kernel/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/slab.h>
  25 #include <linux/init.h>
  26 #include <linux/blkdev.h>
  27 #include <linux/parser.h>
  28 #include <linux/buffer_head.h>
  29 #include <linux/exportfs.h>
  30 #include <linux/vfs.h>
  31 #include <linux/random.h>
  32 #include <linux/mount.h>
  33 #include <linux/namei.h>
  34 #include <linux/quotaops.h>
  35 #include <linux/seq_file.h>
  36 #include <linux/proc_fs.h>
  37 #include <linux/ctype.h>
  38 #include <linux/log2.h>
  39 #include <linux/crc16.h>
  40 #include <linux/cleancache.h>
  41 #include <asm/uaccess.h>
  42
  43 #include <linux/kthread.h>
  44 #include <linux/freezer.h>
  45
  46 #include "ext4.h"
  47 #include "ext4_extents.h"       /* Needed for trace points definition */
  48 #include "ext4_jbd2.h"
  49 #include "xattr.h"
  50 #include "acl.h"
  51 #include "mballoc.h"
  52
  53 #define CREATE_TRACE_POINTS
  54 #include <trace/events/ext4.h>
  55
  56 static struct proc_dir_entry *ext4_proc_root;
  57 static struct kset *ext4_kset;
  58 static struct ext4_lazy_init *ext4_li_info;
  59 static struct mutex ext4_li_mtx;
  60 static struct ext4_features *ext4_feat;
  61 static int ext4_mballoc_ready;
  62
  63 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  64                              unsigned long journal_devnum);
  65 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  66 static int ext4_commit_super(struct super_block *sb, int sync);
  67 static void ext4_mark_recovery_complete(struct super_block *sb,
  68                                         struct ext4_super_block *es);
  69 static void ext4_clear_journal_err(struct super_block *sb,
  70                                    struct ext4_super_block *es);
  71 static int ext4_sync_fs(struct super_block *sb, int wait);
  72 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  73 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  74 static int ext4_unfreeze(struct super_block *sb);
  75 static int ext4_freeze(struct super_block *sb);
  76 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  77                        const char *dev_name, void *data);
  78 static inline int ext2_feature_set_ok(struct super_block *sb);
  79 static inline int ext3_feature_set_ok(struct super_block *sb);
  80 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  81 static void ext4_destroy_lazyinit_thread(void);
  82 static void ext4_unregister_li_request(struct super_block *sb);
  83 static void ext4_clear_request_list(void);
  84 static int ext4_reserve_clusters(struct ext4_sb_info *, ext4_fsblk_t);
  85
  86 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
  87 static struct file_system_type ext2_fs_type = {
  88         .owner          = THIS_MODULE,
  89         .name           = "ext2",
  90         .mount          = ext4_mount,
  91         .kill_sb        = kill_block_super,
  92         .fs_flags       = FS_REQUIRES_DEV,
  93 };
  94 MODULE_ALIAS_FS("ext2");
  95 MODULE_ALIAS("ext2");
  96 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
  97 #else
  98 #define IS_EXT2_SB(sb) (0)
  99 #endif
 100
 101
 102 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
 103 static struct file_system_type ext3_fs_type = {
 104         .owner          = THIS_MODULE,
 105         .name           = "ext3",
 106         .mount          = ext4_mount,
 107         .kill_sb        = kill_block_super,
 108         .fs_flags       = FS_REQUIRES_DEV,
 109 };
 110 MODULE_ALIAS_FS("ext3");
 111 MODULE_ALIAS("ext3");
 112 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 113 #else
 114 #define IS_EXT3_SB(sb) (0)
 115 #endif
 116
 117 static int ext4_verify_csum_type(struct super_block *sb,
 118                                  struct ext4_super_block *es)
 119 {
 120         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 121                                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 122                 return 1;
 123
 124         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 125 }
 126
 127 static __le32 ext4_superblock_csum(struct super_block *sb,
 128                                    struct ext4_super_block *es)
 129 {
 130         struct ext4_sb_info *sbi = EXT4_SB(sb);
 131         int offset = offsetof(struct ext4_super_block, s_checksum);
 132         __u32 csum;
 133
 134         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 135
 136         return cpu_to_le32(csum);
 137 }
 138
 139 static int ext4_superblock_csum_verify(struct super_block *sb,
 140                                        struct ext4_super_block *es)
 141 {
 142         if (!ext4_has_metadata_csum(sb))
 143                 return 1;
 144
 145         return es->s_checksum == ext4_superblock_csum(sb, es);
 146 }
 147
 148 void ext4_superblock_csum_set(struct super_block *sb)
 149 {
 150         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 151
 152         if (!ext4_has_metadata_csum(sb))
 153                 return;
 154
 155         es->s_checksum = ext4_superblock_csum(sb, es);
 156 }
 157
 158 void *ext4_kvmalloc(size_t size, gfp_t flags)
 159 {
 160         void *ret;
 161
 162         ret = kmalloc(size, flags | __GFP_NOWARN);
 163         if (!ret)
 164                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 165         return ret;
 166 }
 167
 168 void *ext4_kvzalloc(size_t size, gfp_t flags)
 169 {
 170         void *ret;
 171
 172         ret = kzalloc(size, flags | __GFP_NOWARN);
 173         if (!ret)
 174                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 175         return ret;
 176 }
 177
 178 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 179                                struct ext4_group_desc *bg)
 180 {
 181         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 182                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 183                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 184 }
 185
 186 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 187                                struct ext4_group_desc *bg)
 188 {
 189         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 190                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 191                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 192 }
 193
 194 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 195                               struct ext4_group_desc *bg)
 196 {
 197         return le32_to_cpu(bg->bg_inode_table_lo) |
 198                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 199                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 200 }
 201
 202 __u32 ext4_free_group_clusters(struct super_block *sb,
 203                                struct ext4_group_desc *bg)
 204 {
 205         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 206                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 207                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 208 }
 209
 210 __u32 ext4_free_inodes_count(struct super_block *sb,
 211                               struct ext4_group_desc *bg)
 212 {
 213         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 214                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 215                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 216 }
 217
 218 __u32 ext4_used_dirs_count(struct super_block *sb,
 219                               struct ext4_group_desc *bg)
 220 {
 221         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 222                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 223                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 224 }
 225
 226 __u32 ext4_itable_unused_count(struct super_block *sb,
 227                               struct ext4_group_desc *bg)
 228 {
 229         return le16_to_cpu(bg->bg_itable_unused_lo) |
 230                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 231                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 232 }
 233
 234 void ext4_block_bitmap_set(struct super_block *sb,
 235                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 236 {
 237         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 238         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 239                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 240 }
 241
 242 void ext4_inode_bitmap_set(struct super_block *sb,
 243                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 244 {
 245         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 246         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 247                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 248 }
 249
 250 void ext4_inode_table_set(struct super_block *sb,
 251                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 252 {
 253         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 254         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 255                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 256 }
 257
 258 void ext4_free_group_clusters_set(struct super_block *sb,
 259                                   struct ext4_group_desc *bg, __u32 count)
 260 {
 261         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 262         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 263                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 264 }
 265
 266 void ext4_free_inodes_set(struct super_block *sb,
 267                           struct ext4_group_desc *bg, __u32 count)
 268 {
 269         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 270         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 271                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 272 }
 273
 274 void ext4_used_dirs_set(struct super_block *sb,
 275                           struct ext4_group_desc *bg, __u32 count)
 276 {
 277         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 278         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 279                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 280 }
 281
 282 void ext4_itable_unused_set(struct super_block *sb,
 283                           struct ext4_group_desc *bg, __u32 count)
 284 {
 285         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 286         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 287                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 288 }
 289
 290
 291 static void __save_error_info(struct super_block *sb, const char *func,
 292                             unsigned int line)
 293 {
 294         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 295
 296         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 297         if (bdev_read_only(sb->s_bdev))
 298                 return;
 299         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 300         es->s_last_error_time = cpu_to_le32(get_seconds());
 301         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 302         es->s_last_error_line = cpu_to_le32(line);
 303         if (!es->s_first_error_time) {
 304                 es->s_first_error_time = es->s_last_error_time;
 305                 strncpy(es->s_first_error_func, func,
 306                         sizeof(es->s_first_error_func));
 307                 es->s_first_error_line = cpu_to_le32(line);
 308                 es->s_first_error_ino = es->s_last_error_ino;
 309                 es->s_first_error_block = es->s_last_error_block;
 310         }
 311         /*
 312          * Start the daily error reporting function if it hasn't been
 313          * started already
 314          */
 315         if (!es->s_error_count)
 316                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 317         le32_add_cpu(&es->s_error_count, 1);
 318 }
 319
 320 static void save_error_info(struct super_block *sb, const char *func,
 321                             unsigned int line)
 322 {
 323         __save_error_info(sb, func, line);
 324         ext4_commit_super(sb, 1);
 325 }
 326
 327 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 328 {
 329         struct super_block              *sb = journal->j_private;
 330         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 331         int                             error = is_journal_aborted(journal);
 332         struct ext4_journal_cb_entry    *jce;
 333
 334         BUG_ON(txn->t_state == T_FINISHED);
 335         spin_lock(&sbi->s_md_lock);
 336         while (!list_empty(&txn->t_private_list)) {
 337                 jce = list_entry(txn->t_private_list.next,
 338                                  struct ext4_journal_cb_entry, jce_list);
 339                 list_del_init(&jce->jce_list);
 340                 spin_unlock(&sbi->s_md_lock);
 341                 jce->jce_func(sb, jce, error);
 342                 spin_lock(&sbi->s_md_lock);
 343         }
 344         spin_unlock(&sbi->s_md_lock);
 345 }
 346
 347 /* Deal with the reporting of failure conditions on a filesystem such as
 348  * inconsistencies detected or read IO failures.
 349  *
 350  * On ext2, we can store the error state of the filesystem in the
 351  * superblock.  That is not possible on ext4, because we may have other
 352  * write ordering constraints on the superblock which prevent us from
 353  * writing it out straight away; and given that the journal is about to
 354  * be aborted, we can't rely on the current, or future, transactions to
 355  * write out the superblock safely.
 356  *
 357  * We'll just use the jbd2_journal_abort() error code to record an error in
 358  * the journal instead.  On recovery, the journal will complain about
 359  * that error until we've noted it down and cleared it.
 360  */
 361
 362 static void ext4_handle_error(struct super_block *sb)
 363 {
 364         if (sb->s_flags & MS_RDONLY)
 365                 return;
 366
 367         if (!test_opt(sb, ERRORS_CONT)) {
 368                 journal_t *journal = EXT4_SB(sb)->s_journal;
 369
 370                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 371                 if (journal)
 372                         jbd2_journal_abort(journal, -EIO);
 373         }
 374         if (test_opt(sb, ERRORS_RO)) {
 375                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 376                 /*
 377                  * Make sure updated value of ->s_mount_flags will be visible
 378                  * before ->s_flags update
 379                  */
 380                 smp_wmb();
 381                 sb->s_flags |= MS_RDONLY;
 382         }
 383         if (test_opt(sb, ERRORS_PANIC))
 384                 panic("EXT4-fs (device %s): panic forced after error\n",
 385                         sb->s_id);
 386 }
 387
 388 #define ext4_error_ratelimit(sb)                                        \
 389                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 390                              "EXT4-fs error")
 391
 392 void __ext4_error(struct super_block *sb, const char *function,
 393                   unsigned int line, const char *fmt, ...)
 394 {
 395         struct va_format vaf;
 396         va_list args;
 397
 398         if (ext4_error_ratelimit(sb)) {
 399                 va_start(args, fmt);
 400                 vaf.fmt = fmt;
 401                 vaf.va = &args;
 402                 printk(KERN_CRIT
 403                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 404                        sb->s_id, function, line, current->comm, &vaf);
 405                 va_end(args);
 406         }
 407         save_error_info(sb, function, line);
 408         ext4_handle_error(sb);
 409 }
 410
 411 void __ext4_error_inode(struct inode *inode, const char *function,
 412                         unsigned int line, ext4_fsblk_t block,
 413                         const char *fmt, ...)
 414 {
 415         va_list args;
 416         struct va_format vaf;
 417         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 418
 419         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 420         es->s_last_error_block = cpu_to_le64(block);
 421         if (ext4_error_ratelimit(inode->i_sb)) {
 422                 va_start(args, fmt);
 423                 vaf.fmt = fmt;
 424                 vaf.va = &args;
 425                 if (block)
 426                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 427                                "inode #%lu: block %llu: comm %s: %pV\n",
 428                                inode->i_sb->s_id, function, line, inode->i_ino,
 429                                block, current->comm, &vaf);
 430                 else
 431                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 432                                "inode #%lu: comm %s: %pV\n",
 433                                inode->i_sb->s_id, function, line, inode->i_ino,
 434                                current->comm, &vaf);
 435                 va_end(args);
 436         }
 437         save_error_info(inode->i_sb, function, line);
 438         ext4_handle_error(inode->i_sb);
 439 }
 440
 441 void __ext4_error_file(struct file *file, const char *function,
 442                        unsigned int line, ext4_fsblk_t block,
 443                        const char *fmt, ...)
 444 {
 445         va_list args;
 446         struct va_format vaf;
 447         struct ext4_super_block *es;
 448         struct inode *inode = file_inode(file);
 449         char pathname[80], *path;
 450
 451         es = EXT4_SB(inode->i_sb)->s_es;
 452         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 453         if (ext4_error_ratelimit(inode->i_sb)) {
 454                 path = d_path(&(file->f_path), pathname, sizeof(pathname));
 455                 if (IS_ERR(path))
 456                         path = "(unknown)";
 457                 va_start(args, fmt);
 458                 vaf.fmt = fmt;
 459                 vaf.va = &args;
 460                 if (block)
 461                         printk(KERN_CRIT
 462                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 463                                "block %llu: comm %s: path %s: %pV\n",
 464                                inode->i_sb->s_id, function, line, inode->i_ino,
 465                                block, current->comm, path, &vaf);
 466                 else
 467                         printk(KERN_CRIT
 468                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 469                                "comm %s: path %s: %pV\n",
 470                                inode->i_sb->s_id, function, line, inode->i_ino,
 471                                current->comm, path, &vaf);
 472                 va_end(args);
 473         }
 474         save_error_info(inode->i_sb, function, line);
 475         ext4_handle_error(inode->i_sb);
 476 }
 477
 478 const char *ext4_decode_error(struct super_block *sb, int errno,
 479                               char nbuf[16])
 480 {
 481         char *errstr = NULL;
 482
 483         switch (errno) {
 484         case -EIO:
 485                 errstr = "IO failure";
 486                 break;
 487         case -ENOMEM:
 488                 errstr = "Out of memory";
 489                 break;
 490         case -EROFS:
 491                 if (!sb || (EXT4_SB(sb)->s_journal &&
 492                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 493                         errstr = "Journal has aborted";
 494                 else
 495                         errstr = "Readonly filesystem";
 496                 break;
 497         default:
 498                 /* If the caller passed in an extra buffer for unknown
 499                  * errors, textualise them now.  Else we just return
 500                  * NULL. */
 501                 if (nbuf) {
 502                         /* Check for truncated error codes... */
 503                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 504                                 errstr = nbuf;
 505                 }
 506                 break;
 507         }
 508
 509         return errstr;
 510 }
 511
 512 /* __ext4_std_error decodes expected errors from journaling functions
 513  * automatically and invokes the appropriate error response.  */
 514
 515 void __ext4_std_error(struct super_block *sb, const char *function,
 516                       unsigned int line, int errno)
 517 {
 518         char nbuf[16];
 519         const char *errstr;
 520
 521         /* Special case: if the error is EROFS, and we're not already
 522          * inside a transaction, then there's really no point in logging
 523          * an error. */
 524         if (errno == -EROFS && journal_current_handle() == NULL &&
 525             (sb->s_flags & MS_RDONLY))
 526                 return;
 527
 528         if (ext4_error_ratelimit(sb)) {
 529                 errstr = ext4_decode_error(sb, errno, nbuf);
 530                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 531                        sb->s_id, function, line, errstr);
 532         }
 533
 534         save_error_info(sb, function, line);
 535         ext4_handle_error(sb);
 536 }
 537
 538 /*
 539  * ext4_abort is a much stronger failure handler than ext4_error.  The
 540  * abort function may be used to deal with unrecoverable failures such
 541  * as journal IO errors or ENOMEM at a critical moment in log management.
 542  *
 543  * We unconditionally force the filesystem into an ABORT|READONLY state,
 544  * unless the error response on the fs has been set to panic in which
 545  * case we take the easy way out and panic immediately.
 546  */
 547
 548 void __ext4_abort(struct super_block *sb, const char *function,
 549                 unsigned int line, const char *fmt, ...)
 550 {
 551         va_list args;
 552
 553         save_error_info(sb, function, line);
 554         va_start(args, fmt);
 555         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 556                function, line);
 557         vprintk(fmt, args);
 558         printk("\n");
 559         va_end(args);
 560
 561         if ((sb->s_flags & MS_RDONLY) == 0) {
 562                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 563                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 564                 /*
 565                  * Make sure updated value of ->s_mount_flags will be visible
 566                  * before ->s_flags update
 567                  */
 568                 smp_wmb();
 569                 sb->s_flags |= MS_RDONLY;
 570                 if (EXT4_SB(sb)->s_journal)
 571                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 572                 save_error_info(sb, function, line);
 573         }
 574         if (test_opt(sb, ERRORS_PANIC))
 575                 panic("EXT4-fs panic from previous error\n");
 576 }
 577
 578 void __ext4_msg(struct super_block *sb,
 579                 const char *prefix, const char *fmt, ...)
 580 {
 581         struct va_format vaf;
 582         va_list args;
 583
 584         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 585                 return;
 586
 587         va_start(args, fmt);
 588         vaf.fmt = fmt;
 589         vaf.va = &args;
 590         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 591         va_end(args);
 592 }
 593
 594 void __ext4_warning(struct super_block *sb, const char *function,
 595                     unsigned int line, const char *fmt, ...)
 596 {
 597         struct va_format vaf;
 598         va_list args;
 599
 600         if (!___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 601                           "EXT4-fs warning"))
 602                 return;
 603
 604         va_start(args, fmt);
 605         vaf.fmt = fmt;
 606         vaf.va = &args;
 607         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 608                sb->s_id, function, line, &vaf);
 609         va_end(args);
 610 }
 611
 612 void __ext4_grp_locked_error(const char *function, unsigned int line,
 613                              struct super_block *sb, ext4_group_t grp,
 614                              unsigned long ino, ext4_fsblk_t block,
 615                              const char *fmt, ...)
 616 __releases(bitlock)
 617 __acquires(bitlock)
 618 {
 619         struct va_format vaf;
 620         va_list args;
 621         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 622
 623         es->s_last_error_ino = cpu_to_le32(ino);
 624         es->s_last_error_block = cpu_to_le64(block);
 625         __save_error_info(sb, function, line);
 626
 627         if (ext4_error_ratelimit(sb)) {
 628                 va_start(args, fmt);
 629                 vaf.fmt = fmt;
 630                 vaf.va = &args;
 631                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 632                        sb->s_id, function, line, grp);
 633                 if (ino)
 634                         printk(KERN_CONT "inode %lu: ", ino);
 635                 if (block)
 636                         printk(KERN_CONT "block %llu:",
 637                                (unsigned long long) block);
 638                 printk(KERN_CONT "%pV\n", &vaf);
 639                 va_end(args);
 640         }
 641
 642         if (test_opt(sb, ERRORS_CONT)) {
 643                 ext4_commit_super(sb, 0);
 644                 return;
 645         }
 646
 647         ext4_unlock_group(sb, grp);
 648         ext4_handle_error(sb);
 649         /*
 650          * We only get here in the ERRORS_RO case; relocking the group
 651          * may be dangerous, but nothing bad will happen since the
 652          * filesystem will have already been marked read/only and the
 653          * journal has been aborted.  We return 1 as a hint to callers
 654          * who might what to use the return value from
 655          * ext4_grp_locked_error() to distinguish between the
 656          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 657          * aggressively from the ext4 function in question, with a
 658          * more appropriate error code.
 659          */
 660         ext4_lock_group(sb, grp);
 661         return;
 662 }
 663
 664 void ext4_update_dynamic_rev(struct super_block *sb)
 665 {
 666         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 667
 668         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 669                 return;
 670
 671         ext4_warning(sb,
 672                      "updating to rev %d because of new feature flag, "
 673                      "running e2fsck is recommended",
 674                      EXT4_DYNAMIC_REV);
 675
 676         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 677         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 678         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 679         /* leave es->s_feature_*compat flags alone */
 680         /* es->s_uuid will be set by e2fsck if empty */
 681
 682         /*
 683          * The rest of the superblock fields should be zero, and if not it
 684          * means they are likely already in use, so leave them alone.  We
 685          * can leave it up to e2fsck to clean up any inconsistencies there.
 686          */
 687 }
 688
 689 /*
 690  * Open the external journal device
 691  */
 692 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 693 {
 694         struct block_device *bdev;
 695         char b[BDEVNAME_SIZE];
 696
 697         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 698         if (IS_ERR(bdev))
 699                 goto fail;
 700         return bdev;
 701
 702 fail:
 703         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 704                         __bdevname(dev, b), PTR_ERR(bdev));
 705         return NULL;
 706 }
 707
 708 /*
 709  * Release the journal device
 710  */
 711 static void ext4_blkdev_put(struct block_device *bdev)
 712 {
 713         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 714 }
 715
 716 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 717 {
 718         struct block_device *bdev;
 719         bdev = sbi->journal_bdev;
 720         if (bdev) {
 721                 ext4_blkdev_put(bdev);
 722                 sbi->journal_bdev = NULL;
 723         }
 724 }
 725
 726 static inline struct inode *orphan_list_entry(struct list_head *l)
 727 {
 728         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 729 }
 730
 731 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 732 {
 733         struct list_head *l;
 734
 735         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 736                  le32_to_cpu(sbi->s_es->s_last_orphan));
 737
 738         printk(KERN_ERR "sb_info orphan list:\n");
 739         list_for_each(l, &sbi->s_orphan) {
 740                 struct inode *inode = orphan_list_entry(l);
 741                 printk(KERN_ERR "  "
 742                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 743                        inode->i_sb->s_id, inode->i_ino, inode,
 744                        inode->i_mode, inode->i_nlink,
 745                        NEXT_ORPHAN(inode));
 746         }
 747 }
 748
 749 static void ext4_put_super(struct super_block *sb)
 750 {
 751         struct ext4_sb_info *sbi = EXT4_SB(sb);
 752         struct ext4_super_block *es = sbi->s_es;
 753         int i, err;
 754
 755         ext4_unregister_li_request(sb);
 756         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 757
 758         flush_workqueue(sbi->rsv_conversion_wq);
 759         destroy_workqueue(sbi->rsv_conversion_wq);
 760
 761         if (sbi->s_journal) {
 762                 err = jbd2_journal_destroy(sbi->s_journal);
 763                 sbi->s_journal = NULL;
 764                 if (err < 0)
 765                         ext4_abort(sb, "Couldn't clean up the journal");
 766         }
 767
 768         ext4_es_unregister_shrinker(sbi);
 769         del_timer_sync(&sbi->s_err_report);
 770         ext4_release_system_zone(sb);
 771         ext4_mb_release(sb);
 772         ext4_ext_release(sb);
 773         ext4_xattr_put_super(sb);
 774
 775         if (!(sb->s_flags & MS_RDONLY)) {
 776                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 777                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 778         }
 779         if (!(sb->s_flags & MS_RDONLY))
 780                 ext4_commit_super(sb, 1);
 781
 782         if (sbi->s_proc) {
 783                 remove_proc_entry("options", sbi->s_proc);
 784                 remove_proc_entry(sb->s_id, ext4_proc_root);
 785         }
 786         kobject_del(&sbi->s_kobj);
 787
 788         for (i = 0; i < sbi->s_gdb_count; i++)
 789                 brelse(sbi->s_group_desc[i]);
 790         kvfree(sbi->s_group_desc);
 791         kvfree(sbi->s_flex_groups);
 792         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 793         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 794         percpu_counter_destroy(&sbi->s_dirs_counter);
 795         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 796         brelse(sbi->s_sbh);
 797 #ifdef CONFIG_QUOTA
 798         for (i = 0; i < EXT4_MAXQUOTAS; i++)
 799                 kfree(sbi->s_qf_names[i]);
 800 #endif
 801
 802         /* Debugging code just in case the in-memory inode orphan list
 803          * isn't empty.  The on-disk one can be non-empty if we've
 804          * detected an error and taken the fs readonly, but the
 805          * in-memory list had better be clean by this point. */
 806         if (!list_empty(&sbi->s_orphan))
 807                 dump_orphan_list(sb, sbi);
 808         J_ASSERT(list_empty(&sbi->s_orphan));
 809
 810         sync_blockdev(sb->s_bdev);
 811         invalidate_bdev(sb->s_bdev);
 812         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 813                 /*
 814                  * Invalidate the journal device's buffers.  We don't want them
 815                  * floating about in memory - the physical journal device may
 816                  * hotswapped, and it breaks the `ro-after' testing code.
 817                  */
 818                 sync_blockdev(sbi->journal_bdev);
 819                 invalidate_bdev(sbi->journal_bdev);
 820                 ext4_blkdev_remove(sbi);
 821         }
 822         if (sbi->s_mb_cache) {
 823                 ext4_xattr_destroy_cache(sbi->s_mb_cache);
 824                 sbi->s_mb_cache = NULL;
 825         }
 826         if (sbi->s_mmp_tsk)
 827                 kthread_stop(sbi->s_mmp_tsk);
 828         sb->s_fs_info = NULL;
 829         /*
 830          * Now that we are completely done shutting down the
 831          * superblock, we need to actually destroy the kobject.
 832          */
 833         kobject_put(&sbi->s_kobj);
 834         wait_for_completion(&sbi->s_kobj_unregister);
 835         if (sbi->s_chksum_driver)
 836                 crypto_free_shash(sbi->s_chksum_driver);
 837         kfree(sbi->s_blockgroup_lock);
 838         kfree(sbi);
 839 }
 840
 841 static struct kmem_cache *ext4_inode_cachep;
 842
 843 /*
 844  * Called inside transaction, so use GFP_NOFS
 845  */
 846 static struct inode *ext4_alloc_inode(struct super_block *sb)
 847 {
 848         struct ext4_inode_info *ei;
 849
 850         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 851         if (!ei)
 852                 return NULL;
 853
 854         ei->vfs_inode.i_version = 1;
 855         spin_lock_init(&ei->i_raw_lock);
 856         INIT_LIST_HEAD(&ei->i_prealloc_list);
 857         spin_lock_init(&ei->i_prealloc_lock);
 858         ext4_es_init_tree(&ei->i_es_tree);
 859         rwlock_init(&ei->i_es_lock);
 860         INIT_LIST_HEAD(&ei->i_es_list);
 861         ei->i_es_all_nr = 0;
 862         ei->i_es_shk_nr = 0;
 863         ei->i_es_shrink_lblk = 0;
 864         ei->i_reserved_data_blocks = 0;
 865         ei->i_reserved_meta_blocks = 0;
 866         ei->i_allocated_meta_blocks = 0;
 867         ei->i_da_metadata_calc_len = 0;
 868         ei->i_da_metadata_calc_last_lblock = 0;
 869         spin_lock_init(&(ei->i_block_reservation_lock));
 870 #ifdef CONFIG_QUOTA
 871         ei->i_reserved_quota = 0;
 872         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
 873 #endif
 874         ei->jinode = NULL;
 875         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
 876         spin_lock_init(&ei->i_completed_io_lock);
 877         ei->i_sync_tid = 0;
 878         ei->i_datasync_tid = 0;
 879         atomic_set(&ei->i_ioend_count, 0);
 880         atomic_set(&ei->i_unwritten, 0);
 881         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
 882 #ifdef CONFIG_EXT4_FS_ENCRYPTION
 883         ei->i_encryption_key.mode = EXT4_ENCRYPTION_MODE_INVALID;
 884 #endif
 885
 886         return &ei->vfs_inode;
 887 }
 888
 889 static int ext4_drop_inode(struct inode *inode)
 890 {
 891         int drop = generic_drop_inode(inode);
 892
 893         trace_ext4_drop_inode(inode, drop);
 894         return drop;
 895 }
 896
 897 static void ext4_i_callback(struct rcu_head *head)
 898 {
 899         struct inode *inode = container_of(head, struct inode, i_rcu);
 900         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 901 }
 902
 903 static void ext4_destroy_inode(struct inode *inode)
 904 {
 905         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 906                 ext4_msg(inode->i_sb, KERN_ERR,
 907                          "Inode %lu (%p): orphan list check failed!",
 908                          inode->i_ino, EXT4_I(inode));
 909                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 910                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 911                                 true);
 912                 dump_stack();
 913         }
 914         call_rcu(&inode->i_rcu, ext4_i_callback);
 915 }
 916
 917 static void init_once(void *foo)
 918 {
 919         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 920
 921         INIT_LIST_HEAD(&ei->i_orphan);
 922         init_rwsem(&ei->xattr_sem);
 923         init_rwsem(&ei->i_data_sem);
 924         inode_init_once(&ei->vfs_inode);
 925 }
 926
 927 static int __init init_inodecache(void)
 928 {
 929         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 930                                              sizeof(struct ext4_inode_info),
 931                                              0, (SLAB_RECLAIM_ACCOUNT|
 932                                                 SLAB_MEM_SPREAD),
 933                                              init_once);
 934         if (ext4_inode_cachep == NULL)
 935                 return -ENOMEM;
 936         return 0;
 937 }
 938
 939 static void destroy_inodecache(void)
 940 {
 941         /*
 942          * Make sure all delayed rcu free inodes are flushed before we
 943          * destroy cache.
 944          */
 945         rcu_barrier();
 946         kmem_cache_destroy(ext4_inode_cachep);
 947 }
 948
 949 void ext4_clear_inode(struct inode *inode)
 950 {
 951         invalidate_inode_buffers(inode);
 952         clear_inode(inode);
 953         dquot_drop(inode);
 954         ext4_discard_preallocations(inode);
 955         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
 956         if (EXT4_I(inode)->jinode) {
 957                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
 958                                                EXT4_I(inode)->jinode);
 959                 jbd2_free_inode(EXT4_I(inode)->jinode);
 960                 EXT4_I(inode)->jinode = NULL;
 961         }
 962 }
 963
 964 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 965                                         u64 ino, u32 generation)
 966 {
 967         struct inode *inode;
 968
 969         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 970                 return ERR_PTR(-ESTALE);
 971         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 972                 return ERR_PTR(-ESTALE);
 973
 974         /* iget isn't really right if the inode is currently unallocated!!
 975          *
 976          * ext4_read_inode will return a bad_inode if the inode had been
 977          * deleted, so we should be safe.
 978          *
 979          * Currently we don't know the generation for parent directory, so
 980          * a generation of 0 means "accept any"
 981          */
 982         inode = ext4_iget_normal(sb, ino);
 983         if (IS_ERR(inode))
 984                 return ERR_CAST(inode);
 985         if (generation && inode->i_generation != generation) {
 986                 iput(inode);
 987                 return ERR_PTR(-ESTALE);
 988         }
 989
 990         return inode;
 991 }
 992
 993 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
 994                                         int fh_len, int fh_type)
 995 {
 996         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 997                                     ext4_nfs_get_inode);
 998 }
 999
1000 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1001                                         int fh_len, int fh_type)
1002 {
1003         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1004                                     ext4_nfs_get_inode);
1005 }
1006
1007 /*
1008  * Try to release metadata pages (indirect blocks, directories) which are
1009  * mapped via the block device.  Since these pages could have journal heads
1010  * which would prevent try_to_free_buffers() from freeing them, we must use
1011  * jbd2 layer's try_to_free_buffers() function to release them.
1012  */
1013 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1014                                  gfp_t wait)
1015 {
1016         journal_t *journal = EXT4_SB(sb)->s_journal;
1017
1018         WARN_ON(PageChecked(page));
1019         if (!page_has_buffers(page))
1020                 return 0;
1021         if (journal)
1022                 return jbd2_journal_try_to_free_buffers(journal, page,
1023                                                         wait & ~__GFP_WAIT);
1024         return try_to_free_buffers(page);
1025 }
1026
1027 #ifdef CONFIG_QUOTA
1028 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1029 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1030
1031 static int ext4_write_dquot(struct dquot *dquot);
1032 static int ext4_acquire_dquot(struct dquot *dquot);
1033 static int ext4_release_dquot(struct dquot *dquot);
1034 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1035 static int ext4_write_info(struct super_block *sb, int type);
1036 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1037                          struct path *path);
1038 static int ext4_quota_off(struct super_block *sb, int type);
1039 static int ext4_quota_on_mount(struct super_block *sb, int type);
1040 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1041                                size_t len, loff_t off);
1042 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1043                                 const char *data, size_t len, loff_t off);
1044 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1045                              unsigned int flags);
1046 static int ext4_enable_quotas(struct super_block *sb);
1047
1048 static struct dquot **ext4_get_dquots(struct inode *inode)
1049 {
1050         return EXT4_I(inode)->i_dquot;
1051 }
1052
1053 static const struct dquot_operations ext4_quota_operations = {
1054         .get_reserved_space = ext4_get_reserved_space,
1055         .write_dquot    = ext4_write_dquot,
1056         .acquire_dquot  = ext4_acquire_dquot,
1057         .release_dquot  = ext4_release_dquot,
1058         .mark_dirty     = ext4_mark_dquot_dirty,
1059         .write_info     = ext4_write_info,
1060         .alloc_dquot    = dquot_alloc,
1061         .destroy_dquot  = dquot_destroy,
1062 };
1063
1064 static const struct quotactl_ops ext4_qctl_operations = {
1065         .quota_on       = ext4_quota_on,
1066         .quota_off      = ext4_quota_off,
1067         .quota_sync     = dquot_quota_sync,
1068         .get_state      = dquot_get_state,
1069         .set_info       = dquot_set_dqinfo,
1070         .get_dqblk      = dquot_get_dqblk,
1071         .set_dqblk      = dquot_set_dqblk
1072 };
1073 #endif
1074
1075 static const struct super_operations ext4_sops = {
1076         .alloc_inode    = ext4_alloc_inode,
1077         .destroy_inode  = ext4_destroy_inode,
1078         .write_inode    = ext4_write_inode,
1079         .dirty_inode    = ext4_dirty_inode,
1080         .drop_inode     = ext4_drop_inode,
1081         .evict_inode    = ext4_evict_inode,
1082         .put_super      = ext4_put_super,
1083         .sync_fs        = ext4_sync_fs,
1084         .freeze_fs      = ext4_freeze,
1085         .unfreeze_fs    = ext4_unfreeze,
1086         .statfs         = ext4_statfs,
1087         .remount_fs     = ext4_remount,
1088         .show_options   = ext4_show_options,
1089 #ifdef CONFIG_QUOTA
1090         .quota_read     = ext4_quota_read,
1091         .quota_write    = ext4_quota_write,
1092         .get_dquots     = ext4_get_dquots,
1093 #endif
1094         .bdev_try_to_free_page = bdev_try_to_free_page,
1095 };
1096
1097 static const struct export_operations ext4_export_ops = {
1098         .fh_to_dentry = ext4_fh_to_dentry,
1099         .fh_to_parent = ext4_fh_to_parent,
1100         .get_parent = ext4_get_parent,
1101 };
1102
1103 enum {
1104         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1105         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1106         Opt_nouid32, Opt_debug, Opt_removed,
1107         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1108         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1109         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1110         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1111         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1112         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1113         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1114         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1115         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1116         Opt_usrquota, Opt_grpquota, Opt_i_version, Opt_dax,
1117         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1118         Opt_lazytime, Opt_nolazytime,
1119         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1120         Opt_inode_readahead_blks, Opt_journal_ioprio,
1121         Opt_dioread_nolock, Opt_dioread_lock,
1122         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1123         Opt_max_dir_size_kb, Opt_nojournal_checksum,
1124 };
1125
1126 static const match_table_t tokens = {
1127         {Opt_bsd_df, "bsddf"},
1128         {Opt_minix_df, "minixdf"},
1129         {Opt_grpid, "grpid"},
1130         {Opt_grpid, "bsdgroups"},
1131         {Opt_nogrpid, "nogrpid"},
1132         {Opt_nogrpid, "sysvgroups"},
1133         {Opt_resgid, "resgid=%u"},
1134         {Opt_resuid, "resuid=%u"},
1135         {Opt_sb, "sb=%u"},
1136         {Opt_err_cont, "errors=continue"},
1137         {Opt_err_panic, "errors=panic"},
1138         {Opt_err_ro, "errors=remount-ro"},
1139         {Opt_nouid32, "nouid32"},
1140         {Opt_debug, "debug"},
1141         {Opt_removed, "oldalloc"},
1142         {Opt_removed, "orlov"},
1143         {Opt_user_xattr, "user_xattr"},
1144         {Opt_nouser_xattr, "nouser_xattr"},
1145         {Opt_acl, "acl"},
1146         {Opt_noacl, "noacl"},
1147         {Opt_noload, "norecovery"},
1148         {Opt_noload, "noload"},
1149         {Opt_removed, "nobh"},
1150         {Opt_removed, "bh"},
1151         {Opt_commit, "commit=%u"},
1152         {Opt_min_batch_time, "min_batch_time=%u"},
1153         {Opt_max_batch_time, "max_batch_time=%u"},
1154         {Opt_journal_dev, "journal_dev=%u"},
1155         {Opt_journal_path, "journal_path=%s"},
1156         {Opt_journal_checksum, "journal_checksum"},
1157         {Opt_nojournal_checksum, "nojournal_checksum"},
1158         {Opt_journal_async_commit, "journal_async_commit"},
1159         {Opt_abort, "abort"},
1160         {Opt_data_journal, "data=journal"},
1161         {Opt_data_ordered, "data=ordered"},
1162         {Opt_data_writeback, "data=writeback"},
1163         {Opt_data_err_abort, "data_err=abort"},
1164         {Opt_data_err_ignore, "data_err=ignore"},
1165         {Opt_offusrjquota, "usrjquota="},
1166         {Opt_usrjquota, "usrjquota=%s"},
1167         {Opt_offgrpjquota, "grpjquota="},
1168         {Opt_grpjquota, "grpjquota=%s"},
1169         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1170         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1171         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1172         {Opt_grpquota, "grpquota"},
1173         {Opt_noquota, "noquota"},
1174         {Opt_quota, "quota"},
1175         {Opt_usrquota, "usrquota"},
1176         {Opt_barrier, "barrier=%u"},
1177         {Opt_barrier, "barrier"},
1178         {Opt_nobarrier, "nobarrier"},
1179         {Opt_i_version, "i_version"},
1180         {Opt_dax, "dax"},
1181         {Opt_stripe, "stripe=%u"},
1182         {Opt_delalloc, "delalloc"},
1183         {Opt_lazytime, "lazytime"},
1184         {Opt_nolazytime, "nolazytime"},
1185         {Opt_nodelalloc, "nodelalloc"},
1186         {Opt_removed, "mblk_io_submit"},
1187         {Opt_removed, "nomblk_io_submit"},
1188         {Opt_block_validity, "block_validity"},
1189         {Opt_noblock_validity, "noblock_validity"},
1190         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1191         {Opt_journal_ioprio, "journal_ioprio=%u"},
1192         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1193         {Opt_auto_da_alloc, "auto_da_alloc"},
1194         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1195         {Opt_dioread_nolock, "dioread_nolock"},
1196         {Opt_dioread_lock, "dioread_lock"},
1197         {Opt_discard, "discard"},
1198         {Opt_nodiscard, "nodiscard"},
1199         {Opt_init_itable, "init_itable=%u"},
1200         {Opt_init_itable, "init_itable"},
1201         {Opt_noinit_itable, "noinit_itable"},
1202         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1203         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1204         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1205         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1206         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1207         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1208         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1209         {Opt_err, NULL},
1210 };
1211
1212 static ext4_fsblk_t get_sb_block(void **data)
1213 {
1214         ext4_fsblk_t    sb_block;
1215         char            *options = (char *) *data;
1216
1217         if (!options || strncmp(options, "sb=", 3) != 0)
1218                 return 1;       /* Default location */
1219
1220         options += 3;
1221         /* TODO: use simple_strtoll with >32bit ext4 */
1222         sb_block = simple_strtoul(options, &options, 0);
1223         if (*options && *options != ',') {
1224                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1225                        (char *) *data);
1226                 return 1;
1227         }
1228         if (*options == ',')
1229                 options++;
1230         *data = (void *) options;
1231
1232         return sb_block;
1233 }
1234
1235 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1236 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1237         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1238
1239 #ifdef CONFIG_QUOTA
1240 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1241 {
1242         struct ext4_sb_info *sbi = EXT4_SB(sb);
1243         char *qname;
1244         int ret = -1;
1245
1246         if (sb_any_quota_loaded(sb) &&
1247                 !sbi->s_qf_names[qtype]) {
1248                 ext4_msg(sb, KERN_ERR,
1249                         "Cannot change journaled "
1250                         "quota options when quota turned on");
1251                 return -1;
1252         }
1253         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1254                 ext4_msg(sb, KERN_ERR, "Cannot set journaled quota options "
1255                          "when QUOTA feature is enabled");
1256                 return -1;
1257         }
1258         qname = match_strdup(args);
1259         if (!qname) {
1260                 ext4_msg(sb, KERN_ERR,
1261                         "Not enough memory for storing quotafile name");
1262                 return -1;
1263         }
1264         if (sbi->s_qf_names[qtype]) {
1265                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1266                         ret = 1;
1267                 else
1268                         ext4_msg(sb, KERN_ERR,
1269                                  "%s quota file already specified",
1270                                  QTYPE2NAME(qtype));
1271                 goto errout;
1272         }
1273         if (strchr(qname, '/')) {
1274                 ext4_msg(sb, KERN_ERR,
1275                         "quotafile must be on filesystem root");
1276                 goto errout;
1277         }
1278         sbi->s_qf_names[qtype] = qname;
1279         set_opt(sb, QUOTA);
1280         return 1;
1281 errout:
1282         kfree(qname);
1283         return ret;
1284 }
1285
1286 static int clear_qf_name(struct super_block *sb, int qtype)
1287 {
1288
1289         struct ext4_sb_info *sbi = EXT4_SB(sb);
1290
1291         if (sb_any_quota_loaded(sb) &&
1292                 sbi->s_qf_names[qtype]) {
1293                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1294                         " when quota turned on");
1295                 return -1;
1296         }
1297         kfree(sbi->s_qf_names[qtype]);
1298         sbi->s_qf_names[qtype] = NULL;
1299         return 1;
1300 }
1301 #endif
1302
1303 #define MOPT_SET        0x0001
1304 #define MOPT_CLEAR      0x0002
1305 #define MOPT_NOSUPPORT  0x0004
1306 #define MOPT_EXPLICIT   0x0008
1307 #define MOPT_CLEAR_ERR  0x0010
1308 #define MOPT_GTE0       0x0020
1309 #ifdef CONFIG_QUOTA
1310 #define MOPT_Q          0
1311 #define MOPT_QFMT       0x0040
1312 #else
1313 #define MOPT_Q          MOPT_NOSUPPORT
1314 #define MOPT_QFMT       MOPT_NOSUPPORT
1315 #endif
1316 #define MOPT_DATAJ      0x0080
1317 #define MOPT_NO_EXT2    0x0100
1318 #define MOPT_NO_EXT3    0x0200
1319 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1320 #define MOPT_STRING     0x0400
1321
1322 static const struct mount_opts {
1323         int     token;
1324         int     mount_opt;
1325         int     flags;
1326 } ext4_mount_opts[] = {
1327         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1328         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1329         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1330         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1331         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1332         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1333         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1334          MOPT_EXT4_ONLY | MOPT_SET},
1335         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1336          MOPT_EXT4_ONLY | MOPT_CLEAR},
1337         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1338         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1339         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1340          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1341         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1342          MOPT_EXT4_ONLY | MOPT_CLEAR},
1343         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1344          MOPT_EXT4_ONLY | MOPT_CLEAR},
1345         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1346          MOPT_EXT4_ONLY | MOPT_SET},
1347         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1348                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1349          MOPT_EXT4_ONLY | MOPT_SET},
1350         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1351         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1352         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1353         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1354         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1355          MOPT_NO_EXT2 | MOPT_SET},
1356         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1357          MOPT_NO_EXT2 | MOPT_CLEAR},
1358         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1359         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1360         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1361         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1362         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1363         {Opt_commit, 0, MOPT_GTE0},
1364         {Opt_max_batch_time, 0, MOPT_GTE0},
1365         {Opt_min_batch_time, 0, MOPT_GTE0},
1366         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1367         {Opt_init_itable, 0, MOPT_GTE0},
1368         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1369         {Opt_stripe, 0, MOPT_GTE0},
1370         {Opt_resuid, 0, MOPT_GTE0},
1371         {Opt_resgid, 0, MOPT_GTE0},
1372         {Opt_journal_dev, 0, MOPT_GTE0},
1373         {Opt_journal_path, 0, MOPT_STRING},
1374         {Opt_journal_ioprio, 0, MOPT_GTE0},
1375         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1376         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1377         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1378          MOPT_NO_EXT2 | MOPT_DATAJ},
1379         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1380         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1381 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1382         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1383         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1384 #else
1385         {Opt_acl, 0, MOPT_NOSUPPORT},
1386         {Opt_noacl, 0, MOPT_NOSUPPORT},
1387 #endif
1388         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1389         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1390         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1391         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1392                                                         MOPT_SET | MOPT_Q},
1393         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1394                                                         MOPT_SET | MOPT_Q},
1395         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1396                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1397         {Opt_usrjquota, 0, MOPT_Q},
1398         {Opt_grpjquota, 0, MOPT_Q},
1399         {Opt_offusrjquota, 0, MOPT_Q},
1400         {Opt_offgrpjquota, 0, MOPT_Q},
1401         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1402         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1403         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1404         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1405         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1406         {Opt_err, 0, 0}
1407 };
1408
1409 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1410                             substring_t *args, unsigned long *journal_devnum,
1411                             unsigned int *journal_ioprio, int is_remount)
1412 {
1413         struct ext4_sb_info *sbi = EXT4_SB(sb);
1414         const struct mount_opts *m;
1415         kuid_t uid;
1416         kgid_t gid;
1417         int arg = 0;
1418
1419 #ifdef CONFIG_QUOTA
1420         if (token == Opt_usrjquota)
1421                 return set_qf_name(sb, USRQUOTA, &args[0]);
1422         else if (token == Opt_grpjquota)
1423                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1424         else if (token == Opt_offusrjquota)
1425                 return clear_qf_name(sb, USRQUOTA);
1426         else if (token == Opt_offgrpjquota)
1427                 return clear_qf_name(sb, GRPQUOTA);
1428 #endif
1429         switch (token) {
1430         case Opt_noacl:
1431         case Opt_nouser_xattr:
1432                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1433                 break;
1434         case Opt_sb:
1435                 return 1;       /* handled by get_sb_block() */
1436         case Opt_removed:
1437                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1438                 return 1;
1439         case Opt_abort:
1440                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1441                 return 1;
1442         case Opt_i_version:
1443                 sb->s_flags |= MS_I_VERSION;
1444                 return 1;
1445         case Opt_lazytime:
1446                 sb->s_flags |= MS_LAZYTIME;
1447                 return 1;
1448         case Opt_nolazytime:
1449                 sb->s_flags &= ~MS_LAZYTIME;
1450                 return 1;
1451         }
1452
1453         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1454                 if (token == m->token)
1455                         break;
1456
1457         if (m->token == Opt_err) {
1458                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1459                          "or missing value", opt);
1460                 return -1;
1461         }
1462
1463         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1464                 ext4_msg(sb, KERN_ERR,
1465                          "Mount option \"%s\" incompatible with ext2", opt);
1466                 return -1;
1467         }
1468         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1469                 ext4_msg(sb, KERN_ERR,
1470                          "Mount option \"%s\" incompatible with ext3", opt);
1471                 return -1;
1472         }
1473
1474         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1475                 return -1;
1476         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1477                 return -1;
1478         if (m->flags & MOPT_EXPLICIT)
1479                 set_opt2(sb, EXPLICIT_DELALLOC);
1480         if (m->flags & MOPT_CLEAR_ERR)
1481                 clear_opt(sb, ERRORS_MASK);
1482         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1483                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1484                          "options when quota turned on");
1485                 return -1;
1486         }
1487
1488         if (m->flags & MOPT_NOSUPPORT) {
1489                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1490         } else if (token == Opt_commit) {
1491                 if (arg == 0)
1492                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1493                 sbi->s_commit_interval = HZ * arg;
1494         } else if (token == Opt_max_batch_time) {
1495                 sbi->s_max_batch_time = arg;
1496         } else if (token == Opt_min_batch_time) {
1497                 sbi->s_min_batch_time = arg;
1498         } else if (token == Opt_inode_readahead_blks) {
1499                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1500                         ext4_msg(sb, KERN_ERR,
1501                                  "EXT4-fs: inode_readahead_blks must be "
1502                                  "0 or a power of 2 smaller than 2^31");
1503                         return -1;
1504                 }
1505                 sbi->s_inode_readahead_blks = arg;
1506         } else if (token == Opt_init_itable) {
1507                 set_opt(sb, INIT_INODE_TABLE);
1508                 if (!args->from)
1509                         arg = EXT4_DEF_LI_WAIT_MULT;
1510                 sbi->s_li_wait_mult = arg;
1511         } else if (token == Opt_max_dir_size_kb) {
1512                 sbi->s_max_dir_size_kb = arg;
1513         } else if (token == Opt_stripe) {
1514                 sbi->s_stripe = arg;
1515         } else if (token == Opt_resuid) {
1516                 uid = make_kuid(current_user_ns(), arg);
1517                 if (!uid_valid(uid)) {
1518                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1519                         return -1;
1520                 }
1521                 sbi->s_resuid = uid;
1522         } else if (token == Opt_resgid) {
1523                 gid = make_kgid(current_user_ns(), arg);
1524                 if (!gid_valid(gid)) {
1525                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1526                         return -1;
1527                 }
1528                 sbi->s_resgid = gid;
1529         } else if (token == Opt_journal_dev) {
1530                 if (is_remount) {
1531                         ext4_msg(sb, KERN_ERR,
1532                                  "Cannot specify journal on remount");
1533                         return -1;
1534                 }
1535                 *journal_devnum = arg;
1536         } else if (token == Opt_journal_path) {
1537                 char *journal_path;
1538                 struct inode *journal_inode;
1539                 struct path path;
1540                 int error;
1541
1542                 if (is_remount) {
1543                         ext4_msg(sb, KERN_ERR,
1544                                  "Cannot specify journal on remount");
1545                         return -1;
1546                 }
1547                 journal_path = match_strdup(&args[0]);
1548                 if (!journal_path) {
1549                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1550                                 "journal device string");
1551                         return -1;
1552                 }
1553
1554                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1555                 if (error) {
1556                         ext4_msg(sb, KERN_ERR, "error: could not find "
1557                                 "journal device path: error %d", error);
1558                         kfree(journal_path);
1559                         return -1;
1560                 }
1561
1562                 journal_inode = d_inode(path.dentry);
1563                 if (!S_ISBLK(journal_inode->i_mode)) {
1564                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1565                                 "is not a block device", journal_path);
1566                         path_put(&path);
1567                         kfree(journal_path);
1568                         return -1;
1569                 }
1570
1571                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1572                 path_put(&path);
1573                 kfree(journal_path);
1574         } else if (token == Opt_journal_ioprio) {
1575                 if (arg > 7) {
1576                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1577                                  " (must be 0-7)");
1578                         return -1;
1579                 }
1580                 *journal_ioprio =
1581                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1582         } else if (token == Opt_test_dummy_encryption) {
1583 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1584                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1585                 ext4_msg(sb, KERN_WARNING,
1586                          "Test dummy encryption mode enabled");
1587 #else
1588                 ext4_msg(sb, KERN_WARNING,
1589                          "Test dummy encryption mount option ignored");
1590 #endif
1591         } else if (m->flags & MOPT_DATAJ) {
1592                 if (is_remount) {
1593                         if (!sbi->s_journal)
1594                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1595                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1596                                 ext4_msg(sb, KERN_ERR,
1597                                          "Cannot change data mode on remount");
1598                                 return -1;
1599                         }
1600                 } else {
1601                         clear_opt(sb, DATA_FLAGS);
1602                         sbi->s_mount_opt |= m->mount_opt;
1603                 }
1604 #ifdef CONFIG_QUOTA
1605         } else if (m->flags & MOPT_QFMT) {
1606                 if (sb_any_quota_loaded(sb) &&
1607                     sbi->s_jquota_fmt != m->mount_opt) {
1608                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1609                                  "quota options when quota turned on");
1610                         return -1;
1611                 }
1612                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
1613                                                EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1614                         ext4_msg(sb, KERN_ERR,
1615                                  "Cannot set journaled quota options "
1616                                  "when QUOTA feature is enabled");
1617                         return -1;
1618                 }
1619                 sbi->s_jquota_fmt = m->mount_opt;
1620 #endif
1621 #ifndef CONFIG_FS_DAX
1622         } else if (token == Opt_dax) {
1623                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1624                 return -1;
1625 #endif
1626         } else {
1627                 if (!args->from)
1628                         arg = 1;
1629                 if (m->flags & MOPT_CLEAR)
1630                         arg = !arg;
1631                 else if (unlikely(!(m->flags & MOPT_SET))) {
1632                         ext4_msg(sb, KERN_WARNING,
1633                                  "buggy handling of option %s", opt);
1634                         WARN_ON(1);
1635                         return -1;
1636                 }
1637                 if (arg != 0)
1638                         sbi->s_mount_opt |= m->mount_opt;
1639                 else
1640                         sbi->s_mount_opt &= ~m->mount_opt;
1641         }
1642         return 1;
1643 }
1644
1645 static int parse_options(char *options, struct super_block *sb,
1646                          unsigned long *journal_devnum,
1647                          unsigned int *journal_ioprio,
1648                          int is_remount)
1649 {
1650         struct ext4_sb_info *sbi = EXT4_SB(sb);
1651         char *p;
1652         substring_t args[MAX_OPT_ARGS];
1653         int token;
1654
1655         if (!options)
1656                 return 1;
1657
1658         while ((p = strsep(&options, ",")) != NULL) {
1659                 if (!*p)
1660                         continue;
1661                 /*
1662                  * Initialize args struct so we know whether arg was
1663                  * found; some options take optional arguments.
1664                  */
1665                 args[0].to = args[0].from = NULL;
1666                 token = match_token(p, tokens, args);
1667                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1668                                      journal_ioprio, is_remount) < 0)
1669                         return 0;
1670         }
1671 #ifdef CONFIG_QUOTA
1672         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
1673             (test_opt(sb, USRQUOTA) || test_opt(sb, GRPQUOTA))) {
1674                 ext4_msg(sb, KERN_ERR, "Cannot set quota options when QUOTA "
1675                          "feature is enabled");
1676                 return 0;
1677         }
1678         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1679                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1680                         clear_opt(sb, USRQUOTA);
1681
1682                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1683                         clear_opt(sb, GRPQUOTA);
1684
1685                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1686                         ext4_msg(sb, KERN_ERR, "old and new quota "
1687                                         "format mixing");
1688                         return 0;
1689                 }
1690
1691                 if (!sbi->s_jquota_fmt) {
1692                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1693                                         "not specified");
1694                         return 0;
1695                 }
1696         }
1697 #endif
1698         if (test_opt(sb, DIOREAD_NOLOCK)) {
1699                 int blocksize =
1700                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1701
1702                 if (blocksize < PAGE_CACHE_SIZE) {
1703                         ext4_msg(sb, KERN_ERR, "can't mount with "
1704                                  "dioread_nolock if block size != PAGE_SIZE");
1705                         return 0;
1706                 }
1707         }
1708         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
1709             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
1710                 ext4_msg(sb, KERN_ERR, "can't mount with journal_async_commit "
1711                          "in data=ordered mode");
1712                 return 0;
1713         }
1714         return 1;
1715 }
1716
1717 static inline void ext4_show_quota_options(struct seq_file *seq,
1718                                            struct super_block *sb)
1719 {
1720 #if defined(CONFIG_QUOTA)
1721         struct ext4_sb_info *sbi = EXT4_SB(sb);
1722
1723         if (sbi->s_jquota_fmt) {
1724                 char *fmtname = "";
1725
1726                 switch (sbi->s_jquota_fmt) {
1727                 case QFMT_VFS_OLD:
1728                         fmtname = "vfsold";
1729                         break;
1730                 case QFMT_VFS_V0:
1731                         fmtname = "vfsv0";
1732                         break;
1733                 case QFMT_VFS_V1:
1734                         fmtname = "vfsv1";
1735                         break;
1736                 }
1737                 seq_printf(seq, ",jqfmt=%s", fmtname);
1738         }
1739
1740         if (sbi->s_qf_names[USRQUOTA])
1741                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1742
1743         if (sbi->s_qf_names[GRPQUOTA])
1744                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1745 #endif
1746 }
1747
1748 static const char *token2str(int token)
1749 {
1750         const struct match_token *t;
1751
1752         for (t = tokens; t->token != Opt_err; t++)
1753                 if (t->token == token && !strchr(t->pattern, '='))
1754                         break;
1755         return t->pattern;
1756 }
1757
1758 /*
1759  * Show an option if
1760  *  - it's set to a non-default value OR
1761  *  - if the per-sb default is different from the global default
1762  */
1763 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1764                               int nodefs)
1765 {
1766         struct ext4_sb_info *sbi = EXT4_SB(sb);
1767         struct ext4_super_block *es = sbi->s_es;
1768         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1769         const struct mount_opts *m;
1770         char sep = nodefs ? '\n' : ',';
1771
1772 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1773 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1774
1775         if (sbi->s_sb_block != 1)
1776                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1777
1778         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1779                 int want_set = m->flags & MOPT_SET;
1780                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1781                     (m->flags & MOPT_CLEAR_ERR))
1782                         continue;
1783                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1784                         continue; /* skip if same as the default */
1785                 if ((want_set &&
1786                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1787                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1788                         continue; /* select Opt_noFoo vs Opt_Foo */
1789                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1790         }
1791
1792         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1793             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1794                 SEQ_OPTS_PRINT("resuid=%u",
1795                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1796         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1797             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1798                 SEQ_OPTS_PRINT("resgid=%u",
1799                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1800         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1801         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1802                 SEQ_OPTS_PUTS("errors=remount-ro");
1803         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1804                 SEQ_OPTS_PUTS("errors=continue");
1805         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1806                 SEQ_OPTS_PUTS("errors=panic");
1807         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1808                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1809         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1810                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1811         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1812                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1813         if (sb->s_flags & MS_I_VERSION)
1814                 SEQ_OPTS_PUTS("i_version");
1815         if (nodefs || sbi->s_stripe)
1816                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1817         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1818                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1819                         SEQ_OPTS_PUTS("data=journal");
1820                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1821                         SEQ_OPTS_PUTS("data=ordered");
1822                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1823                         SEQ_OPTS_PUTS("data=writeback");
1824         }
1825         if (nodefs ||
1826             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1827                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1828                                sbi->s_inode_readahead_blks);
1829
1830         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1831                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1832                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1833         if (nodefs || sbi->s_max_dir_size_kb)
1834                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
1835
1836         ext4_show_quota_options(seq, sb);
1837         return 0;
1838 }
1839
1840 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1841 {
1842         return _ext4_show_options(seq, root->d_sb, 0);
1843 }
1844
1845 static int options_seq_show(struct seq_file *seq, void *offset)
1846 {
1847         struct super_block *sb = seq->private;
1848         int rc;
1849
1850         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1851         rc = _ext4_show_options(seq, sb, 1);
1852         seq_puts(seq, "\n");
1853         return rc;
1854 }
1855
1856 static int options_open_fs(struct inode *inode, struct file *file)
1857 {
1858         return single_open(file, options_seq_show, PDE_DATA(inode));
1859 }
1860
1861 static const struct file_operations ext4_seq_options_fops = {
1862         .owner = THIS_MODULE,
1863         .open = options_open_fs,
1864         .read = seq_read,
1865         .llseek = seq_lseek,
1866         .release = single_release,
1867 };
1868
1869 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1870                             int read_only)
1871 {
1872         struct ext4_sb_info *sbi = EXT4_SB(sb);
1873         int res = 0;
1874
1875         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1876                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1877                          "forcing read-only mode");
1878                 res = MS_RDONLY;
1879         }
1880         if (read_only)
1881                 goto done;
1882         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1883                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1884                          "running e2fsck is recommended");
1885         else if (sbi->s_mount_state & EXT4_ERROR_FS)
1886                 ext4_msg(sb, KERN_WARNING,
1887                          "warning: mounting fs with errors, "
1888                          "running e2fsck is recommended");
1889         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1890                  le16_to_cpu(es->s_mnt_count) >=
1891                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1892                 ext4_msg(sb, KERN_WARNING,
1893                          "warning: maximal mount count reached, "
1894                          "running e2fsck is recommended");
1895         else if (le32_to_cpu(es->s_checkinterval) &&
1896                 (le32_to_cpu(es->s_lastcheck) +
1897                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1898                 ext4_msg(sb, KERN_WARNING,
1899                          "warning: checktime reached, "
1900                          "running e2fsck is recommended");
1901         if (!sbi->s_journal)
1902                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1903         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1904                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1905         le16_add_cpu(&es->s_mnt_count, 1);
1906         es->s_mtime = cpu_to_le32(get_seconds());
1907         ext4_update_dynamic_rev(sb);
1908         if (sbi->s_journal)
1909                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1910
1911         ext4_commit_super(sb, 1);
1912 done:
1913         if (test_opt(sb, DEBUG))
1914                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1915                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1916                         sb->s_blocksize,
1917                         sbi->s_groups_count,
1918                         EXT4_BLOCKS_PER_GROUP(sb),
1919                         EXT4_INODES_PER_GROUP(sb),
1920                         sbi->s_mount_opt, sbi->s_mount_opt2);
1921
1922         cleancache_init_fs(sb);
1923         return res;
1924 }
1925
1926 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
1927 {
1928         struct ext4_sb_info *sbi = EXT4_SB(sb);
1929         struct flex_groups *new_groups;
1930         int size;
1931
1932         if (!sbi->s_log_groups_per_flex)
1933                 return 0;
1934
1935         size = ext4_flex_group(sbi, ngroup - 1) + 1;
1936         if (size <= sbi->s_flex_groups_allocated)
1937                 return 0;
1938
1939         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
1940         new_groups = ext4_kvzalloc(size, GFP_KERNEL);
1941         if (!new_groups) {
1942                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
1943                          size / (int) sizeof(struct flex_groups));
1944                 return -ENOMEM;
1945         }
1946
1947         if (sbi->s_flex_groups) {
1948                 memcpy(new_groups, sbi->s_flex_groups,
1949                        (sbi->s_flex_groups_allocated *
1950                         sizeof(struct flex_groups)));
1951                 kvfree(sbi->s_flex_groups);
1952         }
1953         sbi->s_flex_groups = new_groups;
1954         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
1955         return 0;
1956 }
1957
1958 static int ext4_fill_flex_info(struct super_block *sb)
1959 {
1960         struct ext4_sb_info *sbi = EXT4_SB(sb);
1961         struct ext4_group_desc *gdp = NULL;
1962         ext4_group_t flex_group;
1963         int i, err;
1964
1965         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1966         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1967                 sbi->s_log_groups_per_flex = 0;
1968                 return 1;
1969         }
1970
1971         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
1972         if (err)
1973                 goto failed;
1974
1975         for (i = 0; i < sbi->s_groups_count; i++) {
1976                 gdp = ext4_get_group_desc(sb, i, NULL);
1977
1978                 flex_group = ext4_flex_group(sbi, i);
1979                 atomic_add(ext4_free_inodes_count(sb, gdp),
1980                            &sbi->s_flex_groups[flex_group].free_inodes);
1981                 atomic64_add(ext4_free_group_clusters(sb, gdp),
1982                              &sbi->s_flex_groups[flex_group].free_clusters);
1983                 atomic_add(ext4_used_dirs_count(sb, gdp),
1984                            &sbi->s_flex_groups[flex_group].used_dirs);
1985         }
1986
1987         return 1;
1988 failed:
1989         return 0;
1990 }
1991
1992 static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1993                                    struct ext4_group_desc *gdp)
1994 {
1995         int offset;
1996         __u16 crc = 0;
1997         __le32 le_group = cpu_to_le32(block_group);
1998
1999         if (ext4_has_metadata_csum(sbi->s_sb)) {
2000                 /* Use new metadata_csum algorithm */
2001                 __le16 save_csum;
2002                 __u32 csum32;
2003
2004                 save_csum = gdp->bg_checksum;
2005                 gdp->bg_checksum = 0;
2006                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2007                                      sizeof(le_group));
2008                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
2009                                      sbi->s_desc_size);
2010                 gdp->bg_checksum = save_csum;
2011
2012                 crc = csum32 & 0xFFFF;
2013                 goto out;
2014         }
2015
2016         /* old crc16 code */
2017         if (!(sbi->s_es->s_feature_ro_compat &
2018               cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)))
2019                 return 0;
2020
2021         offset = offsetof(struct ext4_group_desc, bg_checksum);
2022
2023         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2024         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2025         crc = crc16(crc, (__u8 *)gdp, offset);
2026         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2027         /* for checksum of struct ext4_group_desc do the rest...*/
2028         if ((sbi->s_es->s_feature_incompat &
2029              cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2030             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2031                 crc = crc16(crc, (__u8 *)gdp + offset,
2032                             le16_to_cpu(sbi->s_es->s_desc_size) -
2033                                 offset);
2034
2035 out:
2036         return cpu_to_le16(crc);
2037 }
2038
2039 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2040                                 struct ext4_group_desc *gdp)
2041 {
2042         if (ext4_has_group_desc_csum(sb) &&
2043             (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
2044                                                       block_group, gdp)))
2045                 return 0;
2046
2047         return 1;
2048 }
2049
2050 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2051                               struct ext4_group_desc *gdp)
2052 {
2053         if (!ext4_has_group_desc_csum(sb))
2054                 return;
2055         gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
2056 }
2057
2058 /* Called at mount-time, super-block is locked */
2059 static int ext4_check_descriptors(struct super_block *sb,
2060                                   ext4_group_t *first_not_zeroed)
2061 {
2062         struct ext4_sb_info *sbi = EXT4_SB(sb);
2063         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2064         ext4_fsblk_t last_block;
2065         ext4_fsblk_t block_bitmap;
2066         ext4_fsblk_t inode_bitmap;
2067         ext4_fsblk_t inode_table;
2068         int flexbg_flag = 0;
2069         ext4_group_t i, grp = sbi->s_groups_count;
2070
2071         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2072                 flexbg_flag = 1;
2073
2074         ext4_debug("Checking group descriptors");
2075
2076         for (i = 0; i < sbi->s_groups_count; i++) {
2077                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2078
2079                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2080                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2081                 else
2082                         last_block = first_block +
2083                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2084
2085                 if ((grp == sbi->s_groups_count) &&
2086                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2087                         grp = i;
2088
2089                 block_bitmap = ext4_block_bitmap(sb, gdp);
2090                 if (block_bitmap < first_block || block_bitmap > last_block) {
2091                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2092                                "Block bitmap for group %u not in group "
2093                                "(block %llu)!", i, block_bitmap);
2094                         return 0;
2095                 }
2096                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2097                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2098                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2099                                "Inode bitmap for group %u not in group "
2100                                "(block %llu)!", i, inode_bitmap);
2101                         return 0;
2102                 }
2103                 inode_table = ext4_inode_table(sb, gdp);
2104                 if (inode_table < first_block ||
2105                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2106                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2107                                "Inode table for group %u not in group "
2108                                "(block %llu)!", i, inode_table);
2109                         return 0;
2110                 }
2111                 ext4_lock_group(sb, i);
2112                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2113                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2114                                  "Checksum for group %u failed (%u!=%u)",
2115                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2116                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2117                         if (!(sb->s_flags & MS_RDONLY)) {
2118                                 ext4_unlock_group(sb, i);
2119                                 return 0;
2120                         }
2121                 }
2122                 ext4_unlock_group(sb, i);
2123                 if (!flexbg_flag)
2124                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2125         }
2126         if (NULL != first_not_zeroed)
2127                 *first_not_zeroed = grp;
2128         return 1;
2129 }
2130
2131 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2132  * the superblock) which were deleted from all directories, but held open by
2133  * a process at the time of a crash.  We walk the list and try to delete these
2134  * inodes at recovery time (only with a read-write filesystem).
2135  *
2136  * In order to keep the orphan inode chain consistent during traversal (in
2137  * case of crash during recovery), we link each inode into the superblock
2138  * orphan list_head and handle it the same way as an inode deletion during
2139  * normal operation (which journals the operations for us).
2140  *
2141  * We only do an iget() and an iput() on each inode, which is very safe if we
2142  * accidentally point at an in-use or already deleted inode.  The worst that
2143  * can happen in this case is that we get a "bit already cleared" message from
2144  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2145  * e2fsck was run on this filesystem, and it must have already done the orphan
2146  * inode cleanup for us, so we can safely abort without any further action.
2147  */
2148 static void ext4_orphan_cleanup(struct super_block *sb,
2149                                 struct ext4_super_block *es)
2150 {
2151         unsigned int s_flags = sb->s_flags;
2152         int nr_orphans = 0, nr_truncates = 0;
2153 #ifdef CONFIG_QUOTA
2154         int i;
2155 #endif
2156         if (!es->s_last_orphan) {
2157                 jbd_debug(4, "no orphan inodes to clean up\n");
2158                 return;
2159         }
2160
2161         if (bdev_read_only(sb->s_bdev)) {
2162                 ext4_msg(sb, KERN_ERR, "write access "
2163                         "unavailable, skipping orphan cleanup");
2164                 return;
2165         }
2166
2167         /* Check if feature set would not allow a r/w mount */
2168         if (!ext4_feature_set_ok(sb, 0)) {
2169                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2170                          "unknown ROCOMPAT features");
2171                 return;
2172         }
2173
2174         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2175                 /* don't clear list on RO mount w/ errors */
2176                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2177                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2178                                   "clearing orphan list.\n");
2179                         es->s_last_orphan = 0;
2180                 }
2181                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2182                 return;
2183         }
2184
2185         if (s_flags & MS_RDONLY) {
2186                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2187                 sb->s_flags &= ~MS_RDONLY;
2188         }
2189 #ifdef CONFIG_QUOTA
2190         /* Needed for iput() to work correctly and not trash data */
2191         sb->s_flags |= MS_ACTIVE;
2192         /* Turn on quotas so that they are updated correctly */
2193         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2194                 if (EXT4_SB(sb)->s_qf_names[i]) {
2195                         int ret = ext4_quota_on_mount(sb, i);
2196                         if (ret < 0)
2197                                 ext4_msg(sb, KERN_ERR,
2198                                         "Cannot turn on journaled "
2199                                         "quota: error %d", ret);
2200                 }
2201         }
2202 #endif
2203
2204         while (es->s_last_orphan) {
2205                 struct inode *inode;
2206
2207                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2208                 if (IS_ERR(inode)) {
2209                         es->s_last_orphan = 0;
2210                         break;
2211                 }
2212
2213                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2214                 dquot_initialize(inode);
2215                 if (inode->i_nlink) {
2216                         if (test_opt(sb, DEBUG))
2217                                 ext4_msg(sb, KERN_DEBUG,
2218                                         "%s: truncating inode %lu to %lld bytes",
2219                                         __func__, inode->i_ino, inode->i_size);
2220                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2221                                   inode->i_ino, inode->i_size);
2222                         mutex_lock(&inode->i_mutex);
2223                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2224                         ext4_truncate(inode);
2225                         mutex_unlock(&inode->i_mutex);
2226                         nr_truncates++;
2227                 } else {
2228                         if (test_opt(sb, DEBUG))
2229                                 ext4_msg(sb, KERN_DEBUG,
2230                                         "%s: deleting unreferenced inode %lu",
2231                                         __func__, inode->i_ino);
2232                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2233                                   inode->i_ino);
2234                         nr_orphans++;
2235                 }
2236                 iput(inode);  /* The delete magic happens here! */
2237         }
2238
2239 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2240
2241         if (nr_orphans)
2242                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2243                        PLURAL(nr_orphans));
2244         if (nr_truncates)
2245                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2246                        PLURAL(nr_truncates));
2247 #ifdef CONFIG_QUOTA
2248         /* Turn quotas off */
2249         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2250                 if (sb_dqopt(sb)->files[i])
2251                         dquot_quota_off(sb, i);
2252         }
2253 #endif
2254         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2255 }
2256
2257 /*
2258  * Maximal extent format file size.
2259  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2260  * extent format containers, within a sector_t, and within i_blocks
2261  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2262  * so that won't be a limiting factor.
2263  *
2264  * However there is other limiting factor. We do store extents in the form
2265  * of starting block and length, hence the resulting length of the extent
2266  * covering maximum file size must fit into on-disk format containers as
2267  * well. Given that length is always by 1 unit bigger than max unit (because
2268  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2269  *
2270  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2271  */
2272 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2273 {
2274         loff_t res;
2275         loff_t upper_limit = MAX_LFS_FILESIZE;
2276
2277         /* small i_blocks in vfs inode? */
2278         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2279                 /*
2280                  * CONFIG_LBDAF is not enabled implies the inode
2281                  * i_block represent total blocks in 512 bytes
2282                  * 32 == size of vfs inode i_blocks * 8
2283                  */
2284                 upper_limit = (1LL << 32) - 1;
2285
2286                 /* total blocks in file system block size */
2287                 upper_limit >>= (blkbits - 9);
2288                 upper_limit <<= blkbits;
2289         }
2290
2291         /*
2292          * 32-bit extent-start container, ee_block. We lower the maxbytes
2293          * by one fs block, so ee_len can cover the extent of maximum file
2294          * size
2295          */
2296         res = (1LL << 32) - 1;
2297         res <<= blkbits;
2298
2299         /* Sanity check against vm- & vfs- imposed limits */
2300         if (res > upper_limit)
2301                 res = upper_limit;
2302
2303         return res;
2304 }
2305
2306 /*
2307  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2308  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2309  * We need to be 1 filesystem block less than the 2^48 sector limit.
2310  */
2311 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2312 {
2313         loff_t res = EXT4_NDIR_BLOCKS;
2314         int meta_blocks;
2315         loff_t upper_limit;
2316         /* This is calculated to be the largest file size for a dense, block
2317          * mapped file such that the file's total number of 512-byte sectors,
2318          * including data and all indirect blocks, does not exceed (2^48 - 1).
2319          *
2320          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2321          * number of 512-byte sectors of the file.
2322          */
2323
2324         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2325                 /*
2326                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2327                  * the inode i_block field represents total file blocks in
2328                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2329                  */
2330                 upper_limit = (1LL << 32) - 1;
2331
2332                 /* total blocks in file system block size */
2333                 upper_limit >>= (bits - 9);
2334
2335         } else {
2336                 /*
2337                  * We use 48 bit ext4_inode i_blocks
2338                  * With EXT4_HUGE_FILE_FL set the i_blocks
2339                  * represent total number of blocks in
2340                  * file system block size
2341                  */
2342                 upper_limit = (1LL << 48) - 1;
2343
2344         }
2345
2346         /* indirect blocks */
2347         meta_blocks = 1;
2348         /* double indirect blocks */
2349         meta_blocks += 1 + (1LL << (bits-2));
2350         /* tripple indirect blocks */
2351         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2352
2353         upper_limit -= meta_blocks;
2354         upper_limit <<= bits;
2355
2356         res += 1LL << (bits-2);
2357         res += 1LL << (2*(bits-2));
2358         res += 1LL << (3*(bits-2));
2359         res <<= bits;
2360         if (res > upper_limit)
2361                 res = upper_limit;
2362
2363         if (res > MAX_LFS_FILESIZE)
2364                 res = MAX_LFS_FILESIZE;
2365
2366         return res;
2367 }
2368
2369 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2370                                    ext4_fsblk_t logical_sb_block, int nr)
2371 {
2372         struct ext4_sb_info *sbi = EXT4_SB(sb);
2373         ext4_group_t bg, first_meta_bg;
2374         int has_super = 0;
2375
2376         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2377
2378         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2379             nr < first_meta_bg)
2380                 return logical_sb_block + nr + 1;
2381         bg = sbi->s_desc_per_block * nr;
2382         if (ext4_bg_has_super(sb, bg))
2383                 has_super = 1;
2384
2385         /*
2386          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2387          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2388          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2389          * compensate.
2390          */
2391         if (sb->s_blocksize == 1024 && nr == 0 &&
2392             le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) == 0)
2393                 has_super++;
2394
2395         return (has_super + ext4_group_first_block_no(sb, bg));
2396 }
2397
2398 /**
2399  * ext4_get_stripe_size: Get the stripe size.
2400  * @sbi: In memory super block info
2401  *
2402  * If we have specified it via mount option, then
2403  * use the mount option value. If the value specified at mount time is
2404  * greater than the blocks per group use the super block value.
2405  * If the super block value is greater than blocks per group return 0.
2406  * Allocator needs it be less than blocks per group.
2407  *
2408  */
2409 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2410 {
2411         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2412         unsigned long stripe_width =
2413                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2414         int ret;
2415
2416         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2417                 ret = sbi->s_stripe;
2418         else if (stripe_width <= sbi->s_blocks_per_group)
2419                 ret = stripe_width;
2420         else if (stride <= sbi->s_blocks_per_group)
2421                 ret = stride;
2422         else
2423                 ret = 0;
2424
2425         /*
2426          * If the stripe width is 1, this makes no sense and
2427          * we set it to 0 to turn off stripe handling code.
2428          */
2429         if (ret <= 1)
2430                 ret = 0;
2431
2432         return ret;
2433 }
2434
2435 /* sysfs supprt */
2436
2437 struct ext4_attr {
2438         struct attribute attr;
2439         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2440         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2441                          const char *, size_t);
2442         union {
2443                 int offset;
2444                 int deprecated_val;
2445         } u;
2446 };
2447
2448 static int parse_strtoull(const char *buf,
2449                 unsigned long long max, unsigned long long *value)
2450 {
2451         int ret;
2452
2453         ret = kstrtoull(skip_spaces(buf), 0, value);
2454         if (!ret && *value > max)
2455                 ret = -EINVAL;
2456         return ret;
2457 }
2458
2459 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2460                                               struct ext4_sb_info *sbi,
2461                                               char *buf)
2462 {
2463         return snprintf(buf, PAGE_SIZE, "%llu\n",
2464                 (s64) EXT4_C2B(sbi,
2465                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2466 }
2467
2468 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2469                                          struct ext4_sb_info *sbi, char *buf)
2470 {
2471         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2472
2473         if (!sb->s_bdev->bd_part)
2474                 return snprintf(buf, PAGE_SIZE, "0\n");
2475         return snprintf(buf, PAGE_SIZE, "%lu\n",
2476                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2477                          sbi->s_sectors_written_start) >> 1);
2478 }
2479
2480 static ssize_t lifetime_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, "%llu\n",
2488                         (unsigned long long)(sbi->s_kbytes_written +
2489                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2490                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2491 }
2492
2493 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2494                                           struct ext4_sb_info *sbi,
2495                                           const char *buf, size_t count)
2496 {
2497         unsigned long t;
2498         int ret;
2499
2500         ret = kstrtoul(skip_spaces(buf), 0, &t);
2501         if (ret)
2502                 return ret;
2503
2504         if (t && (!is_power_of_2(t) || t > 0x40000000))
2505                 return -EINVAL;
2506
2507         sbi->s_inode_readahead_blks = t;
2508         return count;
2509 }
2510
2511 static ssize_t sbi_ui_show(struct ext4_attr *a,
2512                            struct ext4_sb_info *sbi, char *buf)
2513 {
2514         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
2515
2516         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2517 }
2518
2519 static ssize_t sbi_ui_store(struct ext4_attr *a,
2520                             struct ext4_sb_info *sbi,
2521                             const char *buf, size_t count)
2522 {
2523         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
2524         unsigned long t;
2525         int ret;
2526
2527         ret = kstrtoul(skip_spaces(buf), 0, &t);
2528         if (ret)
2529                 return ret;
2530         *ui = t;
2531         return count;
2532 }
2533
2534 static ssize_t es_ui_show(struct ext4_attr *a,
2535                            struct ext4_sb_info *sbi, char *buf)
2536 {
2537
2538         unsigned int *ui = (unsigned int *) (((char *) sbi->s_es) +
2539                            a->u.offset);
2540
2541         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2542 }
2543
2544 static ssize_t reserved_clusters_show(struct ext4_attr *a,
2545                                   struct ext4_sb_info *sbi, char *buf)
2546 {
2547         return snprintf(buf, PAGE_SIZE, "%llu\n",
2548                 (unsigned long long) atomic64_read(&sbi->s_resv_clusters));
2549 }
2550
2551 static ssize_t reserved_clusters_store(struct ext4_attr *a,
2552                                    struct ext4_sb_info *sbi,
2553                                    const char *buf, size_t count)
2554 {
2555         unsigned long long val;
2556         int ret;
2557
2558         if (parse_strtoull(buf, -1ULL, &val))
2559                 return -EINVAL;
2560         ret = ext4_reserve_clusters(sbi, val);
2561
2562         return ret ? ret : count;
2563 }
2564
2565 static ssize_t trigger_test_error(struct ext4_attr *a,
2566                                   struct ext4_sb_info *sbi,
2567                                   const char *buf, size_t count)
2568 {
2569         int len = count;
2570
2571         if (!capable(CAP_SYS_ADMIN))
2572                 return -EPERM;
2573
2574         if (len && buf[len-1] == '\n')
2575                 len--;
2576
2577         if (len)
2578                 ext4_error(sbi->s_sb, "%.*s", len, buf);
2579         return count;
2580 }
2581
2582 static ssize_t sbi_deprecated_show(struct ext4_attr *a,
2583                                    struct ext4_sb_info *sbi, char *buf)
2584 {
2585         return snprintf(buf, PAGE_SIZE, "%d\n", a->u.deprecated_val);
2586 }
2587
2588 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2589 static struct ext4_attr ext4_attr_##_name = {                   \
2590         .attr = {.name = __stringify(_name), .mode = _mode },   \
2591         .show   = _show,                                        \
2592         .store  = _store,                                       \
2593         .u = {                                                  \
2594                 .offset = offsetof(struct ext4_sb_info, _elname),\
2595         },                                                      \
2596 }
2597
2598 #define EXT4_ATTR_OFFSET_ES(_name,_mode,_show,_store,_elname)           \
2599 static struct ext4_attr ext4_attr_##_name = {                           \
2600         .attr = {.name = __stringify(_name), .mode = _mode },           \
2601         .show   = _show,                                                \
2602         .store  = _store,                                               \
2603         .u = {                                                          \
2604                 .offset = offsetof(struct ext4_super_block, _elname),   \
2605         },                                                              \
2606 }
2607
2608 #define EXT4_ATTR(name, mode, show, store) \
2609 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2610
2611 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2612 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2613 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2614
2615 #define EXT4_RO_ATTR_ES_UI(name, elname)        \
2616         EXT4_ATTR_OFFSET_ES(name, 0444, es_ui_show, NULL, elname)
2617 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2618         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2619
2620 #define ATTR_LIST(name) &ext4_attr_##name.attr
2621 #define EXT4_DEPRECATED_ATTR(_name, _val)       \
2622 static struct ext4_attr ext4_attr_##_name = {                   \
2623         .attr = {.name = __stringify(_name), .mode = 0444 },    \
2624         .show   = sbi_deprecated_show,                          \
2625         .u = {                                                  \
2626                 .deprecated_val = _val,                         \
2627         },                                                      \
2628 }
2629
2630 EXT4_RO_ATTR(delayed_allocation_blocks);
2631 EXT4_RO_ATTR(session_write_kbytes);
2632 EXT4_RO_ATTR(lifetime_write_kbytes);
2633 EXT4_RW_ATTR(reserved_clusters);
2634 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2635                  inode_readahead_blks_store, s_inode_readahead_blks);
2636 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2637 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2638 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2639 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2640 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2641 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2642 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2643 EXT4_DEPRECATED_ATTR(max_writeback_mb_bump, 128);
2644 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
2645 EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error);
2646 EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
2647 EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst);
2648 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
2649 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
2650 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
2651 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
2652 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
2653 EXT4_RO_ATTR_ES_UI(first_error_time, s_first_error_time);
2654 EXT4_RO_ATTR_ES_UI(last_error_time, s_last_error_time);
2655
2656 static struct attribute *ext4_attrs[] = {
2657         ATTR_LIST(delayed_allocation_blocks),
2658         ATTR_LIST(session_write_kbytes),
2659         ATTR_LIST(lifetime_write_kbytes),
2660         ATTR_LIST(reserved_clusters),
2661         ATTR_LIST(inode_readahead_blks),
2662         ATTR_LIST(inode_goal),
2663         ATTR_LIST(mb_stats),
2664         ATTR_LIST(mb_max_to_scan),
2665         ATTR_LIST(mb_min_to_scan),
2666         ATTR_LIST(mb_order2_req),
2667         ATTR_LIST(mb_stream_req),
2668         ATTR_LIST(mb_group_prealloc),
2669         ATTR_LIST(max_writeback_mb_bump),
2670         ATTR_LIST(extent_max_zeroout_kb),
2671         ATTR_LIST(trigger_fs_error),
2672         ATTR_LIST(err_ratelimit_interval_ms),
2673         ATTR_LIST(err_ratelimit_burst),
2674         ATTR_LIST(warning_ratelimit_interval_ms),
2675         ATTR_LIST(warning_ratelimit_burst),
2676         ATTR_LIST(msg_ratelimit_interval_ms),
2677         ATTR_LIST(msg_ratelimit_burst),
2678         ATTR_LIST(errors_count),
2679         ATTR_LIST(first_error_time),
2680         ATTR_LIST(last_error_time),
2681         NULL,
2682 };
2683
2684 /* Features this copy of ext4 supports */
2685 EXT4_INFO_ATTR(lazy_itable_init);
2686 EXT4_INFO_ATTR(batched_discard);
2687 EXT4_INFO_ATTR(meta_bg_resize);
2688 EXT4_INFO_ATTR(encryption);
2689
2690 static struct attribute *ext4_feat_attrs[] = {
2691         ATTR_LIST(lazy_itable_init),
2692         ATTR_LIST(batched_discard),
2693         ATTR_LIST(meta_bg_resize),
2694         ATTR_LIST(encryption),
2695         NULL,
2696 };
2697
2698 static ssize_t ext4_attr_show(struct kobject *kobj,
2699                               struct attribute *attr, char *buf)
2700 {
2701         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2702                                                 s_kobj);
2703         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2704
2705         return a->show ? a->show(a, sbi, buf) : 0;
2706 }
2707
2708 static ssize_t ext4_attr_store(struct kobject *kobj,
2709                                struct attribute *attr,
2710                                const char *buf, size_t len)
2711 {
2712         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2713                                                 s_kobj);
2714         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2715
2716         return a->store ? a->store(a, sbi, buf, len) : 0;
2717 }
2718
2719 static void ext4_sb_release(struct kobject *kobj)
2720 {
2721         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2722                                                 s_kobj);
2723         complete(&sbi->s_kobj_unregister);
2724 }
2725
2726 static const struct sysfs_ops ext4_attr_ops = {
2727         .show   = ext4_attr_show,
2728         .store  = ext4_attr_store,
2729 };
2730
2731 static struct kobj_type ext4_ktype = {
2732         .default_attrs  = ext4_attrs,
2733         .sysfs_ops      = &ext4_attr_ops,
2734         .release        = ext4_sb_release,
2735 };
2736
2737 static void ext4_feat_release(struct kobject *kobj)
2738 {
2739         complete(&ext4_feat->f_kobj_unregister);
2740 }
2741
2742 static ssize_t ext4_feat_show(struct kobject *kobj,
2743                               struct attribute *attr, char *buf)
2744 {
2745         return snprintf(buf, PAGE_SIZE, "supported\n");
2746 }
2747
2748 /*
2749  * We can not use ext4_attr_show/store because it relies on the kobject
2750  * being embedded in the ext4_sb_info structure which is definitely not
2751  * true in this case.
2752  */
2753 static const struct sysfs_ops ext4_feat_ops = {
2754         .show   = ext4_feat_show,
2755         .store  = NULL,
2756 };
2757
2758 static struct kobj_type ext4_feat_ktype = {
2759         .default_attrs  = ext4_feat_attrs,
2760         .sysfs_ops      = &ext4_feat_ops,
2761         .release        = ext4_feat_release,
2762 };
2763
2764 /*
2765  * Check whether this filesystem can be mounted based on
2766  * the features present and the RDONLY/RDWR mount requested.
2767  * Returns 1 if this filesystem can be mounted as requested,
2768  * 0 if it cannot be.
2769  */
2770 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2771 {
2772         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2773                 ext4_msg(sb, KERN_ERR,
2774                         "Couldn't mount because of "
2775                         "unsupported optional features (%x)",
2776                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2777                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2778                 return 0;
2779         }
2780
2781         if (readonly)
2782                 return 1;
2783
2784         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_READONLY)) {
2785                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2786                 sb->s_flags |= MS_RDONLY;
2787                 return 1;
2788         }
2789
2790         /* Check that feature set is OK for a read-write mount */
2791         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2792                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2793                          "unsupported optional features (%x)",
2794                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2795                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2796                 return 0;
2797         }
2798         /*
2799          * Large file size enabled file system can only be mounted
2800          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2801          */
2802         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2803                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2804                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2805                                  "cannot be mounted RDWR without "
2806                                  "CONFIG_LBDAF");
2807                         return 0;
2808                 }
2809         }
2810         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2811             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2812                 ext4_msg(sb, KERN_ERR,
2813                          "Can't support bigalloc feature without "
2814                          "extents feature\n");
2815                 return 0;
2816         }
2817
2818 #ifndef CONFIG_QUOTA
2819         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
2820             !readonly) {
2821                 ext4_msg(sb, KERN_ERR,
2822                          "Filesystem with quota feature cannot be mounted RDWR "
2823                          "without CONFIG_QUOTA");
2824                 return 0;
2825         }
2826 #endif  /* CONFIG_QUOTA */
2827         return 1;
2828 }
2829
2830 /*
2831  * This function is called once a day if we have errors logged
2832  * on the file system
2833  */
2834 static void print_daily_error_info(unsigned long arg)
2835 {
2836         struct super_block *sb = (struct super_block *) arg;
2837         struct ext4_sb_info *sbi;
2838         struct ext4_super_block *es;
2839
2840         sbi = EXT4_SB(sb);
2841         es = sbi->s_es;
2842
2843         if (es->s_error_count)
2844                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2845                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2846                          le32_to_cpu(es->s_error_count));
2847         if (es->s_first_error_time) {
2848                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2849                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2850                        (int) sizeof(es->s_first_error_func),
2851                        es->s_first_error_func,
2852                        le32_to_cpu(es->s_first_error_line));
2853                 if (es->s_first_error_ino)
2854                         printk(": inode %u",
2855                                le32_to_cpu(es->s_first_error_ino));
2856                 if (es->s_first_error_block)
2857                         printk(": block %llu", (unsigned long long)
2858                                le64_to_cpu(es->s_first_error_block));
2859                 printk("\n");
2860         }
2861         if (es->s_last_error_time) {
2862                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2863                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2864                        (int) sizeof(es->s_last_error_func),
2865                        es->s_last_error_func,
2866                        le32_to_cpu(es->s_last_error_line));
2867                 if (es->s_last_error_ino)
2868                         printk(": inode %u",
2869                                le32_to_cpu(es->s_last_error_ino));
2870                 if (es->s_last_error_block)
2871                         printk(": block %llu", (unsigned long long)
2872                                le64_to_cpu(es->s_last_error_block));
2873                 printk("\n");
2874         }
2875         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2876 }
2877
2878 /* Find next suitable group and run ext4_init_inode_table */
2879 static int ext4_run_li_request(struct ext4_li_request *elr)
2880 {
2881         struct ext4_group_desc *gdp = NULL;
2882         ext4_group_t group, ngroups;
2883         struct super_block *sb;
2884         unsigned long timeout = 0;
2885         int ret = 0;
2886
2887         sb = elr->lr_super;
2888         ngroups = EXT4_SB(sb)->s_groups_count;
2889
2890         sb_start_write(sb);
2891         for (group = elr->lr_next_group; group < ngroups; group++) {
2892                 gdp = ext4_get_group_desc(sb, group, NULL);
2893                 if (!gdp) {
2894                         ret = 1;
2895                         break;
2896                 }
2897
2898                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2899                         break;
2900         }
2901
2902         if (group >= ngroups)
2903                 ret = 1;
2904
2905         if (!ret) {
2906                 timeout = jiffies;
2907                 ret = ext4_init_inode_table(sb, group,
2908                                             elr->lr_timeout ? 0 : 1);
2909                 if (elr->lr_timeout == 0) {
2910                         timeout = (jiffies - timeout) *
2911                                   elr->lr_sbi->s_li_wait_mult;
2912                         elr->lr_timeout = timeout;
2913                 }
2914                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2915                 elr->lr_next_group = group + 1;
2916         }
2917         sb_end_write(sb);
2918
2919         return ret;
2920 }
2921
2922 /*
2923  * Remove lr_request from the list_request and free the
2924  * request structure. Should be called with li_list_mtx held
2925  */
2926 static void ext4_remove_li_request(struct ext4_li_request *elr)
2927 {
2928         struct ext4_sb_info *sbi;
2929
2930         if (!elr)
2931                 return;
2932
2933         sbi = elr->lr_sbi;
2934
2935         list_del(&elr->lr_request);
2936         sbi->s_li_request = NULL;
2937         kfree(elr);
2938 }
2939
2940 static void ext4_unregister_li_request(struct super_block *sb)
2941 {
2942         mutex_lock(&ext4_li_mtx);
2943         if (!ext4_li_info) {
2944                 mutex_unlock(&ext4_li_mtx);
2945                 return;
2946         }
2947
2948         mutex_lock(&ext4_li_info->li_list_mtx);
2949         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2950         mutex_unlock(&ext4_li_info->li_list_mtx);
2951         mutex_unlock(&ext4_li_mtx);
2952 }
2953
2954 static struct task_struct *ext4_lazyinit_task;
2955
2956 /*
2957  * This is the function where ext4lazyinit thread lives. It walks
2958  * through the request list searching for next scheduled filesystem.
2959  * When such a fs is found, run the lazy initialization request
2960  * (ext4_rn_li_request) and keep track of the time spend in this
2961  * function. Based on that time we compute next schedule time of
2962  * the request. When walking through the list is complete, compute
2963  * next waking time and put itself into sleep.
2964  */
2965 static int ext4_lazyinit_thread(void *arg)
2966 {
2967         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2968         struct list_head *pos, *n;
2969         struct ext4_li_request *elr;
2970         unsigned long next_wakeup, cur;
2971
2972         BUG_ON(NULL == eli);
2973
2974 cont_thread:
2975         while (true) {
2976                 next_wakeup = MAX_JIFFY_OFFSET;
2977
2978                 mutex_lock(&eli->li_list_mtx);
2979                 if (list_empty(&eli->li_request_list)) {
2980                         mutex_unlock(&eli->li_list_mtx);
2981                         goto exit_thread;
2982                 }
2983
2984                 list_for_each_safe(pos, n, &eli->li_request_list) {
2985                         elr = list_entry(pos, struct ext4_li_request,
2986                                          lr_request);
2987
2988                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2989                                 if (ext4_run_li_request(elr) != 0) {
2990                                         /* error, remove the lazy_init job */
2991                                         ext4_remove_li_request(elr);
2992                                         continue;
2993                                 }
2994                         }
2995
2996                         if (time_before(elr->lr_next_sched, next_wakeup))
2997                                 next_wakeup = elr->lr_next_sched;
2998                 }
2999                 mutex_unlock(&eli->li_list_mtx);
3000
3001                 try_to_freeze();
3002
3003                 cur = jiffies;
3004                 if ((time_after_eq(cur, next_wakeup)) ||
3005                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3006                         cond_resched();
3007                         continue;
3008                 }
3009
3010                 schedule_timeout_interruptible(next_wakeup - cur);
3011
3012                 if (kthread_should_stop()) {
3013                         ext4_clear_request_list();
3014                         goto exit_thread;
3015                 }
3016         }
3017
3018 exit_thread:
3019         /*
3020          * It looks like the request list is empty, but we need
3021          * to check it under the li_list_mtx lock, to prevent any
3022          * additions into it, and of course we should lock ext4_li_mtx
3023          * to atomically free the list and ext4_li_info, because at
3024          * this point another ext4 filesystem could be registering
3025          * new one.
3026          */
3027         mutex_lock(&ext4_li_mtx);
3028         mutex_lock(&eli->li_list_mtx);
3029         if (!list_empty(&eli->li_request_list)) {
3030                 mutex_unlock(&eli->li_list_mtx);
3031                 mutex_unlock(&ext4_li_mtx);
3032                 goto cont_thread;
3033         }
3034         mutex_unlock(&eli->li_list_mtx);
3035         kfree(ext4_li_info);
3036         ext4_li_info = NULL;
3037         mutex_unlock(&ext4_li_mtx);
3038
3039         return 0;
3040 }
3041
3042 static void ext4_clear_request_list(void)
3043 {
3044         struct list_head *pos, *n;
3045         struct ext4_li_request *elr;
3046
3047         mutex_lock(&ext4_li_info->li_list_mtx);
3048         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3049                 elr = list_entry(pos, struct ext4_li_request,
3050                                  lr_request);
3051                 ext4_remove_li_request(elr);
3052         }
3053         mutex_unlock(&ext4_li_info->li_list_mtx);
3054 }
3055
3056 static int ext4_run_lazyinit_thread(void)
3057 {
3058         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3059                                          ext4_li_info, "ext4lazyinit");
3060         if (IS_ERR(ext4_lazyinit_task)) {
3061                 int err = PTR_ERR(ext4_lazyinit_task);
3062                 ext4_clear_request_list();
3063                 kfree(ext4_li_info);
3064                 ext4_li_info = NULL;
3065                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3066                                  "initialization thread\n",
3067                                  err);
3068                 return err;
3069         }
3070         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3071         return 0;
3072 }
3073
3074 /*
3075  * Check whether it make sense to run itable init. thread or not.
3076  * If there is at least one uninitialized inode table, return
3077  * corresponding group number, else the loop goes through all
3078  * groups and return total number of groups.
3079  */
3080 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3081 {
3082         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3083         struct ext4_group_desc *gdp = NULL;
3084
3085         for (group = 0; group < ngroups; group++) {
3086                 gdp = ext4_get_group_desc(sb, group, NULL);
3087                 if (!gdp)
3088                         continue;
3089
3090                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3091                         break;
3092         }
3093
3094         return group;
3095 }
3096
3097 static int ext4_li_info_new(void)
3098 {
3099         struct ext4_lazy_init *eli = NULL;
3100
3101         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3102         if (!eli)
3103                 return -ENOMEM;
3104
3105         INIT_LIST_HEAD(&eli->li_request_list);
3106         mutex_init(&eli->li_list_mtx);
3107
3108         eli->li_state |= EXT4_LAZYINIT_QUIT;
3109
3110         ext4_li_info = eli;
3111
3112         return 0;
3113 }
3114
3115 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3116                                             ext4_group_t start)
3117 {
3118         struct ext4_sb_info *sbi = EXT4_SB(sb);
3119         struct ext4_li_request *elr;
3120
3121         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3122         if (!elr)
3123                 return NULL;
3124
3125         elr->lr_super = sb;
3126         elr->lr_sbi = sbi;
3127         elr->lr_next_group = start;
3128
3129         /*
3130          * Randomize first schedule time of the request to
3131          * spread the inode table initialization requests
3132          * better.
3133          */
3134         elr->lr_next_sched = jiffies + (prandom_u32() %
3135                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3136         return elr;
3137 }
3138
3139 int ext4_register_li_request(struct super_block *sb,
3140                              ext4_group_t first_not_zeroed)
3141 {
3142         struct ext4_sb_info *sbi = EXT4_SB(sb);
3143         struct ext4_li_request *elr = NULL;
3144         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3145         int ret = 0;
3146
3147         mutex_lock(&ext4_li_mtx);
3148         if (sbi->s_li_request != NULL) {
3149                 /*
3150                  * Reset timeout so it can be computed again, because
3151                  * s_li_wait_mult might have changed.
3152                  */
3153                 sbi->s_li_request->lr_timeout = 0;
3154                 goto out;
3155         }
3156
3157         if (first_not_zeroed == ngroups ||
3158             (sb->s_flags & MS_RDONLY) ||
3159             !test_opt(sb, INIT_INODE_TABLE))
3160                 goto out;
3161
3162         elr = ext4_li_request_new(sb, first_not_zeroed);
3163         if (!elr) {
3164                 ret = -ENOMEM;
3165                 goto out;
3166         }
3167
3168         if (NULL == ext4_li_info) {
3169                 ret = ext4_li_info_new();
3170                 if (ret)
3171                         goto out;
3172         }
3173
3174         mutex_lock(&ext4_li_info->li_list_mtx);
3175         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3176         mutex_unlock(&ext4_li_info->li_list_mtx);
3177
3178         sbi->s_li_request = elr;
3179         /*
3180          * set elr to NULL here since it has been inserted to
3181          * the request_list and the removal and free of it is
3182          * handled by ext4_clear_request_list from now on.
3183          */
3184         elr = NULL;
3185
3186         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3187                 ret = ext4_run_lazyinit_thread();
3188                 if (ret)
3189                         goto out;
3190         }
3191 out:
3192         mutex_unlock(&ext4_li_mtx);
3193         if (ret)
3194                 kfree(elr);
3195         return ret;
3196 }
3197
3198 /*
3199  * We do not need to lock anything since this is called on
3200  * module unload.
3201  */
3202 static void ext4_destroy_lazyinit_thread(void)
3203 {
3204         /*
3205          * If thread exited earlier
3206          * there's nothing to be done.
3207          */
3208         if (!ext4_li_info || !ext4_lazyinit_task)
3209                 return;
3210
3211         kthread_stop(ext4_lazyinit_task);
3212 }
3213
3214 static int set_journal_csum_feature_set(struct super_block *sb)
3215 {
3216         int ret = 1;
3217         int compat, incompat;
3218         struct ext4_sb_info *sbi = EXT4_SB(sb);
3219
3220         if (ext4_has_metadata_csum(sb)) {
3221                 /* journal checksum v3 */
3222                 compat = 0;
3223                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3224         } else {
3225                 /* journal checksum v1 */
3226                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3227                 incompat = 0;
3228         }
3229
3230         jbd2_journal_clear_features(sbi->s_journal,
3231                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3232                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3233                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3234         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3235                 ret = jbd2_journal_set_features(sbi->s_journal,
3236                                 compat, 0,
3237                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3238                                 incompat);
3239         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3240                 ret = jbd2_journal_set_features(sbi->s_journal,
3241                                 compat, 0,
3242                                 incompat);
3243                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3244                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3245         } else {
3246                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3247                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3248         }
3249
3250         return ret;
3251 }
3252
3253 /*
3254  * Note: calculating the overhead so we can be compatible with
3255  * historical BSD practice is quite difficult in the face of
3256  * clusters/bigalloc.  This is because multiple metadata blocks from
3257  * different block group can end up in the same allocation cluster.
3258  * Calculating the exact overhead in the face of clustered allocation
3259  * requires either O(all block bitmaps) in memory or O(number of block
3260  * groups**2) in time.  We will still calculate the superblock for
3261  * older file systems --- and if we come across with a bigalloc file
3262  * system with zero in s_overhead_clusters the estimate will be close to
3263  * correct especially for very large cluster sizes --- but for newer
3264  * file systems, it's better to calculate this figure once at mkfs
3265  * time, and store it in the superblock.  If the superblock value is
3266  * present (even for non-bigalloc file systems), we will use it.
3267  */
3268 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3269                           char *buf)
3270 {
3271         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3272         struct ext4_group_desc  *gdp;
3273         ext4_fsblk_t            first_block, last_block, b;
3274         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3275         int                     s, j, count = 0;
3276
3277         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC))
3278                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3279                         sbi->s_itb_per_group + 2);
3280
3281         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3282                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3283         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3284         for (i = 0; i < ngroups; i++) {
3285                 gdp = ext4_get_group_desc(sb, i, NULL);
3286                 b = ext4_block_bitmap(sb, gdp);
3287                 if (b >= first_block && b <= last_block) {
3288                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3289                         count++;
3290                 }
3291                 b = ext4_inode_bitmap(sb, gdp);
3292                 if (b >= first_block && b <= last_block) {
3293                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3294                         count++;
3295                 }
3296                 b = ext4_inode_table(sb, gdp);
3297                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3298                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3299                                 int c = EXT4_B2C(sbi, b - first_block);
3300                                 ext4_set_bit(c, buf);
3301                                 count++;
3302                         }
3303                 if (i != grp)
3304                         continue;
3305                 s = 0;
3306                 if (ext4_bg_has_super(sb, grp)) {
3307                         ext4_set_bit(s++, buf);
3308                         count++;
3309                 }
3310                 for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3311                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3312                         count++;
3313                 }
3314         }
3315         if (!count)
3316                 return 0;
3317         return EXT4_CLUSTERS_PER_GROUP(sb) -
3318                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3319 }
3320
3321 /*
3322  * Compute the overhead and stash it in sbi->s_overhead
3323  */
3324 int ext4_calculate_overhead(struct super_block *sb)
3325 {
3326         struct ext4_sb_info *sbi = EXT4_SB(sb);
3327         struct ext4_super_block *es = sbi->s_es;
3328         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3329         ext4_fsblk_t overhead = 0;
3330         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3331
3332         if (!buf)
3333                 return -ENOMEM;
3334
3335         /*
3336          * Compute the overhead (FS structures).  This is constant
3337          * for a given filesystem unless the number of block groups
3338          * changes so we cache the previous value until it does.
3339          */
3340
3341         /*
3342          * All of the blocks before first_data_block are overhead
3343          */
3344         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3345
3346         /*
3347          * Add the overhead found in each block group
3348          */
3349         for (i = 0; i < ngroups; i++) {
3350                 int blks;
3351
3352                 blks = count_overhead(sb, i, buf);
3353                 overhead += blks;
3354                 if (blks)
3355                         memset(buf, 0, PAGE_SIZE);
3356                 cond_resched();
3357         }
3358         /* Add the internal journal blocks as well */
3359         if (sbi->s_journal && !sbi->journal_bdev)
3360                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3361
3362         sbi->s_overhead = overhead;
3363         smp_wmb();
3364         free_page((unsigned long) buf);
3365         return 0;
3366 }
3367
3368
3369 static ext4_fsblk_t ext4_calculate_resv_clusters(struct super_block *sb)
3370 {
3371         ext4_fsblk_t resv_clusters;
3372
3373         /*
3374          * There's no need to reserve anything when we aren't using extents.
3375          * The space estimates are exact, there are no unwritten extents,
3376          * hole punching doesn't need new metadata... This is needed especially
3377          * to keep ext2/3 backward compatibility.
3378          */
3379         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
3380                 return 0;
3381         /*
3382          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3383          * This should cover the situations where we can not afford to run
3384          * out of space like for example punch hole, or converting
3385          * unwritten extents in delalloc path. In most cases such
3386          * allocation would require 1, or 2 blocks, higher numbers are
3387          * very rare.
3388          */
3389         resv_clusters = ext4_blocks_count(EXT4_SB(sb)->s_es) >>
3390                         EXT4_SB(sb)->s_cluster_bits;
3391
3392         do_div(resv_clusters, 50);
3393         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3394
3395         return resv_clusters;
3396 }
3397
3398
3399 static int ext4_reserve_clusters(struct ext4_sb_info *sbi, ext4_fsblk_t count)
3400 {
3401         ext4_fsblk_t clusters = ext4_blocks_count(sbi->s_es) >>
3402                                 sbi->s_cluster_bits;
3403
3404         if (count >= clusters)
3405                 return -EINVAL;
3406
3407         atomic64_set(&sbi->s_resv_clusters, count);
3408         return 0;
3409 }
3410
3411 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3412 {
3413         char *orig_data = kstrdup(data, GFP_KERNEL);
3414         struct buffer_head *bh;
3415         struct ext4_super_block *es = NULL;
3416         struct ext4_sb_info *sbi;
3417         ext4_fsblk_t block;
3418         ext4_fsblk_t sb_block = get_sb_block(&data);
3419         ext4_fsblk_t logical_sb_block;
3420         unsigned long offset = 0;
3421         unsigned long journal_devnum = 0;
3422         unsigned long def_mount_opts;
3423         struct inode *root;
3424         char *cp;
3425         const char *descr;
3426         int ret = -ENOMEM;
3427         int blocksize, clustersize;
3428         unsigned int db_count;
3429         unsigned int i;
3430         int needs_recovery, has_huge_files, has_bigalloc;
3431         __u64 blocks_count;
3432         int err = 0;
3433         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3434         ext4_group_t first_not_zeroed;
3435
3436         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3437         if (!sbi)
3438                 goto out_free_orig;
3439
3440         sbi->s_blockgroup_lock =
3441                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3442         if (!sbi->s_blockgroup_lock) {
3443                 kfree(sbi);
3444                 goto out_free_orig;
3445         }
3446         sb->s_fs_info = sbi;
3447         sbi->s_sb = sb;
3448         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3449         sbi->s_sb_block = sb_block;
3450         if (sb->s_bdev->bd_part)
3451                 sbi->s_sectors_written_start =
3452                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3453 #ifdef CONFIG_EXT4_FS_ENCRYPTION
3454         /* Modes of operations for file and directory encryption. */
3455         sbi->s_file_encryption_mode = EXT4_ENCRYPTION_MODE_AES_256_XTS;
3456         sbi->s_dir_encryption_mode = EXT4_ENCRYPTION_MODE_INVALID;
3457 #endif
3458
3459         /* Cleanup superblock name */
3460         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3461                 *cp = '!';
3462
3463         /* -EINVAL is default */
3464         ret = -EINVAL;
3465         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3466         if (!blocksize) {
3467                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3468                 goto out_fail;
3469         }
3470
3471         /*
3472          * The ext4 superblock will not be buffer aligned for other than 1kB
3473          * block sizes.  We need to calculate the offset from buffer start.
3474          */
3475         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3476                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3477                 offset = do_div(logical_sb_block, blocksize);
3478         } else {
3479                 logical_sb_block = sb_block;
3480         }
3481
3482         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3483                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3484                 goto out_fail;
3485         }
3486         /*
3487          * Note: s_es must be initialized as soon as possible because
3488          *       some ext4 macro-instructions depend on its value
3489          */
3490         es = (struct ext4_super_block *) (bh->b_data + offset);
3491         sbi->s_es = es;
3492         sb->s_magic = le16_to_cpu(es->s_magic);
3493         if (sb->s_magic != EXT4_SUPER_MAGIC)
3494                 goto cantfind_ext4;
3495         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3496
3497         /* Warn if metadata_csum and gdt_csum are both set. */
3498         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3499                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
3500             EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
3501                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3502                              "redundant flags; please run fsck.");
3503
3504         /* Check for a known checksum algorithm */
3505         if (!ext4_verify_csum_type(sb, es)) {
3506                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3507                          "unknown checksum algorithm.");
3508                 silent = 1;
3509                 goto cantfind_ext4;
3510         }
3511
3512         /* Load the checksum driver */
3513         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3514                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3515                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3516                 if (IS_ERR(sbi->s_chksum_driver)) {
3517                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3518                         ret = PTR_ERR(sbi->s_chksum_driver);
3519                         sbi->s_chksum_driver = NULL;
3520                         goto failed_mount;
3521                 }
3522         }
3523
3524         /* Check superblock checksum */
3525         if (!ext4_superblock_csum_verify(sb, es)) {
3526                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3527                          "invalid superblock checksum.  Run e2fsck?");
3528                 silent = 1;
3529                 goto cantfind_ext4;
3530         }
3531
3532         /* Precompute checksum seed for all metadata */
3533         if (ext4_has_metadata_csum(sb))
3534                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3535                                                sizeof(es->s_uuid));
3536
3537         /* Set defaults before we parse the mount options */
3538         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3539         set_opt(sb, INIT_INODE_TABLE);
3540         if (def_mount_opts & EXT4_DEFM_DEBUG)
3541                 set_opt(sb, DEBUG);
3542         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3543                 set_opt(sb, GRPID);
3544         if (def_mount_opts & EXT4_DEFM_UID16)
3545                 set_opt(sb, NO_UID32);
3546         /* xattr user namespace & acls are now defaulted on */
3547         set_opt(sb, XATTR_USER);
3548 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3549         set_opt(sb, POSIX_ACL);
3550 #endif
3551         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3552         if (ext4_has_metadata_csum(sb))
3553                 set_opt(sb, JOURNAL_CHECKSUM);
3554
3555         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3556                 set_opt(sb, JOURNAL_DATA);
3557         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3558                 set_opt(sb, ORDERED_DATA);
3559         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3560                 set_opt(sb, WRITEBACK_DATA);
3561
3562         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3563                 set_opt(sb, ERRORS_PANIC);
3564         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3565                 set_opt(sb, ERRORS_CONT);
3566         else
3567                 set_opt(sb, ERRORS_RO);
3568         /* block_validity enabled by default; disable with noblock_validity */
3569         set_opt(sb, BLOCK_VALIDITY);
3570         if (def_mount_opts & EXT4_DEFM_DISCARD)
3571                 set_opt(sb, DISCARD);
3572
3573         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3574         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3575         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3576         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3577         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3578
3579         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3580                 set_opt(sb, BARRIER);
3581
3582         /*
3583          * enable delayed allocation by default
3584          * Use -o nodelalloc to turn it off
3585          */
3586         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3587             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3588                 set_opt(sb, DELALLOC);
3589
3590         /*
3591          * set default s_li_wait_mult for lazyinit, for the case there is
3592          * no mount option specified.
3593          */
3594         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3595
3596         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3597                            &journal_devnum, &journal_ioprio, 0)) {
3598                 ext4_msg(sb, KERN_WARNING,
3599                          "failed to parse options in superblock: %s",
3600                          sbi->s_es->s_mount_opts);
3601         }
3602         sbi->s_def_mount_opt = sbi->s_mount_opt;
3603         if (!parse_options((char *) data, sb, &journal_devnum,
3604                            &journal_ioprio, 0))
3605                 goto failed_mount;
3606
3607         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3608                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3609                             "with data=journal disables delayed "
3610                             "allocation and O_DIRECT support!\n");
3611                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3612                         ext4_msg(sb, KERN_ERR, "can't mount with "
3613                                  "both data=journal and delalloc");
3614                         goto failed_mount;
3615                 }
3616                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3617                         ext4_msg(sb, KERN_ERR, "can't mount with "
3618                                  "both data=journal and dioread_nolock");
3619                         goto failed_mount;
3620                 }
3621                 if (test_opt(sb, DAX)) {
3622                         ext4_msg(sb, KERN_ERR, "can't mount with "
3623                                  "both data=journal and dax");
3624                         goto failed_mount;
3625                 }
3626                 if (test_opt(sb, DELALLOC))
3627                         clear_opt(sb, DELALLOC);
3628         }
3629
3630         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3631                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3632
3633         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3634             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3635              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3636              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3637                 ext4_msg(sb, KERN_WARNING,
3638                        "feature flags set on rev 0 fs, "
3639                        "running e2fsck is recommended");
3640
3641         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3642                 set_opt2(sb, HURD_COMPAT);
3643                 if (EXT4_HAS_INCOMPAT_FEATURE(sb,
3644                                               EXT4_FEATURE_INCOMPAT_64BIT)) {
3645                         ext4_msg(sb, KERN_ERR,
3646                                  "The Hurd can't support 64-bit file systems");
3647                         goto failed_mount;
3648                 }
3649         }
3650
3651         if (IS_EXT2_SB(sb)) {
3652                 if (ext2_feature_set_ok(sb))
3653                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3654                                  "using the ext4 subsystem");
3655                 else {
3656                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3657                                  "to feature incompatibilities");
3658                         goto failed_mount;
3659                 }
3660         }
3661
3662         if (IS_EXT3_SB(sb)) {
3663                 if (ext3_feature_set_ok(sb))
3664                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3665                                  "using the ext4 subsystem");
3666                 else {
3667                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3668                                  "to feature incompatibilities");
3669                         goto failed_mount;
3670                 }
3671         }
3672
3673         /*
3674          * Check feature flags regardless of the revision level, since we
3675          * previously didn't change the revision level when setting the flags,
3676          * so there is a chance incompat flags are set on a rev 0 filesystem.
3677          */
3678         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3679                 goto failed_mount;
3680
3681         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3682         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3683             blocksize > EXT4_MAX_BLOCK_SIZE) {
3684                 ext4_msg(sb, KERN_ERR,
3685                        "Unsupported filesystem blocksize %d", blocksize);
3686                 goto failed_mount;
3687         }
3688
3689         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3690                 if (blocksize != PAGE_SIZE) {
3691                         ext4_msg(sb, KERN_ERR,
3692                                         "error: unsupported blocksize for dax");
3693                         goto failed_mount;
3694                 }
3695                 if (!sb->s_bdev->bd_disk->fops->direct_access) {
3696                         ext4_msg(sb, KERN_ERR,
3697                                         "error: device does not support dax");
3698                         goto failed_mount;
3699                 }
3700         }
3701
3702         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT) &&
3703             es->s_encryption_level) {
3704                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3705                          es->s_encryption_level);
3706                 goto failed_mount;
3707         }
3708
3709         if (sb->s_blocksize != blocksize) {
3710                 /* Validate the filesystem blocksize */
3711                 if (!sb_set_blocksize(sb, blocksize)) {
3712                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3713                                         blocksize);
3714                         goto failed_mount;
3715                 }
3716
3717                 brelse(bh);
3718                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3719                 offset = do_div(logical_sb_block, blocksize);
3720                 bh = sb_bread_unmovable(sb, logical_sb_block);
3721                 if (!bh) {
3722                         ext4_msg(sb, KERN_ERR,
3723                                "Can't read superblock on 2nd try");
3724                         goto failed_mount;
3725                 }
3726                 es = (struct ext4_super_block *)(bh->b_data + offset);
3727                 sbi->s_es = es;
3728                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3729                         ext4_msg(sb, KERN_ERR,
3730                                "Magic mismatch, very weird!");
3731                         goto failed_mount;
3732                 }
3733         }
3734
3735         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3736                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3737         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3738                                                       has_huge_files);
3739         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3740
3741         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3742                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3743                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3744         } else {
3745                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3746                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3747                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3748                     (!is_power_of_2(sbi->s_inode_size)) ||
3749                     (sbi->s_inode_size > blocksize)) {
3750                         ext4_msg(sb, KERN_ERR,
3751                                "unsupported inode size: %d",
3752                                sbi->s_inode_size);
3753                         goto failed_mount;
3754                 }
3755                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3756                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3757         }
3758
3759         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3760         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3761                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3762                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3763                     !is_power_of_2(sbi->s_desc_size)) {
3764                         ext4_msg(sb, KERN_ERR,
3765                                "unsupported descriptor size %lu",
3766                                sbi->s_desc_size);
3767                         goto failed_mount;
3768                 }
3769         } else
3770                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3771
3772         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3773         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3774         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3775                 goto cantfind_ext4;
3776
3777         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3778         if (sbi->s_inodes_per_block == 0)
3779                 goto cantfind_ext4;
3780         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3781                                         sbi->s_inodes_per_block;
3782         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3783         sbi->s_sbh = bh;
3784         sbi->s_mount_state = le16_to_cpu(es->s_state);
3785         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3786         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3787
3788         for (i = 0; i < 4; i++)
3789                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3790         sbi->s_def_hash_version = es->s_def_hash_version;
3791         if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX)) {
3792                 i = le32_to_cpu(es->s_flags);
3793                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
3794                         sbi->s_hash_unsigned = 3;
3795                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3796 #ifdef __CHAR_UNSIGNED__
3797                         if (!(sb->s_flags & MS_RDONLY))
3798                                 es->s_flags |=
3799                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3800                         sbi->s_hash_unsigned = 3;
3801 #else
3802                         if (!(sb->s_flags & MS_RDONLY))
3803                                 es->s_flags |=
3804                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3805 #endif
3806                 }
3807         }
3808
3809         /* Handle clustersize */
3810         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3811         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3812                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3813         if (has_bigalloc) {
3814                 if (clustersize < blocksize) {
3815                         ext4_msg(sb, KERN_ERR,
3816                                  "cluster size (%d) smaller than "
3817                                  "block size (%d)", clustersize, blocksize);
3818                         goto failed_mount;
3819                 }
3820                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3821                         le32_to_cpu(es->s_log_block_size);
3822                 sbi->s_clusters_per_group =
3823                         le32_to_cpu(es->s_clusters_per_group);
3824                 if (sbi->s_clusters_per_group > blocksize * 8) {
3825                         ext4_msg(sb, KERN_ERR,
3826                                  "#clusters per group too big: %lu",
3827                                  sbi->s_clusters_per_group);
3828                         goto failed_mount;
3829                 }
3830                 if (sbi->s_blocks_per_group !=
3831                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3832                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3833                                  "clusters per group (%lu) inconsistent",
3834                                  sbi->s_blocks_per_group,
3835                                  sbi->s_clusters_per_group);
3836                         goto failed_mount;
3837                 }
3838         } else {
3839                 if (clustersize != blocksize) {
3840                         ext4_warning(sb, "fragment/cluster size (%d) != "
3841                                      "block size (%d)", clustersize,
3842                                      blocksize);
3843                         clustersize = blocksize;
3844                 }
3845                 if (sbi->s_blocks_per_group > blocksize * 8) {
3846                         ext4_msg(sb, KERN_ERR,
3847                                  "#blocks per group too big: %lu",
3848                                  sbi->s_blocks_per_group);
3849                         goto failed_mount;
3850                 }
3851                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3852                 sbi->s_cluster_bits = 0;
3853         }
3854         sbi->s_cluster_ratio = clustersize / blocksize;
3855
3856         if (sbi->s_inodes_per_group > blocksize * 8) {
3857                 ext4_msg(sb, KERN_ERR,
3858                        "#inodes per group too big: %lu",
3859                        sbi->s_inodes_per_group);
3860                 goto failed_mount;
3861         }
3862
3863         /* Do we have standard group size of clustersize * 8 blocks ? */
3864         if (sbi->s_blocks_per_group == clustersize << 3)
3865                 set_opt2(sb, STD_GROUP_SIZE);
3866
3867         /*
3868          * Test whether we have more sectors than will fit in sector_t,
3869          * and whether the max offset is addressable by the page cache.
3870          */
3871         err = generic_check_addressable(sb->s_blocksize_bits,
3872                                         ext4_blocks_count(es));
3873         if (err) {
3874                 ext4_msg(sb, KERN_ERR, "filesystem"
3875                          " too large to mount safely on this system");
3876                 if (sizeof(sector_t) < 8)
3877                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3878                 goto failed_mount;
3879         }
3880
3881         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3882                 goto cantfind_ext4;
3883
3884         /* check blocks count against device size */
3885         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3886         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3887                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3888                        "exceeds size of device (%llu blocks)",
3889                        ext4_blocks_count(es), blocks_count);
3890                 goto failed_mount;
3891         }
3892
3893         /*
3894          * It makes no sense for the first data block to be beyond the end
3895          * of the filesystem.
3896          */
3897         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3898                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3899                          "block %u is beyond end of filesystem (%llu)",
3900                          le32_to_cpu(es->s_first_data_block),
3901                          ext4_blocks_count(es));
3902                 goto failed_mount;
3903         }
3904         blocks_count = (ext4_blocks_count(es) -
3905                         le32_to_cpu(es->s_first_data_block) +
3906                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3907         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3908         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3909                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3910                        "(block count %llu, first data block %u, "
3911                        "blocks per group %lu)", sbi->s_groups_count,
3912                        ext4_blocks_count(es),
3913                        le32_to_cpu(es->s_first_data_block),
3914                        EXT4_BLOCKS_PER_GROUP(sb));
3915                 goto failed_mount;
3916         }
3917         sbi->s_groups_count = blocks_count;
3918         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3919                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3920         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3921                    EXT4_DESC_PER_BLOCK(sb);
3922         sbi->s_group_desc = ext4_kvmalloc(db_count *
3923                                           sizeof(struct buffer_head *),
3924                                           GFP_KERNEL);
3925         if (sbi->s_group_desc == NULL) {
3926                 ext4_msg(sb, KERN_ERR, "not enough memory");
3927                 ret = -ENOMEM;
3928                 goto failed_mount;
3929         }
3930
3931         if (ext4_proc_root)
3932                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3933
3934         if (sbi->s_proc)
3935                 proc_create_data("options", S_IRUGO, sbi->s_proc,
3936                                  &ext4_seq_options_fops, sb);
3937
3938         bgl_lock_init(sbi->s_blockgroup_lock);
3939
3940         for (i = 0; i < db_count; i++) {
3941                 block = descriptor_loc(sb, logical_sb_block, i);
3942                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
3943                 if (!sbi->s_group_desc[i]) {
3944                         ext4_msg(sb, KERN_ERR,
3945                                "can't read group descriptor %d", i);
3946                         db_count = i;
3947                         goto failed_mount2;
3948                 }
3949         }
3950         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3951                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3952                 goto failed_mount2;
3953         }
3954
3955         sbi->s_gdb_count = db_count;
3956         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3957         spin_lock_init(&sbi->s_next_gen_lock);
3958
3959         setup_timer(&sbi->s_err_report, print_daily_error_info,
3960                 (unsigned long) sb);
3961
3962         /* Register extent status tree shrinker */
3963         if (ext4_es_register_shrinker(sbi))
3964                 goto failed_mount3;
3965
3966         sbi->s_stripe = ext4_get_stripe_size(sbi);
3967         sbi->s_extent_max_zeroout_kb = 32;
3968
3969         /*
3970          * set up enough so that it can read an inode
3971          */
3972         sb->s_op = &ext4_sops;
3973         sb->s_export_op = &ext4_export_ops;
3974         sb->s_xattr = ext4_xattr_handlers;
3975 #ifdef CONFIG_QUOTA
3976         sb->dq_op = &ext4_quota_operations;
3977         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
3978                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
3979         else
3980                 sb->s_qcop = &ext4_qctl_operations;
3981         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
3982 #endif
3983         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3984
3985         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3986         mutex_init(&sbi->s_orphan_lock);
3987
3988         sb->s_root = NULL;
3989
3990         needs_recovery = (es->s_last_orphan != 0 ||
3991                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3992                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3993
3994         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3995             !(sb->s_flags & MS_RDONLY))
3996                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3997                         goto failed_mount3a;
3998
3999         /*
4000          * The first inode we look at is the journal inode.  Don't try
4001          * root first: it may be modified in the journal!
4002          */
4003         if (!test_opt(sb, NOLOAD) &&
4004             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4005                 if (ext4_load_journal(sb, es, journal_devnum))
4006                         goto failed_mount3a;
4007         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
4008               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4009                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4010                        "suppressed and not mounted read-only");
4011                 goto failed_mount_wq;
4012         } else {
4013                 clear_opt(sb, DATA_FLAGS);
4014                 sbi->s_journal = NULL;
4015                 needs_recovery = 0;
4016                 goto no_journal;
4017         }
4018
4019         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) &&
4020             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4021                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4022                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4023                 goto failed_mount_wq;
4024         }
4025
4026         if (!set_journal_csum_feature_set(sb)) {
4027                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4028                          "feature set");
4029                 goto failed_mount_wq;
4030         }
4031
4032         /* We have now updated the journal if required, so we can
4033          * validate the data journaling mode. */
4034         switch (test_opt(sb, DATA_FLAGS)) {
4035         case 0:
4036                 /* No mode set, assume a default based on the journal
4037                  * capabilities: ORDERED_DATA if the journal can
4038                  * cope, else JOURNAL_DATA
4039                  */
4040                 if (jbd2_journal_check_available_features
4041                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
4042                         set_opt(sb, ORDERED_DATA);
4043                 else
4044                         set_opt(sb, JOURNAL_DATA);
4045                 break;
4046
4047         case EXT4_MOUNT_ORDERED_DATA:
4048         case EXT4_MOUNT_WRITEBACK_DATA:
4049                 if (!jbd2_journal_check_available_features
4050                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4051                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4052                                "requested data journaling mode");
4053                         goto failed_mount_wq;
4054                 }
4055         default:
4056                 break;
4057         }
4058         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4059
4060         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4061
4062 no_journal:
4063         if (ext4_mballoc_ready) {
4064                 sbi->s_mb_cache = ext4_xattr_create_cache(sb->s_id);
4065                 if (!sbi->s_mb_cache) {
4066                         ext4_msg(sb, KERN_ERR, "Failed to create an mb_cache");
4067                         goto failed_mount_wq;
4068                 }
4069         }
4070
4071         if (unlikely(sbi->s_mount_flags & EXT4_MF_TEST_DUMMY_ENCRYPTION) &&
4072             !(sb->s_flags & MS_RDONLY) &&
4073             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT)) {
4074                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT);
4075                 ext4_commit_super(sb, 1);
4076         }
4077
4078         /*
4079          * Get the # of file system overhead blocks from the
4080          * superblock if present.
4081          */
4082         if (es->s_overhead_clusters)
4083                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4084         else {
4085                 err = ext4_calculate_overhead(sb);
4086                 if (err)
4087                         goto failed_mount_wq;
4088         }
4089
4090         /*
4091          * The maximum number of concurrent works can be high and
4092          * concurrency isn't really necessary.  Limit it to 1.
4093          */
4094         EXT4_SB(sb)->rsv_conversion_wq =
4095                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4096         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4097                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4098                 ret = -ENOMEM;
4099                 goto failed_mount4;
4100         }
4101
4102         /*
4103          * The jbd2_journal_load will have done any necessary log recovery,
4104          * so we can safely mount the rest of the filesystem now.
4105          */
4106
4107         root = ext4_iget(sb, EXT4_ROOT_INO);
4108         if (IS_ERR(root)) {
4109                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4110                 ret = PTR_ERR(root);
4111                 root = NULL;
4112                 goto failed_mount4;
4113         }
4114         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4115                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4116                 iput(root);
4117                 goto failed_mount4;
4118         }
4119         sb->s_root = d_make_root(root);
4120         if (!sb->s_root) {
4121                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4122                 ret = -ENOMEM;
4123                 goto failed_mount4;
4124         }
4125
4126         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
4127                 sb->s_flags |= MS_RDONLY;
4128
4129         /* determine the minimum size of new large inodes, if present */
4130         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4131                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4132                                                      EXT4_GOOD_OLD_INODE_SIZE;
4133                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
4134                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
4135                         if (sbi->s_want_extra_isize <
4136                             le16_to_cpu(es->s_want_extra_isize))
4137                                 sbi->s_want_extra_isize =
4138                                         le16_to_cpu(es->s_want_extra_isize);
4139                         if (sbi->s_want_extra_isize <
4140                             le16_to_cpu(es->s_min_extra_isize))
4141                                 sbi->s_want_extra_isize =
4142                                         le16_to_cpu(es->s_min_extra_isize);
4143                 }
4144         }
4145         /* Check if enough inode space is available */
4146         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
4147                                                         sbi->s_inode_size) {
4148                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4149                                                        EXT4_GOOD_OLD_INODE_SIZE;
4150                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
4151                          "available");
4152         }
4153
4154         err = ext4_reserve_clusters(sbi, ext4_calculate_resv_clusters(sb));
4155         if (err) {
4156                 ext4_msg(sb, KERN_ERR, "failed to reserve %llu clusters for "
4157                          "reserved pool", ext4_calculate_resv_clusters(sb));
4158                 goto failed_mount4a;
4159         }
4160
4161         err = ext4_setup_system_zone(sb);
4162         if (err) {
4163                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4164                          "zone (%d)", err);
4165                 goto failed_mount4a;
4166         }
4167
4168         ext4_ext_init(sb);
4169         err = ext4_mb_init(sb);
4170         if (err) {
4171                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4172                          err);
4173                 goto failed_mount5;
4174         }
4175
4176         block = ext4_count_free_clusters(sb);
4177         ext4_free_blocks_count_set(sbi->s_es,
4178                                    EXT4_C2B(sbi, block));
4179         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4180                                   GFP_KERNEL);
4181         if (!err) {
4182                 unsigned long freei = ext4_count_free_inodes(sb);
4183                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4184                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4185                                           GFP_KERNEL);
4186         }
4187         if (!err)
4188                 err = percpu_counter_init(&sbi->s_dirs_counter,
4189                                           ext4_count_dirs(sb), GFP_KERNEL);
4190         if (!err)
4191                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4192                                           GFP_KERNEL);
4193         if (err) {
4194                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4195                 goto failed_mount6;
4196         }
4197
4198         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
4199                 if (!ext4_fill_flex_info(sb)) {
4200                         ext4_msg(sb, KERN_ERR,
4201                                "unable to initialize "
4202                                "flex_bg meta info!");
4203                         goto failed_mount6;
4204                 }
4205
4206         err = ext4_register_li_request(sb, first_not_zeroed);
4207         if (err)
4208                 goto failed_mount6;
4209
4210         sbi->s_kobj.kset = ext4_kset;
4211         init_completion(&sbi->s_kobj_unregister);
4212         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
4213                                    "%s", sb->s_id);
4214         if (err)
4215                 goto failed_mount7;
4216
4217 #ifdef CONFIG_QUOTA
4218         /* Enable quota usage during mount. */
4219         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
4220             !(sb->s_flags & MS_RDONLY)) {
4221                 err = ext4_enable_quotas(sb);
4222                 if (err)
4223                         goto failed_mount8;
4224         }
4225 #endif  /* CONFIG_QUOTA */
4226
4227         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4228         ext4_orphan_cleanup(sb, es);
4229         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4230         if (needs_recovery) {
4231                 ext4_msg(sb, KERN_INFO, "recovery complete");
4232                 ext4_mark_recovery_complete(sb, es);
4233         }
4234         if (EXT4_SB(sb)->s_journal) {
4235                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4236                         descr = " journalled data mode";
4237                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4238                         descr = " ordered data mode";
4239                 else
4240                         descr = " writeback data mode";
4241         } else
4242                 descr = "out journal";
4243
4244         if (test_opt(sb, DISCARD)) {
4245                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4246                 if (!blk_queue_discard(q))
4247                         ext4_msg(sb, KERN_WARNING,
4248                                  "mounting with \"discard\" option, but "
4249                                  "the device does not support discard");
4250         }
4251
4252         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4253                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
4254                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4255
4256         if (es->s_error_count)
4257                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4258
4259         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4260         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4261         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4262         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4263
4264         kfree(orig_data);
4265         return 0;
4266
4267 cantfind_ext4:
4268         if (!silent)
4269                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4270         goto failed_mount;
4271
4272 #ifdef CONFIG_QUOTA
4273 failed_mount8:
4274         kobject_del(&sbi->s_kobj);
4275 #endif
4276 failed_mount7:
4277         ext4_unregister_li_request(sb);
4278 failed_mount6:
4279         ext4_mb_release(sb);
4280         if (sbi->s_flex_groups)
4281                 kvfree(sbi->s_flex_groups);
4282         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4283         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4284         percpu_counter_destroy(&sbi->s_dirs_counter);
4285         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4286 failed_mount5:
4287         ext4_ext_release(sb);
4288         ext4_release_system_zone(sb);
4289 failed_mount4a:
4290         dput(sb->s_root);
4291         sb->s_root = NULL;
4292 failed_mount4:
4293         ext4_msg(sb, KERN_ERR, "mount failed");
4294         if (EXT4_SB(sb)->rsv_conversion_wq)
4295                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4296 failed_mount_wq:
4297         if (sbi->s_journal) {
4298                 jbd2_journal_destroy(sbi->s_journal);
4299                 sbi->s_journal = NULL;
4300         }
4301 failed_mount3a:
4302         ext4_es_unregister_shrinker(sbi);
4303 failed_mount3:
4304         del_timer_sync(&sbi->s_err_report);
4305         if (sbi->s_mmp_tsk)
4306                 kthread_stop(sbi->s_mmp_tsk);
4307 failed_mount2:
4308         for (i = 0; i < db_count; i++)
4309                 brelse(sbi->s_group_desc[i]);
4310         kvfree(sbi->s_group_desc);
4311 failed_mount:
4312         if (sbi->s_chksum_driver)
4313                 crypto_free_shash(sbi->s_chksum_driver);
4314         if (sbi->s_proc) {
4315                 remove_proc_entry("options", sbi->s_proc);
4316                 remove_proc_entry(sb->s_id, ext4_proc_root);
4317         }
4318 #ifdef CONFIG_QUOTA
4319         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4320                 kfree(sbi->s_qf_names[i]);
4321 #endif
4322         ext4_blkdev_remove(sbi);
4323         brelse(bh);
4324 out_fail:
4325         sb->s_fs_info = NULL;
4326         kfree(sbi->s_blockgroup_lock);
4327         kfree(sbi);
4328 out_free_orig:
4329         kfree(orig_data);
4330         return err ? err : ret;
4331 }
4332
4333 /*
4334  * Setup any per-fs journal parameters now.  We'll do this both on
4335  * initial mount, once the journal has been initialised but before we've
4336  * done any recovery; and again on any subsequent remount.
4337  */
4338 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4339 {
4340         struct ext4_sb_info *sbi = EXT4_SB(sb);
4341
4342         journal->j_commit_interval = sbi->s_commit_interval;
4343         journal->j_min_batch_time = sbi->s_min_batch_time;
4344         journal->j_max_batch_time = sbi->s_max_batch_time;
4345
4346         write_lock(&journal->j_state_lock);
4347         if (test_opt(sb, BARRIER))
4348                 journal->j_flags |= JBD2_BARRIER;
4349         else
4350                 journal->j_flags &= ~JBD2_BARRIER;
4351         if (test_opt(sb, DATA_ERR_ABORT))
4352                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4353         else
4354                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4355         write_unlock(&journal->j_state_lock);
4356 }
4357
4358 static journal_t *ext4_get_journal(struct super_block *sb,
4359                                    unsigned int journal_inum)
4360 {
4361         struct inode *journal_inode;
4362         journal_t *journal;
4363
4364         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4365
4366         /* First, test for the existence of a valid inode on disk.  Bad
4367          * things happen if we iget() an unused inode, as the subsequent
4368          * iput() will try to delete it. */
4369
4370         journal_inode = ext4_iget(sb, journal_inum);
4371         if (IS_ERR(journal_inode)) {
4372                 ext4_msg(sb, KERN_ERR, "no journal found");
4373                 return NULL;
4374         }
4375         if (!journal_inode->i_nlink) {
4376                 make_bad_inode(journal_inode);
4377                 iput(journal_inode);
4378                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4379                 return NULL;
4380         }
4381
4382         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4383                   journal_inode, journal_inode->i_size);
4384         if (!S_ISREG(journal_inode->i_mode)) {
4385                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4386                 iput(journal_inode);
4387                 return NULL;
4388         }
4389
4390         journal = jbd2_journal_init_inode(journal_inode);
4391         if (!journal) {
4392                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4393                 iput(journal_inode);
4394                 return NULL;
4395         }
4396         journal->j_private = sb;
4397         ext4_init_journal_params(sb, journal);
4398         return journal;
4399 }
4400
4401 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4402                                        dev_t j_dev)
4403 {
4404         struct buffer_head *bh;
4405         journal_t *journal;
4406         ext4_fsblk_t start;
4407         ext4_fsblk_t len;
4408         int hblock, blocksize;
4409         ext4_fsblk_t sb_block;
4410         unsigned long offset;
4411         struct ext4_super_block *es;
4412         struct block_device *bdev;
4413
4414         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4415
4416         bdev = ext4_blkdev_get(j_dev, sb);
4417         if (bdev == NULL)
4418                 return NULL;
4419
4420         blocksize = sb->s_blocksize;
4421         hblock = bdev_logical_block_size(bdev);
4422         if (blocksize < hblock) {
4423                 ext4_msg(sb, KERN_ERR,
4424                         "blocksize too small for journal device");
4425                 goto out_bdev;
4426         }
4427
4428         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4429         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4430         set_blocksize(bdev, blocksize);
4431         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4432                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4433                        "external journal");
4434                 goto out_bdev;
4435         }
4436
4437         es = (struct ext4_super_block *) (bh->b_data + offset);
4438         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4439             !(le32_to_cpu(es->s_feature_incompat) &
4440               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4441                 ext4_msg(sb, KERN_ERR, "external journal has "
4442                                         "bad superblock");
4443                 brelse(bh);
4444                 goto out_bdev;
4445         }
4446
4447         if ((le32_to_cpu(es->s_feature_ro_compat) &
4448              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4449             es->s_checksum != ext4_superblock_csum(sb, es)) {
4450                 ext4_msg(sb, KERN_ERR, "external journal has "
4451                                        "corrupt superblock");
4452                 brelse(bh);
4453                 goto out_bdev;
4454         }
4455
4456         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4457                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4458                 brelse(bh);
4459                 goto out_bdev;
4460         }
4461
4462         len = ext4_blocks_count(es);
4463         start = sb_block + 1;
4464         brelse(bh);     /* we're done with the superblock */
4465
4466         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4467                                         start, len, blocksize);
4468         if (!journal) {
4469                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4470                 goto out_bdev;
4471         }
4472         journal->j_private = sb;
4473         ll_rw_block(READ | REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4474         wait_on_buffer(journal->j_sb_buffer);
4475         if (!buffer_uptodate(journal->j_sb_buffer)) {
4476                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4477                 goto out_journal;
4478         }
4479         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4480                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4481                                         "user (unsupported) - %d",
4482                         be32_to_cpu(journal->j_superblock->s_nr_users));
4483                 goto out_journal;
4484         }
4485         EXT4_SB(sb)->journal_bdev = bdev;
4486         ext4_init_journal_params(sb, journal);
4487         return journal;
4488
4489 out_journal:
4490         jbd2_journal_destroy(journal);
4491 out_bdev:
4492         ext4_blkdev_put(bdev);
4493         return NULL;
4494 }
4495
4496 static int ext4_load_journal(struct super_block *sb,
4497                              struct ext4_super_block *es,
4498                              unsigned long journal_devnum)
4499 {
4500         journal_t *journal;
4501         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4502         dev_t journal_dev;
4503         int err = 0;
4504         int really_read_only;
4505
4506         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4507
4508         if (journal_devnum &&
4509             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4510                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4511                         "numbers have changed");
4512                 journal_dev = new_decode_dev(journal_devnum);
4513         } else
4514                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4515
4516         really_read_only = bdev_read_only(sb->s_bdev);
4517
4518         /*
4519          * Are we loading a blank journal or performing recovery after a
4520          * crash?  For recovery, we need to check in advance whether we
4521          * can get read-write access to the device.
4522          */
4523         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4524                 if (sb->s_flags & MS_RDONLY) {
4525                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4526                                         "required on readonly filesystem");
4527                         if (really_read_only) {
4528                                 ext4_msg(sb, KERN_ERR, "write access "
4529                                         "unavailable, cannot proceed");
4530                                 return -EROFS;
4531                         }
4532                         ext4_msg(sb, KERN_INFO, "write access will "
4533                                "be enabled during recovery");
4534                 }
4535         }
4536
4537         if (journal_inum && journal_dev) {
4538                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4539                        "and inode journals!");
4540                 return -EINVAL;
4541         }
4542
4543         if (journal_inum) {
4544                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4545                         return -EINVAL;
4546         } else {
4547                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4548                         return -EINVAL;
4549         }
4550
4551         if (!(journal->j_flags & JBD2_BARRIER))
4552                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4553
4554         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4555                 err = jbd2_journal_wipe(journal, !really_read_only);
4556         if (!err) {
4557                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4558                 if (save)
4559                         memcpy(save, ((char *) es) +
4560                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4561                 err = jbd2_journal_load(journal);
4562                 if (save)
4563                         memcpy(((char *) es) + EXT4_S_ERR_START,
4564                                save, EXT4_S_ERR_LEN);
4565                 kfree(save);
4566         }
4567
4568         if (err) {
4569                 ext4_msg(sb, KERN_ERR, "error loading journal");
4570                 jbd2_journal_destroy(journal);
4571                 return err;
4572         }
4573
4574         EXT4_SB(sb)->s_journal = journal;
4575         ext4_clear_journal_err(sb, es);
4576
4577         if (!really_read_only && journal_devnum &&
4578             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4579                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4580
4581                 /* Make sure we flush the recovery flag to disk. */
4582                 ext4_commit_super(sb, 1);
4583         }
4584
4585         return 0;
4586 }
4587
4588 static int ext4_commit_super(struct super_block *sb, int sync)
4589 {
4590         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4591         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4592         int error = 0;
4593
4594         if (!sbh)
4595                 return error;
4596         if (buffer_write_io_error(sbh)) {
4597                 /*
4598                  * Oh, dear.  A previous attempt to write the
4599                  * superblock failed.  This could happen because the
4600                  * USB device was yanked out.  Or it could happen to
4601                  * be a transient write error and maybe the block will
4602                  * be remapped.  Nothing we can do but to retry the
4603                  * write and hope for the best.
4604                  */
4605                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4606                        "superblock detected");
4607                 clear_buffer_write_io_error(sbh);
4608                 set_buffer_uptodate(sbh);
4609         }
4610         /*
4611          * If the file system is mounted read-only, don't update the
4612          * superblock write time.  This avoids updating the superblock
4613          * write time when we are mounting the root file system
4614          * read/only but we need to replay the journal; at that point,
4615          * for people who are east of GMT and who make their clock
4616          * tick in localtime for Windows bug-for-bug compatibility,
4617          * the clock is set in the future, and this will cause e2fsck
4618          * to complain and force a full file system check.
4619          */
4620         if (!(sb->s_flags & MS_RDONLY))
4621                 es->s_wtime = cpu_to_le32(get_seconds());
4622         if (sb->s_bdev->bd_part)
4623                 es->s_kbytes_written =
4624                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4625                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4626                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4627         else
4628                 es->s_kbytes_written =
4629                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4630         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4631                 ext4_free_blocks_count_set(es,
4632                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4633                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4634         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4635                 es->s_free_inodes_count =
4636                         cpu_to_le32(percpu_counter_sum_positive(
4637                                 &EXT4_SB(sb)->s_freeinodes_counter));
4638         BUFFER_TRACE(sbh, "marking dirty");
4639         ext4_superblock_csum_set(sb);
4640         mark_buffer_dirty(sbh);
4641         if (sync) {
4642                 error = sync_dirty_buffer(sbh);
4643                 if (error)
4644                         return error;
4645
4646                 error = buffer_write_io_error(sbh);
4647                 if (error) {
4648                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4649                                "superblock");
4650                         clear_buffer_write_io_error(sbh);
4651                         set_buffer_uptodate(sbh);
4652                 }
4653         }
4654         return error;
4655 }
4656
4657 /*
4658  * Have we just finished recovery?  If so, and if we are mounting (or
4659  * remounting) the filesystem readonly, then we will end up with a
4660  * consistent fs on disk.  Record that fact.
4661  */
4662 static void ext4_mark_recovery_complete(struct super_block *sb,
4663                                         struct ext4_super_block *es)
4664 {
4665         journal_t *journal = EXT4_SB(sb)->s_journal;
4666
4667         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4668                 BUG_ON(journal != NULL);
4669                 return;
4670         }
4671         jbd2_journal_lock_updates(journal);
4672         if (jbd2_journal_flush(journal) < 0)
4673                 goto out;
4674
4675         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4676             sb->s_flags & MS_RDONLY) {
4677                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4678                 ext4_commit_super(sb, 1);
4679         }
4680
4681 out:
4682         jbd2_journal_unlock_updates(journal);
4683 }
4684
4685 /*
4686  * If we are mounting (or read-write remounting) a filesystem whose journal
4687  * has recorded an error from a previous lifetime, move that error to the
4688  * main filesystem now.
4689  */
4690 static void ext4_clear_journal_err(struct super_block *sb,
4691                                    struct ext4_super_block *es)
4692 {
4693         journal_t *journal;
4694         int j_errno;
4695         const char *errstr;
4696
4697         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4698
4699         journal = EXT4_SB(sb)->s_journal;
4700
4701         /*
4702          * Now check for any error status which may have been recorded in the
4703          * journal by a prior ext4_error() or ext4_abort()
4704          */
4705
4706         j_errno = jbd2_journal_errno(journal);
4707         if (j_errno) {
4708                 char nbuf[16];
4709
4710                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4711                 ext4_warning(sb, "Filesystem error recorded "
4712                              "from previous mount: %s", errstr);
4713                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4714
4715                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4716                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4717                 ext4_commit_super(sb, 1);
4718
4719                 jbd2_journal_clear_err(journal);
4720                 jbd2_journal_update_sb_errno(journal);
4721         }
4722 }
4723
4724 /*
4725  * Force the running and committing transactions to commit,
4726  * and wait on the commit.
4727  */
4728 int ext4_force_commit(struct super_block *sb)
4729 {
4730         journal_t *journal;
4731
4732         if (sb->s_flags & MS_RDONLY)
4733                 return 0;
4734
4735         journal = EXT4_SB(sb)->s_journal;
4736         return ext4_journal_force_commit(journal);
4737 }
4738
4739 static int ext4_sync_fs(struct super_block *sb, int wait)
4740 {
4741         int ret = 0;
4742         tid_t target;
4743         bool needs_barrier = false;
4744         struct ext4_sb_info *sbi = EXT4_SB(sb);
4745
4746         trace_ext4_sync_fs(sb, wait);
4747         flush_workqueue(sbi->rsv_conversion_wq);
4748         /*
4749          * Writeback quota in non-journalled quota case - journalled quota has
4750          * no dirty dquots
4751          */
4752         dquot_writeback_dquots(sb, -1);
4753         /*
4754          * Data writeback is possible w/o journal transaction, so barrier must
4755          * being sent at the end of the function. But we can skip it if
4756          * transaction_commit will do it for us.
4757          */
4758         if (sbi->s_journal) {
4759                 target = jbd2_get_latest_transaction(sbi->s_journal);
4760                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
4761                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
4762                         needs_barrier = true;
4763
4764                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4765                         if (wait)
4766                                 ret = jbd2_log_wait_commit(sbi->s_journal,
4767                                                            target);
4768                 }
4769         } else if (wait && test_opt(sb, BARRIER))
4770                 needs_barrier = true;
4771         if (needs_barrier) {
4772                 int err;
4773                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4774                 if (!ret)
4775                         ret = err;
4776         }
4777
4778         return ret;
4779 }
4780
4781 /*
4782  * LVM calls this function before a (read-only) snapshot is created.  This
4783  * gives us a chance to flush the journal completely and mark the fs clean.
4784  *
4785  * Note that only this function cannot bring a filesystem to be in a clean
4786  * state independently. It relies on upper layer to stop all data & metadata
4787  * modifications.
4788  */
4789 static int ext4_freeze(struct super_block *sb)
4790 {
4791         int error = 0;
4792         journal_t *journal;
4793
4794         if (sb->s_flags & MS_RDONLY)
4795                 return 0;
4796
4797         journal = EXT4_SB(sb)->s_journal;
4798
4799         if (journal) {
4800                 /* Now we set up the journal barrier. */
4801                 jbd2_journal_lock_updates(journal);
4802
4803                 /*
4804                  * Don't clear the needs_recovery flag if we failed to
4805                  * flush the journal.
4806                  */
4807                 error = jbd2_journal_flush(journal);
4808                 if (error < 0)
4809                         goto out;
4810         }
4811
4812         /* Journal blocked and flushed, clear needs_recovery flag. */
4813         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4814         error = ext4_commit_super(sb, 1);
4815 out:
4816         if (journal)
4817                 /* we rely on upper layer to stop further updates */
4818                 jbd2_journal_unlock_updates(journal);
4819         return error;
4820 }
4821
4822 /*
4823  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4824  * flag here, even though the filesystem is not technically dirty yet.
4825  */
4826 static int ext4_unfreeze(struct super_block *sb)
4827 {
4828         if (sb->s_flags & MS_RDONLY)
4829                 return 0;
4830
4831         /* Reset the needs_recovery flag before the fs is unlocked. */
4832         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4833         ext4_commit_super(sb, 1);
4834         return 0;
4835 }
4836
4837 /*
4838  * Structure to save mount options for ext4_remount's benefit
4839  */
4840 struct ext4_mount_options {
4841         unsigned long s_mount_opt;
4842         unsigned long s_mount_opt2;
4843         kuid_t s_resuid;
4844         kgid_t s_resgid;
4845         unsigned long s_commit_interval;
4846         u32 s_min_batch_time, s_max_batch_time;
4847 #ifdef CONFIG_QUOTA
4848         int s_jquota_fmt;
4849         char *s_qf_names[EXT4_MAXQUOTAS];
4850 #endif
4851 };
4852
4853 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4854 {
4855         struct ext4_super_block *es;
4856         struct ext4_sb_info *sbi = EXT4_SB(sb);
4857         unsigned long old_sb_flags;
4858         struct ext4_mount_options old_opts;
4859         int enable_quota = 0;
4860         ext4_group_t g;
4861         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4862         int err = 0;
4863 #ifdef CONFIG_QUOTA
4864         int i, j;
4865 #endif
4866         char *orig_data = kstrdup(data, GFP_KERNEL);
4867
4868         /* Store the original options */
4869         old_sb_flags = sb->s_flags;
4870         old_opts.s_mount_opt = sbi->s_mount_opt;
4871         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4872         old_opts.s_resuid = sbi->s_resuid;
4873         old_opts.s_resgid = sbi->s_resgid;
4874         old_opts.s_commit_interval = sbi->s_commit_interval;
4875         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4876         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4877 #ifdef CONFIG_QUOTA
4878         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4879         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4880                 if (sbi->s_qf_names[i]) {
4881                         old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
4882                                                          GFP_KERNEL);
4883                         if (!old_opts.s_qf_names[i]) {
4884                                 for (j = 0; j < i; j++)
4885                                         kfree(old_opts.s_qf_names[j]);
4886                                 kfree(orig_data);
4887                                 return -ENOMEM;
4888                         }
4889                 } else
4890                         old_opts.s_qf_names[i] = NULL;
4891 #endif
4892         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4893                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4894
4895         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4896                 err = -EINVAL;
4897                 goto restore_opts;
4898         }
4899
4900         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
4901             test_opt(sb, JOURNAL_CHECKSUM)) {
4902                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
4903                          "during remount not supported; ignoring");
4904                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
4905         }
4906
4907         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4908                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4909                         ext4_msg(sb, KERN_ERR, "can't mount with "
4910                                  "both data=journal and delalloc");
4911                         err = -EINVAL;
4912                         goto restore_opts;
4913                 }
4914                 if (test_opt(sb, DIOREAD_NOLOCK)) {
4915                         ext4_msg(sb, KERN_ERR, "can't mount with "
4916                                  "both data=journal and dioread_nolock");
4917                         err = -EINVAL;
4918                         goto restore_opts;
4919                 }
4920                 if (test_opt(sb, DAX)) {
4921                         ext4_msg(sb, KERN_ERR, "can't mount with "
4922                                  "both data=journal and dax");
4923                         err = -EINVAL;
4924                         goto restore_opts;
4925                 }
4926         }
4927
4928         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
4929                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
4930                         "dax flag with busy inodes while remounting");
4931                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
4932         }
4933
4934         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4935                 ext4_abort(sb, "Abort forced by user");
4936
4937         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4938                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4939
4940         es = sbi->s_es;
4941
4942         if (sbi->s_journal) {
4943                 ext4_init_journal_params(sb, sbi->s_journal);
4944                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4945         }
4946
4947         if (*flags & MS_LAZYTIME)
4948                 sb->s_flags |= MS_LAZYTIME;
4949
4950         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4951                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4952                         err = -EROFS;
4953                         goto restore_opts;
4954                 }
4955
4956                 if (*flags & MS_RDONLY) {
4957                         err = sync_filesystem(sb);
4958                         if (err < 0)
4959                                 goto restore_opts;
4960                         err = dquot_suspend(sb, -1);
4961                         if (err < 0)
4962                                 goto restore_opts;
4963
4964                         /*
4965                          * First of all, the unconditional stuff we have to do
4966                          * to disable replay of the journal when we next remount
4967                          */
4968                         sb->s_flags |= MS_RDONLY;
4969
4970                         /*
4971                          * OK, test if we are remounting a valid rw partition
4972                          * readonly, and if so set the rdonly flag and then
4973                          * mark the partition as valid again.
4974                          */
4975                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4976                             (sbi->s_mount_state & EXT4_VALID_FS))
4977                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4978
4979                         if (sbi->s_journal)
4980                                 ext4_mark_recovery_complete(sb, es);
4981                 } else {
4982                         /* Make sure we can mount this feature set readwrite */
4983                         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
4984                                         EXT4_FEATURE_RO_COMPAT_READONLY) ||
4985                             !ext4_feature_set_ok(sb, 0)) {
4986                                 err = -EROFS;
4987                                 goto restore_opts;
4988                         }
4989                         /*
4990                          * Make sure the group descriptor checksums
4991                          * are sane.  If they aren't, refuse to remount r/w.
4992                          */
4993                         for (g = 0; g < sbi->s_groups_count; g++) {
4994                                 struct ext4_group_desc *gdp =
4995                                         ext4_get_group_desc(sb, g, NULL);
4996
4997                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
4998                                         ext4_msg(sb, KERN_ERR,
4999                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5000                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
5001                                                le16_to_cpu(gdp->bg_checksum));
5002                                         err = -EINVAL;
5003                                         goto restore_opts;
5004                                 }
5005                         }
5006
5007                         /*
5008                          * If we have an unprocessed orphan list hanging
5009                          * around from a previously readonly bdev mount,
5010                          * require a full umount/remount for now.
5011                          */
5012                         if (es->s_last_orphan) {
5013                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5014                                        "remount RDWR because of unprocessed "
5015                                        "orphan inode list.  Please "
5016                                        "umount/remount instead");
5017                                 err = -EINVAL;
5018                                 goto restore_opts;
5019                         }
5020
5021                         /*
5022                          * Mounting a RDONLY partition read-write, so reread
5023                          * and store the current valid flag.  (It may have
5024                          * been changed by e2fsck since we originally mounted
5025                          * the partition.)
5026                          */
5027                         if (sbi->s_journal)
5028                                 ext4_clear_journal_err(sb, es);
5029                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5030                         if (!ext4_setup_super(sb, es, 0))
5031                                 sb->s_flags &= ~MS_RDONLY;
5032                         if (EXT4_HAS_INCOMPAT_FEATURE(sb,
5033                                                      EXT4_FEATURE_INCOMPAT_MMP))
5034                                 if (ext4_multi_mount_protect(sb,
5035                                                 le64_to_cpu(es->s_mmp_block))) {
5036                                         err = -EROFS;
5037                                         goto restore_opts;
5038                                 }
5039                         enable_quota = 1;
5040                 }
5041         }
5042
5043         /*
5044          * Reinitialize lazy itable initialization thread based on
5045          * current settings
5046          */
5047         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
5048                 ext4_unregister_li_request(sb);
5049         else {
5050                 ext4_group_t first_not_zeroed;
5051                 first_not_zeroed = ext4_has_uninit_itable(sb);
5052                 ext4_register_li_request(sb, first_not_zeroed);
5053         }
5054
5055         ext4_setup_system_zone(sb);
5056         if (sbi->s_journal == NULL && !(old_sb_flags & MS_RDONLY))
5057                 ext4_commit_super(sb, 1);
5058
5059 #ifdef CONFIG_QUOTA
5060         /* Release old quota file names */
5061         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5062                 kfree(old_opts.s_qf_names[i]);
5063         if (enable_quota) {
5064                 if (sb_any_quota_suspended(sb))
5065                         dquot_resume(sb, -1);
5066                 else if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
5067                                         EXT4_FEATURE_RO_COMPAT_QUOTA)) {
5068                         err = ext4_enable_quotas(sb);
5069                         if (err)
5070                                 goto restore_opts;
5071                 }
5072         }
5073 #endif
5074
5075         *flags = (*flags & ~MS_LAZYTIME) | (sb->s_flags & MS_LAZYTIME);
5076         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5077         kfree(orig_data);
5078         return 0;
5079
5080 restore_opts:
5081         sb->s_flags = old_sb_flags;
5082         sbi->s_mount_opt = old_opts.s_mount_opt;
5083         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5084         sbi->s_resuid = old_opts.s_resuid;
5085         sbi->s_resgid = old_opts.s_resgid;
5086         sbi->s_commit_interval = old_opts.s_commit_interval;
5087         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5088         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5089 #ifdef CONFIG_QUOTA
5090         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5091         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5092                 kfree(sbi->s_qf_names[i]);
5093                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
5094         }
5095 #endif
5096         kfree(orig_data);
5097         return err;
5098 }
5099
5100 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5101 {
5102         struct super_block *sb = dentry->d_sb;
5103         struct ext4_sb_info *sbi = EXT4_SB(sb);
5104         struct ext4_super_block *es = sbi->s_es;
5105         ext4_fsblk_t overhead = 0, resv_blocks;
5106         u64 fsid;
5107         s64 bfree;
5108         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5109
5110         if (!test_opt(sb, MINIX_DF))
5111                 overhead = sbi->s_overhead;
5112
5113         buf->f_type = EXT4_SUPER_MAGIC;
5114         buf->f_bsize = sb->s_blocksize;
5115         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5116         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5117                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5118         /* prevent underflow in case that few free space is available */
5119         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5120         buf->f_bavail = buf->f_bfree -
5121                         (ext4_r_blocks_count(es) + resv_blocks);
5122         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5123                 buf->f_bavail = 0;
5124         buf->f_files = le32_to_cpu(es->s_inodes_count);
5125         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5126         buf->f_namelen = EXT4_NAME_LEN;
5127         fsid = le64_to_cpup((void *)es->s_uuid) ^
5128                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5129         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5130         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5131
5132         return 0;
5133 }
5134
5135 /* Helper function for writing quotas on sync - we need to start transaction
5136  * before quota file is locked for write. Otherwise the are possible deadlocks:
5137  * Process 1                         Process 2
5138  * ext4_create()                     quota_sync()
5139  *   jbd2_journal_start()                  write_dquot()
5140  *   dquot_initialize()                         down(dqio_mutex)
5141  *     down(dqio_mutex)                    jbd2_journal_start()
5142  *
5143  */
5144
5145 #ifdef CONFIG_QUOTA
5146
5147 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5148 {
5149         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5150 }
5151
5152 static int ext4_write_dquot(struct dquot *dquot)
5153 {
5154         int ret, err;
5155         handle_t *handle;
5156         struct inode *inode;
5157
5158         inode = dquot_to_inode(dquot);
5159         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5160                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5161         if (IS_ERR(handle))
5162                 return PTR_ERR(handle);
5163         ret = dquot_commit(dquot);
5164         err = ext4_journal_stop(handle);
5165         if (!ret)
5166                 ret = err;
5167         return ret;
5168 }
5169
5170 static int ext4_acquire_dquot(struct dquot *dquot)
5171 {
5172         int ret, err;
5173         handle_t *handle;
5174
5175         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5176                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5177         if (IS_ERR(handle))
5178                 return PTR_ERR(handle);
5179         ret = dquot_acquire(dquot);
5180         err = ext4_journal_stop(handle);
5181         if (!ret)
5182                 ret = err;
5183         return ret;
5184 }
5185
5186 static int ext4_release_dquot(struct dquot *dquot)
5187 {
5188         int ret, err;
5189         handle_t *handle;
5190
5191         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5192                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5193         if (IS_ERR(handle)) {
5194                 /* Release dquot anyway to avoid endless cycle in dqput() */
5195                 dquot_release(dquot);
5196                 return PTR_ERR(handle);
5197         }
5198         ret = dquot_release(dquot);
5199         err = ext4_journal_stop(handle);
5200         if (!ret)
5201                 ret = err;
5202         return ret;
5203 }
5204
5205 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5206 {
5207         struct super_block *sb = dquot->dq_sb;
5208         struct ext4_sb_info *sbi = EXT4_SB(sb);
5209
5210         /* Are we journaling quotas? */
5211         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) ||
5212             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5213                 dquot_mark_dquot_dirty(dquot);
5214                 return ext4_write_dquot(dquot);
5215         } else {
5216                 return dquot_mark_dquot_dirty(dquot);
5217         }
5218 }
5219
5220 static int ext4_write_info(struct super_block *sb, int type)
5221 {
5222         int ret, err;
5223         handle_t *handle;
5224
5225         /* Data block + inode block */
5226         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5227         if (IS_ERR(handle))
5228                 return PTR_ERR(handle);
5229         ret = dquot_commit_info(sb, type);
5230         err = ext4_journal_stop(handle);
5231         if (!ret)
5232                 ret = err;
5233         return ret;
5234 }
5235
5236 /*
5237  * Turn on quotas during mount time - we need to find
5238  * the quota file and such...
5239  */
5240 static int ext4_quota_on_mount(struct super_block *sb, int type)
5241 {
5242         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
5243                                         EXT4_SB(sb)->s_jquota_fmt, type);
5244 }
5245
5246 /*
5247  * Standard function to be called on quota_on
5248  */
5249 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5250                          struct path *path)
5251 {
5252         int err;
5253
5254         if (!test_opt(sb, QUOTA))
5255                 return -EINVAL;
5256
5257         /* Quotafile not on the same filesystem? */
5258         if (path->dentry->d_sb != sb)
5259                 return -EXDEV;
5260         /* Journaling quota? */
5261         if (EXT4_SB(sb)->s_qf_names[type]) {
5262                 /* Quotafile not in fs root? */
5263                 if (path->dentry->d_parent != sb->s_root)
5264                         ext4_msg(sb, KERN_WARNING,
5265                                 "Quota file not on filesystem root. "
5266                                 "Journaled quota will not work");
5267         }
5268
5269         /*
5270          * When we journal data on quota file, we have to flush journal to see
5271          * all updates to the file when we bypass pagecache...
5272          */
5273         if (EXT4_SB(sb)->s_journal &&
5274             ext4_should_journal_data(d_inode(path->dentry))) {
5275                 /*
5276                  * We don't need to lock updates but journal_flush() could
5277                  * otherwise be livelocked...
5278                  */
5279                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5280                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5281                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5282                 if (err)
5283                         return err;
5284         }
5285
5286         return dquot_quota_on(sb, type, format_id, path);
5287 }
5288
5289 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5290                              unsigned int flags)
5291 {
5292         int err;
5293         struct inode *qf_inode;
5294         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5295                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5296                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
5297         };
5298
5299         BUG_ON(!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA));
5300
5301         if (!qf_inums[type])
5302                 return -EPERM;
5303
5304         qf_inode = ext4_iget(sb, qf_inums[type]);
5305         if (IS_ERR(qf_inode)) {
5306                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5307                 return PTR_ERR(qf_inode);
5308         }
5309
5310         /* Don't account quota for quota files to avoid recursion */
5311         qf_inode->i_flags |= S_NOQUOTA;
5312         err = dquot_enable(qf_inode, type, format_id, flags);
5313         iput(qf_inode);
5314
5315         return err;
5316 }
5317
5318 /* Enable usage tracking for all quota types. */
5319 static int ext4_enable_quotas(struct super_block *sb)
5320 {
5321         int type, err = 0;
5322         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5323                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5324                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
5325         };
5326
5327         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
5328         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5329                 if (qf_inums[type]) {
5330                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5331                                                 DQUOT_USAGE_ENABLED);
5332                         if (err) {
5333                                 ext4_warning(sb,
5334                                         "Failed to enable quota tracking "
5335                                         "(type=%d, err=%d). Please run "
5336                                         "e2fsck to fix.", type, err);
5337                                 return err;
5338                         }
5339                 }
5340         }
5341         return 0;
5342 }
5343
5344 static int ext4_quota_off(struct super_block *sb, int type)
5345 {
5346         struct inode *inode = sb_dqopt(sb)->files[type];
5347         handle_t *handle;
5348
5349         /* Force all delayed allocation blocks to be allocated.
5350          * Caller already holds s_umount sem */
5351         if (test_opt(sb, DELALLOC))
5352                 sync_filesystem(sb);
5353
5354         if (!inode)
5355                 goto out;
5356
5357         /* Update modification times of quota files when userspace can
5358          * start looking at them */
5359         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5360         if (IS_ERR(handle))
5361                 goto out;
5362         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
5363         ext4_mark_inode_dirty(handle, inode);
5364         ext4_journal_stop(handle);
5365
5366 out:
5367         return dquot_quota_off(sb, type);
5368 }
5369
5370 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5371  * acquiring the locks... As quota files are never truncated and quota code
5372  * itself serializes the operations (and no one else should touch the files)
5373  * we don't have to be afraid of races */
5374 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5375                                size_t len, loff_t off)
5376 {
5377         struct inode *inode = sb_dqopt(sb)->files[type];
5378         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5379         int offset = off & (sb->s_blocksize - 1);
5380         int tocopy;
5381         size_t toread;
5382         struct buffer_head *bh;
5383         loff_t i_size = i_size_read(inode);
5384
5385         if (off > i_size)
5386                 return 0;
5387         if (off+len > i_size)
5388                 len = i_size-off;
5389         toread = len;
5390         while (toread > 0) {
5391                 tocopy = sb->s_blocksize - offset < toread ?
5392                                 sb->s_blocksize - offset : toread;
5393                 bh = ext4_bread(NULL, inode, blk, 0);
5394                 if (IS_ERR(bh))
5395                         return PTR_ERR(bh);
5396                 if (!bh)        /* A hole? */
5397                         memset(data, 0, tocopy);
5398                 else
5399                         memcpy(data, bh->b_data+offset, tocopy);
5400                 brelse(bh);
5401                 offset = 0;
5402                 toread -= tocopy;
5403                 data += tocopy;
5404                 blk++;
5405         }
5406         return len;
5407 }
5408
5409 /* Write to quotafile (we know the transaction is already started and has
5410  * enough credits) */
5411 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5412                                 const char *data, size_t len, loff_t off)
5413 {
5414         struct inode *inode = sb_dqopt(sb)->files[type];
5415         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5416         int err, offset = off & (sb->s_blocksize - 1);
5417         struct buffer_head *bh;
5418         handle_t *handle = journal_current_handle();
5419
5420         if (EXT4_SB(sb)->s_journal && !handle) {
5421                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5422                         " cancelled because transaction is not started",
5423                         (unsigned long long)off, (unsigned long long)len);
5424                 return -EIO;
5425         }
5426         /*
5427          * Since we account only one data block in transaction credits,
5428          * then it is impossible to cross a block boundary.
5429          */
5430         if (sb->s_blocksize - offset < len) {
5431                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5432                         " cancelled because not block aligned",
5433                         (unsigned long long)off, (unsigned long long)len);
5434                 return -EIO;
5435         }
5436
5437         bh = ext4_bread(handle, inode, blk, 1);
5438         if (IS_ERR(bh))
5439                 return PTR_ERR(bh);
5440         if (!bh)
5441                 goto out;
5442         BUFFER_TRACE(bh, "get write access");
5443         err = ext4_journal_get_write_access(handle, bh);
5444         if (err) {
5445                 brelse(bh);
5446                 return err;
5447         }
5448         lock_buffer(bh);
5449         memcpy(bh->b_data+offset, data, len);
5450         flush_dcache_page(bh->b_page);
5451         unlock_buffer(bh);
5452         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5453         brelse(bh);
5454 out:
5455         if (inode->i_size < off + len) {
5456                 i_size_write(inode, off + len);
5457                 EXT4_I(inode)->i_disksize = inode->i_size;
5458                 ext4_mark_inode_dirty(handle, inode);
5459         }
5460         return len;
5461 }
5462
5463 #endif
5464
5465 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5466                        const char *dev_name, void *data)
5467 {
5468         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5469 }
5470
5471 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5472 static inline void register_as_ext2(void)
5473 {
5474         int err = register_filesystem(&ext2_fs_type);
5475         if (err)
5476                 printk(KERN_WARNING
5477                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5478 }
5479
5480 static inline void unregister_as_ext2(void)
5481 {
5482         unregister_filesystem(&ext2_fs_type);
5483 }
5484
5485 static inline int ext2_feature_set_ok(struct super_block *sb)
5486 {
5487         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
5488                 return 0;
5489         if (sb->s_flags & MS_RDONLY)
5490                 return 1;
5491         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
5492                 return 0;
5493         return 1;
5494 }
5495 #else
5496 static inline void register_as_ext2(void) { }
5497 static inline void unregister_as_ext2(void) { }
5498 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5499 #endif
5500
5501 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5502 static inline void register_as_ext3(void)
5503 {
5504         int err = register_filesystem(&ext3_fs_type);
5505         if (err)
5506                 printk(KERN_WARNING
5507                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5508 }
5509
5510 static inline void unregister_as_ext3(void)
5511 {
5512         unregister_filesystem(&ext3_fs_type);
5513 }
5514
5515 static inline int ext3_feature_set_ok(struct super_block *sb)
5516 {
5517         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
5518                 return 0;
5519         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
5520                 return 0;
5521         if (sb->s_flags & MS_RDONLY)
5522                 return 1;
5523         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
5524                 return 0;
5525         return 1;
5526 }
5527 #else
5528 static inline void register_as_ext3(void) { }
5529 static inline void unregister_as_ext3(void) { }
5530 static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
5531 #endif
5532
5533 static struct file_system_type ext4_fs_type = {
5534         .owner          = THIS_MODULE,
5535         .name           = "ext4",
5536         .mount          = ext4_mount,
5537         .kill_sb        = kill_block_super,
5538         .fs_flags       = FS_REQUIRES_DEV,
5539 };
5540 MODULE_ALIAS_FS("ext4");
5541
5542 static int __init ext4_init_feat_adverts(void)
5543 {
5544         struct ext4_features *ef;
5545         int ret = -ENOMEM;
5546
5547         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
5548         if (!ef)
5549                 goto out;
5550
5551         ef->f_kobj.kset = ext4_kset;
5552         init_completion(&ef->f_kobj_unregister);
5553         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
5554                                    "features");
5555         if (ret) {
5556                 kfree(ef);
5557                 goto out;
5558         }
5559
5560         ext4_feat = ef;
5561         ret = 0;
5562 out:
5563         return ret;
5564 }
5565
5566 static void ext4_exit_feat_adverts(void)
5567 {
5568         kobject_put(&ext4_feat->f_kobj);
5569         wait_for_completion(&ext4_feat->f_kobj_unregister);
5570         kfree(ext4_feat);
5571 }
5572
5573 /* Shared across all ext4 file systems */
5574 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5575 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5576
5577 static int __init ext4_init_fs(void)
5578 {
5579         int i, err;
5580
5581         ext4_li_info = NULL;
5582         mutex_init(&ext4_li_mtx);
5583
5584         /* Build-time check for flags consistency */
5585         ext4_check_flag_values();
5586
5587         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5588                 mutex_init(&ext4__aio_mutex[i]);
5589                 init_waitqueue_head(&ext4__ioend_wq[i]);
5590         }
5591
5592         err = ext4_init_es();
5593         if (err)
5594                 return err;
5595
5596         err = ext4_init_pageio();
5597         if (err)
5598                 goto out7;
5599
5600         err = ext4_init_system_zone();
5601         if (err)
5602                 goto out6;
5603         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
5604         if (!ext4_kset) {
5605                 err = -ENOMEM;
5606                 goto out5;
5607         }
5608         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
5609
5610         err = ext4_init_feat_adverts();
5611         if (err)
5612                 goto out4;
5613
5614         err = ext4_init_mballoc();
5615         if (err)
5616                 goto out2;
5617         else
5618                 ext4_mballoc_ready = 1;
5619         err = init_inodecache();
5620         if (err)
5621                 goto out1;
5622         register_as_ext3();
5623         register_as_ext2();
5624         err = register_filesystem(&ext4_fs_type);
5625         if (err)
5626                 goto out;
5627
5628         return 0;
5629 out:
5630         unregister_as_ext2();
5631         unregister_as_ext3();
5632         destroy_inodecache();
5633 out1:
5634         ext4_mballoc_ready = 0;
5635         ext4_exit_mballoc();
5636 out2:
5637         ext4_exit_feat_adverts();
5638 out4:
5639         if (ext4_proc_root)
5640                 remove_proc_entry("fs/ext4", NULL);
5641         kset_unregister(ext4_kset);
5642 out5:
5643         ext4_exit_system_zone();
5644 out6:
5645         ext4_exit_pageio();
5646 out7:
5647         ext4_exit_es();
5648
5649         return err;
5650 }
5651
5652 static void __exit ext4_exit_fs(void)
5653 {
5654         ext4_destroy_lazyinit_thread();
5655         unregister_as_ext2();
5656         unregister_as_ext3();
5657         unregister_filesystem(&ext4_fs_type);
5658         destroy_inodecache();
5659         ext4_exit_mballoc();
5660         ext4_exit_feat_adverts();
5661         remove_proc_entry("fs/ext4", NULL);
5662         kset_unregister(ext4_kset);
5663         ext4_exit_system_zone();
5664         ext4_exit_pageio();
5665         ext4_exit_es();
5666 }
5667
5668 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5669 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5670 MODULE_LICENSE("GPL");
5671 module_init(ext4_init_fs)
5672 module_exit(ext4_exit_fs)