495                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 496                                "comm %s: path %s: %pV\n",
 497                                inode->i_sb->s_id, function, line, inode->i_ino,
 498                                current->comm, path, &vaf);
 499                 va_end(args);
 500         }
 501         save_error_info(inode->i_sb, function, line);
 502         ext4_handle_error(inode->i_sb);
 503 }
 504
 505 const char *ext4_decode_error(struct super_block *sb, int errno,
 506                               char nbuf[16])
 507 {
 508         char *errstr = NULL;
 509
 510         switch (errno) {
 511         case -EIO:
 512                 errstr = "IO failure";
 513                 break;
 514         case -ENOMEM:
 515                 errstr = "Out of memory";
 516                 break;
 517         case -EROFS:
 518                 if (!sb || (EXT4_SB(sb)->s_journal &&
 519                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 520                         errstr = "Journal has aborted";
 521                 else
 522                         errstr = "Readonly filesystem";
 523                 break;
 524         default:
 525                 /* If the caller passed in an extra buffer for unknown
 526                  * errors, textualise them now.  Else we just return
 527                  * NULL. */
 528                 if (nbuf) {
 529                         /* Check for truncated error codes... */
 530                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 531                                 errstr = nbuf;
 532                 }
 533                 break;
 534         }
 535
 536         return errstr;
 537 }
 538
 539 /* __ext4_std_error decodes expected errors from journaling functions
 540  * automatically and invokes the appropriate error response.  */
 541
 542 void __ext4_std_error(struct super_block *sb, const char *function,
 543                       unsigned int line, int errno)
 544 {
 545         char nbuf[16];
 546         const char *errstr;
 547
 548         /* Special case: if the error is EROFS, and we're not already
 549          * inside a transaction, then there's really no point in logging
 550          * an error. */
 551         if (errno == -EROFS && journal_current_handle() == NULL &&
 552             (sb->s_flags & MS_RDONLY))
 553                 return;
 554
 555         if (ext4_error_ratelimit(sb)) {
 556                 errstr = ext4_decode_error(sb, errno, nbuf);
 557                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 558                        sb->s_id, function, line, errstr);
 559         }
 560
 561         save_error_info(sb, function, line);
 562         ext4_handle_error(sb);
 563 }
 564
 565 /*
 566  * ext4_abort is a much stronger failure handler than ext4_error.  The
 567  * abort function may be used to deal with unrecoverable failures such
 568  * as journal IO errors or ENOMEM at a critical moment in log management.
 569  *
 570  * We unconditionally force the filesystem into an ABORT|READONLY state,
 571  * unless the error response on the fs has been set to panic in which
 572  * case we take the easy way out and panic immediately.
 573  */
 574
 575 void __ext4_abort(struct super_block *sb, const char *function,
 576                 unsigned int line, const char *fmt, ...)
 577 {
 578         va_list args;
 579
 580         save_error_info(sb, function, line);
 581         va_start(args, fmt);
 582         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 583                function, line);
 584         vprintk(fmt, args);
 585         printk("\n");
 586         va_end(args);
 587
 588         if ((sb->s_flags & MS_RDONLY) == 0) {
 589                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 590                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 591                 /*
 592                  * Make sure updated value of ->s_mount_flags will be visible
 593                  * before ->s_flags update
 594                  */
 595                 smp_wmb();
 596                 sb->s_flags |= MS_RDONLY;
 597                 if (EXT4_SB(sb)->s_journal)
 598                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 599                 save_error_info(sb, function, line);
 600         }
 601         if (test_opt(sb, ERRORS_PANIC))
 602                 panic("EXT4-fs panic from previous error\n");
 603 }
 604
 605 void __ext4_msg(struct super_block *sb,
 606                 const char *prefix, const char *fmt, ...)
 607 {
 608         struct va_format vaf;
 609         va_list args;
 610
 611         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 612                 return;
 613
 614         va_start(args, fmt);
 615         vaf.fmt = fmt;
 616         vaf.va = &args;
 617         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 618         va_end(args);
 619 }
 620
 621 void __ext4_warning(struct super_block *sb, const char *function,
 622                     unsigned int line, const char *fmt, ...)
 623 {
 624         struct va_format vaf;
 625         va_list args;
 626
 627         if (!___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 628                           "EXT4-fs warning"))
 629                 return;
 630
 631         va_start(args, fmt);
 632         vaf.fmt = fmt;
 633         vaf.va = &args;
 634         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 635                sb->s_id, function, line, &vaf);
 636         va_end(args);
 637 }
 638
 639 void __ext4_grp_locked_error(const char *function, unsigned int line,
 640                              struct super_block *sb, ext4_group_t grp,
 641                              unsigned long ino, ext4_fsblk_t block,
 642                              const char *fmt, ...)
 643 __releases(bitlock)
 644 __acquires(bitlock)
 645 {
 646         struct va_format vaf;
 647         va_list args;
 648         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 649
 650         es->s_last_error_ino = cpu_to_le32(ino);
 651         es->s_last_error_block = cpu_to_le64(block);
 652         __save_error_info(sb, function, line);
 653
 654         if (ext4_error_ratelimit(sb)) {
 655                 va_start(args, fmt);
 656                 vaf.fmt = fmt;
 657                 vaf.va = &args;
 658                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 659                        sb->s_id, function, line, grp);
 660                 if (ino)
 661                         printk(KERN_CONT "inode %lu: ", ino);
 662                 if (block)
 663                         printk(KERN_CONT "block %llu:",
 664                                (unsigned long long) block);
 665                 printk(KERN_CONT "%pV\n", &vaf);
 666                 va_end(args);
 667         }
 668
 669         if (test_opt(sb, ERRORS_CONT)) {
 670                 ext4_commit_super(sb, 0);
 671                 return;
 672         }
 673
 674         ext4_unlock_group(sb, grp);
 675         ext4_handle_error(sb);
 676         /*
 677          * We only get here in the ERRORS_RO case; relocking the group
 678          * may be dangerous, but nothing bad will happen since the
 679          * filesystem will have already been marked read/only and the
 680          * journal has been aborted.  We return 1 as a hint to callers
 681          * who might what to use the return value from
 682          * ext4_grp_locked_error() to distinguish between the
 683          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 684          * aggressively from the ext4 function in question, with a
 685          * more appropriate error code.
 686          */
 687         ext4_lock_group(sb, grp);
 688         return;
 689 }
 690
 691 void ext4_update_dynamic_rev(struct super_block *sb)
 692 {
 693         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 694
 695         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 696                 return;
 697
 698         ext4_warning(sb,
 699                      "updating to rev %d because of new feature flag, "
 700                      "running e2fsck is recommended",
 701                      EXT4_DYNAMIC_REV);
 702
 703         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 704         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 705         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 706         /* leave es->s_feature_*compat flags alone */
 707         /* es->s_uuid will be set by e2fsck if empty */
 708
 709         /*
 710          * The rest of the superblock fields should be zero, and if not it
 711          * means they are likely already in use, so leave them alone.  We
 712          * can leave it up to e2fsck to clean up any inconsistencies there.
 713          */
 714 }
 715
 716 /*
 717  * Open the external journal device
 718  */
 719 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 720 {
 721         struct block_device *bdev;
 722         char b[BDEVNAME_SIZE];
 723
 724         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 725         if (IS_ERR(bdev))
 726                 goto fail;
 727         return bdev;
 728
 729 fail:
 730         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 731                         __bdevname(dev, b), PTR_ERR(bdev));
 732         return NULL;
 733 }
 734
 735 /*
 736  * Release the journal device
 737  */
 738 static void ext4_blkdev_put(struct block_device *bdev)
 739 {
 740         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 741 }
 742
 743 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 744 {
 745         struct block_device *bdev;
 746         bdev = sbi->journal_bdev;
 747         if (bdev) {
 748                 ext4_blkdev_put(bdev);
 749                 sbi->journal_bdev = NULL;
 750         }
 751 }
 752
 753 static inline struct inode *orphan_list_entry(struct list_head *l)
 754 {
 755         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 756 }
 757
 758 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 759 {
 760         struct list_head *l;
 761
 762         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 763                  le32_to_cpu(sbi->s_es->s_last_orphan));
 764
 765         printk(KERN_ERR "sb_info orphan list:\n");
 766         list_for_each(l, &sbi->s_orphan) {
 767                 struct inode *inode = orphan_list_entry(l);
 768                 printk(KERN_ERR "  "
 769                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 770                        inode->i_sb->s_id, inode->i_ino, inode,
 771                        inode->i_mode, inode->i_nlink,
 772                        NEXT_ORPHAN(inode));
 773         }
 774 }
 775
 776 static void ext4_put_super(struct super_block *sb)
 777 {
 778         struct ext4_sb_info *sbi = EXT4_SB(sb);
 779         struct ext4_super_block *es = sbi->s_es;
 780         int i, err;
 781
 782         ext4_unregister_li_request(sb);
 783         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 784
 785         flush_workqueue(sbi->rsv_conversion_wq);
 786         destroy_workqueue(sbi->rsv_conversion_wq);
 787
 788         if (sbi->s_journal) {
 789                 err = jbd2_journal_destroy(sbi->s_journal);
 790                 sbi->s_journal = NULL;
 791                 if (err < 0)
 792                         ext4_abort(sb, "Couldn't clean up the journal");
 793         }
 794
 795         ext4_es_unregister_shrinker(sbi);
 796         del_timer_sync(&sbi->s_err_report);
 797         ext4_release_system_zone(sb);
 798         ext4_mb_release(sb);
 799         ext4_ext_release(sb);
 800         ext4_xattr_put_super(sb);
 801
 802         if (!(sb->s_flags & MS_RDONLY)) {
 803                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 804                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 805         }
 806         if (!(sb->s_flags & MS_RDONLY))
 807                 ext4_commit_super(sb, 1);
 808
 809         if (sbi->s_proc) {
 810                 remove_proc_entry("options", sbi->s_proc);
 811                 remove_proc_entry(sb->s_id, ext4_proc_root);
 812         }
 813         kobject_del(&sbi->s_kobj);
 814
 815         for (i = 0; i < sbi->s_gdb_count; i++)
 816                 brelse(sbi->s_group_desc[i]);
 817         ext4_kvfree(sbi->s_group_desc);
 818         ext4_kvfree(sbi->s_flex_groups);
 819         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 820         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 821         percpu_counter_destroy(&sbi->s_dirs_counter);
 822         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 823         percpu_counter_destroy(&sbi->s_extent_cache_cnt);
 824         brelse(sbi->s_sbh);
 825 #ifdef CONFIG_QUOTA
 826         for (i = 0; i < MAXQUOTAS; i++)
 827                 kfree(sbi->s_qf_names[i]);
 828 #endif
 829
 830         /* Debugging code just in case the in-memory inode orphan list
 831          * isn't empty.  The on-disk one can be non-empty if we've
 832          * detected an error and taken the fs readonly, but the
 833          * in-memory list had better be clean by this point. */
 834         if (!list_empty(&sbi->s_orphan))
 835                 dump_orphan_list(sb, sbi);
 836         J_ASSERT(list_empty(&sbi->s_orphan));
 837
 838         invalidate_bdev(sb->s_bdev);
 839         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 840                 /*
 841                  * Invalidate the journal device's buffers.  We don't want them
 842                  * floating about in memory - the physical journal device may
 843                  * hotswapped, and it breaks the `ro-after' testing code.
 844                  */
 845                 sync_blockdev(sbi->journal_bdev);
 846                 invalidate_bdev(sbi->journal_bdev);
 847                 ext4_blkdev_remove(sbi);
 848         }
 849         if (sbi->s_mb_cache) {
 850                 ext4_xattr_destroy_cache(sbi->s_mb_cache);
 851                 sbi->s_mb_cache = NULL;
 852         }
 853         if (sbi->s_mmp_tsk)
 854                 kthread_stop(sbi->s_mmp_tsk);
 855         sb->s_fs_info = NULL;
 856         /*
 857          * Now that we are completely done shutting down the
 858          * superblock, we need to actually destroy the kobject.
 859          */
 860         kobject_put(&sbi->s_kobj);
 861         wait_for_completion(&sbi->s_kobj_unregister);
 862         if (sbi->s_chksum_driver)
 863                 crypto_free_shash(sbi->s_chksum_driver);
 864         kfree(sbi->s_blockgroup_lock);
 865         kfree(sbi);
 866 }
 867
 868 static struct kmem_cache *ext4_inode_cachep;
 869
 870 /*
 871  * Called inside transaction, so use GFP_NOFS
 872  */
 873 static struct inode *ext4_alloc_inode(struct super_block *sb)
 874 {
 875         struct ext4_inode_info *ei;
 876
 877         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 878         if (!ei)
 879                 return NULL;
 880
 881         ei->vfs_inode.i_version = 1;
 882         INIT_LIST_HEAD(&ei->i_prealloc_list);
 883         spin_lock_init(&ei->i_prealloc_lock);
 884         ext4_es_init_tree(&ei->i_es_tree);
 885         rwlock_init(&ei->i_es_lock);
 886         INIT_LIST_HEAD(&ei->i_es_lru);
 887         ei->i_es_lru_nr = 0;
 888         ei->i_touch_when = 0;
 889         ei->i_reserved_data_blocks = 0;
 890         ei->i_reserved_meta_blocks = 0;
 891         ei->i_allocated_meta_blocks = 0;
 892         ei->i_da_metadata_calc_len = 0;
 893         ei->i_da_metadata_calc_last_lblock = 0;
 894         spin_lock_init(&(ei->i_block_reservation_lock));
 895 #ifdef CONFIG_QUOTA
 896         ei->i_reserved_quota = 0;
 897 #endif
 898         ei->jinode = NULL;
 899         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
 900         spin_lock_init(&ei->i_completed_io_lock);
 901         ei->i_sync_tid = 0;
 902         ei->i_datasync_tid = 0;
 903         atomic_set(&ei->i_ioend_count, 0);
 904         atomic_set(&ei->i_unwritten, 0);
 905         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
 906
 907         return &ei->vfs_inode;
 908 }
 909
 910 static int ext4_drop_inode(struct inode *inode)
 911 {
 912         int drop = generic_drop_inode(inode);
 913
 914         trace_ext4_drop_inode(inode, drop);
 915         return drop;
 916 }
 917
 918 static void ext4_i_callback(struct rcu_head *head)
 919 {
 920         struct inode *inode = container_of(head, struct inode, i_rcu);
 921         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 922 }
 923
 924 static void ext4_destroy_inode(struct inode *inode)
 925 {
 926         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 927                 ext4_msg(inode->i_sb, KERN_ERR,
 928                          "Inode %lu (%p): orphan list check failed!",
 929                          inode->i_ino, EXT4_I(inode));
 930                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 931                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 932                                 true);
 933                 dump_stack();
 934         }
 935         call_rcu(&inode->i_rcu, ext4_i_callback);
 936 }
 937
 938 static void init_once(void *foo)
 939 {
 940         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 941
 942         INIT_LIST_HEAD(&ei->i_orphan);
 943         init_rwsem(&ei->xattr_sem);
 944         init_rwsem(&ei->i_data_sem);
 945         inode_init_once(&ei->vfs_inode);
 946 }
 947
 948 static int __init init_inodecache(void)
 949 {
 950         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 951                                              sizeof(struct ext4_inode_info),
 952                                              0, (SLAB_RECLAIM_ACCOUNT|
 953                                                 SLAB_MEM_SPREAD),
 954                                              init_once);
 955         if (ext4_inode_cachep == NULL)
 956                 return -ENOMEM;
 957         return 0;
 958 }
 959
 960 static void destroy_inodecache(void)
 961 {
 962         /*
 963          * Make sure all delayed rcu free inodes are flushed before we
 964          * destroy cache.
 965          */
 966         rcu_barrier();
 967         kmem_cache_destroy(ext4_inode_cachep);
 968 }
 969
 970 void ext4_clear_inode(struct inode *inode)
 971 {
 972         invalidate_inode_buffers(inode);
 973         clear_inode(inode);
 974         dquot_drop(inode);
 975         ext4_discard_preallocations(inode);
 976         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
 977         ext4_es_lru_del(inode);
 978         if (EXT4_I(inode)->jinode) {
 979                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
 980                                                EXT4_I(inode)->jinode);
 981                 jbd2_free_inode(EXT4_I(inode)->jinode);
 982                 EXT4_I(inode)->jinode = NULL;
 983         }
 984 }
 985
 986 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 987                                         u64 ino, u32 generation)
 988 {
 989         struct inode *inode;
 990
 991         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 992                 return ERR_PTR(-ESTALE);
 993         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 994                 return ERR_PTR(-ESTALE);
 995
 996         /* iget isn't really right if the inode is currently unallocated!!
 997          *
 998          * ext4_read_inode will return a bad_inode if the inode had been
 999          * deleted, so we should be safe.
1000          *
1001          * Currently we don't know the generation for parent directory, so
1002          * a generation of 0 means "accept any"
1003          */
1004         inode = ext4_iget(sb, ino);
1005         if (IS_ERR(inode))
1006                 return ERR_CAST(inode);
1007         if (generation && inode->i_generation != generation) {
1008                 iput(inode);
1009                 return ERR_PTR(-ESTALE);
1010         }
1011
1012         return inode;
1013 }
1014
1015 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1016                                         int fh_len, int fh_type)
1017 {
1018         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1019                                     ext4_nfs_get_inode);
1020 }
1021
1022 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1023                                         int fh_len, int fh_type)
1024 {
1025         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1026                                     ext4_nfs_get_inode);
1027 }
1028
1029 /*
1030  * Try to release metadata pages (indirect blocks, directories) which are
1031  * mapped via the block device.  Since these pages could have journal heads
1032  * which would prevent try_to_free_buffers() from freeing them, we must use
1033  * jbd2 layer's try_to_free_buffers() function to release them.
1034  */
1035 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1036                                  gfp_t wait)
1037 {
1038         journal_t *journal = EXT4_SB(sb)->s_journal;
1039
1040         WARN_ON(PageChecked(page));
1041         if (!page_has_buffers(page))
1042                 return 0;
1043         if (journal)
1044                 return jbd2_journal_try_to_free_buffers(journal, page,
1045                                                         wait & ~__GFP_WAIT);
1046         return try_to_free_buffers(page);
1047 }
1048
1049 #ifdef CONFIG_QUOTA
1050 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1051 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1052
1053 static int ext4_write_dquot(struct dquot *dquot);
1054 static int ext4_acquire_dquot(struct dquot *dquot);
1055 static int ext4_release_dquot(struct dquot *dquot);
1056 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1057 static int ext4_write_info(struct super_block *sb, int type);
1058 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1059                          struct path *path);
1060 static int ext4_quota_on_sysfile(struct super_block *sb, int type,
1061                                  int format_id);
1062 static int ext4_quota_off(struct super_block *sb, int type);
1063 static int ext4_quota_off_sysfile(struct super_block *sb, int type);
1064 static int ext4_quota_on_mount(struct super_block *sb, int type);
1065 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1066                                size_t len, loff_t off);
1067 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1068                                 const char *data, size_t len, loff_t off);
1069 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1070                              unsigned int flags);
1071 static int ext4_enable_quotas(struct super_block *sb);
1072
1073 static const struct dquot_operations ext4_quota_operations = {
1074         .get_reserved_space = ext4_get_reserved_space,
1075         .write_dquot    = ext4_write_dquot,
1076         .acquire_dquot  = ext4_acquire_dquot,
1077         .release_dquot  = ext4_release_dquot,
1078         .mark_dirty     = ext4_mark_dquot_dirty,
1079         .write_info     = ext4_write_info,
1080         .alloc_dquot    = dquot_alloc,
1081         .destroy_dquot  = dquot_destroy,
1082 };
1083
1084 static const struct quotactl_ops ext4_qctl_operations = {
1085         .quota_on       = ext4_quota_on,
1086         .quota_off      = ext4_quota_off,
1087         .quota_sync     = dquot_quota_sync,
1088         .get_info       = dquot_get_dqinfo,
1089         .set_info       = dquot_set_dqinfo,
1090         .get_dqblk      = dquot_get_dqblk,
1091         .set_dqblk      = dquot_set_dqblk
1092 };
1093
1094 static const struct quotactl_ops ext4_qctl_sysfile_operations = {
1095         .quota_on_meta  = ext4_quota_on_sysfile,
1096         .quota_off      = ext4_quota_off_sysfile,
1097         .quota_sync     = dquot_quota_sync,
1098         .get_info       = dquot_get_dqinfo,
1099         .set_info       = dquot_set_dqinfo,
1100         .get_dqblk      = dquot_get_dqblk,
1101         .set_dqblk      = dquot_set_dqblk
1102 };
1103 #endif
1104
1105 static const struct super_operations ext4_sops = {
1106         .alloc_inode    = ext4_alloc_inode,
1107         .destroy_inode  = ext4_destroy_inode,
1108         .write_inode    = ext4_write_inode,
1109         .dirty_inode    = ext4_dirty_inode,
1110         .drop_inode     = ext4_drop_inode,
1111         .evict_inode    = ext4_evict_inode,
1112         .put_super      = ext4_put_super,
1113         .sync_fs        = ext4_sync_fs,
1114         .freeze_fs      = ext4_freeze,
1115         .unfreeze_fs    = ext4_unfreeze,
1116         .statfs         = ext4_statfs,
1117         .remount_fs     = ext4_remount,
1118         .show_options   = ext4_show_options,
1119 #ifdef CONFIG_QUOTA
1120         .quota_read     = ext4_quota_read,
1121         .quota_write    = ext4_quota_write,
1122 #endif
1123         .bdev_try_to_free_page = bdev_try_to_free_page,
1124 };
1125
1126 static const struct super_operations ext4_nojournal_sops = {
1127         .alloc_inode    = ext4_alloc_inode,
1128         .destroy_inode  = ext4_destroy_inode,
1129         .write_inode    = ext4_write_inode,
1130         .dirty_inode    = ext4_dirty_inode,
1131         .drop_inode     = ext4_drop_inode,
1132         .evict_inode    = ext4_evict_inode,
1133         .sync_fs        = ext4_sync_fs_nojournal,
1134         .put_super      = ext4_put_super,
1135         .statfs         = ext4_statfs,
1136         .remount_fs     = ext4_remount,
1137         .show_options   = ext4_show_options,
1138 #ifdef CONFIG_QUOTA
1139         .quota_read     = ext4_quota_read,
1140         .quota_write    = ext4_quota_write,
1141 #endif
1142         .bdev_try_to_free_page = bdev_try_to_free_page,
1143 };
1144
1145 static const struct export_operations ext4_export_ops = {
1146         .fh_to_dentry = ext4_fh_to_dentry,
1147         .fh_to_parent = ext4_fh_to_parent,
1148         .get_parent = ext4_get_parent,
1149 };
1150
1151 enum {
1152         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1153         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1154         Opt_nouid32, Opt_debug, Opt_removed,
1155         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1156         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1157         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1158         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1159         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1160         Opt_data_err_abort, Opt_data_err_ignore,
1161         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1162         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1163         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1164         Opt_usrquota, Opt_grpquota, Opt_i_version,
1165         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1166         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1167         Opt_inode_readahead_blks, Opt_journal_ioprio,
1168         Opt_dioread_nolock, Opt_dioread_lock,
1169         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1170         Opt_max_dir_size_kb,
1171 };
1172
1173 static const match_table_t tokens = {
1174         {Opt_bsd_df, "bsddf"},
1175         {Opt_minix_df, "minixdf"},
1176         {Opt_grpid, "grpid"},
1177         {Opt_grpid, "bsdgroups"},
1178         {Opt_nogrpid, "nogrpid"},
1179         {Opt_nogrpid, "sysvgroups"},
1180         {Opt_resgid, "resgid=%u"},
1181         {Opt_resuid, "resuid=%u"},
1182         {Opt_sb, "sb=%u"},
1183         {Opt_err_cont, "errors=continue"},
1184         {Opt_err_panic, "errors=panic"},
1185         {Opt_err_ro, "errors=remount-ro"},
1186         {Opt_nouid32, "nouid32"},
1187         {Opt_debug, "debug"},
1188         {Opt_removed, "oldalloc"},
1189         {Opt_removed, "orlov"},
1190         {Opt_user_xattr, "user_xattr"},
1191         {Opt_nouser_xattr, "nouser_xattr"},
1192         {Opt_acl, "acl"},
1193         {Opt_noacl, "noacl"},
1194         {Opt_noload, "norecovery"},
1195         {Opt_noload, "noload"},
1196         {Opt_removed, "nobh"},
1197         {Opt_removed, "bh"},
1198         {Opt_commit, "commit=%u"},
1199         {Opt_min_batch_time, "min_batch_time=%u"},
1200         {Opt_max_batch_time, "max_batch_time=%u"},
1201         {Opt_journal_dev, "journal_dev=%u"},
1202         {Opt_journal_path, "journal_path=%s"},
1203         {Opt_journal_checksum, "journal_checksum"},
1204         {Opt_journal_async_commit, "journal_async_commit"},
1205         {Opt_abort, "abort"},
1206         {Opt_data_journal, "data=journal"},
1207         {Opt_data_ordered, "data=ordered"},
1208         {Opt_data_writeback, "data=writeback"},
1209         {Opt_data_err_abort, "data_err=abort"},
1210         {Opt_data_err_ignore, "data_err=ignore"},
1211         {Opt_offusrjquota, "usrjquota="},
1212         {Opt_usrjquota, "usrjquota=%s"},
1213         {Opt_offgrpjquota, "grpjquota="},
1214         {Opt_grpjquota, "grpjquota=%s"},
1215         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1216         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1217         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1218         {Opt_grpquota, "grpquota"},
1219         {Opt_noquota, "noquota"},
1220         {Opt_quota, "quota"},
1221         {Opt_usrquota, "usrquota"},
1222         {Opt_barrier, "barrier=%u"},
1223         {Opt_barrier, "barrier"},
1224         {Opt_nobarrier, "nobarrier"},
1225         {Opt_i_version, "i_version"},
1226         {Opt_stripe, "stripe=%u"},
1227         {Opt_delalloc, "delalloc"},
1228         {Opt_nodelalloc, "nodelalloc"},
1229         {Opt_removed, "mblk_io_submit"},
1230         {Opt_removed, "nomblk_io_submit"},
1231         {Opt_block_validity, "block_validity"},
1232         {Opt_noblock_validity, "noblock_validity"},
1233         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1234         {Opt_journal_ioprio, "journal_ioprio=%u"},
1235         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1236         {Opt_auto_da_alloc, "auto_da_alloc"},
1237         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1238         {Opt_dioread_nolock, "dioread_nolock"},
1239         {Opt_dioread_lock, "dioread_lock"},
1240         {Opt_discard, "discard"},
1241         {Opt_nodiscard, "nodiscard"},
1242         {Opt_init_itable, "init_itable=%u"},
1243         {Opt_init_itable, "init_itable"},
1244         {Opt_noinit_itable, "noinit_itable"},
1245         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1246         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1247         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1248         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1249         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1250         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1251         {Opt_err, NULL},
1252 };
1253
1254 static ext4_fsblk_t get_sb_block(void **data)
1255 {
1256         ext4_fsblk_t    sb_block;
1257         char            *options = (char *) *data;
1258
1259         if (!options || strncmp(options, "sb=", 3) != 0)
1260                 return 1;       /* Default location */
1261
1262         options += 3;
1263         /* TODO: use simple_strtoll with >32bit ext4 */
1264         sb_block = simple_strtoul(options, &options, 0);
1265         if (*options && *options != ',') {
1266                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1267                        (char *) *data);
1268                 return 1;
1269         }
1270         if (*options == ',')
1271                 options++;
1272         *data = (void *) options;
1273
1274         return sb_block;
1275 }
1276
1277 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1278 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1279         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1280
1281 #ifdef CONFIG_QUOTA
1282 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1283 {
1284         struct ext4_sb_info *sbi = EXT4_SB(sb);
1285         char *qname;
1286         int ret = -1;
1287
1288         if (sb_any_quota_loaded(sb) &&
1289                 !sbi->s_qf_names[qtype]) {
1290                 ext4_msg(sb, KERN_ERR,
1291                         "Cannot change journaled "
1292                         "quota options when quota turned on");
1293                 return -1;
1294         }
1295         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1296                 ext4_msg(sb, KERN_ERR, "Cannot set journaled quota options "
1297                          "when QUOTA feature is enabled");
1298                 return -1;
1299         }
1300         qname = match_strdup(args);
1301         if (!qname) {
1302                 ext4_msg(sb, KERN_ERR,
1303                         "Not enough memory for storing quotafile name");
1304                 return -1;
1305         }
1306         if (sbi->s_qf_names[qtype]) {
1307                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1308                         ret = 1;
1309                 else
1310                         ext4_msg(sb, KERN_ERR,
1311                                  "%s quota file already specified",
1312                                  QTYPE2NAME(qtype));
1313                 goto errout;
1314         }
1315         if (strchr(qname, '/')) {
1316                 ext4_msg(sb, KERN_ERR,
1317                         "quotafile must be on filesystem root");
1318                 goto errout;
1319         }
1320         sbi->s_qf_names[qtype] = qname;
1321         set_opt(sb, QUOTA);
1322         return 1;
1323 errout:
1324         kfree(qname);
1325         return ret;
1326 }
1327
1328 static int clear_qf_name(struct super_block *sb, int qtype)
1329 {
1330
1331         struct ext4_sb_info *sbi = EXT4_SB(sb);
1332
1333         if (sb_any_quota_loaded(sb) &&
1334                 sbi->s_qf_names[qtype]) {
1335                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1336                         " when quota turned on");
1337                 return -1;
1338         }
1339         kfree(sbi->s_qf_names[qtype]);
1340         sbi->s_qf_names[qtype] = NULL;
1341         return 1;
1342 }
1343 #endif
1344
1345 #define MOPT_SET        0x0001
1346 #define MOPT_CLEAR      0x0002
1347 #define MOPT_NOSUPPORT  0x0004
1348 #define MOPT_EXPLICIT   0x0008
1349 #define MOPT_CLEAR_ERR  0x0010
1350 #define MOPT_GTE0       0x0020
1351 #ifdef CONFIG_QUOTA
1352 #define MOPT_Q          0
1353 #define MOPT_QFMT       0x0040
1354 #else
1355 #define MOPT_Q          MOPT_NOSUPPORT
1356 #define MOPT_QFMT       MOPT_NOSUPPORT
1357 #endif
1358 #define MOPT_DATAJ      0x0080
1359 #define MOPT_NO_EXT2    0x0100
1360 #define MOPT_NO_EXT3    0x0200
1361 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1362 #define MOPT_STRING     0x0400
1363
1364 static const struct mount_opts {
1365         int     token;
1366         int     mount_opt;
1367         int     flags;
1368 } ext4_mount_opts[] = {
1369         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1370         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1371         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1372         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1373         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1374         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1375         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1376          MOPT_EXT4_ONLY | MOPT_SET},
1377         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1378          MOPT_EXT4_ONLY | MOPT_CLEAR},
1379         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1380         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1381         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1382          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1383         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1384          MOPT_EXT4_ONLY | MOPT_CLEAR},
1385         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1386          MOPT_EXT4_ONLY | MOPT_SET},
1387         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1388                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1389          MOPT_EXT4_ONLY | MOPT_SET},
1390         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1391         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1392         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1393         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1394         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1395          MOPT_NO_EXT2 | MOPT_SET},
1396         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1397          MOPT_NO_EXT2 | MOPT_CLEAR},
1398         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1399         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1400         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1401         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1402         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1403         {Opt_commit, 0, MOPT_GTE0},
1404         {Opt_max_batch_time, 0, MOPT_GTE0},
1405         {Opt_min_batch_time, 0, MOPT_GTE0},
1406         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1407         {Opt_init_itable, 0, MOPT_GTE0},
1408         {Opt_stripe, 0, MOPT_GTE0},
1409         {Opt_resuid, 0, MOPT_GTE0},
1410         {Opt_resgid, 0, MOPT_GTE0},
1411         {Opt_journal_dev, 0, MOPT_GTE0},
1412         {Opt_journal_path, 0, MOPT_STRING},
1413         {Opt_journal_ioprio, 0, MOPT_GTE0},
1414         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1415         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1416         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1417          MOPT_NO_EXT2 | MOPT_DATAJ},
1418         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1419         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1420 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1421         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1422         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1423 #else
1424         {Opt_acl, 0, MOPT_NOSUPPORT},
1425         {Opt_noacl, 0, MOPT_NOSUPPORT},
1426 #endif
1427         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1428         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1429         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1430         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1431                                                         MOPT_SET | MOPT_Q},
1432         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1433                                                         MOPT_SET | MOPT_Q},
1434         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1435                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1436         {Opt_usrjquota, 0, MOPT_Q},
1437         {Opt_grpjquota, 0, MOPT_Q},
1438         {Opt_offusrjquota, 0, MOPT_Q},
1439         {Opt_offgrpjquota, 0, MOPT_Q},
1440         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1441         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1442         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1443         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1444         {Opt_err, 0, 0}
1445 };
1446
1447 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1448                             substring_t *args, unsigned long *journal_devnum,
1449                             unsigned int *journal_ioprio, int is_remount)
1450 {
1451         struct ext4_sb_info *sbi = EXT4_SB(sb);
1452         const struct mount_opts *m;
1453         kuid_t uid;
1454         kgid_t gid;
1455         int arg = 0;
1456
1457 #ifdef CONFIG_QUOTA
1458         if (token == Opt_usrjquota)
1459                 return set_qf_name(sb, USRQUOTA, &args[0]);
1460         else if (token == Opt_grpjquota)
1461                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1462         else if (token == Opt_offusrjquota)
1463                 return clear_qf_name(sb, USRQUOTA);
1464         else if (token == Opt_offgrpjquota)
1465                 return clear_qf_name(sb, GRPQUOTA);
1466 #endif
1467         switch (token) {
1468         case Opt_noacl:
1469         case Opt_nouser_xattr:
1470                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1471                 break;
1472         case Opt_sb:
1473                 return 1;       /* handled by get_sb_block() */
1474         case Opt_removed:
1475                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1476                 return 1;
1477         case Opt_abort:
1478                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1479                 return 1;
1480         case Opt_i_version:
1481                 sb->s_flags |= MS_I_VERSION;
1482                 return 1;
1483         }
1484
1485         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1486                 if (token == m->token)
1487                         break;
1488
1489         if (m->token == Opt_err) {
1490                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1491                          "or missing value", opt);
1492                 return -1;
1493         }
1494
1495         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1496                 ext4_msg(sb, KERN_ERR,
1497                          "Mount option \"%s\" incompatible with ext2", opt);
1498                 return -1;
1499         }
1500         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1501                 ext4_msg(sb, KERN_ERR,
1502                          "Mount option \"%s\" incompatible with ext3", opt);
1503                 return -1;
1504         }
1505
1506         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1507                 return -1;
1508         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1509                 return -1;
1510         if (m->flags & MOPT_EXPLICIT)
1511                 set_opt2(sb, EXPLICIT_DELALLOC);
1512         if (m->flags & MOPT_CLEAR_ERR)
1513                 clear_opt(sb, ERRORS_MASK);
1514         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1515                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1516                          "options when quota turned on");
1517                 return -1;
1518         }
1519
1520         if (m->flags & MOPT_NOSUPPORT) {
1521                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1522         } else if (token == Opt_commit) {
1523                 if (arg == 0)
1524                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1525                 sbi->s_commit_interval = HZ * arg;
1526         } else if (token == Opt_max_batch_time) {
1527                 if (arg == 0)
1528                         arg = EXT4_DEF_MAX_BATCH_TIME;
1529                 sbi->s_max_batch_time = arg;
1530         } else if (token == Opt_min_batch_time) {
1531                 sbi->s_min_batch_time = arg;
1532         } else if (token == Opt_inode_readahead_blks) {
1533                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1534                         ext4_msg(sb, KERN_ERR,
1535                                  "EXT4-fs: inode_readahead_blks must be "
1536                                  "0 or a power of 2 smaller than 2^31");
1537                         return -1;
1538                 }
1539                 sbi->s_inode_readahead_blks = arg;
1540         } else if (token == Opt_init_itable) {
1541                 set_opt(sb, INIT_INODE_TABLE);
1542                 if (!args->from)
1543                         arg = EXT4_DEF_LI_WAIT_MULT;
1544                 sbi->s_li_wait_mult = arg;
1545         } else if (token == Opt_max_dir_size_kb) {
1546                 sbi->s_max_dir_size_kb = arg;
1547         } else if (token == Opt_stripe) {
1548                 sbi->s_stripe = arg;
1549         } else if (token == Opt_resuid) {
1550                 uid = make_kuid(current_user_ns(), arg);
1551                 if (!uid_valid(uid)) {
1552                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1553                         return -1;
1554                 }
1555                 sbi->s_resuid = uid;
1556         } else if (token == Opt_resgid) {
1557                 gid = make_kgid(current_user_ns(), arg);
1558                 if (!gid_valid(gid)) {
1559                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1560                         return -1;
1561                 }
1562                 sbi->s_resgid = gid;
1563         } else if (token == Opt_journal_dev) {
1564                 if (is_remount) {
1565                         ext4_msg(sb, KERN_ERR,
1566                                  "Cannot specify journal on remount");
1567                         return -1;
1568                 }
1569                 *journal_devnum = arg;
1570         } else if (token == Opt_journal_path) {
1571                 char *journal_path;
1572                 struct inode *journal_inode;
1573                 struct path path;
1574                 int error;
1575
1576                 if (is_remount) {
1577                         ext4_msg(sb, KERN_ERR,
1578                                  "Cannot specify journal on remount");
1579                         return -1;
1580                 }
1581                 journal_path = match_strdup(&args[0]);
1582                 if (!journal_path) {
1583                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1584                                 "journal device string");
1585                         return -1;
1586                 }
1587
1588                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1589                 if (error) {
1590                         ext4_msg(sb, KERN_ERR, "error: could not find "
1591                                 "journal device path: error %d", error);
1592                         kfree(journal_path);
1593                         return -1;
1594                 }
1595
1596                 journal_inode = path.dentry->d_inode;
1597                 if (!S_ISBLK(journal_inode->i_mode)) {
1598                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1599                                 "is not a block device", journal_path);
1600                         path_put(&path);
1601                         kfree(journal_path);
1602                         return -1;
1603                 }
1604
1605                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1606                 path_put(&path);
1607                 kfree(journal_path);
1608         } else if (token == Opt_journal_ioprio) {
1609                 if (arg > 7) {
1610                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1611                                  " (must be 0-7)");
1612                         return -1;
1613                 }
1614                 *journal_ioprio =
1615                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1616         } else if (m->flags & MOPT_DATAJ) {
1617                 if (is_remount) {
1618                         if (!sbi->s_journal)
1619                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1620                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1621                                 ext4_msg(sb, KERN_ERR,
1622                                          "Cannot change data mode on remount");
1623                                 return -1;
1624                         }
1625                 } else {
1626                         clear_opt(sb, DATA_FLAGS);
1627                         sbi->s_mount_opt |= m->mount_opt;
1628                 }
1629 #ifdef CONFIG_QUOTA
1630         } else if (m->flags & MOPT_QFMT) {
1631                 if (sb_any_quota_loaded(sb) &&
1632                     sbi->s_jquota_fmt != m->mount_opt) {
1633                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1634                                  "quota options when quota turned on");
1635                         return -1;
1636                 }
1637                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
1638                                                EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1639                         ext4_msg(sb, KERN_ERR,
1640                                  "Cannot set journaled quota options "
1641                                  "when QUOTA feature is enabled");
1642                         return -1;
1643                 }
1644                 sbi->s_jquota_fmt = m->mount_opt;
1645 #endif
1646         } else {
1647                 if (!args->from)
1648                         arg = 1;
1649                 if (m->flags & MOPT_CLEAR)
1650                         arg = !arg;
1651                 else if (unlikely(!(m->flags & MOPT_SET))) {
1652                         ext4_msg(sb, KERN_WARNING,
1653                                  "buggy handling of option %s", opt);
1654                         WARN_ON(1);
1655                         return -1;
1656                 }
1657                 if (arg != 0)
1658                         sbi->s_mount_opt |= m->mount_opt;
1659                 else
1660                         sbi->s_mount_opt &= ~m->mount_opt;
1661         }
1662         return 1;
1663 }
1664
1665 static int parse_options(char *options, struct super_block *sb,
1666                          unsigned long *journal_devnum,
1667                          unsigned int *journal_ioprio,
1668                          int is_remount)
1669 {
1670         struct ext4_sb_info *sbi = EXT4_SB(sb);
1671         char *p;
1672         substring_t args[MAX_OPT_ARGS];
1673         int token;
1674
1675         if (!options)
1676                 return 1;
1677
1678         while ((p = strsep(&options, ",")) != NULL) {
1679                 if (!*p)
1680                         continue;
1681                 /*
1682                  * Initialize args struct so we know whether arg was
1683                  * found; some options take optional arguments.
1684                  */
1685                 args[0].to = args[0].from = NULL;
1686                 token = match_token(p, tokens, args);
1687                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1688                                      journal_ioprio, is_remount) < 0)
1689                         return 0;
1690         }
1691 #ifdef CONFIG_QUOTA
1692         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
1693             (test_opt(sb, USRQUOTA) || test_opt(sb, GRPQUOTA))) {
1694                 ext4_msg(sb, KERN_ERR, "Cannot set quota options when QUOTA "
1695                          "feature is enabled");
1696                 return 0;
1697         }
1698         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1699                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1700                         clear_opt(sb, USRQUOTA);
1701
1702                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1703                         clear_opt(sb, GRPQUOTA);
1704
1705                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1706                         ext4_msg(sb, KERN_ERR, "old and new quota "
1707                                         "format mixing");
1708                         return 0;
1709                 }
1710
1711                 if (!sbi->s_jquota_fmt) {
1712                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1713                                         "not specified");
1714                         return 0;
1715                 }
1716         } else {
1717                 if (sbi->s_jquota_fmt) {
1718                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1719                                         "specified with no journaling "
1720                                         "enabled");
1721                         return 0;
1722                 }
1723         }
1724 #endif
1725         if (test_opt(sb, DIOREAD_NOLOCK)) {
1726                 int blocksize =
1727                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1728
1729                 if (blocksize < PAGE_CACHE_SIZE) {
1730                         ext4_msg(sb, KERN_ERR, "can't mount with "
1731                                  "dioread_nolock if block size != PAGE_SIZE");
1732                         return 0;
1733                 }
1734         }
1735         return 1;
1736 }
1737
1738 static inline void ext4_show_quota_options(struct seq_file *seq,
1739                                            struct super_block *sb)
1740 {
1741 #if defined(CONFIG_QUOTA)
1742         struct ext4_sb_info *sbi = EXT4_SB(sb);
1743
1744         if (sbi->s_jquota_fmt) {
1745                 char *fmtname = "";
1746
1747                 switch (sbi->s_jquota_fmt) {
1748                 case QFMT_VFS_OLD:
1749                         fmtname = "vfsold";
1750                         break;
1751                 case QFMT_VFS_V0:
1752                         fmtname = "vfsv0";
1753                         break;
1754                 case QFMT_VFS_V1:
1755                         fmtname = "vfsv1";
1756                         break;
1757                 }
1758                 seq_printf(seq, ",jqfmt=%s", fmtname);
1759         }
1760
1761         if (sbi->s_qf_names[USRQUOTA])
1762                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1763
1764         if (sbi->s_qf_names[GRPQUOTA])
1765                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1766 #endif
1767 }
1768
1769 static const char *token2str(int token)
1770 {
1771         const struct match_token *t;
1772
1773         for (t = tokens; t->token != Opt_err; t++)
1774                 if (t->token == token && !strchr(t->pattern, '='))
1775                         break;
1776         return t->pattern;
1777 }
1778
1779 /*
1780  * Show an option if
1781  *  - it's set to a non-default value OR
1782  *  - if the per-sb default is different from the global default
1783  */
1784 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1785                               int nodefs)
1786 {
1787         struct ext4_sb_info *sbi = EXT4_SB(sb);
1788         struct ext4_super_block *es = sbi->s_es;
1789         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1790         const struct mount_opts *m;
1791         char sep = nodefs ? '\n' : ',';
1792
1793 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1794 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1795
1796         if (sbi->s_sb_block != 1)
1797                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1798
1799         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1800                 int want_set = m->flags & MOPT_SET;
1801                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1802                     (m->flags & MOPT_CLEAR_ERR))
1803                         continue;
1804                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1805                         continue; /* skip if same as the default */
1806                 if ((want_set &&
1807                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1808                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1809                         continue; /* select Opt_noFoo vs Opt_Foo */
1810                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1811         }
1812
1813         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1814             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1815                 SEQ_OPTS_PRINT("resuid=%u",
1816                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1817         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1818             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1819                 SEQ_OPTS_PRINT("resgid=%u",
1820                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1821         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1822         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1823                 SEQ_OPTS_PUTS("errors=remount-ro");
1824         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1825                 SEQ_OPTS_PUTS("errors=continue");
1826         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1827                 SEQ_OPTS_PUTS("errors=panic");
1828         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1829                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1830         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1831                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1832         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1833                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1834         if (sb->s_flags & MS_I_VERSION)
1835                 SEQ_OPTS_PUTS("i_version");
1836         if (nodefs || sbi->s_stripe)
1837                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1838         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1839                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1840                         SEQ_OPTS_PUTS("data=journal");
1841                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1842                         SEQ_OPTS_PUTS("data=ordered");
1843                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1844                         SEQ_OPTS_PUTS("data=writeback");
1845         }
1846         if (nodefs ||
1847             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1848                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1849                                sbi->s_inode_readahead_blks);
1850
1851         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1852                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1853                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1854         if (nodefs || sbi->s_max_dir_size_kb)
1855                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
1856
1857         ext4_show_quota_options(seq, sb);
1858         return 0;
1859 }
1860
1861 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1862 {
1863         return _ext4_show_options(seq, root->d_sb, 0);
1864 }
1865
1866 static int options_seq_show(struct seq_file *seq, void *offset)
1867 {
1868         struct super_block *sb = seq->private;
1869         int rc;
1870
1871         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1872         rc = _ext4_show_options(seq, sb, 1);
1873         seq_puts(seq, "\n");
1874         return rc;
1875 }
1876
1877 static int options_open_fs(struct inode *inode, struct file *file)
1878 {
1879         return single_open(file, options_seq_show, PDE_DATA(inode));
1880 }
1881
1882 static const struct file_operations ext4_seq_options_fops = {
1883         .owner = THIS_MODULE,
1884         .open = options_open_fs,
1885         .read = seq_read,
1886         .llseek = seq_lseek,
1887         .release = single_release,
1888 };
1889
1890 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1891                             int read_only)
1892 {
1893         struct ext4_sb_info *sbi = EXT4_SB(sb);
1894         int res = 0;
1895
1896         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1897                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1898                          "forcing read-only mode");
1899                 res = MS_RDONLY;
1900         }
1901         if (read_only)
1902                 goto done;
1903         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1904                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1905                          "running e2fsck is recommended");
1906         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1907                 ext4_msg(sb, KERN_WARNING,
1908                          "warning: mounting fs with errors, "
1909                          "running e2fsck is recommended");
1910         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1911                  le16_to_cpu(es->s_mnt_count) >=
1912                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1913                 ext4_msg(sb, KERN_WARNING,
1914                          "warning: maximal mount count reached, "
1915                          "running e2fsck is recommended");
1916         else if (le32_to_cpu(es->s_checkinterval) &&
1917                 (le32_to_cpu(es->s_lastcheck) +
1918                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1919                 ext4_msg(sb, KERN_WARNING,
1920                          "warning: checktime reached, "
1921                          "running e2fsck is recommended");
1922         if (!sbi->s_journal)
1923                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1924         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1925                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1926         le16_add_cpu(&es->s_mnt_count, 1);
1927         es->s_mtime = cpu_to_le32(get_seconds());
1928         ext4_update_dynamic_rev(sb);
1929         if (sbi->s_journal)
1930                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1931
1932         ext4_commit_super(sb, 1);
1933 done:
1934         if (test_opt(sb, DEBUG))
1935                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1936                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1937                         sb->s_blocksize,
1938                         sbi->s_groups_count,
1939                         EXT4_BLOCKS_PER_GROUP(sb),
1940                         EXT4_INODES_PER_GROUP(sb),
1941                         sbi->s_mount_opt, sbi->s_mount_opt2);
1942
1943         cleancache_init_fs(sb);
1944         return res;
1945 }
1946
1947 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
1948 {
1949         struct ext4_sb_info *sbi = EXT4_SB(sb);
1950         struct flex_groups *new_groups;
1951         int size;
1952
1953         if (!sbi->s_log_groups_per_flex)
1954                 return 0;
1955
1956         size = ext4_flex_group(sbi, ngroup - 1) + 1;
1957         if (size <= sbi->s_flex_groups_allocated)
1958                 return 0;
1959
1960         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
1961         new_groups = ext4_kvzalloc(size, GFP_KERNEL);
1962         if (!new_groups) {
1963                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
1964                          size / (int) sizeof(struct flex_groups));
1965                 return -ENOMEM;
1966         }
1967
1968         if (sbi->s_flex_groups) {
1969                 memcpy(new_groups, sbi->s_flex_groups,
1970                        (sbi->s_flex_groups_allocated *
1971                         sizeof(struct flex_groups)));
1972                 ext4_kvfree(sbi->s_flex_groups);
1973         }
1974         sbi->s_flex_groups = new_groups;
1975         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
1976         return 0;
1977 }
1978
1979 static int ext4_fill_flex_info(struct super_block *sb)
1980 {
1981         struct ext4_sb_info *sbi = EXT4_SB(sb);
1982         struct ext4_group_desc *gdp = NULL;
1983         ext4_group_t flex_group;
1984         int i, err;
1985
1986         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1987         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1988                 sbi->s_log_groups_per_flex = 0;
1989                 return 1;
1990         }
1991
1992         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
1993         if (err)
1994                 goto failed;
1995
1996         for (i = 0; i < sbi->s_groups_count; i++) {
1997                 gdp = ext4_get_group_desc(sb, i, NULL);
1998
1999                 flex_group = ext4_flex_group(sbi, i);
2000                 atomic_add(ext4_free_inodes_count(sb, gdp),
2001                            &sbi->s_flex_groups[flex_group].free_inodes);
2002                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2003                              &sbi->s_flex_groups[flex_group].free_clusters);
2004                 atomic_add(ext4_used_dirs_count(sb, gdp),
2005                            &sbi->s_flex_groups[flex_group].used_dirs);
2006         }
2007
2008         return 1;
2009 failed:
2010         return 0;
2011 }
2012
2013 static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
2014                                    struct ext4_group_desc *gdp)
2015 {
2016         int offset;
2017         __u16 crc = 0;
2018         __le32 le_group = cpu_to_le32(block_group);
2019
2020         if ((sbi->s_es->s_feature_ro_compat &
2021              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))) {
2022                 /* Use new metadata_csum algorithm */
2023                 __le16 save_csum;
2024                 __u32 csum32;
2025
2026                 save_csum = gdp->bg_checksum;
2027                 gdp->bg_checksum = 0;
2028                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2029                                      sizeof(le_group));
2030                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
2031                                      sbi->s_desc_size);
2032                 gdp->bg_checksum = save_csum;
2033
2034                 crc = csum32 & 0xFFFF;
2035                 goto out;
2036         }
2037
2038         /* old crc16 code */
2039         offset = offsetof(struct ext4_group_desc, bg_checksum);
2040
2041         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2042         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2043         crc = crc16(crc, (__u8 *)gdp, offset);
2044         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2045         /* for checksum of struct ext4_group_desc do the rest...*/
2046         if ((sbi->s_es->s_feature_incompat &
2047              cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2048             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2049                 crc = crc16(crc, (__u8 *)gdp + offset,
2050                             le16_to_cpu(sbi->s_es->s_desc_size) -
2051                                 offset);
2052
2053 out:
2054         return cpu_to_le16(crc);
2055 }
2056
2057 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2058                                 struct ext4_group_desc *gdp)
2059 {
2060         if (ext4_has_group_desc_csum(sb) &&
2061             (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
2062                                                       block_group, gdp)))
2063                 return 0;
2064
2065         return 1;
2066 }
2067
2068 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2069                               struct ext4_group_desc *gdp)
2070 {
2071         if (!ext4_has_group_desc_csum(sb))
2072                 return;
2073         gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
2074 }
2075
2076 /* Called at mount-time, super-block is locked */
2077 static int ext4_check_descriptors(struct super_block *sb,
2078                                   ext4_group_t *first_not_zeroed)
2079 {
2080         struct ext4_sb_info *sbi = EXT4_SB(sb);
2081         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2082         ext4_fsblk_t last_block;
2083         ext4_fsblk_t block_bitmap;
2084         ext4_fsblk_t inode_bitmap;
2085         ext4_fsblk_t inode_table;
2086         int flexbg_flag = 0;
2087         ext4_group_t i, grp = sbi->s_groups_count;
2088
2089         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2090                 flexbg_flag = 1;
2091
2092         ext4_debug("Checking group descriptors");
2093
2094         for (i = 0; i < sbi->s_groups_count; i++) {
2095                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2096
2097                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2098                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2099                 else
2100                         last_block = first_block +
2101                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2102
2103                 if ((grp == sbi->s_groups_count) &&
2104                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2105                         grp = i;
2106
2107                 block_bitmap = ext4_block_bitmap(sb, gdp);
2108                 if (block_bitmap < first_block || block_bitmap > last_block) {
2109                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2110                                "Block bitmap for group %u not in group "
2111                                "(block %llu)!", i, block_bitmap);
2112                         return 0;
2113                 }
2114                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2115                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2116                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2117                                "Inode bitmap for group %u not in group "
2118                                "(block %llu)!", i, inode_bitmap);
2119                         return 0;
2120                 }
2121                 inode_table = ext4_inode_table(sb, gdp);
2122                 if (inode_table < first_block ||
2123                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2124                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2125                                "Inode table for group %u not in group "
2126                                "(block %llu)!", i, inode_table);
2127                         return 0;
2128                 }
2129                 ext4_lock_group(sb, i);
2130                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2131                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2132                                  "Checksum for group %u failed (%u!=%u)",
2133                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2134                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2135                         if (!(sb->s_flags & MS_RDONLY)) {
2136                                 ext4_unlock_group(sb, i);
2137                                 return 0;
2138                         }
2139                 }
2140                 ext4_unlock_group(sb, i);
2141                 if (!flexbg_flag)
2142                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2143         }
2144         if (NULL != first_not_zeroed)
2145                 *first_not_zeroed = grp;
2146
2147         ext4_free_blocks_count_set(sbi->s_es,
2148                                    EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2149         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2150         return 1;
2151 }
2152
2153 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2154  * the superblock) which were deleted from all directories, but held open by
2155  * a process at the time of a crash.  We walk the list and try to delete these
2156  * inodes at recovery time (only with a read-write filesystem).
2157  *
2158  * In order to keep the orphan inode chain consistent during traversal (in
2159  * case of crash during recovery), we link each inode into the superblock
2160  * orphan list_head and handle it the same way as an inode deletion during
2161  * normal operation (which journals the operations for us).
2162  *
2163  * We only do an iget() and an iput() on each inode, which is very safe if we
2164  * accidentally point at an in-use or already deleted inode.  The worst that
2165  * can happen in this case is that we get a "bit already cleared" message from
2166  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2167  * e2fsck was run on this filesystem, and it must have already done the orphan
2168  * inode cleanup for us, so we can safely abort without any further action.
2169  */
2170 static void ext4_orphan_cleanup(struct super_block *sb,
2171                                 struct ext4_super_block *es)
2172 {
2173         unsigned int s_flags = sb->s_flags;
2174         int nr_orphans = 0, nr_truncates = 0;
2175 #ifdef CONFIG_QUOTA
2176         int i;
2177 #endif
2178         if (!es->s_last_orphan) {
2179                 jbd_debug(4, "no orphan inodes to clean up\n");
2180                 return;
2181         }
2182
2183         if (bdev_read_only(sb->s_bdev)) {
2184                 ext4_msg(sb, KERN_ERR, "write access "
2185                         "unavailable, skipping orphan cleanup");
2186                 return;
2187         }
2188
2189         /* Check if feature set would not allow a r/w mount */
2190         if (!ext4_feature_set_ok(sb, 0)) {
2191                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2192                          "unknown ROCOMPAT features");
2193                 return;
2194         }
2195
2196         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2197                 /* don't clear list on RO mount w/ errors */
2198                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2199                         jbd_debug(1, "Errors on filesystem, "
2200                                   "clearing orphan list.\n");
2201                         es->s_last_orphan = 0;
2202                 }
2203                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2204                 return;
2205         }
2206
2207         if (s_flags & MS_RDONLY) {
2208                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2209                 sb->s_flags &= ~MS_RDONLY;
2210         }
2211 #ifdef CONFIG_QUOTA
2212         /* Needed for iput() to work correctly and not trash data */
2213         sb->s_flags |= MS_ACTIVE;
2214         /* Turn on quotas so that they are updated correctly */
2215         for (i = 0; i < MAXQUOTAS; i++) {
2216                 if (EXT4_SB(sb)->s_qf_names[i]) {
2217                         int ret = ext4_quota_on_mount(sb, i);
2218                         if (ret < 0)
2219                                 ext4_msg(sb, KERN_ERR,
2220                                         "Cannot turn on journaled "
2221                                         "quota: error %d", ret);
2222                 }
2223         }
2224 #endif
2225
2226         while (es->s_last_orphan) {
2227                 struct inode *inode;
2228
2229                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2230                 if (IS_ERR(inode)) {
2231                         es->s_last_orphan = 0;
2232                         break;
2233                 }
2234
2235                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2236                 dquot_initialize(inode);
2237                 if (inode->i_nlink) {
2238                         if (test_opt(sb, DEBUG))
2239                                 ext4_msg(sb, KERN_DEBUG,
2240                                         "%s: truncating inode %lu to %lld bytes",
2241                                         __func__, inode->i_ino, inode->i_size);
2242                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2243                                   inode->i_ino, inode->i_size);
2244                         mutex_lock(&inode->i_mutex);
2245                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2246                         ext4_truncate(inode);
2247                         mutex_unlock(&inode->i_mutex);
2248                         nr_truncates++;
2249                 } else {
2250                         if (test_opt(sb, DEBUG))
2251                                 ext4_msg(sb, KERN_DEBUG,
2252                                         "%s: deleting unreferenced inode %lu",
2253                                         __func__, inode->i_ino);
2254                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2255                                   inode->i_ino);
2256                         nr_orphans++;
2257                 }
2258                 iput(inode);  /* The delete magic happens here! */
2259         }
2260
2261 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2262
2263         if (nr_orphans)
2264                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2265                        PLURAL(nr_orphans));
2266         if (nr_truncates)
2267                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2268                        PLURAL(nr_truncates));
2269 #ifdef CONFIG_QUOTA
2270         /* Turn quotas off */
2271         for (i = 0; i < MAXQUOTAS; i++) {
2272                 if (sb_dqopt(sb)->files[i])
2273                         dquot_quota_off(sb, i);
2274         }
2275 #endif
2276         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2277 }
2278
2279 /*
2280  * Maximal extent format file size.
2281  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2282  * extent format containers, within a sector_t, and within i_blocks
2283  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2284  * so that won't be a limiting factor.
2285  *
2286  * However there is other limiting factor. We do store extents in the form
2287  * of starting block and length, hence the resulting length of the extent
2288  * covering maximum file size must fit into on-disk format containers as
2289  * well. Given that length is always by 1 unit bigger than max unit (because
2290  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2291  *
2292  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2293  */
2294 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2295 {
2296         loff_t res;
2297         loff_t upper_limit = MAX_LFS_FILESIZE;
2298
2299         /* small i_blocks in vfs inode? */
2300         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2301                 /*
2302                  * CONFIG_LBDAF is not enabled implies the inode
2303                  * i_block represent total blocks in 512 bytes
2304                  * 32 == size of vfs inode i_blocks * 8
2305                  */
2306                 upper_limit = (1LL << 32) - 1;
2307
2308                 /* total blocks in file system block size */
2309                 upper_limit >>= (blkbits - 9);
2310                 upper_limit <<= blkbits;
2311         }
2312
2313         /*
2314          * 32-bit extent-start container, ee_block. We lower the maxbytes
2315          * by one fs block, so ee_len can cover the extent of maximum file
2316          * size
2317          */
2318         res = (1LL << 32) - 1;
2319         res <<= blkbits;
2320
2321         /* Sanity check against vm- & vfs- imposed limits */
2322         if (res > upper_limit)
2323                 res = upper_limit;
2324
2325         return res;
2326 }
2327
2328 /*
2329  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2330  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2331  * We need to be 1 filesystem block less than the 2^48 sector limit.
2332  */
2333 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2334 {
2335         loff_t res = EXT4_NDIR_BLOCKS;
2336         int meta_blocks;
2337         loff_t upper_limit;
2338         /* This is calculated to be the largest file size for a dense, block
2339          * mapped file such that the file's total number of 512-byte sectors,
2340          * including data and all indirect blocks, does not exceed (2^48 - 1).
2341          *
2342          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2343          * number of 512-byte sectors of the file.
2344          */
2345
2346         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2347                 /*
2348                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2349                  * the inode i_block field represents total file blocks in
2350                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2351                  */
2352                 upper_limit = (1LL << 32) - 1;
2353
2354                 /* total blocks in file system block size */
2355                 upper_limit >>= (bits - 9);
2356
2357         } else {
2358                 /*
2359                  * We use 48 bit ext4_inode i_blocks
2360                  * With EXT4_HUGE_FILE_FL set the i_blocks
2361                  * represent total number of blocks in
2362                  * file system block size
2363                  */
2364                 upper_limit = (1LL << 48) - 1;
2365
2366         }
2367
2368         /* indirect blocks */
2369         meta_blocks = 1;
2370         /* double indirect blocks */
2371         meta_blocks += 1 + (1LL << (bits-2));
2372         /* tripple indirect blocks */
2373         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2374
2375         upper_limit -= meta_blocks;
2376         upper_limit <<= bits;
2377
2378         res += 1LL << (bits-2);
2379         res += 1LL << (2*(bits-2));
2380         res += 1LL << (3*(bits-2));
2381         res <<= bits;
2382         if (res > upper_limit)
2383                 res = upper_limit;
2384
2385         if (res > MAX_LFS_FILESIZE)
2386                 res = MAX_LFS_FILESIZE;
2387
2388         return res;
2389 }
2390
2391 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2392                                    ext4_fsblk_t logical_sb_block, int nr)
2393 {
2394         struct ext4_sb_info *sbi = EXT4_SB(sb);
2395         ext4_group_t bg, first_meta_bg;
2396         int has_super = 0;
2397
2398         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2399
2400         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2401             nr < first_meta_bg)
2402                 return logical_sb_block + nr + 1;
2403         bg = sbi->s_desc_per_block * nr;
2404         if (ext4_bg_has_super(sb, bg))
2405                 has_super = 1;
2406
2407         return (has_super + ext4_group_first_block_no(sb, bg));
2408 }
2409
2410 /**
2411  * ext4_get_stripe_size: Get the stripe size.
2412  * @sbi: In memory super block info
2413  *
2414  * If we have specified it via mount option, then
2415  * use the mount option value. If the value specified at mount time is
2416  * greater than the blocks per group use the super block value.
2417  * If the super block value is greater than blocks per group return 0.
2418  * Allocator needs it be less than blocks per group.
2419  *
2420  */
2421 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2422 {
2423         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2424         unsigned long stripe_width =
2425                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2426         int ret;
2427
2428         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2429                 ret = sbi->s_stripe;
2430         else if (stripe_width <= sbi->s_blocks_per_group)
2431                 ret = stripe_width;
2432         else if (stride <= sbi->s_blocks_per_group)
2433                 ret = stride;
2434         else
2435                 ret = 0;
2436
2437         /*
2438          * If the stripe width is 1, this makes no sense and
2439          * we set it to 0 to turn off stripe handling code.
2440          */
2441         if (ret <= 1)
2442                 ret = 0;
2443
2444         return ret;
2445 }
2446
2447 /* sysfs supprt */
2448
2449 struct ext4_attr {
2450         struct attribute attr;
2451         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2452         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2453                          const char *, size_t);
2454         union {
2455                 int offset;
2456                 int deprecated_val;
2457         } u;
2458 };
2459
2460 static int parse_strtoull(const char *buf,
2461                 unsigned long long max, unsigned long long *value)
2462 {
2463         int ret;
2464
2465         ret = kstrtoull(skip_spaces(buf), 0, value);
2466         if (!ret && *value > max)
2467                 ret = -EINVAL;
2468         return ret;
2469 }
2470
2471 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2472                                               struct ext4_sb_info *sbi,
2473                                               char *buf)
2474 {
2475         return snprintf(buf, PAGE_SIZE, "%llu\n",
2476                 (s64) EXT4_C2B(sbi,
2477                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2478 }
2479
2480 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2481                                          struct ext4_sb_info *sbi, char *buf)
2482 {
2483         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2484
2485         if (!sb->s_bdev->bd_part)
2486                 return snprintf(buf, PAGE_SIZE, "0\n");
2487         return snprintf(buf, PAGE_SIZE, "%lu\n",
2488                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2489                          sbi->s_sectors_written_start) >> 1);
2490 }
2491
2492 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2493                                           struct ext4_sb_info *sbi, char *buf)
2494 {
2495         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2496
2497         if (!sb->s_bdev->bd_part)
2498                 return snprintf(buf, PAGE_SIZE, "0\n");
2499         return snprintf(buf, PAGE_SIZE, "%llu\n",
2500                         (unsigned long long)(sbi->s_kbytes_written +
2501                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2502                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2503 }
2504
2505 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2506                                           struct ext4_sb_info *sbi,
2507                                           const char *buf, size_t count)
2508 {
2509         unsigned long t;
2510         int ret;
2511
2512         ret = kstrtoul(skip_spaces(buf), 0, &t);
2513         if (ret)
2514                 return ret;
2515
2516         if (t && (!is_power_of_2(t) || t > 0x40000000))
2517                 return -EINVAL;
2518
2519         sbi->s_inode_readahead_blks = t;
2520         return count;
2521 }
2522
2523 static ssize_t sbi_ui_show(struct ext4_attr *a,
2524                            struct ext4_sb_info *sbi, char *buf)
2525 {
2526         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
2527
2528         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2529 }
2530
2531 static ssize_t sbi_ui_store(struct ext4_attr *a,
2532                             struct ext4_sb_info *sbi,
2533                             const char *buf, size_t count)
2534 {
2535         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
2536         unsigned long t;
2537         int ret;
2538
2539         ret = kstrtoul(skip_spaces(buf), 0, &t);
2540         if (ret)
2541                 return ret;
2542         *ui = t;
2543         return count;
2544 }
2545
2546 static ssize_t reserved_clusters_show(struct ext4_attr *a,
2547                                   struct ext4_sb_info *sbi, char *buf)
2548 {
2549         return snprintf(buf, PAGE_SIZE, "%llu\n",
2550                 (unsigned long long) atomic64_read(&sbi->s_resv_clusters));
2551 }
2552
2553 static ssize_t reserved_clusters_store(struct ext4_attr *a,
2554                                    struct ext4_sb_info *sbi,
2555                                    const char *buf, size_t count)
2556 {
2557         unsigned long long val;
2558         int ret;
2559
2560         if (parse_strtoull(buf, -1ULL, &val))
2561                 return -EINVAL;
2562         ret = ext4_reserve_clusters(sbi, val);
2563
2564         return ret ? ret : count;
2565 }
2566
2567 static ssize_t trigger_test_error(struct ext4_attr *a,
2568                                   struct ext4_sb_info *sbi,
2569                                   const char *buf, size_t count)
2570 {
2571         int len = count;
2572
2573         if (!capable(CAP_SYS_ADMIN))
2574                 return -EPERM;
2575
2576         if (len && buf[len-1] == '\n')
2577                 len--;
2578
2579         if (len)
2580                 ext4_error(sbi->s_sb, "%.*s", len, buf);
2581         return count;
2582 }
2583
2584 static ssize_t sbi_deprecated_show(struct ext4_attr *a,
2585                                    struct ext4_sb_info *sbi, char *buf)
2586 {
2587         return snprintf(buf, PAGE_SIZE, "%d\n", a->u.deprecated_val);
2588 }
2589
2590 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2591 static struct ext4_attr ext4_attr_##_name = {                   \
2592         .attr = {.name = __stringify(_name), .mode = _mode },   \
2593         .show   = _show,                                        \
2594         .store  = _store,                                       \
2595         .u = {                                                  \
2596                 .offset = offsetof(struct ext4_sb_info, _elname),\
2597         },                                                      \
2598 }
2599 #define EXT4_ATTR(name, mode, show, store) \
2600 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2601
2602 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2603 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2604 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2605 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2606         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2607 #define ATTR_LIST(name) &ext4_attr_##name.attr
2608 #define EXT4_DEPRECATED_ATTR(_name, _val)       \
2609 static struct ext4_attr ext4_attr_##_name = {                   \
2610         .attr = {.name = __stringify(_name), .mode = 0444 },    \
2611         .show   = sbi_deprecated_show,                          \
2612         .u = {                                                  \
2613                 .deprecated_val = _val,                         \
2614         },                                                      \
2615 }
2616
2617 EXT4_RO_ATTR(delayed_allocation_blocks);
2618 EXT4_RO_ATTR(session_write_kbytes);
2619 EXT4_RO_ATTR(lifetime_write_kbytes);
2620 EXT4_RW_ATTR(reserved_clusters);
2621 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2622                  inode_readahead_blks_store, s_inode_readahead_blks);
2623 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2624 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2625 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2626 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2627 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2628 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2629 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2630 EXT4_DEPRECATED_ATTR(max_writeback_mb_bump, 128);
2631 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
2632 EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error);
2633 EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
2634 EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst);
2635 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
2636 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
2637 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
2638 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
2639
2640 static struct attribute *ext4_attrs[] = {
2641         ATTR_LIST(delayed_allocation_blocks),
2642         ATTR_LIST(session_write_kbytes),
2643         ATTR_LIST(lifetime_write_kbytes),
2644         ATTR_LIST(reserved_clusters),
2645         ATTR_LIST(inode_readahead_blks),
2646         ATTR_LIST(inode_goal),
2647         ATTR_LIST(mb_stats),
2648         ATTR_LIST(mb_max_to_scan),
2649         ATTR_LIST(mb_min_to_scan),
2650         ATTR_LIST(mb_order2_req),
2651         ATTR_LIST(mb_stream_req),
2652         ATTR_LIST(mb_group_prealloc),
2653         ATTR_LIST(max_writeback_mb_bump),
2654         ATTR_LIST(extent_max_zeroout_kb),
2655         ATTR_LIST(trigger_fs_error),
2656         ATTR_LIST(err_ratelimit_interval_ms),
2657         ATTR_LIST(err_ratelimit_burst),
2658         ATTR_LIST(warning_ratelimit_interval_ms),
2659         ATTR_LIST(warning_ratelimit_burst),
2660         ATTR_LIST(msg_ratelimit_interval_ms),
2661         ATTR_LIST(msg_ratelimit_burst),
2662         NULL,
2663 };
2664
2665 /* Features this copy of ext4 supports */
2666 EXT4_INFO_ATTR(lazy_itable_init);
2667 EXT4_INFO_ATTR(batched_discard);
2668 EXT4_INFO_ATTR(meta_bg_resize);
2669
2670 static struct attribute *ext4_feat_attrs[] = {
2671         ATTR_LIST(lazy_itable_init),
2672         ATTR_LIST(batched_discard),
2673         ATTR_LIST(meta_bg_resize),
2674         NULL,
2675 };
2676
2677 static ssize_t ext4_attr_show(struct kobject *kobj,
2678                               struct attribute *attr, char *buf)
2679 {
2680         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2681                                                 s_kobj);
2682         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2683
2684         return a->show ? a->show(a, sbi, buf) : 0;
2685 }
2686
2687 static ssize_t ext4_attr_store(struct kobject *kobj,
2688                                struct attribute *attr,
2689                                const char *buf, size_t len)
2690 {
2691         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2692                                                 s_kobj);
2693         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2694
2695         return a->store ? a->store(a, sbi, buf, len) : 0;
2696 }
2697
2698 static void ext4_sb_release(struct kobject *kobj)
2699 {
2700         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2701                                                 s_kobj);
2702         complete(&sbi->s_kobj_unregister);
2703 }
2704
2705 static const struct sysfs_ops ext4_attr_ops = {
2706         .show   = ext4_attr_show,
2707         .store  = ext4_attr_store,
2708 };
2709
2710 static struct kobj_type ext4_ktype = {
2711         .default_attrs  = ext4_attrs,
2712         .sysfs_ops      = &ext4_attr_ops,
2713         .release        = ext4_sb_release,
2714 };
2715
2716 static void ext4_feat_release(struct kobject *kobj)
2717 {
2718         complete(&ext4_feat->f_kobj_unregister);
2719 }
2720
2721 static struct kobj_type ext4_feat_ktype = {
2722         .default_attrs  = ext4_feat_attrs,
2723         .sysfs_ops      = &ext4_attr_ops,
2724         .release        = ext4_feat_release,
2725 };
2726
2727 /*
2728  * Check whether this filesystem can be mounted based on
2729  * the features present and the RDONLY/RDWR mount requested.
2730  * Returns 1 if this filesystem can be mounted as requested,
2731  * 0 if it cannot be.
2732  */
2733 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2734 {
2735         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2736                 ext4_msg(sb, KERN_ERR,
2737                         "Couldn't mount because of "
2738                         "unsupported optional features (%x)",
2739                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2740                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2741                 return 0;
2742         }
2743
2744         if (readonly)
2745                 return 1;
2746
2747         /* Check that feature set is OK for a read-write mount */
2748         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2749                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2750                          "unsupported optional features (%x)",
2751                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2752                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2753                 return 0;
2754         }
2755         /*
2756          * Large file size enabled file system can only be mounted
2757          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2758          */
2759         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2760                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2761                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2762                                  "cannot be mounted RDWR without "
2763                                  "CONFIG_LBDAF");
2764                         return 0;
2765                 }
2766         }
2767         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2768             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2769                 ext4_msg(sb, KERN_ERR,
2770                          "Can't support bigalloc feature without "
2771                          "extents feature\n");
2772                 return 0;
2773         }
2774
2775 #ifndef CONFIG_QUOTA
2776         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
2777             !readonly) {
2778                 ext4_msg(sb, KERN_ERR,
2779                          "Filesystem with quota feature cannot be mounted RDWR "
2780                          "without CONFIG_QUOTA");
2781                 return 0;
2782         }
2783 #endif  /* CONFIG_QUOTA */
2784         return 1;
2785 }
2786
2787 /*
2788  * This function is called once a day if we have errors logged
2789  * on the file system
2790  */
2791 static void print_daily_error_info(unsigned long arg)
2792 {
2793         struct super_block *sb = (struct super_block *) arg;
2794         struct ext4_sb_info *sbi;
2795         struct ext4_super_block *es;
2796
2797         sbi = EXT4_SB(sb);
2798         es = sbi->s_es;
2799
2800         if (es->s_error_count)
2801                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2802                          le32_to_cpu(es->s_error_count));
2803         if (es->s_first_error_time) {
2804                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2805                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2806                        (int) sizeof(es->s_first_error_func),
2807                        es->s_first_error_func,
2808                        le32_to_cpu(es->s_first_error_line));
2809                 if (es->s_first_error_ino)
2810                         printk(": inode %u",
2811                                le32_to_cpu(es->s_first_error_ino));
2812                 if (es->s_first_error_block)
2813                         printk(": block %llu", (unsigned long long)
2814                                le64_to_cpu(es->s_first_error_block));
2815                 printk("\n");
2816         }
2817         if (es->s_last_error_time) {
2818                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2819                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2820                        (int) sizeof(es->s_last_error_func),
2821                        es->s_last_error_func,
2822                        le32_to_cpu(es->s_last_error_line));
2823                 if (es->s_last_error_ino)
2824                         printk(": inode %u",
2825                                le32_to_cpu(es->s_last_error_ino));
2826                 if (es->s_last_error_block)
2827                         printk(": block %llu", (unsigned long long)
2828                                le64_to_cpu(es->s_last_error_block));
2829                 printk("\n");
2830         }
2831         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2832 }
2833
2834 /* Find next suitable group and run ext4_init_inode_table */
2835 static int ext4_run_li_request(struct ext4_li_request *elr)
2836 {
2837         struct ext4_group_desc *gdp = NULL;
2838         ext4_group_t group, ngroups;
2839         struct super_block *sb;
2840         unsigned long timeout = 0;
2841         int ret = 0;
2842
2843         sb = elr->lr_super;
2844         ngroups = EXT4_SB(sb)->s_groups_count;
2845
2846         sb_start_write(sb);
2847         for (group = elr->lr_next_group; group < ngroups; group++) {
2848                 gdp = ext4_get_group_desc(sb, group, NULL);
2849                 if (!gdp) {
2850                         ret = 1;
2851                         break;
2852                 }
2853
2854                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2855                         break;
2856         }
2857
2858         if (group >= ngroups)
2859                 ret = 1;
2860
2861         if (!ret) {
2862                 timeout = jiffies;
2863                 ret = ext4_init_inode_table(sb, group,
2864                                             elr->lr_timeout ? 0 : 1);
2865                 if (elr->lr_timeout == 0) {
2866                         timeout = (jiffies - timeout) *
2867                                   elr->lr_sbi->s_li_wait_mult;
2868                         elr->lr_timeout = timeout;
2869                 }
2870                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2871                 elr->lr_next_group = group + 1;
2872         }
2873         sb_end_write(sb);
2874
2875         return ret;
2876 }
2877
2878 /*
2879  * Remove lr_request from the list_request and free the
2880  * request structure. Should be called with li_list_mtx held
2881  */
2882 static void ext4_remove_li_request(struct ext4_li_request *elr)
2883 {
2884         struct ext4_sb_info *sbi;
2885
2886         if (!elr)
2887                 return;
2888
2889         sbi = elr->lr_sbi;
2890
2891         list_del(&elr->lr_request);
2892         sbi->s_li_request = NULL;
2893         kfree(elr);
2894 }
2895
2896 static void ext4_unregister_li_request(struct super_block *sb)
2897 {
2898         mutex_lock(&ext4_li_mtx);
2899         if (!ext4_li_info) {
2900                 mutex_unlock(&ext4_li_mtx);
2901                 return;
2902         }
2903
2904         mutex_lock(&ext4_li_info->li_list_mtx);
2905         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2906         mutex_unlock(&ext4_li_info->li_list_mtx);
2907         mutex_unlock(&ext4_li_mtx);
2908 }
2909
2910 static struct task_struct *ext4_lazyinit_task;
2911
2912 /*
2913  * This is the function where ext4lazyinit thread lives. It walks
2914  * through the request list searching for next scheduled filesystem.
2915  * When such a fs is found, run the lazy initialization request
2916  * (ext4_rn_li_request) and keep track of the time spend in this
2917  * function. Based on that time we compute next schedule time of
2918  * the request. When walking through the list is complete, compute
2919  * next waking time and put itself into sleep.
2920  */
2921 static int ext4_lazyinit_thread(void *arg)
2922 {
2923         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2924         struct list_head *pos, *n;
2925         struct ext4_li_request *elr;
2926         unsigned long next_wakeup, cur;
2927
2928         BUG_ON(NULL == eli);
2929
2930 cont_thread:
2931         while (true) {
2932                 next_wakeup = MAX_JIFFY_OFFSET;
2933
2934                 mutex_lock(&eli->li_list_mtx);
2935                 if (list_empty(&eli->li_request_list)) {
2936                         mutex_unlock(&eli->li_list_mtx);
2937                         goto exit_thread;
2938                 }
2939
2940                 list_for_each_safe(pos, n, &eli->li_request_list) {
2941                         elr = list_entry(pos, struct ext4_li_request,
2942                                          lr_request);
2943
2944                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2945                                 if (ext4_run_li_request(elr) != 0) {
2946                                         /* error, remove the lazy_init job */
2947                                         ext4_remove_li_request(elr);
2948                                         continue;
2949                                 }
2950                         }
2951
2952                         if (time_before(elr->lr_next_sched, next_wakeup))
2953                                 next_wakeup = elr->lr_next_sched;
2954                 }
2955                 mutex_unlock(&eli->li_list_mtx);
2956
2957                 try_to_freeze();
2958
2959                 cur = jiffies;
2960                 if ((time_after_eq(cur, next_wakeup)) ||
2961                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2962                         cond_resched();
2963                         continue;
2964                 }
2965
2966                 schedule_timeout_interruptible(next_wakeup - cur);
2967
2968                 if (kthread_should_stop()) {
2969                         ext4_clear_request_list();
2970                         goto exit_thread;
2971                 }
2972         }
2973
2974 exit_thread:
2975         /*
2976          * It looks like the request list is empty, but we need
2977          * to check it under the li_list_mtx lock, to prevent any
2978          * additions into it, and of course we should lock ext4_li_mtx
2979          * to atomically free the list and ext4_li_info, because at
2980          * this point another ext4 filesystem could be registering
2981          * new one.
2982          */
2983         mutex_lock(&ext4_li_mtx);
2984         mutex_lock(&eli->li_list_mtx);
2985         if (!list_empty(&eli->li_request_list)) {
2986                 mutex_unlock(&eli->li_list_mtx);
2987                 mutex_unlock(&ext4_li_mtx);
2988                 goto cont_thread;
2989         }
2990         mutex_unlock(&eli->li_list_mtx);
2991         kfree(ext4_li_info);
2992         ext4_li_info = NULL;
2993         mutex_unlock(&ext4_li_mtx);
2994
2995         return 0;
2996 }
2997
2998 static void ext4_clear_request_list(void)
2999 {
3000         struct list_head *pos, *n;
3001         struct ext4_li_request *elr;
3002
3003         mutex_lock(&ext4_li_info->li_list_mtx);
3004         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3005                 elr = list_entry(pos, struct ext4_li_request,
3006                                  lr_request);
3007                 ext4_remove_li_request(elr);
3008         }
3009         mutex_unlock(&ext4_li_info->li_list_mtx);
3010 }
3011
3012 static int ext4_run_lazyinit_thread(void)
3013 {
3014         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3015                                          ext4_li_info, "ext4lazyinit");
3016         if (IS_ERR(ext4_lazyinit_task)) {
3017                 int err = PTR_ERR(ext4_lazyinit_task);
3018                 ext4_clear_request_list();
3019                 kfree(ext4_li_info);
3020                 ext4_li_info = NULL;
3021                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3022                                  "initialization thread\n",
3023                                  err);
3024                 return err;
3025         }
3026         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3027         return 0;
3028 }
3029
3030 /*
3031  * Check whether it make sense to run itable init. thread or not.
3032  * If there is at least one uninitialized inode table, return
3033  * corresponding group number, else the loop goes through all
3034  * groups and return total number of groups.
3035  */
3036 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3037 {
3038         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3039         struct ext4_group_desc *gdp = NULL;
3040
3041         for (group = 0; group < ngroups; group++) {
3042                 gdp = ext4_get_group_desc(sb, group, NULL);
3043                 if (!gdp)
3044                         continue;
3045
3046                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3047                         break;
3048         }
3049
3050         return group;
3051 }
3052
3053 static int ext4_li_info_new(void)
3054 {
3055         struct ext4_lazy_init *eli = NULL;
3056
3057         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3058         if (!eli)
3059                 return -ENOMEM;
3060
3061         INIT_LIST_HEAD(&eli->li_request_list);
3062         mutex_init(&eli->li_list_mtx);
3063
3064         eli->li_state |= EXT4_LAZYINIT_QUIT;
3065
3066         ext4_li_info = eli;
3067
3068         return 0;
3069 }
3070
3071 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3072                                             ext4_group_t start)
3073 {
3074         struct ext4_sb_info *sbi = EXT4_SB(sb);
3075         struct ext4_li_request *elr;
3076
3077         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3078         if (!elr)
3079                 return NULL;
3080
3081         elr->lr_super = sb;
3082         elr->lr_sbi = sbi;
3083         elr->lr_next_group = start;
3084
3085         /*
3086          * Randomize first schedule time of the request to
3087          * spread the inode table initialization requests
3088          * better.
3089          */
3090         elr->lr_next_sched = jiffies + (prandom_u32() %
3091                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3092         return elr;
3093 }
3094
3095 int ext4_register_li_request(struct super_block *sb,
3096                              ext4_group_t first_not_zeroed)
3097 {
3098         struct ext4_sb_info *sbi = EXT4_SB(sb);
3099         struct ext4_li_request *elr = NULL;
3100         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3101         int ret = 0;
3102
3103         mutex_lock(&ext4_li_mtx);
3104         if (sbi->s_li_request != NULL) {
3105                 /*
3106                  * Reset timeout so it can be computed again, because
3107                  * s_li_wait_mult might have changed.
3108                  */
3109                 sbi->s_li_request->lr_timeout = 0;
3110                 goto out;
3111         }
3112
3113         if (first_not_zeroed == ngroups ||
3114             (sb->s_flags & MS_RDONLY) ||
3115             !test_opt(sb, INIT_INODE_TABLE))
3116                 goto out;
3117
3118         elr = ext4_li_request_new(sb, first_not_zeroed);
3119         if (!elr) {
3120                 ret = -ENOMEM;
3121                 goto out;
3122         }
3123
3124         if (NULL == ext4_li_info) {
3125                 ret = ext4_li_info_new();
3126                 if (ret)
3127                         goto out;
3128         }
3129
3130         mutex_lock(&ext4_li_info->li_list_mtx);
3131         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3132         mutex_unlock(&ext4_li_info->li_list_mtx);
3133
3134         sbi->s_li_request = elr;
3135         /*
3136          * set elr to NULL here since it has been inserted to
3137          * the request_list and the removal and free of it is
3138          * handled by ext4_clear_request_list from now on.
3139          */
3140         elr = NULL;
3141
3142         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3143                 ret = ext4_run_lazyinit_thread();
3144                 if (ret)
3145                         goto out;
3146         }
3147 out:
3148         mutex_unlock(&ext4_li_mtx);
3149         if (ret)
3150                 kfree(elr);
3151         return ret;
3152 }
3153
3154 /*
3155  * We do not need to lock anything since this is called on
3156  * module unload.
3157  */
3158 static void ext4_destroy_lazyinit_thread(void)
3159 {
3160         /*
3161          * If thread exited earlier
3162          * there's nothing to be done.
3163          */
3164         if (!ext4_li_info || !ext4_lazyinit_task)
3165                 return;
3166
3167         kthread_stop(ext4_lazyinit_task);
3168 }
3169
3170 static int set_journal_csum_feature_set(struct super_block *sb)
3171 {
3172         int ret = 1;
3173         int compat, incompat;
3174         struct ext4_sb_info *sbi = EXT4_SB(sb);
3175
3176         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3177                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3178                 /* journal checksum v2 */
3179                 compat = 0;
3180                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V2;
3181         } else {
3182                 /* journal checksum v1 */
3183                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3184                 incompat = 0;
3185         }
3186
3187         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3188                 ret = jbd2_journal_set_features(sbi->s_journal,
3189                                 compat, 0,
3190                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3191                                 incompat);
3192         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3193                 ret = jbd2_journal_set_features(sbi->s_journal,
3194                                 compat, 0,
3195                                 incompat);
3196                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3197                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3198         } else {
3199                 jbd2_journal_clear_features(sbi->s_journal,
3200                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3201                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3202                                 JBD2_FEATURE_INCOMPAT_CSUM_V2);
3203         }
3204
3205         return ret;
3206 }
3207
3208 /*
3209  * Note: calculating the overhead so we can be compatible with
3210  * historical BSD practice is quite difficult in the face of
3211  * clusters/bigalloc.  This is because multiple metadata blocks from
3212  * different block group can end up in the same allocation cluster.
3213  * Calculating the exact overhead in the face of clustered allocation
3214  * requires either O(all block bitmaps) in memory or O(number of block
3215  * groups**2) in time.  We will still calculate the superblock for
3216  * older file systems --- and if we come across with a bigalloc file
3217  * system with zero in s_overhead_clusters the estimate will be close to
3218  * correct especially for very large cluster sizes --- but for newer
3219  * file systems, it's better to calculate this figure once at mkfs
3220  * time, and store it in the superblock.  If the superblock value is
3221  * present (even for non-bigalloc file systems), we will use it.
3222  */
3223 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3224                           char *buf)
3225 {
3226         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3227         struct ext4_group_desc  *gdp;
3228         ext4_fsblk_t            first_block, last_block, b;
3229         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3230         int                     s, j, count = 0;
3231
3232         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC))
3233                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3234                         sbi->s_itb_per_group + 2);
3235
3236         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3237                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3238         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3239         for (i = 0; i < ngroups; i++) {
3240                 gdp = ext4_get_group_desc(sb, i, NULL);
3241                 b = ext4_block_bitmap(sb, gdp);
3242                 if (b >= first_block && b <= last_block) {
3243                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3244                         count++;
3245                 }
3246                 b = ext4_inode_bitmap(sb, gdp);
3247                 if (b >= first_block && b <= last_block) {
3248                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3249                         count++;
3250                 }
3251                 b = ext4_inode_table(sb, gdp);
3252                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3253                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3254                                 int c = EXT4_B2C(sbi, b - first_block);
3255                                 ext4_set_bit(c, buf);
3256                                 count++;
3257                         }
3258                 if (i != grp)
3259                         continue;
3260                 s = 0;
3261                 if (ext4_bg_has_super(sb, grp)) {
3262                         ext4_set_bit(s++, buf);
3263                         count++;
3264                 }
3265                 for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3266                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3267                         count++;
3268                 }
3269         }
3270         if (!count)
3271                 return 0;
3272         return EXT4_CLUSTERS_PER_GROUP(sb) -
3273                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3274 }
3275
3276 /*
3277  * Compute the overhead and stash it in sbi->s_overhead
3278  */
3279 int ext4_calculate_overhead(struct super_block *sb)
3280 {
3281         struct ext4_sb_info *sbi = EXT4_SB(sb);
3282         struct ext4_super_block *es = sbi->s_es;
3283         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3284         ext4_fsblk_t overhead = 0;
3285         char *buf = (char *) get_zeroed_page(GFP_KERNEL);
3286
3287         if (!buf)
3288                 return -ENOMEM;
3289
3290         /*
3291          * Compute the overhead (FS structures).  This is constant
3292          * for a given filesystem unless the number of block groups
3293          * changes so we cache the previous value until it does.
3294          */
3295
3296         /*
3297          * All of the blocks before first_data_block are overhead
3298          */
3299         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3300
3301         /*
3302          * Add the overhead found in each block group
3303          */
3304         for (i = 0; i < ngroups; i++) {
3305                 int blks;
3306
3307                 blks = count_overhead(sb, i, buf);
3308                 overhead += blks;
3309                 if (blks)
3310                         memset(buf, 0, PAGE_SIZE);
3311                 cond_resched();
3312         }
3313         /* Add the journal blocks as well */
3314         if (sbi->s_journal)
3315                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3316
3317         sbi->s_overhead = overhead;
3318         smp_wmb();
3319         free_page((unsigned long) buf);
3320         return 0;
3321 }
3322
3323
3324 static ext4_fsblk_t ext4_calculate_resv_clusters(struct super_block *sb)
3325 {
3326         ext4_fsblk_t resv_clusters;
3327
3328         /*
3329          * There's no need to reserve anything when we aren't using extents.
3330          * The space estimates are exact, there are no unwritten extents,
3331          * hole punching doesn't need new metadata... This is needed especially
3332          * to keep ext2/3 backward compatibility.
3333          */
3334         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
3335                 return 0;
3336         /*
3337          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3338          * This should cover the situations where we can not afford to run
3339          * out of space like for example punch hole, or converting
3340          * uninitialized extents in delalloc path. In most cases such
3341          * allocation would require 1, or 2 blocks, higher numbers are
3342          * very rare.
3343          */
3344         resv_clusters = ext4_blocks_count(EXT4_SB(sb)->s_es) >>
3345                         EXT4_SB(sb)->s_cluster_bits;
3346
3347         do_div(resv_clusters, 50);
3348         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3349
3350         return resv_clusters;
3351 }
3352
3353
3354 static int ext4_reserve_clusters(struct ext4_sb_info *sbi, ext4_fsblk_t count)
3355 {
3356         ext4_fsblk_t clusters = ext4_blocks_count(sbi->s_es) >>
3357                                 sbi->s_cluster_bits;
3358
3359         if (count >= clusters)
3360                 return -EINVAL;
3361
3362         atomic64_set(&sbi->s_resv_clusters, count);
3363         return 0;
3364 }
3365
3366 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3367 {
3368         char *orig_data = kstrdup(data, GFP_KERNEL);
3369         struct buffer_head *bh;
3370         struct ext4_super_block *es = NULL;
3371         struct ext4_sb_info *sbi;
3372         ext4_fsblk_t block;
3373         ext4_fsblk_t sb_block = get_sb_block(&data);
3374         ext4_fsblk_t logical_sb_block;
3375         unsigned long offset = 0;
3376         unsigned long journal_devnum = 0;
3377         unsigned long def_mount_opts;
3378         struct inode *root;
3379         char *cp;
3380         const char *descr;
3381         int ret = -ENOMEM;
3382         int blocksize, clustersize;
3383         unsigned int db_count;
3384         unsigned int i;
3385         int needs_recovery, has_huge_files, has_bigalloc;
3386         __u64 blocks_count;
3387         int err = 0;
3388         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3389         ext4_group_t first_not_zeroed;
3390
3391         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3392         if (!sbi)
3393                 goto out_free_orig;
3394
3395         sbi->s_blockgroup_lock =
3396                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3397         if (!sbi->s_blockgroup_lock) {
3398                 kfree(sbi);
3399                 goto out_free_orig;
3400         }
3401         sb->s_fs_info = sbi;
3402         sbi->s_sb = sb;
3403         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3404         sbi->s_sb_block = sb_block;
3405         if (sb->s_bdev->bd_part)
3406                 sbi->s_sectors_written_start =
3407                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3408
3409         /* Cleanup superblock name */
3410         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3411                 *cp = '!';
3412
3413         /* -EINVAL is default */
3414         ret = -EINVAL;
3415         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3416         if (!blocksize) {
3417                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3418                 goto out_fail;
3419         }
3420
3421         /*
3422          * The ext4 superblock will not be buffer aligned for other than 1kB
3423          * block sizes.  We need to calculate the offset from buffer start.
3424          */
3425         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3426                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3427                 offset = do_div(logical_sb_block, blocksize);
3428         } else {
3429                 logical_sb_block = sb_block;
3430         }
3431
3432         if (!(bh = sb_bread(sb, logical_sb_block))) {
3433                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3434                 goto out_fail;
3435         }
3436         /*
3437          * Note: s_es must be initialized as soon as possible because
3438          *       some ext4 macro-instructions depend on its value
3439          */
3440         es = (struct ext4_super_block *) (bh->b_data + offset);
3441         sbi->s_es = es;
3442         sb->s_magic = le16_to_cpu(es->s_magic);
3443         if (sb->s_magic != EXT4_SUPER_MAGIC)
3444                 goto cantfind_ext4;
3445         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3446
3447         /* Warn if metadata_csum and gdt_csum are both set. */
3448         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3449                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
3450             EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
3451                 ext4_warning(sb, KERN_INFO "metadata_csum and uninit_bg are "
3452                              "redundant flags; please run fsck.");
3453
3454         /* Check for a known checksum algorithm */
3455         if (!ext4_verify_csum_type(sb, es)) {
3456                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3457                          "unknown checksum algorithm.");
3458                 silent = 1;
3459                 goto cantfind_ext4;
3460         }
3461
3462         /* Load the checksum driver */
3463         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3464                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3465                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3466                 if (IS_ERR(sbi->s_chksum_driver)) {
3467                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3468                         ret = PTR_ERR(sbi->s_chksum_driver);
3469                         sbi->s_chksum_driver = NULL;
3470                         goto failed_mount;
3471                 }
3472         }
3473
3474         /* Check superblock checksum */
3475         if (!ext4_superblock_csum_verify(sb, es)) {
3476                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3477                          "invalid superblock checksum.  Run e2fsck?");
3478                 silent = 1;
3479                 goto cantfind_ext4;
3480         }
3481
3482         /* Precompute checksum seed for all metadata */
3483         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3484                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
3485                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3486                                                sizeof(es->s_uuid));
3487
3488         /* Set defaults before we parse the mount options */
3489         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3490         set_opt(sb, INIT_INODE_TABLE);
3491         if (def_mount_opts & EXT4_DEFM_DEBUG)
3492                 set_opt(sb, DEBUG);
3493         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3494                 set_opt(sb, GRPID);
3495         if (def_mount_opts & EXT4_DEFM_UID16)
3496                 set_opt(sb, NO_UID32);
3497         /* xattr user namespace & acls are now defaulted on */
3498         set_opt(sb, XATTR_USER);
3499 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3500         set_opt(sb, POSIX_ACL);
3501 #endif
3502         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3503                 set_opt(sb, JOURNAL_DATA);
3504         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3505                 set_opt(sb, ORDERED_DATA);
3506         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3507                 set_opt(sb, WRITEBACK_DATA);
3508
3509         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3510                 set_opt(sb, ERRORS_PANIC);
3511         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3512                 set_opt(sb, ERRORS_CONT);
3513         else
3514                 set_opt(sb, ERRORS_RO);
3515         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3516                 set_opt(sb, BLOCK_VALIDITY);
3517         if (def_mount_opts & EXT4_DEFM_DISCARD)
3518                 set_opt(sb, DISCARD);
3519
3520         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3521         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3522         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3523         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3524         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3525
3526         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3527                 set_opt(sb, BARRIER);
3528
3529         /*
3530          * enable delayed allocation by default
3531          * Use -o nodelalloc to turn it off
3532          */
3533         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3534             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3535                 set_opt(sb, DELALLOC);
3536
3537         /*
3538          * set default s_li_wait_mult for lazyinit, for the case there is
3539          * no mount option specified.
3540          */
3541         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3542
3543         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3544                            &journal_devnum, &journal_ioprio, 0)) {
3545                 ext4_msg(sb, KERN_WARNING,
3546                          "failed to parse options in superblock: %s",
3547                          sbi->s_es->s_mount_opts);
3548         }
3549         sbi->s_def_mount_opt = sbi->s_mount_opt;
3550         if (!parse_options((char *) data, sb, &journal_devnum,
3551                            &journal_ioprio, 0))
3552                 goto failed_mount;
3553
3554         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3555                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3556                             "with data=journal disables delayed "
3557                             "allocation and O_DIRECT support!\n");
3558                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3559                         ext4_msg(sb, KERN_ERR, "can't mount with "
3560                                  "both data=journal and delalloc");
3561                         goto failed_mount;
3562                 }
3563                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3564                         ext4_msg(sb, KERN_ERR, "can't mount with "
3565                                  "both data=journal and dioread_nolock");
3566                         goto failed_mount;
3567                 }
3568                 if (test_opt(sb, DELALLOC))
3569                         clear_opt(sb, DELALLOC);
3570         }
3571
3572         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3573                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3574
3575         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3576             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3577              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3578              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3579                 ext4_msg(sb, KERN_WARNING,
3580                        "feature flags set on rev 0 fs, "
3581                        "running e2fsck is recommended");
3582
3583         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3584                 set_opt2(sb, HURD_COMPAT);
3585                 if (EXT4_HAS_INCOMPAT_FEATURE(sb,
3586                                               EXT4_FEATURE_INCOMPAT_64BIT)) {
3587                         ext4_msg(sb, KERN_ERR,
3588                                  "The Hurd can't support 64-bit file systems");
3589                         goto failed_mount;
3590                 }
3591         }
3592
3593         if (IS_EXT2_SB(sb)) {
3594                 if (ext2_feature_set_ok(sb))
3595                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3596                                  "using the ext4 subsystem");
3597                 else {
3598                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3599                                  "to feature incompatibilities");
3600                         goto failed_mount;
3601                 }
3602         }
3603
3604         if (IS_EXT3_SB(sb)) {
3605                 if (ext3_feature_set_ok(sb))
3606                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3607                                  "using the ext4 subsystem");
3608                 else {
3609                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3610                                  "to feature incompatibilities");
3611                         goto failed_mount;
3612                 }
3613         }
3614
3615         /*
3616          * Check feature flags regardless of the revision level, since we
3617          * previously didn't change the revision level when setting the flags,
3618          * so there is a chance incompat flags are set on a rev 0 filesystem.
3619          */
3620         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3621                 goto failed_mount;
3622
3623         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3624         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3625             blocksize > EXT4_MAX_BLOCK_SIZE) {
3626                 ext4_msg(sb, KERN_ERR,
3627                        "Unsupported filesystem blocksize %d", blocksize);
3628                 goto failed_mount;
3629         }
3630
3631         if (sb->s_blocksize != blocksize) {
3632                 /* Validate the filesystem blocksize */
3633                 if (!sb_set_blocksize(sb, blocksize)) {
3634                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3635                                         blocksize);
3636                         goto failed_mount;
3637                 }
3638
3639                 brelse(bh);
3640                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3641                 offset = do_div(logical_sb_block, blocksize);
3642                 bh = sb_bread(sb, logical_sb_block);
3643                 if (!bh) {
3644                         ext4_msg(sb, KERN_ERR,
3645                                "Can't read superblock on 2nd try");
3646                         goto failed_mount;
3647                 }
3648                 es = (struct ext4_super_block *)(bh->b_data + offset);
3649                 sbi->s_es = es;
3650                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3651                         ext4_msg(sb, KERN_ERR,
3652                                "Magic mismatch, very weird!");
3653                         goto failed_mount;
3654                 }
3655         }
3656
3657         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3658                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3659         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3660                                                       has_huge_files);
3661         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3662
3663         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3664                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3665                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3666         } else {
3667                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3668                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3669                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3670                     (!is_power_of_2(sbi->s_inode_size)) ||
3671                     (sbi->s_inode_size > blocksize)) {
3672                         ext4_msg(sb, KERN_ERR,
3673                                "unsupported inode size: %d",
3674                                sbi->s_inode_size);
3675                         goto failed_mount;
3676                 }
3677                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3678                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3679         }
3680
3681         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3682         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3683                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3684                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3685                     !is_power_of_2(sbi->s_desc_size)) {
3686                         ext4_msg(sb, KERN_ERR,
3687                                "unsupported descriptor size %lu",
3688                                sbi->s_desc_size);
3689                         goto failed_mount;
3690                 }
3691         } else
3692                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3693
3694         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3695         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3696         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3697                 goto cantfind_ext4;
3698
3699         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3700         if (sbi->s_inodes_per_block == 0)
3701                 goto cantfind_ext4;
3702         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3703                                         sbi->s_inodes_per_block;
3704         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3705         sbi->s_sbh = bh;
3706         sbi->s_mount_state = le16_to_cpu(es->s_state);
3707         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3708         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3709
3710         for (i = 0; i < 4; i++)
3711                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3712         sbi->s_def_hash_version = es->s_def_hash_version;
3713         if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX)) {
3714                 i = le32_to_cpu(es->s_flags);
3715                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
3716                         sbi->s_hash_unsigned = 3;
3717                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3718 #ifdef __CHAR_UNSIGNED__
3719                         if (!(sb->s_flags & MS_RDONLY))
3720                                 es->s_flags |=
3721                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3722                         sbi->s_hash_unsigned = 3;
3723 #else
3724                         if (!(sb->s_flags & MS_RDONLY))
3725                                 es->s_flags |=
3726                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3727 #endif
3728                 }
3729         }
3730
3731         /* Handle clustersize */
3732         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3733         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3734                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3735         if (has_bigalloc) {
3736                 if (clustersize < blocksize) {
3737                         ext4_msg(sb, KERN_ERR,
3738                                  "cluster size (%d) smaller than "
3739                                  "block size (%d)", clustersize, blocksize);
3740                         goto failed_mount;
3741                 }
3742                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3743                         le32_to_cpu(es->s_log_block_size);
3744                 sbi->s_clusters_per_group =
3745                         le32_to_cpu(es->s_clusters_per_group);
3746                 if (sbi->s_clusters_per_group > blocksize * 8) {
3747                         ext4_msg(sb, KERN_ERR,
3748                                  "#clusters per group too big: %lu",
3749                                  sbi->s_clusters_per_group);
3750                         goto failed_mount;
3751                 }
3752                 if (sbi->s_blocks_per_group !=
3753                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3754                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3755                                  "clusters per group (%lu) inconsistent",
3756                                  sbi->s_blocks_per_group,
3757                                  sbi->s_clusters_per_group);
3758                         goto failed_mount;
3759                 }
3760         } else {
3761                 if (clustersize != blocksize) {
3762                         ext4_warning(sb, "fragment/cluster size (%d) != "
3763                                      "block size (%d)", clustersize,
3764                                      blocksize);
3765                         clustersize = blocksize;
3766                 }
3767                 if (sbi->s_blocks_per_group > blocksize * 8) {
3768                         ext4_msg(sb, KERN_ERR,
3769                                  "#blocks per group too big: %lu",
3770                                  sbi->s_blocks_per_group);
3771                         goto failed_mount;
3772                 }
3773                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3774                 sbi->s_cluster_bits = 0;
3775         }
3776         sbi->s_cluster_ratio = clustersize / blocksize;
3777
3778         if (sbi->s_inodes_per_group > blocksize * 8) {
3779                 ext4_msg(sb, KERN_ERR,
3780                        "#inodes per group too big: %lu",
3781                        sbi->s_inodes_per_group);
3782                 goto failed_mount;
3783         }
3784
3785         /* Do we have standard group size of clustersize * 8 blocks ? */
3786         if (sbi->s_blocks_per_group == clustersize << 3)
3787                 set_opt2(sb, STD_GROUP_SIZE);
3788
3789         /*
3790          * Test whether we have more sectors than will fit in sector_t,
3791          * and whether the max offset is addressable by the page cache.
3792          */
3793         err = generic_check_addressable(sb->s_blocksize_bits,
3794                                         ext4_blocks_count(es));
3795         if (err) {
3796                 ext4_msg(sb, KERN_ERR, "filesystem"
3797                          " too large to mount safely on this system");
3798                 if (sizeof(sector_t) < 8)
3799                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3800                 goto failed_mount;
3801         }
3802
3803         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3804                 goto cantfind_ext4;
3805
3806         /* check blocks count against device size */
3807         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3808         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3809                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3810                        "exceeds size of device (%llu blocks)",
3811                        ext4_blocks_count(es), blocks_count);
3812                 goto failed_mount;
3813         }
3814
3815         /*
3816          * It makes no sense for the first data block to be beyond the end
3817          * of the filesystem.
3818          */
3819         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3820                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3821                          "block %u is beyond end of filesystem (%llu)",
3822                          le32_to_cpu(es->s_first_data_block),
3823                          ext4_blocks_count(es));
3824                 goto failed_mount;
3825         }
3826         blocks_count = (ext4_blocks_count(es) -
3827                         le32_to_cpu(es->s_first_data_block) +
3828                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3829         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3830         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3831                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3832                        "(block count %llu, first data block %u, "
3833                        "blocks per group %lu)", sbi->s_groups_count,
3834                        ext4_blocks_count(es),
3835                        le32_to_cpu(es->s_first_data_block),
3836                        EXT4_BLOCKS_PER_GROUP(sb));
3837                 goto failed_mount;
3838         }
3839         sbi->s_groups_count = blocks_count;
3840         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3841                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3842         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3843                    EXT4_DESC_PER_BLOCK(sb);
3844         sbi->s_group_desc = ext4_kvmalloc(db_count *
3845                                           sizeof(struct buffer_head *),
3846                                           GFP_KERNEL);
3847         if (sbi->s_group_desc == NULL) {
3848                 ext4_msg(sb, KERN_ERR, "not enough memory");
3849                 ret = -ENOMEM;
3850                 goto failed_mount;
3851         }
3852
3853         if (ext4_proc_root)
3854                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3855
3856         if (sbi->s_proc)
3857                 proc_create_data("options", S_IRUGO, sbi->s_proc,
3858                                  &ext4_seq_options_fops, sb);
3859
3860         bgl_lock_init(sbi->s_blockgroup_lock);
3861
3862         for (i = 0; i < db_count; i++) {
3863                 block = descriptor_loc(sb, logical_sb_block, i);
3864                 sbi->s_group_desc[i] = sb_bread(sb, block);
3865                 if (!sbi->s_group_desc[i]) {
3866                         ext4_msg(sb, KERN_ERR,
3867                                "can't read group descriptor %d", i);
3868                         db_count = i;
3869                         goto failed_mount2;
3870                 }
3871         }
3872         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3873                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3874                 goto failed_mount2;
3875         }
3876         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3877                 if (!ext4_fill_flex_info(sb)) {
3878                         ext4_msg(sb, KERN_ERR,
3879                                "unable to initialize "
3880                                "flex_bg meta info!");
3881                         goto failed_mount2;
3882                 }
3883
3884         sbi->s_gdb_count = db_count;
3885         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3886         spin_lock_init(&sbi->s_next_gen_lock);
3887
3888         init_timer(&sbi->s_err_report);
3889         sbi->s_err_report.function = print_daily_error_info;
3890         sbi->s_err_report.data = (unsigned long) sb;
3891
3892         /* Register extent status tree shrinker */
3893         ext4_es_register_shrinker(sbi);
3894
3895         err = percpu_counter_init(&sbi->s_freeclusters_counter,
3896                         ext4_count_free_clusters(sb));
3897         if (!err) {
3898                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
3899                                 ext4_count_free_inodes(sb));
3900         }
3901         if (!err) {
3902                 err = percpu_counter_init(&sbi->s_dirs_counter,
3903                                 ext4_count_dirs(sb));
3904         }
3905         if (!err) {
3906                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0);
3907         }
3908         if (!err) {
3909                 err = percpu_counter_init(&sbi->s_extent_cache_cnt, 0);
3910         }
3911         if (err) {
3912                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3913                 goto failed_mount3;
3914         }
3915
3916         sbi->s_stripe = ext4_get_stripe_size(sbi);
3917         sbi->s_extent_max_zeroout_kb = 32;
3918
3919         /*
3920          * set up enough so that it can read an inode
3921          */
3922         if (!test_opt(sb, NOLOAD) &&
3923             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3924                 sb->s_op = &ext4_sops;
3925         else
3926                 sb->s_op = &ext4_nojournal_sops;
3927         sb->s_export_op = &ext4_export_ops;
3928         sb->s_xattr = ext4_xattr_handlers;
3929 #ifdef CONFIG_QUOTA
3930         sb->dq_op = &ext4_quota_operations;
3931         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
3932                 sb->s_qcop = &ext4_qctl_sysfile_operations;
3933         else
3934                 sb->s_qcop = &ext4_qctl_operations;
3935 #endif
3936         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3937
3938         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3939         mutex_init(&sbi->s_orphan_lock);
3940
3941         sb->s_root = NULL;
3942
3943         needs_recovery = (es->s_last_orphan != 0 ||
3944                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3945                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3946
3947         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3948             !(sb->s_flags & MS_RDONLY))
3949                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3950                         goto failed_mount3;
3951
3952         /*
3953          * The first inode we look at is the journal inode.  Don't try
3954          * root first: it may be modified in the journal!
3955          */
3956         if (!test_opt(sb, NOLOAD) &&
3957             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3958                 if (ext4_load_journal(sb, es, journal_devnum))
3959                         goto failed_mount3;
3960         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3961               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3962                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3963                        "suppressed and not mounted read-only");
3964                 goto failed_mount_wq;
3965         } else {
3966                 clear_opt(sb, DATA_FLAGS);
3967                 sbi->s_journal = NULL;
3968                 needs_recovery = 0;
3969                 goto no_journal;
3970         }
3971
3972         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) &&
3973             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3974                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3975                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3976                 goto failed_mount_wq;
3977         }
3978
3979         if (!set_journal_csum_feature_set(sb)) {
3980                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
3981                          "feature set");
3982                 goto failed_mount_wq;
3983         }
3984
3985         /* We have now updated the journal if required, so we can
3986          * validate the data journaling mode. */
3987         switch (test_opt(sb, DATA_FLAGS)) {
3988         case 0:
3989                 /* No mode set, assume a default based on the journal
3990                  * capabilities: ORDERED_DATA if the journal can
3991                  * cope, else JOURNAL_DATA
3992                  */
3993                 if (jbd2_journal_check_available_features
3994                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3995                         set_opt(sb, ORDERED_DATA);
3996                 else
3997                         set_opt(sb, JOURNAL_DATA);
3998                 break;
3999
4000         case EXT4_MOUNT_ORDERED_DATA:
4001         case EXT4_MOUNT_WRITEBACK_DATA:
4002                 if (!jbd2_journal_check_available_features
4003                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4004                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4005                                "requested data journaling mode");
4006                         goto failed_mount_wq;
4007                 }
4008         default:
4009                 break;
4010         }
4011         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4012
4013         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4014
4015         /*
4016          * The journal may have updated the bg summary counts, so we
4017          * need to update the global counters.
4018          */
4019         percpu_counter_set(&sbi->s_freeclusters_counter,
4020                            ext4_count_free_clusters(sb));
4021         percpu_counter_set(&sbi->s_freeinodes_counter,
4022                            ext4_count_free_inodes(sb));
4023         percpu_counter_set(&sbi->s_dirs_counter,
4024                            ext4_count_dirs(sb));
4025         percpu_counter_set(&sbi->s_dirtyclusters_counter, 0);
4026
4027 no_journal:
4028         if (ext4_mballoc_ready) {
4029                 sbi->s_mb_cache = ext4_xattr_create_cache(sb->s_id);
4030                 if (!sbi->s_mb_cache) {
4031                         ext4_msg(sb, KERN_ERR, "Failed to create an mb_cache");
4032                         goto failed_mount_wq;
4033                 }
4034         }
4035
4036         /*
4037          * Get the # of file system overhead blocks from the
4038          * superblock if present.
4039          */
4040         if (es->s_overhead_clusters)
4041                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4042         else {
4043                 err = ext4_calculate_overhead(sb);
4044                 if (err)
4045                         goto failed_mount_wq;
4046         }
4047
4048         /*
4049          * The maximum number of concurrent works can be high and
4050          * concurrency isn't really necessary.  Limit it to 1.
4051          */
4052         EXT4_SB(sb)->rsv_conversion_wq =
4053                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4054         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4055                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4056                 ret = -ENOMEM;
4057                 goto failed_mount4;
4058         }
4059
4060         /*
4061          * The jbd2_journal_load will have done any necessary log recovery,
4062          * so we can safely mount the rest of the filesystem now.
4063          */
4064
4065         root = ext4_iget(sb, EXT4_ROOT_INO);
4066         if (IS_ERR(root)) {
4067                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4068                 ret = PTR_ERR(root);
4069                 root = NULL;
4070                 goto failed_mount4;
4071         }
4072         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4073                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4074                 iput(root);
4075                 goto failed_mount4;
4076         }
4077         sb->s_root = d_make_root(root);
4078         if (!sb->s_root) {
4079                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4080                 ret = -ENOMEM;
4081                 goto failed_mount4;
4082         }
4083
4084         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
4085                 sb->s_flags |= MS_RDONLY;
4086
4087         /* determine the minimum size of new large inodes, if present */
4088         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4089                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4090                                                      EXT4_GOOD_OLD_INODE_SIZE;
4091                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
4092                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
4093                         if (sbi->s_want_extra_isize <
4094                             le16_to_cpu(es->s_want_extra_isize))
4095                                 sbi->s_want_extra_isize =
4096                                         le16_to_cpu(es->s_want_extra_isize);
4097                         if (sbi->s_want_extra_isize <
4098                             le16_to_cpu(es->s_min_extra_isize))
4099                                 sbi->s_want_extra_isize =
4100                                         le16_to_cpu(es->s_min_extra_isize);
4101                 }
4102         }
4103         /* Check if enough inode space is available */
4104         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
4105                                                         sbi->s_inode_size) {
4106                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4107                                                        EXT4_GOOD_OLD_INODE_SIZE;
4108                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
4109                          "available");
4110         }
4111
4112         err = ext4_reserve_clusters(sbi, ext4_calculate_resv_clusters(sb));
4113         if (err) {
4114                 ext4_msg(sb, KERN_ERR, "failed to reserve %llu clusters for "
4115                          "reserved pool", ext4_calculate_resv_clusters(sb));
4116                 goto failed_mount4a;
4117         }
4118
4119         err = ext4_setup_system_zone(sb);
4120         if (err) {
4121                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4122                          "zone (%d)", err);
4123                 goto failed_mount4a;
4124         }
4125
4126         ext4_ext_init(sb);
4127         err = ext4_mb_init(sb);
4128         if (err) {
4129                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4130                          err);
4131                 goto failed_mount5;
4132         }
4133
4134         err = ext4_register_li_request(sb, first_not_zeroed);
4135         if (err)
4136                 goto failed_mount6;
4137
4138         sbi->s_kobj.kset = ext4_kset;
4139         init_completion(&sbi->s_kobj_unregister);
4140         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
4141                                    "%s", sb->s_id);
4142         if (err)
4143                 goto failed_mount7;
4144
4145 #ifdef CONFIG_QUOTA
4146         /* Enable quota usage during mount. */
4147         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
4148             !(sb->s_flags & MS_RDONLY)) {
4149                 err = ext4_enable_quotas(sb);
4150                 if (err)
4151                         goto failed_mount8;
4152         }
4153 #endif  /* CONFIG_QUOTA */
4154
4155         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4156         ext4_orphan_cleanup(sb, es);
4157         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4158         if (needs_recovery) {
4159                 ext4_msg(sb, KERN_INFO, "recovery complete");
4160                 ext4_mark_recovery_complete(sb, es);
4161         }
4162         if (EXT4_SB(sb)->s_journal) {
4163                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4164                         descr = " journalled data mode";
4165                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4166                         descr = " ordered data mode";
4167                 else
4168                         descr = " writeback data mode";
4169         } else
4170                 descr = "out journal";
4171
4172         if (test_opt(sb, DISCARD)) {
4173                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4174                 if (!blk_queue_discard(q))
4175                         ext4_msg(sb, KERN_WARNING,
4176                                  "mounting with \"discard\" option, but "
4177                                  "the device does not support discard");
4178         }
4179
4180         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4181                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
4182                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4183
4184         if (es->s_error_count)
4185                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4186
4187         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4188         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4189         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4190         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4191
4192         kfree(orig_data);
4193         return 0;
4194
4195 cantfind_ext4:
4196         if (!silent)
4197                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4198         goto failed_mount;
4199
4200 #ifdef CONFIG_QUOTA
4201 failed_mount8:
4202         kobject_del(&sbi->s_kobj);
4203 #endif
4204 failed_mount7:
4205         ext4_unregister_li_request(sb);
4206 failed_mount6:
4207         ext4_mb_release(sb);
4208 failed_mount5:
4209         ext4_ext_release(sb);
4210         ext4_release_system_zone(sb);
4211 failed_mount4a:
4212         dput(sb->s_root);
4213         sb->s_root = NULL;
4214 failed_mount4:
4215         ext4_msg(sb, KERN_ERR, "mount failed");
4216         if (EXT4_SB(sb)->rsv_conversion_wq)
4217                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4218 failed_mount_wq:
4219         if (sbi->s_journal) {
4220                 jbd2_journal_destroy(sbi->s_journal);
4221                 sbi->s_journal = NULL;
4222         }
4223 failed_mount3:
4224         ext4_es_unregister_shrinker(sbi);
4225         del_timer_sync(&sbi->s_err_report);
4226         if (sbi->s_flex_groups)
4227                 ext4_kvfree(sbi->s_flex_groups);
4228         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4229         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4230         percpu_counter_destroy(&sbi->s_dirs_counter);
4231         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4232         percpu_counter_destroy(&sbi->s_extent_cache_cnt);
4233         if (sbi->s_mmp_tsk)
4234                 kthread_stop(sbi->s_mmp_tsk);
4235 failed_mount2:
4236         for (i = 0; i < db_count; i++)
4237                 brelse(sbi->s_group_desc[i]);
4238         ext4_kvfree(sbi->s_group_desc);
4239 failed_mount:
4240         if (sbi->s_chksum_driver)
4241                 crypto_free_shash(sbi->s_chksum_driver);
4242         if (sbi->s_proc) {
4243                 remove_proc_entry("options", sbi->s_proc);
4244                 remove_proc_entry(sb->s_id, ext4_proc_root);
4245         }
4246 #ifdef CONFIG_QUOTA
4247         for (i = 0; i < MAXQUOTAS; i++)
4248                 kfree(sbi->s_qf_names[i]);
4249 #endif
4250         ext4_blkdev_remove(sbi);
4251         brelse(bh);
4252 out_fail:
4253         sb->s_fs_info = NULL;
4254         kfree(sbi->s_blockgroup_lock);
4255         kfree(sbi);
4256 out_free_orig:
4257         kfree(orig_data);
4258         return err ? err : ret;
4259 }
4260
4261 /*
4262  * Setup any per-fs journal parameters now.  We'll do this both on
4263  * initial mount, once the journal has been initialised but before we've
4264  * done any recovery; and again on any subsequent remount.
4265  */
4266 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4267 {
4268         struct ext4_sb_info *sbi = EXT4_SB(sb);
4269
4270         journal->j_commit_interval = sbi->s_commit_interval;
4271         journal->j_min_batch_time = sbi->s_min_batch_time;
4272         journal->j_max_batch_time = sbi->s_max_batch_time;
4273
4274         write_lock(&journal->j_state_lock);
4275         if (test_opt(sb, BARRIER))
4276                 journal->j_flags |= JBD2_BARRIER;
4277         else
4278                 journal->j_flags &= ~JBD2_BARRIER;
4279         if (test_opt(sb, DATA_ERR_ABORT))
4280                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4281         else
4282                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4283         write_unlock(&journal->j_state_lock);
4284 }
4285
4286 static journal_t *ext4_get_journal(struct super_block *sb,
4287                                    unsigned int journal_inum)
4288 {
4289         struct inode *journal_inode;
4290         journal_t *journal;
4291
4292         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4293
4294         /* First, test for the existence of a valid inode on disk.  Bad
4295          * things happen if we iget() an unused inode, as the subsequent
4296          * iput() will try to delete it. */
4297
4298         journal_inode = ext4_iget(sb, journal_inum);
4299         if (IS_ERR(journal_inode)) {
4300                 ext4_msg(sb, KERN_ERR, "no journal found");
4301                 return NULL;
4302         }
4303         if (!journal_inode->i_nlink) {
4304                 make_bad_inode(journal_inode);
4305                 iput(journal_inode);
4306                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4307                 return NULL;
4308         }
4309
4310         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4311                   journal_inode, journal_inode->i_size);
4312         if (!S_ISREG(journal_inode->i_mode)) {
4313                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4314                 iput(journal_inode);
4315                 return NULL;
4316         }
4317
4318         journal = jbd2_journal_init_inode(journal_inode);
4319         if (!journal) {
4320                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4321                 iput(journal_inode);
4322                 return NULL;
4323         }
4324         journal->j_private = sb;
4325         ext4_init_journal_params(sb, journal);
4326         return journal;
4327 }
4328
4329 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4330                                        dev_t j_dev)
4331 {
4332         struct buffer_head *bh;
4333         journal_t *journal;
4334         ext4_fsblk_t start;
4335         ext4_fsblk_t len;
4336         int hblock, blocksize;
4337         ext4_fsblk_t sb_block;
4338         unsigned long offset;
4339         struct ext4_super_block *es;
4340         struct block_device *bdev;
4341
4342         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4343
4344         bdev = ext4_blkdev_get(j_dev, sb);
4345         if (bdev == NULL)
4346                 return NULL;
4347
4348         blocksize = sb->s_blocksize;
4349         hblock = bdev_logical_block_size(bdev);
4350         if (blocksize < hblock) {
4351                 ext4_msg(sb, KERN_ERR,
4352                         "blocksize too small for journal device");
4353                 goto out_bdev;
4354         }
4355
4356         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4357         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4358         set_blocksize(bdev, blocksize);
4359         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4360                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4361                        "external journal");
4362                 goto out_bdev;
4363         }
4364
4365         es = (struct ext4_super_block *) (bh->b_data + offset);
4366         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4367             !(le32_to_cpu(es->s_feature_incompat) &
4368               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4369                 ext4_msg(sb, KERN_ERR, "external journal has "
4370                                         "bad superblock");
4371                 brelse(bh);
4372                 goto out_bdev;
4373         }
4374
4375         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4376                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4377                 brelse(bh);
4378                 goto out_bdev;
4379         }
4380
4381         len = ext4_blocks_count(es);
4382         start = sb_block + 1;
4383         brelse(bh);     /* we're done with the superblock */
4384
4385         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4386                                         start, len, blocksize);
4387         if (!journal) {
4388                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4389                 goto out_bdev;
4390         }
4391         journal->j_private = sb;
4392         ll_rw_block(READ | REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4393         wait_on_buffer(journal->j_sb_buffer);
4394         if (!buffer_uptodate(journal->j_sb_buffer)) {
4395                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4396                 goto out_journal;
4397         }
4398         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4399                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4400                                         "user (unsupported) - %d",
4401                         be32_to_cpu(journal->j_superblock->s_nr_users));
4402                 goto out_journal;
4403         }
4404         EXT4_SB(sb)->journal_bdev = bdev;
4405         ext4_init_journal_params(sb, journal);
4406         return journal;
4407
4408 out_journal:
4409         jbd2_journal_destroy(journal);
4410 out_bdev:
4411         ext4_blkdev_put(bdev);
4412         return NULL;
4413 }
4414
4415 static int ext4_load_journal(struct super_block *sb,
4416                              struct ext4_super_block *es,
4417                              unsigned long journal_devnum)
4418 {
4419         journal_t *journal;
4420         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4421         dev_t journal_dev;
4422         int err = 0;
4423         int really_read_only;
4424
4425         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4426
4427         if (journal_devnum &&
4428             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4429                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4430                         "numbers have changed");
4431                 journal_dev = new_decode_dev(journal_devnum);
4432         } else
4433                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4434
4435         really_read_only = bdev_read_only(sb->s_bdev);
4436
4437         /*
4438          * Are we loading a blank journal or performing recovery after a
4439          * crash?  For recovery, we need to check in advance whether we
4440          * can get read-write access to the device.
4441          */
4442         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4443                 if (sb->s_flags & MS_RDONLY) {
4444                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4445                                         "required on readonly filesystem");
4446                         if (really_read_only) {
4447                                 ext4_msg(sb, KERN_ERR, "write access "
4448                                         "unavailable, cannot proceed");
4449                                 return -EROFS;
4450                         }
4451                         ext4_msg(sb, KERN_INFO, "write access will "
4452                                "be enabled during recovery");
4453                 }
4454         }
4455
4456         if (journal_inum && journal_dev) {
4457                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4458                        "and inode journals!");
4459                 return -EINVAL;
4460         }
4461
4462         if (journal_inum) {
4463                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4464                         return -EINVAL;
4465         } else {
4466                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4467                         return -EINVAL;
4468         }
4469
4470         if (!(journal->j_flags & JBD2_BARRIER))
4471                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4472
4473         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4474                 err = jbd2_journal_wipe(journal, !really_read_only);
4475         if (!err) {
4476                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4477                 if (save)
4478                         memcpy(save, ((char *) es) +
4479                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4480                 err = jbd2_journal_load(journal);
4481                 if (save)
4482                         memcpy(((char *) es) + EXT4_S_ERR_START,
4483                                save, EXT4_S_ERR_LEN);
4484                 kfree(save);
4485         }
4486
4487         if (err) {
4488                 ext4_msg(sb, KERN_ERR, "error loading journal");
4489                 jbd2_journal_destroy(journal);
4490                 return err;
4491         }
4492
4493         EXT4_SB(sb)->s_journal = journal;
4494         ext4_clear_journal_err(sb, es);
4495
4496         if (!really_read_only && journal_devnum &&
4497             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4498                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4499
4500                 /* Make sure we flush the recovery flag to disk. */
4501                 ext4_commit_super(sb, 1);
4502         }
4503
4504         return 0;
4505 }
4506
4507 static int ext4_commit_super(struct super_block *sb, int sync)
4508 {
4509         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4510         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4511         int error = 0;
4512
4513         if (!sbh || block_device_ejected(sb))
4514                 return error;
4515         if (buffer_write_io_error(sbh)) {
4516                 /*
4517                  * Oh, dear.  A previous attempt to write the
4518                  * superblock failed.  This could happen because the
4519                  * USB device was yanked out.  Or it could happen to
4520                  * be a transient write error and maybe the block will
4521                  * be remapped.  Nothing we can do but to retry the
4522                  * write and hope for the best.
4523                  */
4524                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4525                        "superblock detected");
4526                 clear_buffer_write_io_error(sbh);
4527                 set_buffer_uptodate(sbh);
4528         }
4529         /*
4530          * If the file system is mounted read-only, don't update the
4531          * superblock write time.  This avoids updating the superblock
4532          * write time when we are mounting the root file system
4533          * read/only but we need to replay the journal; at that point,
4534          * for people who are east of GMT and who make their clock
4535          * tick in localtime for Windows bug-for-bug compatibility,
4536          * the clock is set in the future, and this will cause e2fsck
4537          * to complain and force a full file system check.
4538          */
4539         if (!(sb->s_flags & MS_RDONLY))
4540                 es->s_wtime = cpu_to_le32(get_seconds());
4541         if (sb->s_bdev->bd_part)
4542                 es->s_kbytes_written =
4543                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4544                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4545                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4546         else
4547                 es->s_kbytes_written =
4548                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4549         ext4_free_blocks_count_set(es,
4550                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4551                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4552         es->s_free_inodes_count =
4553                 cpu_to_le32(percpu_counter_sum_positive(
4554                                 &EXT4_SB(sb)->s_freeinodes_counter));
4555         BUFFER_TRACE(sbh, "marking dirty");
4556         ext4_superblock_csum_set(sb);
4557         mark_buffer_dirty(sbh);
4558         if (sync) {
4559                 error = sync_dirty_buffer(sbh);
4560                 if (error)
4561                         return error;
4562
4563                 error = buffer_write_io_error(sbh);
4564                 if (error) {
4565                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4566                                "superblock");
4567                         clear_buffer_write_io_error(sbh);
4568                         set_buffer_uptodate(sbh);
4569                 }
4570         }
4571         return error;
4572 }
4573
4574 /*
4575  * Have we just finished recovery?  If so, and if we are mounting (or
4576  * remounting) the filesystem readonly, then we will end up with a
4577  * consistent fs on disk.  Record that fact.
4578  */
4579 static void ext4_mark_recovery_complete(struct super_block *sb,
4580                                         struct ext4_super_block *es)
4581 {
4582         journal_t *journal = EXT4_SB(sb)->s_journal;
4583
4584         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4585                 BUG_ON(journal != NULL);
4586                 return;
4587         }
4588         jbd2_journal_lock_updates(journal);
4589         if (jbd2_journal_flush(journal) < 0)
4590                 goto out;
4591
4592         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4593             sb->s_flags & MS_RDONLY) {
4594                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4595                 ext4_commit_super(sb, 1);
4596         }
4597
4598 out:
4599         jbd2_journal_unlock_updates(journal);
4600 }
4601
4602 /*
4603  * If we are mounting (or read-write remounting) a filesystem whose journal
4604  * has recorded an error from a previous lifetime, move that error to the
4605  * main filesystem now.
4606  */
4607 static void ext4_clear_journal_err(struct super_block *sb,
4608                                    struct ext4_super_block *es)
4609 {
4610         journal_t *journal;
4611         int j_errno;
4612         const char *errstr;
4613
4614         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4615
4616         journal = EXT4_SB(sb)->s_journal;
4617
4618         /*
4619          * Now check for any error status which may have been recorded in the
4620          * journal by a prior ext4_error() or ext4_abort()
4621          */
4622
4623         j_errno = jbd2_journal_errno(journal);
4624         if (j_errno) {
4625                 char nbuf[16];
4626
4627                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4628                 ext4_warning(sb, "Filesystem error recorded "
4629                              "from previous mount: %s", errstr);
4630                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4631
4632                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4633                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4634                 ext4_commit_super(sb, 1);
4635
4636                 jbd2_journal_clear_err(journal);
4637                 jbd2_journal_update_sb_errno(journal);
4638         }
4639 }
4640
4641 /*
4642  * Force the running and committing transactions to commit,
4643  * and wait on the commit.
4644  */
4645 int ext4_force_commit(struct super_block *sb)
4646 {
4647         journal_t *journal;
4648
4649         if (sb->s_flags & MS_RDONLY)
4650                 return 0;
4651
4652         journal = EXT4_SB(sb)->s_journal;
4653         return ext4_journal_force_commit(journal);
4654 }
4655
4656 static int ext4_sync_fs(struct super_block *sb, int wait)
4657 {
4658         int ret = 0;
4659         tid_t target;
4660         bool needs_barrier = false;
4661         struct ext4_sb_info *sbi = EXT4_SB(sb);
4662
4663         trace_ext4_sync_fs(sb, wait);
4664         flush_workqueue(sbi->rsv_conversion_wq);
4665         /*
4666          * Writeback quota in non-journalled quota case - journalled quota has
4667          * no dirty dquots
4668          */
4669         dquot_writeback_dquots(sb, -1);
4670         /*
4671          * Data writeback is possible w/o journal transaction, so barrier must
4672          * being sent at the end of the function. But we can skip it if
4673          * transaction_commit will do it for us.
4674          */
4675         target = jbd2_get_latest_transaction(sbi->s_journal);
4676         if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
4677             !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
4678                 needs_barrier = true;
4679
4680         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4681                 if (wait)
4682                         ret = jbd2_log_wait_commit(sbi->s_journal, target);
4683         }
4684         if (needs_barrier) {
4685                 int err;
4686                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4687                 if (!ret)
4688                         ret = err;
4689         }
4690
4691         return ret;
4692 }
4693
4694 static int ext4_sync_fs_nojournal(struct super_block *sb, int wait)
4695 {
4696         int ret = 0;
4697
4698         trace_ext4_sync_fs(sb, wait);
4699         flush_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4700         dquot_writeback_dquots(sb, -1);
4701         if (wait && test_opt(sb, BARRIER))
4702                 ret = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4703
4704         return ret;
4705 }
4706
4707 /*
4708  * LVM calls this function before a (read-only) snapshot is created.  This
4709  * gives us a chance to flush the journal completely and mark the fs clean.
4710  *
4711  * Note that only this function cannot bring a filesystem to be in a clean
4712  * state independently. It relies on upper layer to stop all data & metadata
4713  * modifications.
4714  */
4715 static int ext4_freeze(struct super_block *sb)
4716 {
4717         int error = 0;
4718         journal_t *journal;
4719
4720         if (sb->s_flags & MS_RDONLY)
4721                 return 0;
4722
4723         journal = EXT4_SB(sb)->s_journal;
4724
4725         /* Now we set up the journal barrier. */
4726         jbd2_journal_lock_updates(journal);
4727
4728         /*
4729          * Don't clear the needs_recovery flag if we failed to flush
4730          * the journal.
4731          */
4732         error = jbd2_journal_flush(journal);
4733         if (error < 0)
4734                 goto out;
4735
4736         /* Journal blocked and flushed, clear needs_recovery flag. */
4737         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4738         error = ext4_commit_super(sb, 1);
4739 out:
4740         /* we rely on upper layer to stop further updates */
4741         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4742         return error;
4743 }
4744
4745 /*
4746  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4747  * flag here, even though the filesystem is not technically dirty yet.
4748  */
4749 static int ext4_unfreeze(struct super_block *sb)
4750 {
4751         if (sb->s_flags & MS_RDONLY)
4752                 return 0;
4753
4754         /* Reset the needs_recovery flag before the fs is unlocked. */
4755         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4756         ext4_commit_super(sb, 1);
4757         return 0;
4758 }
4759
4760 /*
4761  * Structure to save mount options for ext4_remount's benefit
4762  */
4763 struct ext4_mount_options {
4764         unsigned long s_mount_opt;
4765         unsigned long s_mount_opt2;
4766         kuid_t s_resuid;
4767         kgid_t s_resgid;
4768         unsigned long s_commit_interval;
4769         u32 s_min_batch_time, s_max_batch_time;
4770 #ifdef CONFIG_QUOTA
4771         int s_jquota_fmt;
4772         char *s_qf_names[MAXQUOTAS];
4773 #endif
4774 };
4775
4776 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4777 {
4778         struct ext4_super_block *es;
4779         struct ext4_sb_info *sbi = EXT4_SB(sb);
4780         unsigned long old_sb_flags;
4781         struct ext4_mount_options old_opts;
4782         int enable_quota = 0;
4783         ext4_group_t g;
4784         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4785         int err = 0;
4786 #ifdef CONFIG_QUOTA
4787         int i, j;
4788 #endif
4789         char *orig_data = kstrdup(data, GFP_KERNEL);
4790
4791         /* Store the original options */
4792         old_sb_flags = sb->s_flags;
4793         old_opts.s_mount_opt = sbi->s_mount_opt;
4794         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4795         old_opts.s_resuid = sbi->s_resuid;
4796         old_opts.s_resgid = sbi->s_resgid;
4797         old_opts.s_commit_interval = sbi->s_commit_interval;
4798         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4799         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4800 #ifdef CONFIG_QUOTA
4801         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4802         for (i = 0; i < MAXQUOTAS; i++)
4803                 if (sbi->s_qf_names[i]) {
4804                         old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
4805                                                          GFP_KERNEL);
4806                         if (!old_opts.s_qf_names[i]) {
4807                                 for (j = 0; j < i; j++)
4808                                         kfree(old_opts.s_qf_names[j]);
4809                                 kfree(orig_data);
4810                                 return -ENOMEM;
4811                         }
4812                 } else
4813                         old_opts.s_qf_names[i] = NULL;
4814 #endif
4815         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4816                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4817
4818         /*
4819          * Allow the "check" option to be passed as a remount option.
4820          */
4821         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4822                 err = -EINVAL;
4823                 goto restore_opts;
4824         }
4825
4826         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4827                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4828                         ext4_msg(sb, KERN_ERR, "can't mount with "
4829                                  "both data=journal and delalloc");
4830                         err = -EINVAL;
4831                         goto restore_opts;
4832                 }
4833                 if (test_opt(sb, DIOREAD_NOLOCK)) {
4834                         ext4_msg(sb, KERN_ERR, "can't mount with "
4835                                  "both data=journal and dioread_nolock");
4836                         err = -EINVAL;
4837                         goto restore_opts;
4838                 }
4839         }
4840
4841         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4842                 ext4_abort(sb, "Abort forced by user");
4843
4844         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4845                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4846
4847         es = sbi->s_es;
4848
4849         if (sbi->s_journal) {
4850                 ext4_init_journal_params(sb, sbi->s_journal);
4851                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4852         }
4853
4854         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4855                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4856                         err = -EROFS;
4857                         goto restore_opts;
4858                 }
4859
4860                 if (*flags & MS_RDONLY) {
4861                         err = sync_filesystem(sb);
4862                         if (err < 0)
4863                                 goto restore_opts;
4864                         err = dquot_suspend(sb, -1);
4865                         if (err < 0)
4866                                 goto restore_opts;
4867
4868                         /*
4869                          * First of all, the unconditional stuff we have to do
4870                          * to disable replay of the journal when we next remount
4871                          */
4872                         sb->s_flags |= MS_RDONLY;
4873
4874                         /*
4875                          * OK, test if we are remounting a valid rw partition
4876                          * readonly, and if so set the rdonly flag and then
4877                          * mark the partition as valid again.
4878                          */
4879                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4880                             (sbi->s_mount_state & EXT4_VALID_FS))
4881                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4882
4883                         if (sbi->s_journal)
4884                                 ext4_mark_recovery_complete(sb, es);
4885                 } else {
4886                         /* Make sure we can mount this feature set readwrite */
4887                         if (!ext4_feature_set_ok(sb, 0)) {
4888                                 err = -EROFS;
4889                                 goto restore_opts;
4890                         }
4891                         /*
4892                          * Make sure the group descriptor checksums
4893                          * are sane.  If they aren't, refuse to remount r/w.
4894                          */
4895                         for (g = 0; g < sbi->s_groups_count; g++) {
4896                                 struct ext4_group_desc *gdp =
4897                                         ext4_get_group_desc(sb, g, NULL);
4898
4899                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
4900                                         ext4_msg(sb, KERN_ERR,
4901                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4902                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4903                                                le16_to_cpu(gdp->bg_checksum));
4904                                         err = -EINVAL;
4905                                         goto restore_opts;
4906                                 }
4907                         }
4908
4909                         /*
4910                          * If we have an unprocessed orphan list hanging
4911                          * around from a previously readonly bdev mount,
4912                          * require a full umount/remount for now.
4913                          */
4914                         if (es->s_last_orphan) {
4915                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4916                                        "remount RDWR because of unprocessed "
4917                                        "orphan inode list.  Please "
4918                                        "umount/remount instead");
4919                                 err = -EINVAL;
4920                                 goto restore_opts;
4921                         }
4922
4923                         /*
4924                          * Mounting a RDONLY partition read-write, so reread
4925                          * and store the current valid flag.  (It may have
4926                          * been changed by e2fsck since we originally mounted
4927                          * the partition.)
4928                          */
4929                         if (sbi->s_journal)
4930                                 ext4_clear_journal_err(sb, es);
4931                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4932                         if (!ext4_setup_super(sb, es, 0))
4933                                 sb->s_flags &= ~MS_RDONLY;
4934                         if (EXT4_HAS_INCOMPAT_FEATURE(sb,
4935                                                      EXT4_FEATURE_INCOMPAT_MMP))
4936                                 if (ext4_multi_mount_protect(sb,
4937                                                 le64_to_cpu(es->s_mmp_block))) {
4938                                         err = -EROFS;
4939                                         goto restore_opts;
4940                                 }
4941                         enable_quota = 1;
4942                 }
4943         }
4944
4945         /*
4946          * Reinitialize lazy itable initialization thread based on
4947          * current settings
4948          */
4949         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4950                 ext4_unregister_li_request(sb);
4951         else {
4952                 ext4_group_t first_not_zeroed;
4953                 first_not_zeroed = ext4_has_uninit_itable(sb);
4954                 ext4_register_li_request(sb, first_not_zeroed);
4955         }
4956
4957         ext4_setup_system_zone(sb);
4958         if (sbi->s_journal == NULL && !(old_sb_flags & MS_RDONLY))
4959                 ext4_commit_super(sb, 1);
4960
4961 #ifdef CONFIG_QUOTA
4962         /* Release old quota file names */
4963         for (i = 0; i < MAXQUOTAS; i++)
4964                 kfree(old_opts.s_qf_names[i]);
4965         if (enable_quota) {
4966                 if (sb_any_quota_suspended(sb))
4967                         dquot_resume(sb, -1);
4968                 else if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
4969                                         EXT4_FEATURE_RO_COMPAT_QUOTA)) {
4970                         err = ext4_enable_quotas(sb);
4971                         if (err)
4972                                 goto restore_opts;
4973                 }
4974         }
4975 #endif
4976
4977         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4978         kfree(orig_data);
4979         return 0;
4980
4981 restore_opts:
4982         sb->s_flags = old_sb_flags;
4983         sbi->s_mount_opt = old_opts.s_mount_opt;
4984         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4985         sbi->s_resuid = old_opts.s_resuid;
4986         sbi->s_resgid = old_opts.s_resgid;
4987         sbi->s_commit_interval = old_opts.s_commit_interval;
4988         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4989         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4990 #ifdef CONFIG_QUOTA
4991         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4992         for (i = 0; i < MAXQUOTAS; i++) {
4993                 kfree(sbi->s_qf_names[i]);
4994                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4995         }
4996 #endif
4997         kfree(orig_data);
4998         return err;
4999 }
5000
5001 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5002 {
5003         struct super_block *sb = dentry->d_sb;
5004         struct ext4_sb_info *sbi = EXT4_SB(sb);
5005         struct ext4_super_block *es = sbi->s_es;
5006         ext4_fsblk_t overhead = 0, resv_blocks;
5007         u64 fsid;
5008         s64 bfree;
5009         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5010
5011         if (!test_opt(sb, MINIX_DF))
5012                 overhead = sbi->s_overhead;
5013
5014         buf->f_type = EXT4_SUPER_MAGIC;
5015         buf->f_bsize = sb->s_blocksize;
5016         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5017         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5018                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5019         /* prevent underflow in case that few free space is available */
5020         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5021         buf->f_bavail = buf->f_bfree -
5022                         (ext4_r_blocks_count(es) + resv_blocks);
5023         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5024                 buf->f_bavail = 0;
5025         buf->f_files = le32_to_cpu(es->s_inodes_count);
5026         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5027         buf->f_namelen = EXT4_NAME_LEN;
5028         fsid = le64_to_cpup((void *)es->s_uuid) ^
5029                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5030         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5031         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5032
5033         return 0;
5034 }
5035
5036 /* Helper function for writing quotas on sync - we need to start transaction
5037  * before quota file is locked for write. Otherwise the are possible deadlocks:
5038  * Process 1                         Process 2
5039  * ext4_create()                     quota_sync()
5040  *   jbd2_journal_start()                  write_dquot()
5041  *   dquot_initialize()                         down(dqio_mutex)
5042  *     down(dqio_mutex)                    jbd2_journal_start()
5043  *
5044  */
5045
5046 #ifdef CONFIG_QUOTA
5047
5048 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5049 {
5050         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5051 }
5052
5053 static int ext4_write_dquot(struct dquot *dquot)
5054 {
5055         int ret, err;
5056         handle_t *handle;
5057         struct inode *inode;
5058
5059         inode = dquot_to_inode(dquot);
5060         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5061                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5062         if (IS_ERR(handle))
5063                 return PTR_ERR(handle);
5064         ret = dquot_commit(dquot);
5065         err = ext4_journal_stop(handle);
5066         if (!ret)
5067                 ret = err;
5068         return ret;
5069 }
5070
5071 static int ext4_acquire_dquot(struct dquot *dquot)
5072 {
5073         int ret, err;
5074         handle_t *handle;
5075
5076         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5077                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5078         if (IS_ERR(handle))
5079                 return PTR_ERR(handle);
5080         ret = dquot_acquire(dquot);
5081         err = ext4_journal_stop(handle);
5082         if (!ret)
5083                 ret = err;
5084         return ret;
5085 }
5086
5087 static int ext4_release_dquot(struct dquot *dquot)
5088 {
5089         int ret, err;
5090         handle_t *handle;
5091
5092         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5093                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5094         if (IS_ERR(handle)) {
5095                 /* Release dquot anyway to avoid endless cycle in dqput() */
5096                 dquot_release(dquot);
5097                 return PTR_ERR(handle);
5098         }
5099         ret = dquot_release(dquot);
5100         err = ext4_journal_stop(handle);
5101         if (!ret)
5102                 ret = err;
5103         return ret;
5104 }
5105
5106 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5107 {
5108         struct super_block *sb = dquot->dq_sb;
5109         struct ext4_sb_info *sbi = EXT4_SB(sb);
5110
5111         /* Are we journaling quotas? */
5112         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) ||
5113             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5114                 dquot_mark_dquot_dirty(dquot);
5115                 return ext4_write_dquot(dquot);
5116         } else {
5117                 return dquot_mark_dquot_dirty(dquot);
5118         }
5119 }
5120
5121 static int ext4_write_info(struct super_block *sb, int type)
5122 {
5123         int ret, err;
5124         handle_t *handle;
5125
5126         /* Data block + inode block */
5127         handle = ext4_journal_start(sb->s_root->d_inode, EXT4_HT_QUOTA, 2);
5128         if (IS_ERR(handle))
5129                 return PTR_ERR(handle);
5130         ret = dquot_commit_info(sb, type);
5131         err = ext4_journal_stop(handle);
5132         if (!ret)
5133                 ret = err;
5134         return ret;
5135 }
5136
5137 /*
5138  * Turn on quotas during mount time - we need to find
5139  * the quota file and such...
5140  */
5141 static int ext4_quota_on_mount(struct super_block *sb, int type)
5142 {
5143         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
5144                                         EXT4_SB(sb)->s_jquota_fmt, type);
5145 }
5146
5147 /*
5148  * Standard function to be called on quota_on
5149  */
5150 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5151                          struct path *path)
5152 {
5153         int err;
5154
5155         if (!test_opt(sb, QUOTA))
5156                 return -EINVAL;
5157
5158         /* Quotafile not on the same filesystem? */
5159         if (path->dentry->d_sb != sb)
5160                 return -EXDEV;
5161         /* Journaling quota? */
5162         if (EXT4_SB(sb)->s_qf_names[type]) {
5163                 /* Quotafile not in fs root? */
5164                 if (path->dentry->d_parent != sb->s_root)
5165                         ext4_msg(sb, KERN_WARNING,
5166                                 "Quota file not on filesystem root. "
5167                                 "Journaled quota will not work");
5168         }
5169
5170         /*
5171          * When we journal data on quota file, we have to flush journal to see
5172          * all updates to the file when we bypass pagecache...
5173          */
5174         if (EXT4_SB(sb)->s_journal &&
5175             ext4_should_journal_data(path->dentry->d_inode)) {
5176                 /*
5177                  * We don't need to lock updates but journal_flush() could
5178                  * otherwise be livelocked...
5179                  */
5180                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5181                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5182                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5183                 if (err)
5184                         return err;
5185         }
5186
5187         return dquot_quota_on(sb, type, format_id, path);
5188 }
5189
5190 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5191                              unsigned int flags)
5192 {
5193         int err;
5194         struct inode *qf_inode;
5195         unsigned long qf_inums[MAXQUOTAS] = {
5196                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5197                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
5198         };
5199
5200         BUG_ON(!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA));
5201
5202         if (!qf_inums[type])
5203                 return -EPERM;
5204
5205         qf_inode = ext4_iget(sb, qf_inums[type]);
5206         if (IS_ERR(qf_inode)) {
5207                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5208                 return PTR_ERR(qf_inode);
5209         }
5210
5211         /* Don't account quota for quota files to avoid recursion */
5212         qf_inode->i_flags |= S_NOQUOTA;
5213         err = dquot_enable(qf_inode, type, format_id, flags);
5214         iput(qf_inode);
5215
5216         return err;
5217 }
5218
5219 /* Enable usage tracking for all quota types. */
5220 static int ext4_enable_quotas(struct super_block *sb)
5221 {
5222         int type, err = 0;
5223         unsigned long qf_inums[MAXQUOTAS] = {
5224                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5225                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
5226         };
5227
5228         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
5229         for (type = 0; type < MAXQUOTAS; type++) {
5230                 if (qf_inums[type]) {
5231                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5232                                                 DQUOT_USAGE_ENABLED);
5233                         if (err) {
5234                                 ext4_warning(sb,
5235                                         "Failed to enable quota tracking "
5236                                         "(type=%d, err=%d). Please run "
5237                                         "e2fsck to fix.", type, err);
5238                                 return err;
5239                         }
5240                 }
5241         }
5242         return 0;
5243 }
5244
5245 /*
5246  * quota_on function that is used when QUOTA feature is set.
5247  */
5248 static int ext4_quota_on_sysfile(struct super_block *sb, int type,
5249                                  int format_id)
5250 {
5251         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
5252                 return -EINVAL;
5253
5254         /*
5255          * USAGE was enabled at mount time. Only need to enable LIMITS now.
5256          */
5257         return ext4_quota_enable(sb, type, format_id, DQUOT_LIMITS_ENABLED);
5258 }
5259
5260 static int ext4_quota_off(struct super_block *sb, int type)
5261 {
5262         struct inode *inode = sb_dqopt(sb)->files[type];
5263         handle_t *handle;
5264
5265         /* Force all delayed allocation blocks to be allocated.
5266          * Caller already holds s_umount sem */
5267         if (test_opt(sb, DELALLOC))
5268                 sync_filesystem(sb);
5269
5270         if (!inode)
5271                 goto out;
5272
5273         /* Update modification times of quota files when userspace can
5274          * start looking at them */
5275         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5276         if (IS_ERR(handle))
5277                 goto out;
5278         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
5279         ext4_mark_inode_dirty(handle, inode);
5280         ext4_journal_stop(handle);
5281
5282 out:
5283         return dquot_quota_off(sb, type);
5284 }
5285
5286 /*
5287  * quota_off function that is used when QUOTA feature is set.
5288  */
5289 static int ext4_quota_off_sysfile(struct super_block *sb, int type)
5290 {
5291         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
5292                 return -EINVAL;
5293
5294         /* Disable only the limits. */
5295         return dquot_disable(sb, type, DQUOT_LIMITS_ENABLED);
5296 }
5297
5298 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5299  * acquiring the locks... As quota files are never truncated and quota code
5300  * itself serializes the operations (and no one else should touch the files)
5301  * we don't have to be afraid of races */
5302 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5303                                size_t len, loff_t off)
5304 {
5305         struct inode *inode = sb_dqopt(sb)->files[type];
5306         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5307         int err = 0;
5308         int offset = off & (sb->s_blocksize - 1);
5309         int tocopy;
5310         size_t toread;
5311         struct buffer_head *bh;
5312         loff_t i_size = i_size_read(inode);
5313
5314         if (off > i_size)
5315                 return 0;
5316         if (off+len > i_size)
5317                 len = i_size-off;
5318         toread = len;
5319         while (toread > 0) {
5320                 tocopy = sb->s_blocksize - offset < toread ?
5321                                 sb->s_blocksize - offset : toread;
5322                 bh = ext4_bread(NULL, inode, blk, 0, &err);
5323                 if (err)
5324                         return err;
5325                 if (!bh)        /* A hole? */
5326                         memset(data, 0, tocopy);
5327                 else
5328                         memcpy(data, bh->b_data+offset, tocopy);
5329                 brelse(bh);
5330                 offset = 0;
5331                 toread -= tocopy;
5332                 data += tocopy;
5333                 blk++;
5334         }
5335         return len;
5336 }
5337
5338 /* Write to quotafile (we know the transaction is already started and has
5339  * enough credits) */
5340 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5341                                 const char *data, size_t len, loff_t off)
5342 {
5343         struct inode *inode = sb_dqopt(sb)->files[type];
5344         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5345         int err = 0;
5346         int offset = off & (sb->s_blocksize - 1);
5347         struct buffer_head *bh;
5348         handle_t *handle = journal_current_handle();
5349
5350         if (EXT4_SB(sb)->s_journal && !handle) {
5351                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5352                         " cancelled because transaction is not started",
5353                         (unsigned long long)off, (unsigned long long)len);
5354                 return -EIO;
5355         }
5356         /*
5357          * Since we account only one data block in transaction credits,
5358          * then it is impossible to cross a block boundary.
5359          */
5360         if (sb->s_blocksize - offset < len) {
5361                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5362                         " cancelled because not block aligned",
5363                         (unsigned long long)off, (unsigned long long)len);
5364                 return -EIO;
5365         }
5366
5367         bh = ext4_bread(handle, inode, blk, 1, &err);
5368         if (!bh)
5369                 goto out;
5370         err = ext4_journal_get_write_access(handle, bh);
5371         if (err) {
5372                 brelse(bh);
5373                 goto out;
5374         }
5375         lock_buffer(bh);
5376         memcpy(bh->b_data+offset, data, len);
5377         flush_dcache_page(bh->b_page);
5378         unlock_buffer(bh);
5379         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5380         brelse(bh);
5381 out:
5382         if (err)
5383                 return err;
5384         if (inode->i_size < off + len) {
5385                 i_size_write(inode, off + len);
5386                 EXT4_I(inode)->i_disksize = inode->i_size;
5387                 ext4_mark_inode_dirty(handle, inode);
5388         }
5389         return len;
5390 }
5391
5392 #endif
5393
5394 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5395                        const char *dev_name, void *data)
5396 {
5397         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5398 }
5399
5400 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5401 static inline void register_as_ext2(void)
5402 {
5403         int err = register_filesystem(&ext2_fs_type);
5404         if (err)
5405                 printk(KERN_WARNING
5406                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5407 }
5408
5409 static inline void unregister_as_ext2(void)
5410 {
5411         unregister_filesystem(&ext2_fs_type);
5412 }
5413
5414 static inline int ext2_feature_set_ok(struct super_block *sb)
5415 {
5416         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
5417                 return 0;
5418         if (sb->s_flags & MS_RDONLY)
5419                 return 1;
5420         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
5421                 return 0;
5422         return 1;
5423 }
5424 #else
5425 static inline void register_as_ext2(void) { }
5426 static inline void unregister_as_ext2(void) { }
5427 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5428 #endif
5429
5430 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5431 static inline void register_as_ext3(void)
5432 {
5433         int err = register_filesystem(&ext3_fs_type);
5434         if (err)
5435                 printk(KERN_WARNING
5436                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5437 }
5438
5439 static inline void unregister_as_ext3(void)
5440 {
5441         unregister_filesystem(&ext3_fs_type);
5442 }
5443
5444 static inline int ext3_feature_set_ok(struct super_block *sb)
5445 {
5446         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
5447                 return 0;
5448         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
5449                 return 0;
5450         if (sb->s_flags & MS_RDONLY)
5451                 return 1;
5452         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
5453                 return 0;
5454         return 1;
5455 }
5456 #else
5457 static inline void register_as_ext3(void) { }
5458 static inline void unregister_as_ext3(void) { }
5459 static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
5460 #endif
5461
5462 static struct file_system_type ext4_fs_type = {
5463         .owner          = THIS_MODULE,
5464         .name           = "ext4",
5465         .mount          = ext4_mount,
5466         .kill_sb        = kill_block_super,
5467         .fs_flags       = FS_REQUIRES_DEV,
5468 };
5469 MODULE_ALIAS_FS("ext4");
5470
5471 static int __init ext4_init_feat_adverts(void)
5472 {
5473         struct ext4_features *ef;
5474         int ret = -ENOMEM;
5475
5476         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
5477         if (!ef)
5478                 goto out;
5479
5480         ef->f_kobj.kset = ext4_kset;
5481         init_completion(&ef->f_kobj_unregister);
5482         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
5483                                    "features");
5484         if (ret) {
5485                 kfree(ef);
5486                 goto out;
5487         }
5488
5489         ext4_feat = ef;
5490         ret = 0;
5491 out:
5492         return ret;
5493 }
5494
5495 static void ext4_exit_feat_adverts(void)
5496 {
5497         kobject_put(&ext4_feat->f_kobj);
5498         wait_for_completion(&ext4_feat->f_kobj_unregister);
5499         kfree(ext4_feat);
5500 }
5501
5502 /* Shared across all ext4 file systems */
5503 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5504 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5505
5506 static int __init ext4_init_fs(void)
5507 {
5508         int i, err;
5509
5510         ext4_li_info = NULL;
5511         mutex_init(&ext4_li_mtx);
5512
5513         /* Build-time check for flags consistency */
5514         ext4_check_flag_values();
5515
5516         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5517                 mutex_init(&ext4__aio_mutex[i]);
5518                 init_waitqueue_head(&ext4__ioend_wq[i]);
5519         }
5520
5521         err = ext4_init_es();
5522         if (err)
5523                 return err;
5524
5525         err = ext4_init_pageio();
5526         if (err)
5527                 goto out7;
5528
5529         err = ext4_init_system_zone();
5530         if (err)
5531                 goto out6;
5532         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
5533         if (!ext4_kset) {
5534                 err = -ENOMEM;
5535                 goto out5;
5536         }
5537         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
5538
5539         err = ext4_init_feat_adverts();
5540         if (err)
5541                 goto out4;
5542
5543         err = ext4_init_mballoc();
5544         if (err)
5545                 goto out2;
5546         else
5547                 ext4_mballoc_ready = 1;
5548         err = init_inodecache();
5549         if (err)
5550                 goto out1;
5551         register_as_ext3();
5552         register_as_ext2();
5553         err = register_filesystem(&ext4_fs_type);
5554         if (err)
5555                 goto out;
5556
5557         return 0;
5558 out:
5559         unregister_as_ext2();
5560         unregister_as_ext3();
5561         destroy_inodecache();
5562 out1:
5563         ext4_mballoc_ready = 0;
5564         ext4_exit_mballoc();
5565 out2:
5566         ext4_exit_feat_adverts();
5567 out4:
5568         if (ext4_proc_root)
5569                 remove_proc_entry("fs/ext4", NULL);
5570         kset_unregister(ext4_kset);
5571 out5:
5572         ext4_exit_system_zone();
5573 out6:
5574         ext4_exit_pageio();
5575 out7:
5576         ext4_exit_es();
5577
5578         return err;
5579 }
5580
5581 static void __exit ext4_exit_fs(void)
5582 {
5583         ext4_destroy_lazyinit_thread();
5584         unregister_as_ext2();
5585         unregister_as_ext3();
5586         unregister_filesystem(&ext4_fs_type);
5587         destroy_inodecache();
5588         ext4_exit_mballoc();
5589         ext4_exit_feat_adverts();
5590         remove_proc_entry("fs/ext4", NULL);
5591         kset_unregister(ext4_kset);
5592         ext4_exit_system_zone();
5593         ext4_exit_pageio();
5594         ext4_exit_es();
5595 }
5596
5597 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5598 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5599 MODULE_LICENSE("GPL");
5600 module_init(ext4_init_fs)
5601 module_exit(ext4_exit_fs)