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 #define ext4_warning_ratelimit(sb)                                      \
 595                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 596                              "EXT4-fs warning")
 597
 598 void __ext4_warning(struct super_block *sb, const char *function,
 599                     unsigned int line, const char *fmt, ...)
 600 {
 601         struct va_format vaf;
 602         va_list args;
 603
 604         if (!ext4_warning_ratelimit(sb))
 605                 return;
 606
 607         va_start(args, fmt);
 608         vaf.fmt = fmt;
 609         vaf.va = &args;
 610         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 611                sb->s_id, function, line, &vaf);
 612         va_end(args);
 613 }
 614
 615 void __ext4_warning_inode(const struct inode *inode, const char *function,
 616                           unsigned int line, const char *fmt, ...)
 617 {
 618         struct va_format vaf;
 619         va_list args;
 620
 621         if (!ext4_warning_ratelimit(inode->i_sb))
 622                 return;
 623
 624         va_start(args, fmt);
 625         vaf.fmt = fmt;
 626         vaf.va = &args;
 627         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 628                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 629                function, line, inode->i_ino, current->comm, &vaf);
 630         va_end(args);
 631 }
 632
 633 void __ext4_grp_locked_error(const char *function, unsigned int line,
 634                              struct super_block *sb, ext4_group_t grp,
 635                              unsigned long ino, ext4_fsblk_t block,
 636                              const char *fmt, ...)
 637 __releases(bitlock)
 638 __acquires(bitlock)
 639 {
 640         struct va_format vaf;
 641         va_list args;
 642         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 643
 644         es->s_last_error_ino = cpu_to_le32(ino);
 645         es->s_last_error_block = cpu_to_le64(block);
 646         __save_error_info(sb, function, line);
 647
 648         if (ext4_error_ratelimit(sb)) {
 649                 va_start(args, fmt);
 650                 vaf.fmt = fmt;
 651                 vaf.va = &args;
 652                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 653                        sb->s_id, function, line, grp);
 654                 if (ino)
 655                         printk(KERN_CONT "inode %lu: ", ino);
 656                 if (block)
 657                         printk(KERN_CONT "block %llu:",
 658                                (unsigned long long) block);
 659                 printk(KERN_CONT "%pV\n", &vaf);
 660                 va_end(args);
 661         }
 662
 663         if (test_opt(sb, ERRORS_CONT)) {
 664                 ext4_commit_super(sb, 0);
 665                 return;
 666         }
 667
 668         ext4_unlock_group(sb, grp);
 669         ext4_handle_error(sb);
 670         /*
 671          * We only get here in the ERRORS_RO case; relocking the group
 672          * may be dangerous, but nothing bad will happen since the
 673          * filesystem will have already been marked read/only and the
 674          * journal has been aborted.  We return 1 as a hint to callers
 675          * who might what to use the return value from
 676          * ext4_grp_locked_error() to distinguish between the
 677          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 678          * aggressively from the ext4 function in question, with a
 679          * more appropriate error code.
 680          */
 681         ext4_lock_group(sb, grp);
 682         return;
 683 }
 684
 685 void ext4_update_dynamic_rev(struct super_block *sb)
 686 {
 687         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 688
 689         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 690                 return;
 691
 692         ext4_warning(sb,
 693                      "updating to rev %d because of new feature flag, "
 694                      "running e2fsck is recommended",
 695                      EXT4_DYNAMIC_REV);
 696
 697         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 698         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 699         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 700         /* leave es->s_feature_*compat flags alone */
 701         /* es->s_uuid will be set by e2fsck if empty */
 702
 703         /*
 704          * The rest of the superblock fields should be zero, and if not it
 705          * means they are likely already in use, so leave them alone.  We
 706          * can leave it up to e2fsck to clean up any inconsistencies there.
 707          */
 708 }
 709
 710 /*
 711  * Open the external journal device
 712  */
 713 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 714 {
 715         struct block_device *bdev;
 716         char b[BDEVNAME_SIZE];
 717
 718         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 719         if (IS_ERR(bdev))
 720                 goto fail;
 721         return bdev;
 722
 723 fail:
 724         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 725                         __bdevname(dev, b), PTR_ERR(bdev));
 726         return NULL;
 727 }
 728
 729 /*
 730  * Release the journal device
 731  */
 732 static void ext4_blkdev_put(struct block_device *bdev)
 733 {
 734         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 735 }
 736
 737 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 738 {
 739         struct block_device *bdev;
 740         bdev = sbi->journal_bdev;
 741         if (bdev) {
 742                 ext4_blkdev_put(bdev);
 743                 sbi->journal_bdev = NULL;
 744         }
 745 }
 746
 747 static inline struct inode *orphan_list_entry(struct list_head *l)
 748 {
 749         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 750 }
 751
 752 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 753 {
 754         struct list_head *l;
 755
 756         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 757                  le32_to_cpu(sbi->s_es->s_last_orphan));
 758
 759         printk(KERN_ERR "sb_info orphan list:\n");
 760         list_for_each(l, &sbi->s_orphan) {
 761                 struct inode *inode = orphan_list_entry(l);
 762                 printk(KERN_ERR "  "
 763                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 764                        inode->i_sb->s_id, inode->i_ino, inode,
 765                        inode->i_mode, inode->i_nlink,
 766                        NEXT_ORPHAN(inode));
 767         }
 768 }
 769
 770 static void ext4_put_super(struct super_block *sb)
 771 {
 772         struct ext4_sb_info *sbi = EXT4_SB(sb);
 773         struct ext4_super_block *es = sbi->s_es;
 774         int i, err;
 775
 776         ext4_unregister_li_request(sb);
 777         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 778
 779         flush_workqueue(sbi->rsv_conversion_wq);
 780         destroy_workqueue(sbi->rsv_conversion_wq);
 781
 782         if (sbi->s_journal) {
 783                 err = jbd2_journal_destroy(sbi->s_journal);
 784                 sbi->s_journal = NULL;
 785                 if (err < 0)
 786                         ext4_abort(sb, "Couldn't clean up the journal");
 787         }
 788
 789         ext4_es_unregister_shrinker(sbi);
 790         del_timer_sync(&sbi->s_err_report);
 791         ext4_release_system_zone(sb);
 792         ext4_mb_release(sb);
 793         ext4_ext_release(sb);
 794         ext4_xattr_put_super(sb);
 795
 796         if (!(sb->s_flags & MS_RDONLY)) {
 797                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 798                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 799         }
 800         if (!(sb->s_flags & MS_RDONLY))
 801                 ext4_commit_super(sb, 1);
 802
 803         if (sbi->s_proc) {
 804                 remove_proc_entry("options", sbi->s_proc);
 805                 remove_proc_entry(sb->s_id, ext4_proc_root);
 806         }
 807         kobject_del(&sbi->s_kobj);
 808
 809         for (i = 0; i < sbi->s_gdb_count; i++)
 810                 brelse(sbi->s_group_desc[i]);
 811         kvfree(sbi->s_group_desc);
 812         kvfree(sbi->s_flex_groups);
 813         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 814         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 815         percpu_counter_destroy(&sbi->s_dirs_counter);
 816         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 817         brelse(sbi->s_sbh);
 818 #ifdef CONFIG_QUOTA
 819         for (i = 0; i < EXT4_MAXQUOTAS; i++)
 820                 kfree(sbi->s_qf_names[i]);
 821 #endif
 822
 823         /* Debugging code just in case the in-memory inode orphan list
 824          * isn't empty.  The on-disk one can be non-empty if we've
 825          * detected an error and taken the fs readonly, but the
 826          * in-memory list had better be clean by this point. */
 827         if (!list_empty(&sbi->s_orphan))
 828                 dump_orphan_list(sb, sbi);
 829         J_ASSERT(list_empty(&sbi->s_orphan));
 830
 831         sync_blockdev(sb->s_bdev);
 832         invalidate_bdev(sb->s_bdev);
 833         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 834                 /*
 835                  * Invalidate the journal device's buffers.  We don't want them
 836                  * floating about in memory - the physical journal device may
 837                  * hotswapped, and it breaks the `ro-after' testing code.
 838                  */
 839                 sync_blockdev(sbi->journal_bdev);
 840                 invalidate_bdev(sbi->journal_bdev);
 841                 ext4_blkdev_remove(sbi);
 842         }
 843         if (sbi->s_mb_cache) {
 844                 ext4_xattr_destroy_cache(sbi->s_mb_cache);
 845                 sbi->s_mb_cache = NULL;
 846         }
 847         if (sbi->s_mmp_tsk)
 848                 kthread_stop(sbi->s_mmp_tsk);
 849         sb->s_fs_info = NULL;
 850         /*
 851          * Now that we are completely done shutting down the
 852          * superblock, we need to actually destroy the kobject.
 853          */
 854         kobject_put(&sbi->s_kobj);
 855         wait_for_completion(&sbi->s_kobj_unregister);
 856         if (sbi->s_chksum_driver)
 857                 crypto_free_shash(sbi->s_chksum_driver);
 858         kfree(sbi->s_blockgroup_lock);
 859         kfree(sbi);
 860 }
 861
 862 static struct kmem_cache *ext4_inode_cachep;
 863
 864 /*
 865  * Called inside transaction, so use GFP_NOFS
 866  */
 867 static struct inode *ext4_alloc_inode(struct super_block *sb)
 868 {
 869         struct ext4_inode_info *ei;
 870
 871         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 872         if (!ei)
 873                 return NULL;
 874
 875         ei->vfs_inode.i_version = 1;
 876         spin_lock_init(&ei->i_raw_lock);
 877         INIT_LIST_HEAD(&ei->i_prealloc_list);
 878         spin_lock_init(&ei->i_prealloc_lock);
 879         ext4_es_init_tree(&ei->i_es_tree);
 880         rwlock_init(&ei->i_es_lock);
 881         INIT_LIST_HEAD(&ei->i_es_list);
 882         ei->i_es_all_nr = 0;
 883         ei->i_es_shk_nr = 0;
 884         ei->i_es_shrink_lblk = 0;
 885         ei->i_reserved_data_blocks = 0;
 886         ei->i_reserved_meta_blocks = 0;
 887         ei->i_allocated_meta_blocks = 0;
 888         ei->i_da_metadata_calc_len = 0;
 889         ei->i_da_metadata_calc_last_lblock = 0;
 890         spin_lock_init(&(ei->i_block_reservation_lock));
 891 #ifdef CONFIG_QUOTA
 892         ei->i_reserved_quota = 0;
 893         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
 894 #endif
 895         ei->jinode = NULL;
 896         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
 897         spin_lock_init(&ei->i_completed_io_lock);
 898         ei->i_sync_tid = 0;
 899         ei->i_datasync_tid = 0;
 900         atomic_set(&ei->i_ioend_count, 0);
 901         atomic_set(&ei->i_unwritten, 0);
 902         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
 903 #ifdef CONFIG_EXT4_FS_ENCRYPTION
 904         ei->i_crypt_info = NULL;
 905 #endif
 906         return &ei->vfs_inode;
 907 }
 908
 909 static int ext4_drop_inode(struct inode *inode)
 910 {
 911         int drop = generic_drop_inode(inode);
 912
 913         trace_ext4_drop_inode(inode, drop);
 914         return drop;
 915 }
 916
 917 static void ext4_i_callback(struct rcu_head *head)
 918 {
 919         struct inode *inode = container_of(head, struct inode, i_rcu);
 920         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 921 }
 922
 923 static void ext4_destroy_inode(struct inode *inode)
 924 {
 925         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 926                 ext4_msg(inode->i_sb, KERN_ERR,
 927                          "Inode %lu (%p): orphan list check failed!",
 928                          inode->i_ino, EXT4_I(inode));
 929                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 930                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 931                                 true);
 932                 dump_stack();
 933         }
 934         call_rcu(&inode->i_rcu, ext4_i_callback);
 935 }
 936
 937 static void init_once(void *foo)
 938 {
 939         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 940
 941         INIT_LIST_HEAD(&ei->i_orphan);
 942         init_rwsem(&ei->xattr_sem);
 943         init_rwsem(&ei->i_data_sem);
 944         inode_init_once(&ei->vfs_inode);
 945 }
 946
 947 static int __init init_inodecache(void)
 948 {
 949         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 950                                              sizeof(struct ext4_inode_info),
 951                                              0, (SLAB_RECLAIM_ACCOUNT|
 952                                                 SLAB_MEM_SPREAD),
 953                                              init_once);
 954         if (ext4_inode_cachep == NULL)
 955                 return -ENOMEM;
 956         return 0;
 957 }
 958
 959 static void destroy_inodecache(void)
 960 {
 961         /*
 962          * Make sure all delayed rcu free inodes are flushed before we
 963          * destroy cache.
 964          */
 965         rcu_barrier();
 966         kmem_cache_destroy(ext4_inode_cachep);
 967 }
 968
 969 void ext4_clear_inode(struct inode *inode)
 970 {
 971         invalidate_inode_buffers(inode);
 972         clear_inode(inode);
 973         dquot_drop(inode);
 974         ext4_discard_preallocations(inode);
 975         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
 976         if (EXT4_I(inode)->jinode) {
 977                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
 978                                                EXT4_I(inode)->jinode);
 979                 jbd2_free_inode(EXT4_I(inode)->jinode);
 980                 EXT4_I(inode)->jinode = NULL;
 981         }
 982 #ifdef CONFIG_EXT4_FS_ENCRYPTION
 983         if (EXT4_I(inode)->i_crypt_info)
 984                 ext4_free_encryption_info(inode, EXT4_I(inode)->i_crypt_info);
 985 #endif
 986 }
 987
 988 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 989                                         u64 ino, u32 generation)
 990 {
 991         struct inode *inode;
 992
 993         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 994                 return ERR_PTR(-ESTALE);
 995         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 996                 return ERR_PTR(-ESTALE);
 997
 998         /* iget isn't really right if the inode is currently unallocated!!
 999          *
1000          * ext4_read_inode will return a bad_inode if the inode had been
1001          * deleted, so we should be safe.
1002          *
1003          * Currently we don't know the generation for parent directory, so
1004          * a generation of 0 means "accept any"
1005          */
1006         inode = ext4_iget_normal(sb, ino);
1007         if (IS_ERR(inode))
1008                 return ERR_CAST(inode);
1009         if (generation && inode->i_generation != generation) {
1010                 iput(inode);
1011                 return ERR_PTR(-ESTALE);
1012         }
1013
1014         return inode;
1015 }
1016
1017 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1018                                         int fh_len, int fh_type)
1019 {
1020         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1021                                     ext4_nfs_get_inode);
1022 }
1023
1024 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1025                                         int fh_len, int fh_type)
1026 {
1027         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1028                                     ext4_nfs_get_inode);
1029 }
1030
1031 /*
1032  * Try to release metadata pages (indirect blocks, directories) which are
1033  * mapped via the block device.  Since these pages could have journal heads
1034  * which would prevent try_to_free_buffers() from freeing them, we must use
1035  * jbd2 layer's try_to_free_buffers() function to release them.
1036  */
1037 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1038                                  gfp_t wait)
1039 {
1040         journal_t *journal = EXT4_SB(sb)->s_journal;
1041
1042         WARN_ON(PageChecked(page));
1043         if (!page_has_buffers(page))
1044                 return 0;
1045         if (journal)
1046                 return jbd2_journal_try_to_free_buffers(journal, page,
1047                                                         wait & ~__GFP_WAIT);
1048         return try_to_free_buffers(page);
1049 }
1050
1051 #ifdef CONFIG_QUOTA
1052 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1053 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1054
1055 static int ext4_write_dquot(struct dquot *dquot);
1056 static int ext4_acquire_dquot(struct dquot *dquot);
1057 static int ext4_release_dquot(struct dquot *dquot);
1058 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1059 static int ext4_write_info(struct super_block *sb, int type);
1060 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1061                          struct path *path);
1062 static int ext4_quota_off(struct super_block *sb, int type);
1063 static int ext4_quota_on_mount(struct super_block *sb, int type);
1064 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1065                                size_t len, loff_t off);
1066 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1067                                 const char *data, size_t len, loff_t off);
1068 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1069                              unsigned int flags);
1070 static int ext4_enable_quotas(struct super_block *sb);
1071
1072 static struct dquot **ext4_get_dquots(struct inode *inode)
1073 {
1074         return EXT4_I(inode)->i_dquot;
1075 }
1076
1077 static const struct dquot_operations ext4_quota_operations = {
1078         .get_reserved_space = ext4_get_reserved_space,
1079         .write_dquot    = ext4_write_dquot,
1080         .acquire_dquot  = ext4_acquire_dquot,
1081         .release_dquot  = ext4_release_dquot,
1082         .mark_dirty     = ext4_mark_dquot_dirty,
1083         .write_info     = ext4_write_info,
1084         .alloc_dquot    = dquot_alloc,
1085         .destroy_dquot  = dquot_destroy,
1086 };
1087
1088 static const struct quotactl_ops ext4_qctl_operations = {
1089         .quota_on       = ext4_quota_on,
1090         .quota_off      = ext4_quota_off,
1091         .quota_sync     = dquot_quota_sync,
1092         .get_state      = dquot_get_state,
1093         .set_info       = dquot_set_dqinfo,
1094         .get_dqblk      = dquot_get_dqblk,
1095         .set_dqblk      = dquot_set_dqblk
1096 };
1097 #endif
1098
1099 static const struct super_operations ext4_sops = {
1100         .alloc_inode    = ext4_alloc_inode,
1101         .destroy_inode  = ext4_destroy_inode,
1102         .write_inode    = ext4_write_inode,
1103         .dirty_inode    = ext4_dirty_inode,
1104         .drop_inode     = ext4_drop_inode,
1105         .evict_inode    = ext4_evict_inode,
1106         .put_super      = ext4_put_super,
1107         .sync_fs        = ext4_sync_fs,
1108         .freeze_fs      = ext4_freeze,
1109         .unfreeze_fs    = ext4_unfreeze,
1110         .statfs         = ext4_statfs,
1111         .remount_fs     = ext4_remount,
1112         .show_options   = ext4_show_options,
1113 #ifdef CONFIG_QUOTA
1114         .quota_read     = ext4_quota_read,
1115         .quota_write    = ext4_quota_write,
1116         .get_dquots     = ext4_get_dquots,
1117 #endif
1118         .bdev_try_to_free_page = bdev_try_to_free_page,
1119 };
1120
1121 static const struct export_operations ext4_export_ops = {
1122         .fh_to_dentry = ext4_fh_to_dentry,
1123         .fh_to_parent = ext4_fh_to_parent,
1124         .get_parent = ext4_get_parent,
1125 };
1126
1127 enum {
1128         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1129         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1130         Opt_nouid32, Opt_debug, Opt_removed,
1131         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1132         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1133         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1134         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1135         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1136         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1137         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1138         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1139         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1140         Opt_usrquota, Opt_grpquota, Opt_i_version, Opt_dax,
1141         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1142         Opt_lazytime, Opt_nolazytime,
1143         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1144         Opt_inode_readahead_blks, Opt_journal_ioprio,
1145         Opt_dioread_nolock, Opt_dioread_lock,
1146         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1147         Opt_max_dir_size_kb, Opt_nojournal_checksum,
1148 };
1149
1150 static const match_table_t tokens = {
1151         {Opt_bsd_df, "bsddf"},
1152         {Opt_minix_df, "minixdf"},
1153         {Opt_grpid, "grpid"},
1154         {Opt_grpid, "bsdgroups"},
1155         {Opt_nogrpid, "nogrpid"},
1156         {Opt_nogrpid, "sysvgroups"},
1157         {Opt_resgid, "resgid=%u"},
1158         {Opt_resuid, "resuid=%u"},
1159         {Opt_sb, "sb=%u"},
1160         {Opt_err_cont, "errors=continue"},
1161         {Opt_err_panic, "errors=panic"},
1162         {Opt_err_ro, "errors=remount-ro"},
1163         {Opt_nouid32, "nouid32"},
1164         {Opt_debug, "debug"},
1165         {Opt_removed, "oldalloc"},
1166         {Opt_removed, "orlov"},
1167         {Opt_user_xattr, "user_xattr"},
1168         {Opt_nouser_xattr, "nouser_xattr"},
1169         {Opt_acl, "acl"},
1170         {Opt_noacl, "noacl"},
1171         {Opt_noload, "norecovery"},
1172         {Opt_noload, "noload"},
1173         {Opt_removed, "nobh"},
1174         {Opt_removed, "bh"},
1175         {Opt_commit, "commit=%u"},
1176         {Opt_min_batch_time, "min_batch_time=%u"},
1177         {Opt_max_batch_time, "max_batch_time=%u"},
1178         {Opt_journal_dev, "journal_dev=%u"},
1179         {Opt_journal_path, "journal_path=%s"},
1180         {Opt_journal_checksum, "journal_checksum"},
1181         {Opt_nojournal_checksum, "nojournal_checksum"},
1182         {Opt_journal_async_commit, "journal_async_commit"},
1183         {Opt_abort, "abort"},
1184         {Opt_data_journal, "data=journal"},
1185         {Opt_data_ordered, "data=ordered"},
1186         {Opt_data_writeback, "data=writeback"},
1187         {Opt_data_err_abort, "data_err=abort"},
1188         {Opt_data_err_ignore, "data_err=ignore"},
1189         {Opt_offusrjquota, "usrjquota="},
1190         {Opt_usrjquota, "usrjquota=%s"},
1191         {Opt_offgrpjquota, "grpjquota="},
1192         {Opt_grpjquota, "grpjquota=%s"},
1193         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1194         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1195         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1196         {Opt_grpquota, "grpquota"},
1197         {Opt_noquota, "noquota"},
1198         {Opt_quota, "quota"},
1199         {Opt_usrquota, "usrquota"},
1200         {Opt_barrier, "barrier=%u"},
1201         {Opt_barrier, "barrier"},
1202         {Opt_nobarrier, "nobarrier"},
1203         {Opt_i_version, "i_version"},
1204         {Opt_dax, "dax"},
1205         {Opt_stripe, "stripe=%u"},
1206         {Opt_delalloc, "delalloc"},
1207         {Opt_lazytime, "lazytime"},
1208         {Opt_nolazytime, "nolazytime"},
1209         {Opt_nodelalloc, "nodelalloc"},
1210         {Opt_removed, "mblk_io_submit"},
1211         {Opt_removed, "nomblk_io_submit"},
1212         {Opt_block_validity, "block_validity"},
1213         {Opt_noblock_validity, "noblock_validity"},
1214         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1215         {Opt_journal_ioprio, "journal_ioprio=%u"},
1216         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1217         {Opt_auto_da_alloc, "auto_da_alloc"},
1218         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1219         {Opt_dioread_nolock, "dioread_nolock"},
1220         {Opt_dioread_lock, "dioread_lock"},
1221         {Opt_discard, "discard"},
1222         {Opt_nodiscard, "nodiscard"},
1223         {Opt_init_itable, "init_itable=%u"},
1224         {Opt_init_itable, "init_itable"},
1225         {Opt_noinit_itable, "noinit_itable"},
1226         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1227         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1228         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1229         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1230         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1231         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1232         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1233         {Opt_err, NULL},
1234 };
1235
1236 static ext4_fsblk_t get_sb_block(void **data)
1237 {
1238         ext4_fsblk_t    sb_block;
1239         char            *options = (char *) *data;
1240
1241         if (!options || strncmp(options, "sb=", 3) != 0)
1242                 return 1;       /* Default location */
1243
1244         options += 3;
1245         /* TODO: use simple_strtoll with >32bit ext4 */
1246         sb_block = simple_strtoul(options, &options, 0);
1247         if (*options && *options != ',') {
1248                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1249                        (char *) *data);
1250                 return 1;
1251         }
1252         if (*options == ',')
1253                 options++;
1254         *data = (void *) options;
1255
1256         return sb_block;
1257 }
1258
1259 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1260 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1261         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1262
1263 #ifdef CONFIG_QUOTA
1264 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1265 {
1266         struct ext4_sb_info *sbi = EXT4_SB(sb);
1267         char *qname;
1268         int ret = -1;
1269
1270         if (sb_any_quota_loaded(sb) &&
1271                 !sbi->s_qf_names[qtype]) {
1272                 ext4_msg(sb, KERN_ERR,
1273                         "Cannot change journaled "
1274                         "quota options when quota turned on");
1275                 return -1;
1276         }
1277         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1278                 ext4_msg(sb, KERN_ERR, "Cannot set journaled quota options "
1279                          "when QUOTA feature is enabled");
1280                 return -1;
1281         }
1282         qname = match_strdup(args);
1283         if (!qname) {
1284                 ext4_msg(sb, KERN_ERR,
1285                         "Not enough memory for storing quotafile name");
1286                 return -1;
1287         }
1288         if (sbi->s_qf_names[qtype]) {
1289                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1290                         ret = 1;
1291                 else
1292                         ext4_msg(sb, KERN_ERR,
1293                                  "%s quota file already specified",
1294                                  QTYPE2NAME(qtype));
1295                 goto errout;
1296         }
1297         if (strchr(qname, '/')) {
1298                 ext4_msg(sb, KERN_ERR,
1299                         "quotafile must be on filesystem root");
1300                 goto errout;
1301         }
1302         sbi->s_qf_names[qtype] = qname;
1303         set_opt(sb, QUOTA);
1304         return 1;
1305 errout:
1306         kfree(qname);
1307         return ret;
1308 }
1309
1310 static int clear_qf_name(struct super_block *sb, int qtype)
1311 {
1312
1313         struct ext4_sb_info *sbi = EXT4_SB(sb);
1314
1315         if (sb_any_quota_loaded(sb) &&
1316                 sbi->s_qf_names[qtype]) {
1317                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1318                         " when quota turned on");
1319                 return -1;
1320         }
1321         kfree(sbi->s_qf_names[qtype]);
1322         sbi->s_qf_names[qtype] = NULL;
1323         return 1;
1324 }
1325 #endif
1326
1327 #define MOPT_SET        0x0001
1328 #define MOPT_CLEAR      0x0002
1329 #define MOPT_NOSUPPORT  0x0004
1330 #define MOPT_EXPLICIT   0x0008
1331 #define MOPT_CLEAR_ERR  0x0010
1332 #define MOPT_GTE0       0x0020
1333 #ifdef CONFIG_QUOTA
1334 #define MOPT_Q          0
1335 #define MOPT_QFMT       0x0040
1336 #else
1337 #define MOPT_Q          MOPT_NOSUPPORT
1338 #define MOPT_QFMT       MOPT_NOSUPPORT
1339 #endif
1340 #define MOPT_DATAJ      0x0080
1341 #define MOPT_NO_EXT2    0x0100
1342 #define MOPT_NO_EXT3    0x0200
1343 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1344 #define MOPT_STRING     0x0400
1345
1346 static const struct mount_opts {
1347         int     token;
1348         int     mount_opt;
1349         int     flags;
1350 } ext4_mount_opts[] = {
1351         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1352         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1353         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1354         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1355         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1356         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1357         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1358          MOPT_EXT4_ONLY | MOPT_SET},
1359         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1360          MOPT_EXT4_ONLY | MOPT_CLEAR},
1361         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1362         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1363         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1364          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1365         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1366          MOPT_EXT4_ONLY | MOPT_CLEAR},
1367         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1368          MOPT_EXT4_ONLY | MOPT_CLEAR},
1369         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1370          MOPT_EXT4_ONLY | MOPT_SET},
1371         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1372                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1373          MOPT_EXT4_ONLY | MOPT_SET},
1374         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1375         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1376         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1377         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1378         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1379          MOPT_NO_EXT2 | MOPT_SET},
1380         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1381          MOPT_NO_EXT2 | MOPT_CLEAR},
1382         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1383         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1384         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1385         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1386         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1387         {Opt_commit, 0, MOPT_GTE0},
1388         {Opt_max_batch_time, 0, MOPT_GTE0},
1389         {Opt_min_batch_time, 0, MOPT_GTE0},
1390         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1391         {Opt_init_itable, 0, MOPT_GTE0},
1392         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1393         {Opt_stripe, 0, MOPT_GTE0},
1394         {Opt_resuid, 0, MOPT_GTE0},
1395         {Opt_resgid, 0, MOPT_GTE0},
1396         {Opt_journal_dev, 0, MOPT_GTE0},
1397         {Opt_journal_path, 0, MOPT_STRING},
1398         {Opt_journal_ioprio, 0, MOPT_GTE0},
1399         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1400         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1401         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1402          MOPT_NO_EXT2 | MOPT_DATAJ},
1403         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1404         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1405 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1406         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1407         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1408 #else
1409         {Opt_acl, 0, MOPT_NOSUPPORT},
1410         {Opt_noacl, 0, MOPT_NOSUPPORT},
1411 #endif
1412         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1413         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1414         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1415         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1416                                                         MOPT_SET | MOPT_Q},
1417         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1418                                                         MOPT_SET | MOPT_Q},
1419         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1420                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1421         {Opt_usrjquota, 0, MOPT_Q},
1422         {Opt_grpjquota, 0, MOPT_Q},
1423         {Opt_offusrjquota, 0, MOPT_Q},
1424         {Opt_offgrpjquota, 0, MOPT_Q},
1425         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1426         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1427         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1428         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1429         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1430         {Opt_err, 0, 0}
1431 };
1432
1433 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1434                             substring_t *args, unsigned long *journal_devnum,
1435                             unsigned int *journal_ioprio, int is_remount)
1436 {
1437         struct ext4_sb_info *sbi = EXT4_SB(sb);
1438         const struct mount_opts *m;
1439         kuid_t uid;
1440         kgid_t gid;
1441         int arg = 0;
1442
1443 #ifdef CONFIG_QUOTA
1444         if (token == Opt_usrjquota)
1445                 return set_qf_name(sb, USRQUOTA, &args[0]);
1446         else if (token == Opt_grpjquota)
1447                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1448         else if (token == Opt_offusrjquota)
1449                 return clear_qf_name(sb, USRQUOTA);
1450         else if (token == Opt_offgrpjquota)
1451                 return clear_qf_name(sb, GRPQUOTA);
1452 #endif
1453         switch (token) {
1454         case Opt_noacl:
1455         case Opt_nouser_xattr:
1456                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1457                 break;
1458         case Opt_sb:
1459                 return 1;       /* handled by get_sb_block() */
1460         case Opt_removed:
1461                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1462                 return 1;
1463         case Opt_abort:
1464                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1465                 return 1;
1466         case Opt_i_version:
1467                 sb->s_flags |= MS_I_VERSION;
1468                 return 1;
1469         case Opt_lazytime:
1470                 sb->s_flags |= MS_LAZYTIME;
1471                 return 1;
1472         case Opt_nolazytime:
1473                 sb->s_flags &= ~MS_LAZYTIME;
1474                 return 1;
1475         }
1476
1477         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1478                 if (token == m->token)
1479                         break;
1480
1481         if (m->token == Opt_err) {
1482                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1483                          "or missing value", opt);
1484                 return -1;
1485         }
1486
1487         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1488                 ext4_msg(sb, KERN_ERR,
1489                          "Mount option \"%s\" incompatible with ext2", opt);
1490                 return -1;
1491         }
1492         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1493                 ext4_msg(sb, KERN_ERR,
1494                          "Mount option \"%s\" incompatible with ext3", opt);
1495                 return -1;
1496         }
1497
1498         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1499                 return -1;
1500         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1501                 return -1;
1502         if (m->flags & MOPT_EXPLICIT)
1503                 set_opt2(sb, EXPLICIT_DELALLOC);
1504         if (m->flags & MOPT_CLEAR_ERR)
1505                 clear_opt(sb, ERRORS_MASK);
1506         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1507                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1508                          "options when quota turned on");
1509                 return -1;
1510         }
1511
1512         if (m->flags & MOPT_NOSUPPORT) {
1513                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1514         } else if (token == Opt_commit) {
1515                 if (arg == 0)
1516                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1517                 sbi->s_commit_interval = HZ * arg;
1518         } else if (token == Opt_max_batch_time) {
1519                 sbi->s_max_batch_time = arg;
1520         } else if (token == Opt_min_batch_time) {
1521                 sbi->s_min_batch_time = arg;
1522         } else if (token == Opt_inode_readahead_blks) {
1523                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1524                         ext4_msg(sb, KERN_ERR,
1525                                  "EXT4-fs: inode_readahead_blks must be "
1526                                  "0 or a power of 2 smaller than 2^31");
1527                         return -1;
1528                 }
1529                 sbi->s_inode_readahead_blks = arg;
1530         } else if (token == Opt_init_itable) {
1531                 set_opt(sb, INIT_INODE_TABLE);
1532                 if (!args->from)
1533                         arg = EXT4_DEF_LI_WAIT_MULT;
1534                 sbi->s_li_wait_mult = arg;
1535         } else if (token == Opt_max_dir_size_kb) {
1536                 sbi->s_max_dir_size_kb = arg;
1537         } else if (token == Opt_stripe) {
1538                 sbi->s_stripe = arg;
1539         } else if (token == Opt_resuid) {
1540                 uid = make_kuid(current_user_ns(), arg);
1541                 if (!uid_valid(uid)) {
1542                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1543                         return -1;
1544                 }
1545                 sbi->s_resuid = uid;
1546         } else if (token == Opt_resgid) {
1547                 gid = make_kgid(current_user_ns(), arg);
1548                 if (!gid_valid(gid)) {
1549                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1550                         return -1;
1551                 }
1552                 sbi->s_resgid = gid;
1553         } else if (token == Opt_journal_dev) {
1554                 if (is_remount) {
1555                         ext4_msg(sb, KERN_ERR,
1556                                  "Cannot specify journal on remount");
1557                         return -1;
1558                 }
1559                 *journal_devnum = arg;
1560         } else if (token == Opt_journal_path) {
1561                 char *journal_path;
1562                 struct inode *journal_inode;
1563                 struct path path;
1564                 int error;
1565
1566                 if (is_remount) {
1567                         ext4_msg(sb, KERN_ERR,
1568                                  "Cannot specify journal on remount");
1569                         return -1;
1570                 }
1571                 journal_path = match_strdup(&args[0]);
1572                 if (!journal_path) {
1573                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1574                                 "journal device string");
1575                         return -1;
1576                 }
1577
1578                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1579                 if (error) {
1580                         ext4_msg(sb, KERN_ERR, "error: could not find "
1581                                 "journal device path: error %d", error);
1582                         kfree(journal_path);
1583                         return -1;
1584                 }
1585
1586                 journal_inode = d_inode(path.dentry);
1587                 if (!S_ISBLK(journal_inode->i_mode)) {
1588                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1589                                 "is not a block device", journal_path);
1590                         path_put(&path);
1591                         kfree(journal_path);
1592                         return -1;
1593                 }
1594
1595                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1596                 path_put(&path);
1597                 kfree(journal_path);
1598         } else if (token == Opt_journal_ioprio) {
1599                 if (arg > 7) {
1600                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1601                                  " (must be 0-7)");
1602                         return -1;
1603                 }
1604                 *journal_ioprio =
1605                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1606         } else if (token == Opt_test_dummy_encryption) {
1607 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1608                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1609                 ext4_msg(sb, KERN_WARNING,
1610                          "Test dummy encryption mode enabled");
1611 #else
1612                 ext4_msg(sb, KERN_WARNING,
1613                          "Test dummy encryption mount option ignored");
1614 #endif
1615         } else if (m->flags & MOPT_DATAJ) {
1616                 if (is_remount) {
1617                         if (!sbi->s_journal)
1618                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1619                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1620                                 ext4_msg(sb, KERN_ERR,
1621                                          "Cannot change data mode on remount");
1622                                 return -1;
1623                         }
1624                 } else {
1625                         clear_opt(sb, DATA_FLAGS);
1626                         sbi->s_mount_opt |= m->mount_opt;
1627                 }
1628 #ifdef CONFIG_QUOTA
1629         } else if (m->flags & MOPT_QFMT) {
1630                 if (sb_any_quota_loaded(sb) &&
1631                     sbi->s_jquota_fmt != m->mount_opt) {
1632                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1633                                  "quota options when quota turned on");
1634                         return -1;
1635                 }
1636                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
1637                                                EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1638                         ext4_msg(sb, KERN_ERR,
1639                                  "Cannot set journaled quota options "
1640                                  "when QUOTA feature is enabled");
1641                         return -1;
1642                 }
1643                 sbi->s_jquota_fmt = m->mount_opt;
1644 #endif
1645 #ifndef CONFIG_FS_DAX
1646         } else if (token == Opt_dax) {
1647                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1648                 return -1;
1649 #endif
1650         } else {
1651                 if (!args->from)
1652                         arg = 1;
1653                 if (m->flags & MOPT_CLEAR)
1654                         arg = !arg;
1655                 else if (unlikely(!(m->flags & MOPT_SET))) {
1656                         ext4_msg(sb, KERN_WARNING,
1657                                  "buggy handling of option %s", opt);
1658                         WARN_ON(1);
1659                         return -1;
1660                 }
1661                 if (arg != 0)
1662                         sbi->s_mount_opt |= m->mount_opt;
1663                 else
1664                         sbi->s_mount_opt &= ~m->mount_opt;
1665         }
1666         return 1;
1667 }
1668
1669 static int parse_options(char *options, struct super_block *sb,
1670                          unsigned long *journal_devnum,
1671                          unsigned int *journal_ioprio,
1672                          int is_remount)
1673 {
1674         struct ext4_sb_info *sbi = EXT4_SB(sb);
1675         char *p;
1676         substring_t args[MAX_OPT_ARGS];
1677         int token;
1678
1679         if (!options)
1680                 return 1;
1681
1682         while ((p = strsep(&options, ",")) != NULL) {
1683                 if (!*p)
1684                         continue;
1685                 /*
1686                  * Initialize args struct so we know whether arg was
1687                  * found; some options take optional arguments.
1688                  */
1689                 args[0].to = args[0].from = NULL;
1690                 token = match_token(p, tokens, args);
1691                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1692                                      journal_ioprio, is_remount) < 0)
1693                         return 0;
1694         }
1695 #ifdef CONFIG_QUOTA
1696         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
1697             (test_opt(sb, USRQUOTA) || test_opt(sb, GRPQUOTA))) {
1698                 ext4_msg(sb, KERN_ERR, "Cannot set quota options when QUOTA "
1699                          "feature is enabled");
1700                 return 0;
1701         }
1702         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1703                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1704                         clear_opt(sb, USRQUOTA);
1705
1706                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1707                         clear_opt(sb, GRPQUOTA);
1708
1709                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1710                         ext4_msg(sb, KERN_ERR, "old and new quota "
1711                                         "format mixing");
1712                         return 0;
1713                 }
1714
1715                 if (!sbi->s_jquota_fmt) {
1716                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1717                                         "not specified");
1718                         return 0;
1719                 }
1720         }
1721 #endif
1722         if (test_opt(sb, DIOREAD_NOLOCK)) {
1723                 int blocksize =
1724                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1725
1726                 if (blocksize < PAGE_CACHE_SIZE) {
1727                         ext4_msg(sb, KERN_ERR, "can't mount with "
1728                                  "dioread_nolock if block size != PAGE_SIZE");
1729                         return 0;
1730                 }
1731         }
1732         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
1733             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
1734                 ext4_msg(sb, KERN_ERR, "can't mount with journal_async_commit "
1735                          "in data=ordered mode");
1736                 return 0;
1737         }
1738         return 1;
1739 }
1740
1741 static inline void ext4_show_quota_options(struct seq_file *seq,
1742                                            struct super_block *sb)
1743 {
1744 #if defined(CONFIG_QUOTA)
1745         struct ext4_sb_info *sbi = EXT4_SB(sb);
1746
1747         if (sbi->s_jquota_fmt) {
1748                 char *fmtname = "";
1749
1750                 switch (sbi->s_jquota_fmt) {
1751                 case QFMT_VFS_OLD:
1752                         fmtname = "vfsold";
1753                         break;
1754                 case QFMT_VFS_V0:
1755                         fmtname = "vfsv0";
1756                         break;
1757                 case QFMT_VFS_V1:
1758                         fmtname = "vfsv1";
1759                         break;
1760                 }
1761                 seq_printf(seq, ",jqfmt=%s", fmtname);
1762         }
1763
1764         if (sbi->s_qf_names[USRQUOTA])
1765                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1766
1767         if (sbi->s_qf_names[GRPQUOTA])
1768                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1769 #endif
1770 }
1771
1772 static const char *token2str(int token)
1773 {
1774         const struct match_token *t;
1775
1776         for (t = tokens; t->token != Opt_err; t++)
1777                 if (t->token == token && !strchr(t->pattern, '='))
1778                         break;
1779         return t->pattern;
1780 }
1781
1782 /*
1783  * Show an option if
1784  *  - it's set to a non-default value OR
1785  *  - if the per-sb default is different from the global default
1786  */
1787 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1788                               int nodefs)
1789 {
1790         struct ext4_sb_info *sbi = EXT4_SB(sb);
1791         struct ext4_super_block *es = sbi->s_es;
1792         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1793         const struct mount_opts *m;
1794         char sep = nodefs ? '\n' : ',';
1795
1796 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1797 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1798
1799         if (sbi->s_sb_block != 1)
1800                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1801
1802         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1803                 int want_set = m->flags & MOPT_SET;
1804                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1805                     (m->flags & MOPT_CLEAR_ERR))
1806                         continue;
1807                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1808                         continue; /* skip if same as the default */
1809                 if ((want_set &&
1810                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1811                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1812                         continue; /* select Opt_noFoo vs Opt_Foo */
1813                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1814         }
1815
1816         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1817             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1818                 SEQ_OPTS_PRINT("resuid=%u",
1819                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1820         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1821             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1822                 SEQ_OPTS_PRINT("resgid=%u",
1823                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1824         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1825         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1826                 SEQ_OPTS_PUTS("errors=remount-ro");
1827         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1828                 SEQ_OPTS_PUTS("errors=continue");
1829         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1830                 SEQ_OPTS_PUTS("errors=panic");
1831         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1832                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1833         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1834                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1835         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1836                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1837         if (sb->s_flags & MS_I_VERSION)
1838                 SEQ_OPTS_PUTS("i_version");
1839         if (nodefs || sbi->s_stripe)
1840                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1841         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1842                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1843                         SEQ_OPTS_PUTS("data=journal");
1844                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1845                         SEQ_OPTS_PUTS("data=ordered");
1846                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1847                         SEQ_OPTS_PUTS("data=writeback");
1848         }
1849         if (nodefs ||
1850             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1851                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1852                                sbi->s_inode_readahead_blks);
1853
1854         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1855                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1856                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1857         if (nodefs || sbi->s_max_dir_size_kb)
1858                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
1859
1860         ext4_show_quota_options(seq, sb);
1861         return 0;
1862 }
1863
1864 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1865 {
1866         return _ext4_show_options(seq, root->d_sb, 0);
1867 }
1868
1869 static int options_seq_show(struct seq_file *seq, void *offset)
1870 {
1871         struct super_block *sb = seq->private;
1872         int rc;
1873
1874         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1875         rc = _ext4_show_options(seq, sb, 1);
1876         seq_puts(seq, "\n");
1877         return rc;
1878 }
1879
1880 static int options_open_fs(struct inode *inode, struct file *file)
1881 {
1882         return single_open(file, options_seq_show, PDE_DATA(inode));
1883 }
1884
1885 static const struct file_operations ext4_seq_options_fops = {
1886         .owner = THIS_MODULE,
1887         .open = options_open_fs,
1888         .read = seq_read,
1889         .llseek = seq_lseek,
1890         .release = single_release,
1891 };
1892
1893 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1894                             int read_only)
1895 {
1896         struct ext4_sb_info *sbi = EXT4_SB(sb);
1897         int res = 0;
1898
1899         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1900                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1901                          "forcing read-only mode");
1902                 res = MS_RDONLY;
1903         }
1904         if (read_only)
1905                 goto done;
1906         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1907                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1908                          "running e2fsck is recommended");
1909         else if (sbi->s_mount_state & EXT4_ERROR_FS)
1910                 ext4_msg(sb, KERN_WARNING,
1911                          "warning: mounting fs with errors, "
1912                          "running e2fsck is recommended");
1913         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1914                  le16_to_cpu(es->s_mnt_count) >=
1915                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1916                 ext4_msg(sb, KERN_WARNING,
1917                          "warning: maximal mount count reached, "
1918                          "running e2fsck is recommended");
1919         else if (le32_to_cpu(es->s_checkinterval) &&
1920                 (le32_to_cpu(es->s_lastcheck) +
1921                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1922                 ext4_msg(sb, KERN_WARNING,
1923                          "warning: checktime reached, "
1924                          "running e2fsck is recommended");
1925         if (!sbi->s_journal)
1926                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1927         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1928                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1929         le16_add_cpu(&es->s_mnt_count, 1);
1930         es->s_mtime = cpu_to_le32(get_seconds());
1931         ext4_update_dynamic_rev(sb);
1932         if (sbi->s_journal)
1933                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1934
1935         ext4_commit_super(sb, 1);
1936 done:
1937         if (test_opt(sb, DEBUG))
1938                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1939                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1940                         sb->s_blocksize,
1941                         sbi->s_groups_count,
1942                         EXT4_BLOCKS_PER_GROUP(sb),
1943                         EXT4_INODES_PER_GROUP(sb),
1944                         sbi->s_mount_opt, sbi->s_mount_opt2);
1945
1946         cleancache_init_fs(sb);
1947         return res;
1948 }
1949
1950 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
1951 {
1952         struct ext4_sb_info *sbi = EXT4_SB(sb);
1953         struct flex_groups *new_groups;
1954         int size;
1955
1956         if (!sbi->s_log_groups_per_flex)
1957                 return 0;
1958
1959         size = ext4_flex_group(sbi, ngroup - 1) + 1;
1960         if (size <= sbi->s_flex_groups_allocated)
1961                 return 0;
1962
1963         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
1964         new_groups = ext4_kvzalloc(size, GFP_KERNEL);
1965         if (!new_groups) {
1966                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
1967                          size / (int) sizeof(struct flex_groups));
1968                 return -ENOMEM;
1969         }
1970
1971         if (sbi->s_flex_groups) {
1972                 memcpy(new_groups, sbi->s_flex_groups,
1973                        (sbi->s_flex_groups_allocated *
1974                         sizeof(struct flex_groups)));
1975                 kvfree(sbi->s_flex_groups);
1976         }
1977         sbi->s_flex_groups = new_groups;
1978         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
1979         return 0;
1980 }
1981
1982 static int ext4_fill_flex_info(struct super_block *sb)
1983 {
1984         struct ext4_sb_info *sbi = EXT4_SB(sb);
1985         struct ext4_group_desc *gdp = NULL;
1986         ext4_group_t flex_group;
1987         int i, err;
1988
1989         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1990         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1991                 sbi->s_log_groups_per_flex = 0;
1992                 return 1;
1993         }
1994
1995         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
1996         if (err)
1997                 goto failed;
1998
1999         for (i = 0; i < sbi->s_groups_count; i++) {
2000                 gdp = ext4_get_group_desc(sb, i, NULL);
2001
2002                 flex_group = ext4_flex_group(sbi, i);
2003                 atomic_add(ext4_free_inodes_count(sb, gdp),
2004                            &sbi->s_flex_groups[flex_group].free_inodes);
2005                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2006                              &sbi->s_flex_groups[flex_group].free_clusters);
2007                 atomic_add(ext4_used_dirs_count(sb, gdp),
2008                            &sbi->s_flex_groups[flex_group].used_dirs);
2009         }
2010
2011         return 1;
2012 failed:
2013         return 0;
2014 }
2015
2016 static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
2017                                    struct ext4_group_desc *gdp)
2018 {
2019         int offset;
2020         __u16 crc = 0;
2021         __le32 le_group = cpu_to_le32(block_group);
2022
2023         if (ext4_has_metadata_csum(sbi->s_sb)) {
2024                 /* Use new metadata_csum algorithm */
2025                 __le16 save_csum;
2026                 __u32 csum32;
2027
2028                 save_csum = gdp->bg_checksum;
2029                 gdp->bg_checksum = 0;
2030                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2031                                      sizeof(le_group));
2032                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
2033                                      sbi->s_desc_size);
2034                 gdp->bg_checksum = save_csum;
2035
2036                 crc = csum32 & 0xFFFF;
2037                 goto out;
2038         }
2039
2040         /* old crc16 code */
2041         if (!(sbi->s_es->s_feature_ro_compat &
2042               cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)))
2043                 return 0;
2044
2045         offset = offsetof(struct ext4_group_desc, bg_checksum);
2046
2047         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2048         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2049         crc = crc16(crc, (__u8 *)gdp, offset);
2050         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2051         /* for checksum of struct ext4_group_desc do the rest...*/
2052         if ((sbi->s_es->s_feature_incompat &
2053              cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2054             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2055                 crc = crc16(crc, (__u8 *)gdp + offset,
2056                             le16_to_cpu(sbi->s_es->s_desc_size) -
2057                                 offset);
2058
2059 out:
2060         return cpu_to_le16(crc);
2061 }
2062
2063 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2064                                 struct ext4_group_desc *gdp)
2065 {
2066         if (ext4_has_group_desc_csum(sb) &&
2067             (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
2068                                                       block_group, gdp)))
2069                 return 0;
2070
2071         return 1;
2072 }
2073
2074 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2075                               struct ext4_group_desc *gdp)
2076 {
2077         if (!ext4_has_group_desc_csum(sb))
2078                 return;
2079         gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
2080 }
2081
2082 /* Called at mount-time, super-block is locked */
2083 static int ext4_check_descriptors(struct super_block *sb,
2084                                   ext4_group_t *first_not_zeroed)
2085 {
2086         struct ext4_sb_info *sbi = EXT4_SB(sb);
2087         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2088         ext4_fsblk_t last_block;
2089         ext4_fsblk_t block_bitmap;
2090         ext4_fsblk_t inode_bitmap;
2091         ext4_fsblk_t inode_table;
2092         int flexbg_flag = 0;
2093         ext4_group_t i, grp = sbi->s_groups_count;
2094
2095         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2096                 flexbg_flag = 1;
2097
2098         ext4_debug("Checking group descriptors");
2099
2100         for (i = 0; i < sbi->s_groups_count; i++) {
2101                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2102
2103                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2104                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2105                 else
2106                         last_block = first_block +
2107                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2108
2109                 if ((grp == sbi->s_groups_count) &&
2110                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2111                         grp = i;
2112
2113                 block_bitmap = ext4_block_bitmap(sb, gdp);
2114                 if (block_bitmap < first_block || block_bitmap > last_block) {
2115                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2116                                "Block bitmap for group %u not in group "
2117                                "(block %llu)!", i, block_bitmap);
2118                         return 0;
2119                 }
2120                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2121                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2122                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2123                                "Inode bitmap for group %u not in group "
2124                                "(block %llu)!", i, inode_bitmap);
2125                         return 0;
2126                 }
2127                 inode_table = ext4_inode_table(sb, gdp);
2128                 if (inode_table < first_block ||
2129                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2130                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2131                                "Inode table for group %u not in group "
2132                                "(block %llu)!", i, inode_table);
2133                         return 0;
2134                 }
2135                 ext4_lock_group(sb, i);
2136                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2137                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2138                                  "Checksum for group %u failed (%u!=%u)",
2139                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2140                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2141                         if (!(sb->s_flags & MS_RDONLY)) {
2142                                 ext4_unlock_group(sb, i);
2143                                 return 0;
2144                         }
2145                 }
2146                 ext4_unlock_group(sb, i);
2147                 if (!flexbg_flag)
2148                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2149         }
2150         if (NULL != first_not_zeroed)
2151                 *first_not_zeroed = grp;
2152         return 1;
2153 }
2154
2155 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2156  * the superblock) which were deleted from all directories, but held open by
2157  * a process at the time of a crash.  We walk the list and try to delete these
2158  * inodes at recovery time (only with a read-write filesystem).
2159  *
2160  * In order to keep the orphan inode chain consistent during traversal (in
2161  * case of crash during recovery), we link each inode into the superblock
2162  * orphan list_head and handle it the same way as an inode deletion during
2163  * normal operation (which journals the operations for us).
2164  *
2165  * We only do an iget() and an iput() on each inode, which is very safe if we
2166  * accidentally point at an in-use or already deleted inode.  The worst that
2167  * can happen in this case is that we get a "bit already cleared" message from
2168  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2169  * e2fsck was run on this filesystem, and it must have already done the orphan
2170  * inode cleanup for us, so we can safely abort without any further action.
2171  */
2172 static void ext4_orphan_cleanup(struct super_block *sb,
2173                                 struct ext4_super_block *es)
2174 {
2175         unsigned int s_flags = sb->s_flags;
2176         int nr_orphans = 0, nr_truncates = 0;
2177 #ifdef CONFIG_QUOTA
2178         int i;
2179 #endif
2180         if (!es->s_last_orphan) {
2181                 jbd_debug(4, "no orphan inodes to clean up\n");
2182                 return;
2183         }
2184
2185         if (bdev_read_only(sb->s_bdev)) {
2186                 ext4_msg(sb, KERN_ERR, "write access "
2187                         "unavailable, skipping orphan cleanup");
2188                 return;
2189         }
2190
2191         /* Check if feature set would not allow a r/w mount */
2192         if (!ext4_feature_set_ok(sb, 0)) {
2193                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2194                          "unknown ROCOMPAT features");
2195                 return;
2196         }
2197
2198         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2199                 /* don't clear list on RO mount w/ errors */
2200                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2201                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2202                                   "clearing orphan list.\n");
2203                         es->s_last_orphan = 0;
2204                 }
2205                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2206                 return;
2207         }
2208
2209         if (s_flags & MS_RDONLY) {
2210                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2211                 sb->s_flags &= ~MS_RDONLY;
2212         }
2213 #ifdef CONFIG_QUOTA
2214         /* Needed for iput() to work correctly and not trash data */
2215         sb->s_flags |= MS_ACTIVE;
2216         /* Turn on quotas so that they are updated correctly */
2217         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2218                 if (EXT4_SB(sb)->s_qf_names[i]) {
2219                         int ret = ext4_quota_on_mount(sb, i);
2220                         if (ret < 0)
2221                                 ext4_msg(sb, KERN_ERR,
2222                                         "Cannot turn on journaled "
2223                                         "quota: error %d", ret);
2224                 }
2225         }
2226 #endif
2227
2228         while (es->s_last_orphan) {
2229                 struct inode *inode;
2230
2231                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2232                 if (IS_ERR(inode)) {
2233                         es->s_last_orphan = 0;
2234                         break;
2235                 }
2236
2237                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2238                 dquot_initialize(inode);
2239                 if (inode->i_nlink) {
2240                         if (test_opt(sb, DEBUG))
2241                                 ext4_msg(sb, KERN_DEBUG,
2242                                         "%s: truncating inode %lu to %lld bytes",
2243                                         __func__, inode->i_ino, inode->i_size);
2244                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2245                                   inode->i_ino, inode->i_size);
2246                         mutex_lock(&inode->i_mutex);
2247                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2248                         ext4_truncate(inode);
2249                         mutex_unlock(&inode->i_mutex);
2250                         nr_truncates++;
2251                 } else {
2252                         if (test_opt(sb, DEBUG))
2253                                 ext4_msg(sb, KERN_DEBUG,
2254                                         "%s: deleting unreferenced inode %lu",
2255                                         __func__, inode->i_ino);
2256                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2257                                   inode->i_ino);
2258                         nr_orphans++;
2259                 }
2260                 iput(inode);  /* The delete magic happens here! */
2261         }
2262
2263 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2264
2265         if (nr_orphans)
2266                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2267                        PLURAL(nr_orphans));
2268         if (nr_truncates)
2269                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2270                        PLURAL(nr_truncates));
2271 #ifdef CONFIG_QUOTA
2272         /* Turn quotas off */
2273         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2274                 if (sb_dqopt(sb)->files[i])
2275                         dquot_quota_off(sb, i);
2276         }
2277 #endif
2278         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2279 }
2280
2281 /*
2282  * Maximal extent format file size.
2283  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2284  * extent format containers, within a sector_t, and within i_blocks
2285  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2286  * so that won't be a limiting factor.
2287  *
2288  * However there is other limiting factor. We do store extents in the form
2289  * of starting block and length, hence the resulting length of the extent
2290  * covering maximum file size must fit into on-disk format containers as
2291  * well. Given that length is always by 1 unit bigger than max unit (because
2292  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2293  *
2294  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2295  */
2296 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2297 {
2298         loff_t res;
2299         loff_t upper_limit = MAX_LFS_FILESIZE;
2300
2301         /* small i_blocks in vfs inode? */
2302         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2303                 /*
2304                  * CONFIG_LBDAF is not enabled implies the inode
2305                  * i_block represent total blocks in 512 bytes
2306                  * 32 == size of vfs inode i_blocks * 8
2307                  */
2308                 upper_limit = (1LL << 32) - 1;
2309
2310                 /* total blocks in file system block size */
2311                 upper_limit >>= (blkbits - 9);
2312                 upper_limit <<= blkbits;
2313         }
2314
2315         /*
2316          * 32-bit extent-start container, ee_block. We lower the maxbytes
2317          * by one fs block, so ee_len can cover the extent of maximum file
2318          * size
2319          */
2320         res = (1LL << 32) - 1;
2321         res <<= blkbits;
2322
2323         /* Sanity check against vm- & vfs- imposed limits */
2324         if (res > upper_limit)
2325                 res = upper_limit;
2326
2327         return res;
2328 }
2329
2330 /*
2331  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2332  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2333  * We need to be 1 filesystem block less than the 2^48 sector limit.
2334  */
2335 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2336 {
2337         loff_t res = EXT4_NDIR_BLOCKS;
2338         int meta_blocks;
2339         loff_t upper_limit;
2340         /* This is calculated to be the largest file size for a dense, block
2341          * mapped file such that the file's total number of 512-byte sectors,
2342          * including data and all indirect blocks, does not exceed (2^48 - 1).
2343          *
2344          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2345          * number of 512-byte sectors of the file.
2346          */
2347
2348         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2349                 /*
2350                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2351                  * the inode i_block field represents total file blocks in
2352                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2353                  */
2354                 upper_limit = (1LL << 32) - 1;
2355
2356                 /* total blocks in file system block size */
2357                 upper_limit >>= (bits - 9);
2358
2359         } else {
2360                 /*
2361                  * We use 48 bit ext4_inode i_blocks
2362                  * With EXT4_HUGE_FILE_FL set the i_blocks
2363                  * represent total number of blocks in
2364                  * file system block size
2365                  */
2366                 upper_limit = (1LL << 48) - 1;
2367
2368         }
2369
2370         /* indirect blocks */
2371         meta_blocks = 1;
2372         /* double indirect blocks */
2373         meta_blocks += 1 + (1LL << (bits-2));
2374         /* tripple indirect blocks */
2375         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2376
2377         upper_limit -= meta_blocks;
2378         upper_limit <<= bits;
2379
2380         res += 1LL << (bits-2);
2381         res += 1LL << (2*(bits-2));
2382         res += 1LL << (3*(bits-2));
2383         res <<= bits;
2384         if (res > upper_limit)
2385                 res = upper_limit;
2386
2387         if (res > MAX_LFS_FILESIZE)
2388                 res = MAX_LFS_FILESIZE;
2389
2390         return res;
2391 }
2392
2393 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2394                                    ext4_fsblk_t logical_sb_block, int nr)
2395 {
2396         struct ext4_sb_info *sbi = EXT4_SB(sb);
2397         ext4_group_t bg, first_meta_bg;
2398         int has_super = 0;
2399
2400         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2401
2402         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2403             nr < first_meta_bg)
2404                 return logical_sb_block + nr + 1;
2405         bg = sbi->s_desc_per_block * nr;
2406         if (ext4_bg_has_super(sb, bg))
2407                 has_super = 1;
2408
2409         /*
2410          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2411          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2412          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2413          * compensate.
2414          */
2415         if (sb->s_blocksize == 1024 && nr == 0 &&
2416             le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) == 0)
2417                 has_super++;
2418
2419         return (has_super + ext4_group_first_block_no(sb, bg));
2420 }
2421
2422 /**
2423  * ext4_get_stripe_size: Get the stripe size.
2424  * @sbi: In memory super block info
2425  *
2426  * If we have specified it via mount option, then
2427  * use the mount option value. If the value specified at mount time is
2428  * greater than the blocks per group use the super block value.
2429  * If the super block value is greater than blocks per group return 0.
2430  * Allocator needs it be less than blocks per group.
2431  *
2432  */
2433 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2434 {
2435         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2436         unsigned long stripe_width =
2437                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2438         int ret;
2439
2440         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2441                 ret = sbi->s_stripe;
2442         else if (stripe_width <= sbi->s_blocks_per_group)
2443                 ret = stripe_width;
2444         else if (stride <= sbi->s_blocks_per_group)
2445                 ret = stride;
2446         else
2447                 ret = 0;
2448
2449         /*
2450          * If the stripe width is 1, this makes no sense and
2451          * we set it to 0 to turn off stripe handling code.
2452          */
2453         if (ret <= 1)
2454                 ret = 0;
2455
2456         return ret;
2457 }
2458
2459 /* sysfs supprt */
2460
2461 struct ext4_attr {
2462         struct attribute attr;
2463         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2464         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2465                          const char *, size_t);
2466         union {
2467                 int offset;
2468                 int deprecated_val;
2469         } u;
2470 };
2471
2472 static int parse_strtoull(const char *buf,
2473                 unsigned long long max, unsigned long long *value)
2474 {
2475         int ret;
2476
2477         ret = kstrtoull(skip_spaces(buf), 0, value);
2478         if (!ret && *value > max)
2479                 ret = -EINVAL;
2480         return ret;
2481 }
2482
2483 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2484                                               struct ext4_sb_info *sbi,
2485                                               char *buf)
2486 {
2487         return snprintf(buf, PAGE_SIZE, "%llu\n",
2488                 (s64) EXT4_C2B(sbi,
2489                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2490 }
2491
2492 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2493                                          struct ext4_sb_info *sbi, char *buf)
2494 {
2495         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2496
2497         if (!sb->s_bdev->bd_part)
2498                 return snprintf(buf, PAGE_SIZE, "0\n");
2499         return snprintf(buf, PAGE_SIZE, "%lu\n",
2500                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2501                          sbi->s_sectors_written_start) >> 1);
2502 }
2503
2504 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2505                                           struct ext4_sb_info *sbi, char *buf)
2506 {
2507         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2508
2509         if (!sb->s_bdev->bd_part)
2510                 return snprintf(buf, PAGE_SIZE, "0\n");
2511         return snprintf(buf, PAGE_SIZE, "%llu\n",
2512                         (unsigned long long)(sbi->s_kbytes_written +
2513                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2514                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2515 }
2516
2517 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2518                                           struct ext4_sb_info *sbi,
2519                                           const char *buf, size_t count)
2520 {
2521         unsigned long t;
2522         int ret;
2523
2524         ret = kstrtoul(skip_spaces(buf), 0, &t);
2525         if (ret)
2526                 return ret;
2527
2528         if (t && (!is_power_of_2(t) || t > 0x40000000))
2529                 return -EINVAL;
2530
2531         sbi->s_inode_readahead_blks = t;
2532         return count;
2533 }
2534
2535 static ssize_t sbi_ui_show(struct ext4_attr *a,
2536                            struct ext4_sb_info *sbi, char *buf)
2537 {
2538         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
2539
2540         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2541 }
2542
2543 static ssize_t sbi_ui_store(struct ext4_attr *a,
2544                             struct ext4_sb_info *sbi,
2545                             const char *buf, size_t count)
2546 {
2547         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
2548         unsigned long t;
2549         int ret;
2550
2551         ret = kstrtoul(skip_spaces(buf), 0, &t);
2552         if (ret)
2553                 return ret;
2554         *ui = t;
2555         return count;
2556 }
2557
2558 static ssize_t es_ui_show(struct ext4_attr *a,
2559                            struct ext4_sb_info *sbi, char *buf)
2560 {
2561
2562         unsigned int *ui = (unsigned int *) (((char *) sbi->s_es) +
2563                            a->u.offset);
2564
2565         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2566 }
2567
2568 static ssize_t reserved_clusters_show(struct ext4_attr *a,
2569                                   struct ext4_sb_info *sbi, char *buf)
2570 {
2571         return snprintf(buf, PAGE_SIZE, "%llu\n",
2572                 (unsigned long long) atomic64_read(&sbi->s_resv_clusters));
2573 }
2574
2575 static ssize_t reserved_clusters_store(struct ext4_attr *a,
2576                                    struct ext4_sb_info *sbi,
2577                                    const char *buf, size_t count)
2578 {
2579         unsigned long long val;
2580         int ret;
2581
2582         if (parse_strtoull(buf, -1ULL, &val))
2583                 return -EINVAL;
2584         ret = ext4_reserve_clusters(sbi, val);
2585
2586         return ret ? ret : count;
2587 }
2588
2589 static ssize_t trigger_test_error(struct ext4_attr *a,
2590                                   struct ext4_sb_info *sbi,
2591                                   const char *buf, size_t count)
2592 {
2593         int len = count;
2594
2595         if (!capable(CAP_SYS_ADMIN))
2596                 return -EPERM;
2597
2598         if (len && buf[len-1] == '\n')
2599                 len--;
2600
2601         if (len)
2602                 ext4_error(sbi->s_sb, "%.*s", len, buf);
2603         return count;
2604 }
2605
2606 static ssize_t sbi_deprecated_show(struct ext4_attr *a,
2607                                    struct ext4_sb_info *sbi, char *buf)
2608 {
2609         return snprintf(buf, PAGE_SIZE, "%d\n", a->u.deprecated_val);
2610 }
2611
2612 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2613 static struct ext4_attr ext4_attr_##_name = {                   \
2614         .attr = {.name = __stringify(_name), .mode = _mode },   \
2615         .show   = _show,                                        \
2616         .store  = _store,                                       \
2617         .u = {                                                  \
2618                 .offset = offsetof(struct ext4_sb_info, _elname),\
2619         },                                                      \
2620 }
2621
2622 #define EXT4_ATTR_OFFSET_ES(_name,_mode,_show,_store,_elname)           \
2623 static struct ext4_attr ext4_attr_##_name = {                           \
2624         .attr = {.name = __stringify(_name), .mode = _mode },           \
2625         .show   = _show,                                                \
2626         .store  = _store,                                               \
2627         .u = {                                                          \
2628                 .offset = offsetof(struct ext4_super_block, _elname),   \
2629         },                                                              \
2630 }
2631
2632 #define EXT4_ATTR(name, mode, show, store) \
2633 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2634
2635 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2636 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2637 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2638
2639 #define EXT4_RO_ATTR_ES_UI(name, elname)        \
2640         EXT4_ATTR_OFFSET_ES(name, 0444, es_ui_show, NULL, elname)
2641 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2642         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2643
2644 #define ATTR_LIST(name) &ext4_attr_##name.attr
2645 #define EXT4_DEPRECATED_ATTR(_name, _val)       \
2646 static struct ext4_attr ext4_attr_##_name = {                   \
2647         .attr = {.name = __stringify(_name), .mode = 0444 },    \
2648         .show   = sbi_deprecated_show,                          \
2649         .u = {                                                  \
2650                 .deprecated_val = _val,                         \
2651         },                                                      \
2652 }
2653
2654 EXT4_RO_ATTR(delayed_allocation_blocks);
2655 EXT4_RO_ATTR(session_write_kbytes);
2656 EXT4_RO_ATTR(lifetime_write_kbytes);
2657 EXT4_RW_ATTR(reserved_clusters);
2658 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2659                  inode_readahead_blks_store, s_inode_readahead_blks);
2660 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2661 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2662 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2663 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2664 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2665 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2666 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2667 EXT4_DEPRECATED_ATTR(max_writeback_mb_bump, 128);
2668 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
2669 EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error);
2670 EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
2671 EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst);
2672 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
2673 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
2674 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
2675 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
2676 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
2677 EXT4_RO_ATTR_ES_UI(first_error_time, s_first_error_time);
2678 EXT4_RO_ATTR_ES_UI(last_error_time, s_last_error_time);
2679
2680 static struct attribute *ext4_attrs[] = {
2681         ATTR_LIST(delayed_allocation_blocks),
2682         ATTR_LIST(session_write_kbytes),
2683         ATTR_LIST(lifetime_write_kbytes),
2684         ATTR_LIST(reserved_clusters),
2685         ATTR_LIST(inode_readahead_blks),
2686         ATTR_LIST(inode_goal),
2687         ATTR_LIST(mb_stats),
2688         ATTR_LIST(mb_max_to_scan),
2689         ATTR_LIST(mb_min_to_scan),
2690         ATTR_LIST(mb_order2_req),
2691         ATTR_LIST(mb_stream_req),
2692         ATTR_LIST(mb_group_prealloc),
2693         ATTR_LIST(max_writeback_mb_bump),
2694         ATTR_LIST(extent_max_zeroout_kb),
2695         ATTR_LIST(trigger_fs_error),
2696         ATTR_LIST(err_ratelimit_interval_ms),
2697         ATTR_LIST(err_ratelimit_burst),
2698         ATTR_LIST(warning_ratelimit_interval_ms),
2699         ATTR_LIST(warning_ratelimit_burst),
2700         ATTR_LIST(msg_ratelimit_interval_ms),
2701         ATTR_LIST(msg_ratelimit_burst),
2702         ATTR_LIST(errors_count),
2703         ATTR_LIST(first_error_time),
2704         ATTR_LIST(last_error_time),
2705         NULL,
2706 };
2707
2708 /* Features this copy of ext4 supports */
2709 EXT4_INFO_ATTR(lazy_itable_init);
2710 EXT4_INFO_ATTR(batched_discard);
2711 EXT4_INFO_ATTR(meta_bg_resize);
2712 EXT4_INFO_ATTR(encryption);
2713
2714 static struct attribute *ext4_feat_attrs[] = {
2715         ATTR_LIST(lazy_itable_init),
2716         ATTR_LIST(batched_discard),
2717         ATTR_LIST(meta_bg_resize),
2718         ATTR_LIST(encryption),
2719         NULL,
2720 };
2721
2722 static ssize_t ext4_attr_show(struct kobject *kobj,
2723                               struct attribute *attr, char *buf)
2724 {
2725         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2726                                                 s_kobj);
2727         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2728
2729         return a->show ? a->show(a, sbi, buf) : 0;
2730 }
2731
2732 static ssize_t ext4_attr_store(struct kobject *kobj,
2733                                struct attribute *attr,
2734                                const char *buf, size_t len)
2735 {
2736         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2737                                                 s_kobj);
2738         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2739
2740         return a->store ? a->store(a, sbi, buf, len) : 0;
2741 }
2742
2743 static void ext4_sb_release(struct kobject *kobj)
2744 {
2745         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2746                                                 s_kobj);
2747         complete(&sbi->s_kobj_unregister);
2748 }
2749
2750 static const struct sysfs_ops ext4_attr_ops = {
2751         .show   = ext4_attr_show,
2752         .store  = ext4_attr_store,
2753 };
2754
2755 static struct kobj_type ext4_ktype = {
2756         .default_attrs  = ext4_attrs,
2757         .sysfs_ops      = &ext4_attr_ops,
2758         .release        = ext4_sb_release,
2759 };
2760
2761 static void ext4_feat_release(struct kobject *kobj)
2762 {
2763         complete(&ext4_feat->f_kobj_unregister);
2764 }
2765
2766 static ssize_t ext4_feat_show(struct kobject *kobj,
2767                               struct attribute *attr, char *buf)
2768 {
2769         return snprintf(buf, PAGE_SIZE, "supported\n");
2770 }
2771
2772 /*
2773  * We can not use ext4_attr_show/store because it relies on the kobject
2774  * being embedded in the ext4_sb_info structure which is definitely not
2775  * true in this case.
2776  */
2777 static const struct sysfs_ops ext4_feat_ops = {
2778         .show   = ext4_feat_show,
2779         .store  = NULL,
2780 };
2781
2782 static struct kobj_type ext4_feat_ktype = {
2783         .default_attrs  = ext4_feat_attrs,
2784         .sysfs_ops      = &ext4_feat_ops,
2785         .release        = ext4_feat_release,
2786 };
2787
2788 /*
2789  * Check whether this filesystem can be mounted based on
2790  * the features present and the RDONLY/RDWR mount requested.
2791  * Returns 1 if this filesystem can be mounted as requested,
2792  * 0 if it cannot be.
2793  */
2794 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2795 {
2796         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2797                 ext4_msg(sb, KERN_ERR,
2798                         "Couldn't mount because of "
2799                         "unsupported optional features (%x)",
2800                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2801                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2802                 return 0;
2803         }
2804
2805         if (readonly)
2806                 return 1;
2807
2808         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_READONLY)) {
2809                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2810                 sb->s_flags |= MS_RDONLY;
2811                 return 1;
2812         }
2813
2814         /* Check that feature set is OK for a read-write mount */
2815         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2816                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2817                          "unsupported optional features (%x)",
2818                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2819                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2820                 return 0;
2821         }
2822         /*
2823          * Large file size enabled file system can only be mounted
2824          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2825          */
2826         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2827                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2828                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2829                                  "cannot be mounted RDWR without "
2830                                  "CONFIG_LBDAF");
2831                         return 0;
2832                 }
2833         }
2834         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2835             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2836                 ext4_msg(sb, KERN_ERR,
2837                          "Can't support bigalloc feature without "
2838                          "extents feature\n");
2839                 return 0;
2840         }
2841
2842 #ifndef CONFIG_QUOTA
2843         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
2844             !readonly) {
2845                 ext4_msg(sb, KERN_ERR,
2846                          "Filesystem with quota feature cannot be mounted RDWR "
2847                          "without CONFIG_QUOTA");
2848                 return 0;
2849         }
2850 #endif  /* CONFIG_QUOTA */
2851         return 1;
2852 }
2853
2854 /*
2855  * This function is called once a day if we have errors logged
2856  * on the file system
2857  */
2858 static void print_daily_error_info(unsigned long arg)
2859 {
2860         struct super_block *sb = (struct super_block *) arg;
2861         struct ext4_sb_info *sbi;
2862         struct ext4_super_block *es;
2863
2864         sbi = EXT4_SB(sb);
2865         es = sbi->s_es;
2866
2867         if (es->s_error_count)
2868                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2869                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2870                          le32_to_cpu(es->s_error_count));
2871         if (es->s_first_error_time) {
2872                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2873                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2874                        (int) sizeof(es->s_first_error_func),
2875                        es->s_first_error_func,
2876                        le32_to_cpu(es->s_first_error_line));
2877                 if (es->s_first_error_ino)
2878                         printk(": inode %u",
2879                                le32_to_cpu(es->s_first_error_ino));
2880                 if (es->s_first_error_block)
2881                         printk(": block %llu", (unsigned long long)
2882                                le64_to_cpu(es->s_first_error_block));
2883                 printk("\n");
2884         }
2885         if (es->s_last_error_time) {
2886                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2887                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2888                        (int) sizeof(es->s_last_error_func),
2889                        es->s_last_error_func,
2890                        le32_to_cpu(es->s_last_error_line));
2891                 if (es->s_last_error_ino)
2892                         printk(": inode %u",
2893                                le32_to_cpu(es->s_last_error_ino));
2894                 if (es->s_last_error_block)
2895                         printk(": block %llu", (unsigned long long)
2896                                le64_to_cpu(es->s_last_error_block));
2897                 printk("\n");
2898         }
2899         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2900 }
2901
2902 /* Find next suitable group and run ext4_init_inode_table */
2903 static int ext4_run_li_request(struct ext4_li_request *elr)
2904 {
2905         struct ext4_group_desc *gdp = NULL;
2906         ext4_group_t group, ngroups;
2907         struct super_block *sb;
2908         unsigned long timeout = 0;
2909         int ret = 0;
2910
2911         sb = elr->lr_super;
2912         ngroups = EXT4_SB(sb)->s_groups_count;
2913
2914         sb_start_write(sb);
2915         for (group = elr->lr_next_group; group < ngroups; group++) {
2916                 gdp = ext4_get_group_desc(sb, group, NULL);
2917                 if (!gdp) {
2918                         ret = 1;
2919                         break;
2920                 }
2921
2922                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2923                         break;
2924         }
2925
2926         if (group >= ngroups)
2927                 ret = 1;
2928
2929         if (!ret) {
2930                 timeout = jiffies;
2931                 ret = ext4_init_inode_table(sb, group,
2932                                             elr->lr_timeout ? 0 : 1);
2933                 if (elr->lr_timeout == 0) {
2934                         timeout = (jiffies - timeout) *
2935                                   elr->lr_sbi->s_li_wait_mult;
2936                         elr->lr_timeout = timeout;
2937                 }
2938                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2939                 elr->lr_next_group = group + 1;
2940         }
2941         sb_end_write(sb);
2942
2943         return ret;
2944 }
2945
2946 /*
2947  * Remove lr_request from the list_request and free the
2948  * request structure. Should be called with li_list_mtx held
2949  */
2950 static void ext4_remove_li_request(struct ext4_li_request *elr)
2951 {
2952         struct ext4_sb_info *sbi;
2953
2954         if (!elr)
2955                 return;
2956
2957         sbi = elr->lr_sbi;
2958
2959         list_del(&elr->lr_request);
2960         sbi->s_li_request = NULL;
2961         kfree(elr);
2962 }
2963
2964 static void ext4_unregister_li_request(struct super_block *sb)
2965 {
2966         mutex_lock(&ext4_li_mtx);
2967         if (!ext4_li_info) {
2968                 mutex_unlock(&ext4_li_mtx);
2969                 return;
2970         }
2971
2972         mutex_lock(&ext4_li_info->li_list_mtx);
2973         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2974         mutex_unlock(&ext4_li_info->li_list_mtx);
2975         mutex_unlock(&ext4_li_mtx);
2976 }
2977
2978 static struct task_struct *ext4_lazyinit_task;
2979
2980 /*
2981  * This is the function where ext4lazyinit thread lives. It walks
2982  * through the request list searching for next scheduled filesystem.
2983  * When such a fs is found, run the lazy initialization request
2984  * (ext4_rn_li_request) and keep track of the time spend in this
2985  * function. Based on that time we compute next schedule time of
2986  * the request. When walking through the list is complete, compute
2987  * next waking time and put itself into sleep.
2988  */
2989 static int ext4_lazyinit_thread(void *arg)
2990 {
2991         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2992         struct list_head *pos, *n;
2993         struct ext4_li_request *elr;
2994         unsigned long next_wakeup, cur;
2995
2996         BUG_ON(NULL == eli);
2997
2998 cont_thread:
2999         while (true) {
3000                 next_wakeup = MAX_JIFFY_OFFSET;
3001
3002                 mutex_lock(&eli->li_list_mtx);
3003                 if (list_empty(&eli->li_request_list)) {
3004                         mutex_unlock(&eli->li_list_mtx);
3005                         goto exit_thread;
3006                 }
3007
3008                 list_for_each_safe(pos, n, &eli->li_request_list) {
3009                         elr = list_entry(pos, struct ext4_li_request,
3010                                          lr_request);
3011
3012                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
3013                                 if (ext4_run_li_request(elr) != 0) {
3014                                         /* error, remove the lazy_init job */
3015                                         ext4_remove_li_request(elr);
3016                                         continue;
3017                                 }
3018                         }
3019
3020                         if (time_before(elr->lr_next_sched, next_wakeup))
3021                                 next_wakeup = elr->lr_next_sched;
3022                 }
3023                 mutex_unlock(&eli->li_list_mtx);
3024
3025                 try_to_freeze();
3026
3027                 cur = jiffies;
3028                 if ((time_after_eq(cur, next_wakeup)) ||
3029                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3030                         cond_resched();
3031                         continue;
3032                 }
3033
3034                 schedule_timeout_interruptible(next_wakeup - cur);
3035
3036                 if (kthread_should_stop()) {
3037                         ext4_clear_request_list();
3038                         goto exit_thread;
3039                 }
3040         }
3041
3042 exit_thread:
3043         /*
3044          * It looks like the request list is empty, but we need
3045          * to check it under the li_list_mtx lock, to prevent any
3046          * additions into it, and of course we should lock ext4_li_mtx
3047          * to atomically free the list and ext4_li_info, because at
3048          * this point another ext4 filesystem could be registering
3049          * new one.
3050          */
3051         mutex_lock(&ext4_li_mtx);
3052         mutex_lock(&eli->li_list_mtx);
3053         if (!list_empty(&eli->li_request_list)) {
3054                 mutex_unlock(&eli->li_list_mtx);
3055                 mutex_unlock(&ext4_li_mtx);
3056                 goto cont_thread;
3057         }
3058         mutex_unlock(&eli->li_list_mtx);
3059         kfree(ext4_li_info);
3060         ext4_li_info = NULL;
3061         mutex_unlock(&ext4_li_mtx);
3062
3063         return 0;
3064 }
3065
3066 static void ext4_clear_request_list(void)
3067 {
3068         struct list_head *pos, *n;
3069         struct ext4_li_request *elr;
3070
3071         mutex_lock(&ext4_li_info->li_list_mtx);
3072         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3073                 elr = list_entry(pos, struct ext4_li_request,
3074                                  lr_request);
3075                 ext4_remove_li_request(elr);
3076         }
3077         mutex_unlock(&ext4_li_info->li_list_mtx);
3078 }
3079
3080 static int ext4_run_lazyinit_thread(void)
3081 {
3082         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3083                                          ext4_li_info, "ext4lazyinit");
3084         if (IS_ERR(ext4_lazyinit_task)) {
3085                 int err = PTR_ERR(ext4_lazyinit_task);
3086                 ext4_clear_request_list();
3087                 kfree(ext4_li_info);
3088                 ext4_li_info = NULL;
3089                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3090                                  "initialization thread\n",
3091                                  err);
3092                 return err;
3093         }
3094         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3095         return 0;
3096 }
3097
3098 /*
3099  * Check whether it make sense to run itable init. thread or not.
3100  * If there is at least one uninitialized inode table, return
3101  * corresponding group number, else the loop goes through all
3102  * groups and return total number of groups.
3103  */
3104 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3105 {
3106         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3107         struct ext4_group_desc *gdp = NULL;
3108
3109         for (group = 0; group < ngroups; group++) {
3110                 gdp = ext4_get_group_desc(sb, group, NULL);
3111                 if (!gdp)
3112                         continue;
3113
3114                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3115                         break;
3116         }
3117
3118         return group;
3119 }
3120
3121 static int ext4_li_info_new(void)
3122 {
3123         struct ext4_lazy_init *eli = NULL;
3124
3125         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3126         if (!eli)
3127                 return -ENOMEM;
3128
3129         INIT_LIST_HEAD(&eli->li_request_list);
3130         mutex_init(&eli->li_list_mtx);
3131
3132         eli->li_state |= EXT4_LAZYINIT_QUIT;
3133
3134         ext4_li_info = eli;
3135
3136         return 0;
3137 }
3138
3139 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3140                                             ext4_group_t start)
3141 {
3142         struct ext4_sb_info *sbi = EXT4_SB(sb);
3143         struct ext4_li_request *elr;
3144
3145         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3146         if (!elr)
3147                 return NULL;
3148
3149         elr->lr_super = sb;
3150         elr->lr_sbi = sbi;
3151         elr->lr_next_group = start;
3152
3153         /*
3154          * Randomize first schedule time of the request to
3155          * spread the inode table initialization requests
3156          * better.
3157          */
3158         elr->lr_next_sched = jiffies + (prandom_u32() %
3159                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3160         return elr;
3161 }
3162
3163 int ext4_register_li_request(struct super_block *sb,
3164                              ext4_group_t first_not_zeroed)
3165 {
3166         struct ext4_sb_info *sbi = EXT4_SB(sb);
3167         struct ext4_li_request *elr = NULL;
3168         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3169         int ret = 0;
3170
3171         mutex_lock(&ext4_li_mtx);
3172         if (sbi->s_li_request != NULL) {
3173                 /*
3174                  * Reset timeout so it can be computed again, because
3175                  * s_li_wait_mult might have changed.
3176                  */
3177                 sbi->s_li_request->lr_timeout = 0;
3178                 goto out;
3179         }
3180
3181         if (first_not_zeroed == ngroups ||
3182             (sb->s_flags & MS_RDONLY) ||
3183             !test_opt(sb, INIT_INODE_TABLE))
3184                 goto out;
3185
3186         elr = ext4_li_request_new(sb, first_not_zeroed);
3187         if (!elr) {
3188                 ret = -ENOMEM;
3189                 goto out;
3190         }
3191
3192         if (NULL == ext4_li_info) {
3193                 ret = ext4_li_info_new();
3194                 if (ret)
3195                         goto out;
3196         }
3197
3198         mutex_lock(&ext4_li_info->li_list_mtx);
3199         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3200         mutex_unlock(&ext4_li_info->li_list_mtx);
3201
3202         sbi->s_li_request = elr;
3203         /*
3204          * set elr to NULL here since it has been inserted to
3205          * the request_list and the removal and free of it is
3206          * handled by ext4_clear_request_list from now on.
3207          */
3208         elr = NULL;
3209
3210         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3211                 ret = ext4_run_lazyinit_thread();
3212                 if (ret)
3213                         goto out;
3214         }
3215 out:
3216         mutex_unlock(&ext4_li_mtx);
3217         if (ret)
3218                 kfree(elr);
3219         return ret;
3220 }
3221
3222 /*
3223  * We do not need to lock anything since this is called on
3224  * module unload.
3225  */
3226 static void ext4_destroy_lazyinit_thread(void)
3227 {
3228         /*
3229          * If thread exited earlier
3230          * there's nothing to be done.
3231          */
3232         if (!ext4_li_info || !ext4_lazyinit_task)
3233                 return;
3234
3235         kthread_stop(ext4_lazyinit_task);
3236 }
3237
3238 static int set_journal_csum_feature_set(struct super_block *sb)
3239 {
3240         int ret = 1;
3241         int compat, incompat;
3242         struct ext4_sb_info *sbi = EXT4_SB(sb);
3243
3244         if (ext4_has_metadata_csum(sb)) {
3245                 /* journal checksum v3 */
3246                 compat = 0;
3247                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3248         } else {
3249                 /* journal checksum v1 */
3250                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3251                 incompat = 0;
3252         }
3253
3254         jbd2_journal_clear_features(sbi->s_journal,
3255                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3256                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3257                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3258         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3259                 ret = jbd2_journal_set_features(sbi->s_journal,
3260                                 compat, 0,
3261                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3262                                 incompat);
3263         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3264                 ret = jbd2_journal_set_features(sbi->s_journal,
3265                                 compat, 0,
3266                                 incompat);
3267                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3268                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3269         } else {
3270                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3271                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3272         }
3273
3274         return ret;
3275 }
3276
3277 /*
3278  * Note: calculating the overhead so we can be compatible with
3279  * historical BSD practice is quite difficult in the face of
3280  * clusters/bigalloc.  This is because multiple metadata blocks from
3281  * different block group can end up in the same allocation cluster.
3282  * Calculating the exact overhead in the face of clustered allocation
3283  * requires either O(all block bitmaps) in memory or O(number of block
3284  * groups**2) in time.  We will still calculate the superblock for
3285  * older file systems --- and if we come across with a bigalloc file
3286  * system with zero in s_overhead_clusters the estimate will be close to
3287  * correct especially for very large cluster sizes --- but for newer
3288  * file systems, it's better to calculate this figure once at mkfs
3289  * time, and store it in the superblock.  If the superblock value is
3290  * present (even for non-bigalloc file systems), we will use it.
3291  */
3292 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3293                           char *buf)
3294 {
3295         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3296         struct ext4_group_desc  *gdp;
3297         ext4_fsblk_t            first_block, last_block, b;
3298         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3299         int                     s, j, count = 0;
3300
3301         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC))
3302                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3303                         sbi->s_itb_per_group + 2);
3304
3305         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3306                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3307         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3308         for (i = 0; i < ngroups; i++) {
3309                 gdp = ext4_get_group_desc(sb, i, NULL);
3310                 b = ext4_block_bitmap(sb, gdp);
3311                 if (b >= first_block && b <= last_block) {
3312                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3313                         count++;
3314                 }
3315                 b = ext4_inode_bitmap(sb, gdp);
3316                 if (b >= first_block && b <= last_block) {
3317                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3318                         count++;
3319                 }
3320                 b = ext4_inode_table(sb, gdp);
3321                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3322                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3323                                 int c = EXT4_B2C(sbi, b - first_block);
3324                                 ext4_set_bit(c, buf);
3325                                 count++;
3326                         }
3327                 if (i != grp)
3328                         continue;
3329                 s = 0;
3330                 if (ext4_bg_has_super(sb, grp)) {
3331                         ext4_set_bit(s++, buf);
3332                         count++;
3333                 }
3334                 for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3335                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3336                         count++;
3337                 }
3338         }
3339         if (!count)
3340                 return 0;
3341         return EXT4_CLUSTERS_PER_GROUP(sb) -
3342                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3343 }
3344
3345 /*
3346  * Compute the overhead and stash it in sbi->s_overhead
3347  */
3348 int ext4_calculate_overhead(struct super_block *sb)
3349 {
3350         struct ext4_sb_info *sbi = EXT4_SB(sb);
3351         struct ext4_super_block *es = sbi->s_es;
3352         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3353         ext4_fsblk_t overhead = 0;
3354         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3355
3356         if (!buf)
3357                 return -ENOMEM;
3358
3359         /*
3360          * Compute the overhead (FS structures).  This is constant
3361          * for a given filesystem unless the number of block groups
3362          * changes so we cache the previous value until it does.
3363          */
3364
3365         /*
3366          * All of the blocks before first_data_block are overhead
3367          */
3368         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3369
3370         /*
3371          * Add the overhead found in each block group
3372          */
3373         for (i = 0; i < ngroups; i++) {
3374                 int blks;
3375
3376                 blks = count_overhead(sb, i, buf);
3377                 overhead += blks;
3378                 if (blks)
3379                         memset(buf, 0, PAGE_SIZE);
3380                 cond_resched();
3381         }
3382         /* Add the internal journal blocks as well */
3383         if (sbi->s_journal && !sbi->journal_bdev)
3384                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3385
3386         sbi->s_overhead = overhead;
3387         smp_wmb();
3388         free_page((unsigned long) buf);
3389         return 0;
3390 }
3391
3392
3393 static ext4_fsblk_t ext4_calculate_resv_clusters(struct super_block *sb)
3394 {
3395         ext4_fsblk_t resv_clusters;
3396
3397         /*
3398          * There's no need to reserve anything when we aren't using extents.
3399          * The space estimates are exact, there are no unwritten extents,
3400          * hole punching doesn't need new metadata... This is needed especially
3401          * to keep ext2/3 backward compatibility.
3402          */
3403         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
3404                 return 0;
3405         /*
3406          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3407          * This should cover the situations where we can not afford to run
3408          * out of space like for example punch hole, or converting
3409          * unwritten extents in delalloc path. In most cases such
3410          * allocation would require 1, or 2 blocks, higher numbers are
3411          * very rare.
3412          */
3413         resv_clusters = ext4_blocks_count(EXT4_SB(sb)->s_es) >>
3414                         EXT4_SB(sb)->s_cluster_bits;
3415
3416         do_div(resv_clusters, 50);
3417         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3418
3419         return resv_clusters;
3420 }
3421
3422
3423 static int ext4_reserve_clusters(struct ext4_sb_info *sbi, ext4_fsblk_t count)
3424 {
3425         ext4_fsblk_t clusters = ext4_blocks_count(sbi->s_es) >>
3426                                 sbi->s_cluster_bits;
3427
3428         if (count >= clusters)
3429                 return -EINVAL;
3430
3431         atomic64_set(&sbi->s_resv_clusters, count);
3432         return 0;
3433 }
3434
3435 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3436 {
3437         char *orig_data = kstrdup(data, GFP_KERNEL);
3438         struct buffer_head *bh;
3439         struct ext4_super_block *es = NULL;
3440         struct ext4_sb_info *sbi;
3441         ext4_fsblk_t block;
3442         ext4_fsblk_t sb_block = get_sb_block(&data);
3443         ext4_fsblk_t logical_sb_block;
3444         unsigned long offset = 0;
3445         unsigned long journal_devnum = 0;
3446         unsigned long def_mount_opts;
3447         struct inode *root;
3448         char *cp;
3449         const char *descr;
3450         int ret = -ENOMEM;
3451         int blocksize, clustersize;
3452         unsigned int db_count;
3453         unsigned int i;
3454         int needs_recovery, has_huge_files, has_bigalloc;
3455         __u64 blocks_count;
3456         int err = 0;
3457         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3458         ext4_group_t first_not_zeroed;
3459
3460         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3461         if (!sbi)
3462                 goto out_free_orig;
3463
3464         sbi->s_blockgroup_lock =
3465                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3466         if (!sbi->s_blockgroup_lock) {
3467                 kfree(sbi);
3468                 goto out_free_orig;
3469         }
3470         sb->s_fs_info = sbi;
3471         sbi->s_sb = sb;
3472         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3473         sbi->s_sb_block = sb_block;
3474         if (sb->s_bdev->bd_part)
3475                 sbi->s_sectors_written_start =
3476                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3477
3478         /* Cleanup superblock name */
3479         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3480                 *cp = '!';
3481
3482         /* -EINVAL is default */
3483         ret = -EINVAL;
3484         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3485         if (!blocksize) {
3486                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3487                 goto out_fail;
3488         }
3489
3490         /*
3491          * The ext4 superblock will not be buffer aligned for other than 1kB
3492          * block sizes.  We need to calculate the offset from buffer start.
3493          */
3494         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3495                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3496                 offset = do_div(logical_sb_block, blocksize);
3497         } else {
3498                 logical_sb_block = sb_block;
3499         }
3500
3501         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3502                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3503                 goto out_fail;
3504         }
3505         /*
3506          * Note: s_es must be initialized as soon as possible because
3507          *       some ext4 macro-instructions depend on its value
3508          */
3509         es = (struct ext4_super_block *) (bh->b_data + offset);
3510         sbi->s_es = es;
3511         sb->s_magic = le16_to_cpu(es->s_magic);
3512         if (sb->s_magic != EXT4_SUPER_MAGIC)
3513                 goto cantfind_ext4;
3514         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3515
3516         /* Warn if metadata_csum and gdt_csum are both set. */
3517         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3518                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
3519             EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
3520                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3521                              "redundant flags; please run fsck.");
3522
3523         /* Check for a known checksum algorithm */
3524         if (!ext4_verify_csum_type(sb, es)) {
3525                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3526                          "unknown checksum algorithm.");
3527                 silent = 1;
3528                 goto cantfind_ext4;
3529         }
3530
3531         /* Load the checksum driver */
3532         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3533                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3534                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3535                 if (IS_ERR(sbi->s_chksum_driver)) {
3536                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3537                         ret = PTR_ERR(sbi->s_chksum_driver);
3538                         sbi->s_chksum_driver = NULL;
3539                         goto failed_mount;
3540                 }
3541         }
3542
3543         /* Check superblock checksum */
3544         if (!ext4_superblock_csum_verify(sb, es)) {
3545                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3546                          "invalid superblock checksum.  Run e2fsck?");
3547                 silent = 1;
3548                 goto cantfind_ext4;
3549         }
3550
3551         /* Precompute checksum seed for all metadata */
3552         if (ext4_has_metadata_csum(sb))
3553                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3554                                                sizeof(es->s_uuid));
3555
3556         /* Set defaults before we parse the mount options */
3557         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3558         set_opt(sb, INIT_INODE_TABLE);
3559         if (def_mount_opts & EXT4_DEFM_DEBUG)
3560                 set_opt(sb, DEBUG);
3561         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3562                 set_opt(sb, GRPID);
3563         if (def_mount_opts & EXT4_DEFM_UID16)
3564                 set_opt(sb, NO_UID32);
3565         /* xattr user namespace & acls are now defaulted on */
3566         set_opt(sb, XATTR_USER);
3567 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3568         set_opt(sb, POSIX_ACL);
3569 #endif
3570         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3571         if (ext4_has_metadata_csum(sb))
3572                 set_opt(sb, JOURNAL_CHECKSUM);
3573
3574         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3575                 set_opt(sb, JOURNAL_DATA);
3576         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3577                 set_opt(sb, ORDERED_DATA);
3578         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3579                 set_opt(sb, WRITEBACK_DATA);
3580
3581         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3582                 set_opt(sb, ERRORS_PANIC);
3583         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3584                 set_opt(sb, ERRORS_CONT);
3585         else
3586                 set_opt(sb, ERRORS_RO);
3587         /* block_validity enabled by default; disable with noblock_validity */
3588         set_opt(sb, BLOCK_VALIDITY);
3589         if (def_mount_opts & EXT4_DEFM_DISCARD)
3590                 set_opt(sb, DISCARD);
3591
3592         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3593         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3594         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3595         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3596         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3597
3598         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3599                 set_opt(sb, BARRIER);
3600
3601         /*
3602          * enable delayed allocation by default
3603          * Use -o nodelalloc to turn it off
3604          */
3605         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3606             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3607                 set_opt(sb, DELALLOC);
3608
3609         /*
3610          * set default s_li_wait_mult for lazyinit, for the case there is
3611          * no mount option specified.
3612          */
3613         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3614
3615         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3616                            &journal_devnum, &journal_ioprio, 0)) {
3617                 ext4_msg(sb, KERN_WARNING,
3618                          "failed to parse options in superblock: %s",
3619                          sbi->s_es->s_mount_opts);
3620         }
3621         sbi->s_def_mount_opt = sbi->s_mount_opt;
3622         if (!parse_options((char *) data, sb, &journal_devnum,
3623                            &journal_ioprio, 0))
3624                 goto failed_mount;
3625
3626         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3627                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3628                             "with data=journal disables delayed "
3629                             "allocation and O_DIRECT support!\n");
3630                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3631                         ext4_msg(sb, KERN_ERR, "can't mount with "
3632                                  "both data=journal and delalloc");
3633                         goto failed_mount;
3634                 }
3635                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3636                         ext4_msg(sb, KERN_ERR, "can't mount with "
3637                                  "both data=journal and dioread_nolock");
3638                         goto failed_mount;
3639                 }
3640                 if (test_opt(sb, DAX)) {
3641                         ext4_msg(sb, KERN_ERR, "can't mount with "
3642                                  "both data=journal and dax");
3643                         goto failed_mount;
3644                 }
3645                 if (test_opt(sb, DELALLOC))
3646                         clear_opt(sb, DELALLOC);
3647         }
3648
3649         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3650                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3651
3652         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3653             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3654              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3655              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3656                 ext4_msg(sb, KERN_WARNING,
3657                        "feature flags set on rev 0 fs, "
3658                        "running e2fsck is recommended");
3659
3660         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3661                 set_opt2(sb, HURD_COMPAT);
3662                 if (EXT4_HAS_INCOMPAT_FEATURE(sb,
3663                                               EXT4_FEATURE_INCOMPAT_64BIT)) {
3664                         ext4_msg(sb, KERN_ERR,
3665                                  "The Hurd can't support 64-bit file systems");
3666                         goto failed_mount;
3667                 }
3668         }
3669
3670         if (IS_EXT2_SB(sb)) {
3671                 if (ext2_feature_set_ok(sb))
3672                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3673                                  "using the ext4 subsystem");
3674                 else {
3675                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3676                                  "to feature incompatibilities");
3677                         goto failed_mount;
3678                 }
3679         }
3680
3681         if (IS_EXT3_SB(sb)) {
3682                 if (ext3_feature_set_ok(sb))
3683                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3684                                  "using the ext4 subsystem");
3685                 else {
3686                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3687                                  "to feature incompatibilities");
3688                         goto failed_mount;
3689                 }
3690         }
3691
3692         /*
3693          * Check feature flags regardless of the revision level, since we
3694          * previously didn't change the revision level when setting the flags,
3695          * so there is a chance incompat flags are set on a rev 0 filesystem.
3696          */
3697         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3698                 goto failed_mount;
3699
3700         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3701         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3702             blocksize > EXT4_MAX_BLOCK_SIZE) {
3703                 ext4_msg(sb, KERN_ERR,
3704                        "Unsupported filesystem blocksize %d", blocksize);
3705                 goto failed_mount;
3706         }
3707
3708         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3709                 if (blocksize != PAGE_SIZE) {
3710                         ext4_msg(sb, KERN_ERR,
3711                                         "error: unsupported blocksize for dax");
3712                         goto failed_mount;
3713                 }
3714                 if (!sb->s_bdev->bd_disk->fops->direct_access) {
3715                         ext4_msg(sb, KERN_ERR,
3716                                         "error: device does not support dax");
3717                         goto failed_mount;
3718                 }
3719         }
3720
3721         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT) &&
3722             es->s_encryption_level) {
3723                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3724                          es->s_encryption_level);
3725                 goto failed_mount;
3726         }
3727
3728         if (sb->s_blocksize != blocksize) {
3729                 /* Validate the filesystem blocksize */
3730                 if (!sb_set_blocksize(sb, blocksize)) {
3731                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3732                                         blocksize);
3733                         goto failed_mount;
3734                 }
3735
3736                 brelse(bh);
3737                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3738                 offset = do_div(logical_sb_block, blocksize);
3739                 bh = sb_bread_unmovable(sb, logical_sb_block);
3740                 if (!bh) {
3741                         ext4_msg(sb, KERN_ERR,
3742                                "Can't read superblock on 2nd try");
3743                         goto failed_mount;
3744                 }
3745                 es = (struct ext4_super_block *)(bh->b_data + offset);
3746                 sbi->s_es = es;
3747                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3748                         ext4_msg(sb, KERN_ERR,
3749                                "Magic mismatch, very weird!");
3750                         goto failed_mount;
3751                 }
3752         }
3753
3754         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3755                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3756         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3757                                                       has_huge_files);
3758         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3759
3760         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3761                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3762                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3763         } else {
3764                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3765                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3766                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3767                     (!is_power_of_2(sbi->s_inode_size)) ||
3768                     (sbi->s_inode_size > blocksize)) {
3769                         ext4_msg(sb, KERN_ERR,
3770                                "unsupported inode size: %d",
3771                                sbi->s_inode_size);
3772                         goto failed_mount;
3773                 }
3774                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3775                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3776         }
3777
3778         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3779         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3780                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3781                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3782                     !is_power_of_2(sbi->s_desc_size)) {
3783                         ext4_msg(sb, KERN_ERR,
3784                                "unsupported descriptor size %lu",
3785                                sbi->s_desc_size);
3786                         goto failed_mount;
3787                 }
3788         } else
3789                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3790
3791         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3792         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3793         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3794                 goto cantfind_ext4;
3795
3796         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3797         if (sbi->s_inodes_per_block == 0)
3798                 goto cantfind_ext4;
3799         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3800                                         sbi->s_inodes_per_block;
3801         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3802         sbi->s_sbh = bh;
3803         sbi->s_mount_state = le16_to_cpu(es->s_state);
3804         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3805         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3806
3807         for (i = 0; i < 4; i++)
3808                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3809         sbi->s_def_hash_version = es->s_def_hash_version;
3810         if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX)) {
3811                 i = le32_to_cpu(es->s_flags);
3812                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
3813                         sbi->s_hash_unsigned = 3;
3814                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3815 #ifdef __CHAR_UNSIGNED__
3816                         if (!(sb->s_flags & MS_RDONLY))
3817                                 es->s_flags |=
3818                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3819                         sbi->s_hash_unsigned = 3;
3820 #else
3821                         if (!(sb->s_flags & MS_RDONLY))
3822                                 es->s_flags |=
3823                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3824 #endif
3825                 }
3826         }
3827
3828         /* Handle clustersize */
3829         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3830         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3831                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3832         if (has_bigalloc) {
3833                 if (clustersize < blocksize) {
3834                         ext4_msg(sb, KERN_ERR,
3835                                  "cluster size (%d) smaller than "
3836                                  "block size (%d)", clustersize, blocksize);
3837                         goto failed_mount;
3838                 }
3839                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3840                         le32_to_cpu(es->s_log_block_size);
3841                 sbi->s_clusters_per_group =
3842                         le32_to_cpu(es->s_clusters_per_group);
3843                 if (sbi->s_clusters_per_group > blocksize * 8) {
3844                         ext4_msg(sb, KERN_ERR,
3845                                  "#clusters per group too big: %lu",
3846                                  sbi->s_clusters_per_group);
3847                         goto failed_mount;
3848                 }
3849                 if (sbi->s_blocks_per_group !=
3850                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3851                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3852                                  "clusters per group (%lu) inconsistent",
3853                                  sbi->s_blocks_per_group,
3854                                  sbi->s_clusters_per_group);
3855                         goto failed_mount;
3856                 }
3857         } else {
3858                 if (clustersize != blocksize) {
3859                         ext4_warning(sb, "fragment/cluster size (%d) != "
3860                                      "block size (%d)", clustersize,
3861                                      blocksize);
3862                         clustersize = blocksize;
3863                 }
3864                 if (sbi->s_blocks_per_group > blocksize * 8) {
3865                         ext4_msg(sb, KERN_ERR,
3866                                  "#blocks per group too big: %lu",
3867                                  sbi->s_blocks_per_group);
3868                         goto failed_mount;
3869                 }
3870                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3871                 sbi->s_cluster_bits = 0;
3872         }
3873         sbi->s_cluster_ratio = clustersize / blocksize;
3874
3875         if (sbi->s_inodes_per_group > blocksize * 8) {
3876                 ext4_msg(sb, KERN_ERR,
3877                        "#inodes per group too big: %lu",
3878                        sbi->s_inodes_per_group);
3879                 goto failed_mount;
3880         }
3881
3882         /* Do we have standard group size of clustersize * 8 blocks ? */
3883         if (sbi->s_blocks_per_group == clustersize << 3)
3884                 set_opt2(sb, STD_GROUP_SIZE);
3885
3886         /*
3887          * Test whether we have more sectors than will fit in sector_t,
3888          * and whether the max offset is addressable by the page cache.
3889          */
3890         err = generic_check_addressable(sb->s_blocksize_bits,
3891                                         ext4_blocks_count(es));
3892         if (err) {
3893                 ext4_msg(sb, KERN_ERR, "filesystem"
3894                          " too large to mount safely on this system");
3895                 if (sizeof(sector_t) < 8)
3896                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3897                 goto failed_mount;
3898         }
3899
3900         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3901                 goto cantfind_ext4;
3902
3903         /* check blocks count against device size */
3904         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3905         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3906                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3907                        "exceeds size of device (%llu blocks)",
3908                        ext4_blocks_count(es), blocks_count);
3909                 goto failed_mount;
3910         }
3911
3912         /*
3913          * It makes no sense for the first data block to be beyond the end
3914          * of the filesystem.
3915          */
3916         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3917                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3918                          "block %u is beyond end of filesystem (%llu)",
3919                          le32_to_cpu(es->s_first_data_block),
3920                          ext4_blocks_count(es));
3921                 goto failed_mount;
3922         }
3923         blocks_count = (ext4_blocks_count(es) -
3924                         le32_to_cpu(es->s_first_data_block) +
3925                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3926         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3927         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3928                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3929                        "(block count %llu, first data block %u, "
3930                        "blocks per group %lu)", sbi->s_groups_count,
3931                        ext4_blocks_count(es),
3932                        le32_to_cpu(es->s_first_data_block),
3933                        EXT4_BLOCKS_PER_GROUP(sb));
3934                 goto failed_mount;
3935         }
3936         sbi->s_groups_count = blocks_count;
3937         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3938                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3939         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3940                    EXT4_DESC_PER_BLOCK(sb);
3941         sbi->s_group_desc = ext4_kvmalloc(db_count *
3942                                           sizeof(struct buffer_head *),
3943                                           GFP_KERNEL);
3944         if (sbi->s_group_desc == NULL) {
3945                 ext4_msg(sb, KERN_ERR, "not enough memory");
3946                 ret = -ENOMEM;
3947                 goto failed_mount;
3948         }
3949
3950         if (ext4_proc_root)
3951                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3952
3953         if (sbi->s_proc)
3954                 proc_create_data("options", S_IRUGO, sbi->s_proc,
3955                                  &ext4_seq_options_fops, sb);
3956
3957         bgl_lock_init(sbi->s_blockgroup_lock);
3958
3959         for (i = 0; i < db_count; i++) {
3960                 block = descriptor_loc(sb, logical_sb_block, i);
3961                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
3962                 if (!sbi->s_group_desc[i]) {
3963                         ext4_msg(sb, KERN_ERR,
3964                                "can't read group descriptor %d", i);
3965                         db_count = i;
3966                         goto failed_mount2;
3967                 }
3968         }
3969         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3970                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3971                 goto failed_mount2;
3972         }
3973
3974         sbi->s_gdb_count = db_count;
3975         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3976         spin_lock_init(&sbi->s_next_gen_lock);
3977
3978         setup_timer(&sbi->s_err_report, print_daily_error_info,
3979                 (unsigned long) sb);
3980
3981         /* Register extent status tree shrinker */
3982         if (ext4_es_register_shrinker(sbi))
3983                 goto failed_mount3;
3984
3985         sbi->s_stripe = ext4_get_stripe_size(sbi);
3986         sbi->s_extent_max_zeroout_kb = 32;
3987
3988         /*
3989          * set up enough so that it can read an inode
3990          */
3991         sb->s_op = &ext4_sops;
3992         sb->s_export_op = &ext4_export_ops;
3993         sb->s_xattr = ext4_xattr_handlers;
3994 #ifdef CONFIG_QUOTA
3995         sb->dq_op = &ext4_quota_operations;
3996         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
3997                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
3998         else
3999                 sb->s_qcop = &ext4_qctl_operations;
4000         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
4001 #endif
4002         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4003
4004         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4005         mutex_init(&sbi->s_orphan_lock);
4006
4007         sb->s_root = NULL;
4008
4009         needs_recovery = (es->s_last_orphan != 0 ||
4010                           EXT4_HAS_INCOMPAT_FEATURE(sb,
4011                                     EXT4_FEATURE_INCOMPAT_RECOVER));
4012
4013         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
4014             !(sb->s_flags & MS_RDONLY))
4015                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4016                         goto failed_mount3a;
4017
4018         /*
4019          * The first inode we look at is the journal inode.  Don't try
4020          * root first: it may be modified in the journal!
4021          */
4022         if (!test_opt(sb, NOLOAD) &&
4023             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4024                 if (ext4_load_journal(sb, es, journal_devnum))
4025                         goto failed_mount3a;
4026         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
4027               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4028                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4029                        "suppressed and not mounted read-only");
4030                 goto failed_mount_wq;
4031         } else {
4032                 clear_opt(sb, DATA_FLAGS);
4033                 sbi->s_journal = NULL;
4034                 needs_recovery = 0;
4035                 goto no_journal;
4036         }
4037
4038         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) &&
4039             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4040                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4041                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4042                 goto failed_mount_wq;
4043         }
4044
4045         if (!set_journal_csum_feature_set(sb)) {
4046                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4047                          "feature set");
4048                 goto failed_mount_wq;
4049         }
4050
4051         /* We have now updated the journal if required, so we can
4052          * validate the data journaling mode. */
4053         switch (test_opt(sb, DATA_FLAGS)) {
4054         case 0:
4055                 /* No mode set, assume a default based on the journal
4056                  * capabilities: ORDERED_DATA if the journal can
4057                  * cope, else JOURNAL_DATA
4058                  */
4059                 if (jbd2_journal_check_available_features
4060                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
4061                         set_opt(sb, ORDERED_DATA);
4062                 else
4063                         set_opt(sb, JOURNAL_DATA);
4064                 break;
4065
4066         case EXT4_MOUNT_ORDERED_DATA:
4067         case EXT4_MOUNT_WRITEBACK_DATA:
4068                 if (!jbd2_journal_check_available_features
4069                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4070                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4071                                "requested data journaling mode");
4072                         goto failed_mount_wq;
4073                 }
4074         default:
4075                 break;
4076         }
4077         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4078
4079         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4080
4081 no_journal:
4082         if (ext4_mballoc_ready) {
4083                 sbi->s_mb_cache = ext4_xattr_create_cache(sb->s_id);
4084                 if (!sbi->s_mb_cache) {
4085                         ext4_msg(sb, KERN_ERR, "Failed to create an mb_cache");
4086                         goto failed_mount_wq;
4087                 }
4088         }
4089
4090         if ((DUMMY_ENCRYPTION_ENABLED(sbi) ||
4091              EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT)) &&
4092             (blocksize != PAGE_CACHE_SIZE)) {
4093                 ext4_msg(sb, KERN_ERR,
4094                          "Unsupported blocksize for fs encryption");
4095                 goto failed_mount_wq;
4096         }
4097
4098         if (DUMMY_ENCRYPTION_ENABLED(sbi) &&
4099             !(sb->s_flags & MS_RDONLY) &&
4100             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT)) {
4101                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT);
4102                 ext4_commit_super(sb, 1);
4103         }
4104
4105         /*
4106          * Get the # of file system overhead blocks from the
4107          * superblock if present.
4108          */
4109         if (es->s_overhead_clusters)
4110                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4111         else {
4112                 err = ext4_calculate_overhead(sb);
4113                 if (err)
4114                         goto failed_mount_wq;
4115         }
4116
4117         /*
4118          * The maximum number of concurrent works can be high and
4119          * concurrency isn't really necessary.  Limit it to 1.
4120          */
4121         EXT4_SB(sb)->rsv_conversion_wq =
4122                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4123         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4124                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4125                 ret = -ENOMEM;
4126                 goto failed_mount4;
4127         }
4128
4129         /*
4130          * The jbd2_journal_load will have done any necessary log recovery,
4131          * so we can safely mount the rest of the filesystem now.
4132          */
4133
4134         root = ext4_iget(sb, EXT4_ROOT_INO);
4135         if (IS_ERR(root)) {
4136                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4137                 ret = PTR_ERR(root);
4138                 root = NULL;
4139                 goto failed_mount4;
4140         }
4141         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4142                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4143                 iput(root);
4144                 goto failed_mount4;
4145         }
4146         sb->s_root = d_make_root(root);
4147         if (!sb->s_root) {
4148                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4149                 ret = -ENOMEM;
4150                 goto failed_mount4;
4151         }
4152
4153         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
4154                 sb->s_flags |= MS_RDONLY;
4155
4156         /* determine the minimum size of new large inodes, if present */
4157         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4158                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4159                                                      EXT4_GOOD_OLD_INODE_SIZE;
4160                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
4161                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
4162                         if (sbi->s_want_extra_isize <
4163                             le16_to_cpu(es->s_want_extra_isize))
4164                                 sbi->s_want_extra_isize =
4165                                         le16_to_cpu(es->s_want_extra_isize);
4166                         if (sbi->s_want_extra_isize <
4167                             le16_to_cpu(es->s_min_extra_isize))
4168                                 sbi->s_want_extra_isize =
4169                                         le16_to_cpu(es->s_min_extra_isize);
4170                 }
4171         }
4172         /* Check if enough inode space is available */
4173         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
4174                                                         sbi->s_inode_size) {
4175                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4176                                                        EXT4_GOOD_OLD_INODE_SIZE;
4177                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
4178                          "available");
4179         }
4180
4181         err = ext4_reserve_clusters(sbi, ext4_calculate_resv_clusters(sb));
4182         if (err) {
4183                 ext4_msg(sb, KERN_ERR, "failed to reserve %llu clusters for "
4184                          "reserved pool", ext4_calculate_resv_clusters(sb));
4185                 goto failed_mount4a;
4186         }
4187
4188         err = ext4_setup_system_zone(sb);
4189         if (err) {
4190                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4191                          "zone (%d)", err);
4192                 goto failed_mount4a;
4193         }
4194
4195         ext4_ext_init(sb);
4196         err = ext4_mb_init(sb);
4197         if (err) {
4198                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4199                          err);
4200                 goto failed_mount5;
4201         }
4202
4203         block = ext4_count_free_clusters(sb);
4204         ext4_free_blocks_count_set(sbi->s_es,
4205                                    EXT4_C2B(sbi, block));
4206         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4207                                   GFP_KERNEL);
4208         if (!err) {
4209                 unsigned long freei = ext4_count_free_inodes(sb);
4210                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4211                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4212                                           GFP_KERNEL);
4213         }
4214         if (!err)
4215                 err = percpu_counter_init(&sbi->s_dirs_counter,
4216                                           ext4_count_dirs(sb), GFP_KERNEL);
4217         if (!err)
4218                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4219                                           GFP_KERNEL);
4220         if (err) {
4221                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4222                 goto failed_mount6;
4223         }
4224
4225         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
4226                 if (!ext4_fill_flex_info(sb)) {
4227                         ext4_msg(sb, KERN_ERR,
4228                                "unable to initialize "
4229                                "flex_bg meta info!");
4230                         goto failed_mount6;
4231                 }
4232
4233         err = ext4_register_li_request(sb, first_not_zeroed);
4234         if (err)
4235                 goto failed_mount6;
4236
4237         sbi->s_kobj.kset = ext4_kset;
4238         init_completion(&sbi->s_kobj_unregister);
4239         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
4240                                    "%s", sb->s_id);
4241         if (err)
4242                 goto failed_mount7;
4243
4244 #ifdef CONFIG_QUOTA
4245         /* Enable quota usage during mount. */
4246         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
4247             !(sb->s_flags & MS_RDONLY)) {
4248                 err = ext4_enable_quotas(sb);
4249                 if (err)
4250                         goto failed_mount8;
4251         }
4252 #endif  /* CONFIG_QUOTA */
4253
4254         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4255         ext4_orphan_cleanup(sb, es);
4256         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4257         if (needs_recovery) {
4258                 ext4_msg(sb, KERN_INFO, "recovery complete");
4259                 ext4_mark_recovery_complete(sb, es);
4260         }
4261         if (EXT4_SB(sb)->s_journal) {
4262                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4263                         descr = " journalled data mode";
4264                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4265                         descr = " ordered data mode";
4266                 else
4267                         descr = " writeback data mode";
4268         } else
4269                 descr = "out journal";
4270
4271         if (test_opt(sb, DISCARD)) {
4272                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4273                 if (!blk_queue_discard(q))
4274                         ext4_msg(sb, KERN_WARNING,
4275                                  "mounting with \"discard\" option, but "
4276                                  "the device does not support discard");
4277         }
4278
4279         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4280                  "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
4281                  *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4282
4283         if (es->s_error_count)
4284                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4285
4286         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4287         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4288         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4289         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4290
4291         kfree(orig_data);
4292         return 0;
4293
4294 cantfind_ext4:
4295         if (!silent)
4296                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4297         goto failed_mount;
4298
4299 #ifdef CONFIG_QUOTA
4300 failed_mount8:
4301         kobject_del(&sbi->s_kobj);
4302 #endif
4303 failed_mount7:
4304         ext4_unregister_li_request(sb);
4305 failed_mount6:
4306         ext4_mb_release(sb);
4307         if (sbi->s_flex_groups)
4308                 kvfree(sbi->s_flex_groups);
4309         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4310         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4311         percpu_counter_destroy(&sbi->s_dirs_counter);
4312         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4313 failed_mount5:
4314         ext4_ext_release(sb);
4315         ext4_release_system_zone(sb);
4316 failed_mount4a:
4317         dput(sb->s_root);
4318         sb->s_root = NULL;
4319 failed_mount4:
4320         ext4_msg(sb, KERN_ERR, "mount failed");
4321         if (EXT4_SB(sb)->rsv_conversion_wq)
4322                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4323 failed_mount_wq:
4324         if (sbi->s_journal) {
4325                 jbd2_journal_destroy(sbi->s_journal);
4326                 sbi->s_journal = NULL;
4327         }
4328 failed_mount3a:
4329         ext4_es_unregister_shrinker(sbi);
4330 failed_mount3:
4331         del_timer_sync(&sbi->s_err_report);
4332         if (sbi->s_mmp_tsk)
4333                 kthread_stop(sbi->s_mmp_tsk);
4334 failed_mount2:
4335         for (i = 0; i < db_count; i++)
4336                 brelse(sbi->s_group_desc[i]);
4337         kvfree(sbi->s_group_desc);
4338 failed_mount:
4339         if (sbi->s_chksum_driver)
4340                 crypto_free_shash(sbi->s_chksum_driver);
4341         if (sbi->s_proc) {
4342                 remove_proc_entry("options", sbi->s_proc);
4343                 remove_proc_entry(sb->s_id, ext4_proc_root);
4344         }
4345 #ifdef CONFIG_QUOTA
4346         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4347                 kfree(sbi->s_qf_names[i]);
4348 #endif
4349         ext4_blkdev_remove(sbi);
4350         brelse(bh);
4351 out_fail:
4352         sb->s_fs_info = NULL;
4353         kfree(sbi->s_blockgroup_lock);
4354         kfree(sbi);
4355 out_free_orig:
4356         kfree(orig_data);
4357         return err ? err : ret;
4358 }
4359
4360 /*
4361  * Setup any per-fs journal parameters now.  We'll do this both on
4362  * initial mount, once the journal has been initialised but before we've
4363  * done any recovery; and again on any subsequent remount.
4364  */
4365 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4366 {
4367         struct ext4_sb_info *sbi = EXT4_SB(sb);
4368
4369         journal->j_commit_interval = sbi->s_commit_interval;
4370         journal->j_min_batch_time = sbi->s_min_batch_time;
4371         journal->j_max_batch_time = sbi->s_max_batch_time;
4372
4373         write_lock(&journal->j_state_lock);
4374         if (test_opt(sb, BARRIER))
4375                 journal->j_flags |= JBD2_BARRIER;
4376         else
4377                 journal->j_flags &= ~JBD2_BARRIER;
4378         if (test_opt(sb, DATA_ERR_ABORT))
4379                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4380         else
4381                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4382         write_unlock(&journal->j_state_lock);
4383 }
4384
4385 static journal_t *ext4_get_journal(struct super_block *sb,
4386                                    unsigned int journal_inum)
4387 {
4388         struct inode *journal_inode;
4389         journal_t *journal;
4390
4391         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4392
4393         /* First, test for the existence of a valid inode on disk.  Bad
4394          * things happen if we iget() an unused inode, as the subsequent
4395          * iput() will try to delete it. */
4396
4397         journal_inode = ext4_iget(sb, journal_inum);
4398         if (IS_ERR(journal_inode)) {
4399                 ext4_msg(sb, KERN_ERR, "no journal found");
4400                 return NULL;
4401         }
4402         if (!journal_inode->i_nlink) {
4403                 make_bad_inode(journal_inode);
4404                 iput(journal_inode);
4405                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4406                 return NULL;
4407         }
4408
4409         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4410                   journal_inode, journal_inode->i_size);
4411         if (!S_ISREG(journal_inode->i_mode)) {
4412                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4413                 iput(journal_inode);
4414                 return NULL;
4415         }
4416
4417         journal = jbd2_journal_init_inode(journal_inode);
4418         if (!journal) {
4419                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4420                 iput(journal_inode);
4421                 return NULL;
4422         }
4423         journal->j_private = sb;
4424         ext4_init_journal_params(sb, journal);
4425         return journal;
4426 }
4427
4428 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4429                                        dev_t j_dev)
4430 {
4431         struct buffer_head *bh;
4432         journal_t *journal;
4433         ext4_fsblk_t start;
4434         ext4_fsblk_t len;
4435         int hblock, blocksize;
4436         ext4_fsblk_t sb_block;
4437         unsigned long offset;
4438         struct ext4_super_block *es;
4439         struct block_device *bdev;
4440
4441         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4442
4443         bdev = ext4_blkdev_get(j_dev, sb);
4444         if (bdev == NULL)
4445                 return NULL;
4446
4447         blocksize = sb->s_blocksize;
4448         hblock = bdev_logical_block_size(bdev);
4449         if (blocksize < hblock) {
4450                 ext4_msg(sb, KERN_ERR,
4451                         "blocksize too small for journal device");
4452                 goto out_bdev;
4453         }
4454
4455         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4456         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4457         set_blocksize(bdev, blocksize);
4458         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4459                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4460                        "external journal");
4461                 goto out_bdev;
4462         }
4463
4464         es = (struct ext4_super_block *) (bh->b_data + offset);
4465         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4466             !(le32_to_cpu(es->s_feature_incompat) &
4467               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4468                 ext4_msg(sb, KERN_ERR, "external journal has "
4469                                         "bad superblock");
4470                 brelse(bh);
4471                 goto out_bdev;
4472         }
4473
4474         if ((le32_to_cpu(es->s_feature_ro_compat) &
4475              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4476             es->s_checksum != ext4_superblock_csum(sb, es)) {
4477                 ext4_msg(sb, KERN_ERR, "external journal has "
4478                                        "corrupt superblock");
4479                 brelse(bh);
4480                 goto out_bdev;
4481         }
4482
4483         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4484                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4485                 brelse(bh);
4486                 goto out_bdev;
4487         }
4488
4489         len = ext4_blocks_count(es);
4490         start = sb_block + 1;
4491         brelse(bh);     /* we're done with the superblock */
4492
4493         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4494                                         start, len, blocksize);
4495         if (!journal) {
4496                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4497                 goto out_bdev;
4498         }
4499         journal->j_private = sb;
4500         ll_rw_block(READ | REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4501         wait_on_buffer(journal->j_sb_buffer);
4502         if (!buffer_uptodate(journal->j_sb_buffer)) {
4503                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4504                 goto out_journal;
4505         }
4506         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4507                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4508                                         "user (unsupported) - %d",
4509                         be32_to_cpu(journal->j_superblock->s_nr_users));
4510                 goto out_journal;
4511         }
4512         EXT4_SB(sb)->journal_bdev = bdev;
4513         ext4_init_journal_params(sb, journal);
4514         return journal;
4515
4516 out_journal:
4517         jbd2_journal_destroy(journal);
4518 out_bdev:
4519         ext4_blkdev_put(bdev);
4520         return NULL;
4521 }
4522
4523 static int ext4_load_journal(struct super_block *sb,
4524                              struct ext4_super_block *es,
4525                              unsigned long journal_devnum)
4526 {
4527         journal_t *journal;
4528         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4529         dev_t journal_dev;
4530         int err = 0;
4531         int really_read_only;
4532
4533         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4534
4535         if (journal_devnum &&
4536             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4537                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4538                         "numbers have changed");
4539                 journal_dev = new_decode_dev(journal_devnum);
4540         } else
4541                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4542
4543         really_read_only = bdev_read_only(sb->s_bdev);
4544
4545         /*
4546          * Are we loading a blank journal or performing recovery after a
4547          * crash?  For recovery, we need to check in advance whether we
4548          * can get read-write access to the device.
4549          */
4550         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4551                 if (sb->s_flags & MS_RDONLY) {
4552                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4553                                         "required on readonly filesystem");
4554                         if (really_read_only) {
4555                                 ext4_msg(sb, KERN_ERR, "write access "
4556                                         "unavailable, cannot proceed");
4557                                 return -EROFS;
4558                         }
4559                         ext4_msg(sb, KERN_INFO, "write access will "
4560                                "be enabled during recovery");
4561                 }
4562         }
4563
4564         if (journal_inum && journal_dev) {
4565                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4566                        "and inode journals!");
4567                 return -EINVAL;
4568         }
4569
4570         if (journal_inum) {
4571                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4572                         return -EINVAL;
4573         } else {
4574                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4575                         return -EINVAL;
4576         }
4577
4578         if (!(journal->j_flags & JBD2_BARRIER))
4579                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4580
4581         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4582                 err = jbd2_journal_wipe(journal, !really_read_only);
4583         if (!err) {
4584                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4585                 if (save)
4586                         memcpy(save, ((char *) es) +
4587                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4588                 err = jbd2_journal_load(journal);
4589                 if (save)
4590                         memcpy(((char *) es) + EXT4_S_ERR_START,
4591                                save, EXT4_S_ERR_LEN);
4592                 kfree(save);
4593         }
4594
4595         if (err) {
4596                 ext4_msg(sb, KERN_ERR, "error loading journal");
4597                 jbd2_journal_destroy(journal);
4598                 return err;
4599         }
4600
4601         EXT4_SB(sb)->s_journal = journal;
4602         ext4_clear_journal_err(sb, es);
4603
4604         if (!really_read_only && journal_devnum &&
4605             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4606                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4607
4608                 /* Make sure we flush the recovery flag to disk. */
4609                 ext4_commit_super(sb, 1);
4610         }
4611
4612         return 0;
4613 }
4614
4615 static int ext4_commit_super(struct super_block *sb, int sync)
4616 {
4617         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4618         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4619         int error = 0;
4620
4621         if (!sbh)
4622                 return error;
4623         if (buffer_write_io_error(sbh)) {
4624                 /*
4625                  * Oh, dear.  A previous attempt to write the
4626                  * superblock failed.  This could happen because the
4627                  * USB device was yanked out.  Or it could happen to
4628                  * be a transient write error and maybe the block will
4629                  * be remapped.  Nothing we can do but to retry the
4630                  * write and hope for the best.
4631                  */
4632                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4633                        "superblock detected");
4634                 clear_buffer_write_io_error(sbh);
4635                 set_buffer_uptodate(sbh);
4636         }
4637         /*
4638          * If the file system is mounted read-only, don't update the
4639          * superblock write time.  This avoids updating the superblock
4640          * write time when we are mounting the root file system
4641          * read/only but we need to replay the journal; at that point,
4642          * for people who are east of GMT and who make their clock
4643          * tick in localtime for Windows bug-for-bug compatibility,
4644          * the clock is set in the future, and this will cause e2fsck
4645          * to complain and force a full file system check.
4646          */
4647         if (!(sb->s_flags & MS_RDONLY))
4648                 es->s_wtime = cpu_to_le32(get_seconds());
4649         if (sb->s_bdev->bd_part)
4650                 es->s_kbytes_written =
4651                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4652                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4653                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4654         else
4655                 es->s_kbytes_written =
4656                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4657         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4658                 ext4_free_blocks_count_set(es,
4659                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4660                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4661         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4662                 es->s_free_inodes_count =
4663                         cpu_to_le32(percpu_counter_sum_positive(
4664                                 &EXT4_SB(sb)->s_freeinodes_counter));
4665         BUFFER_TRACE(sbh, "marking dirty");
4666         ext4_superblock_csum_set(sb);
4667         mark_buffer_dirty(sbh);
4668         if (sync) {
4669                 error = sync_dirty_buffer(sbh);
4670                 if (error)
4671                         return error;
4672
4673                 error = buffer_write_io_error(sbh);
4674                 if (error) {
4675                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4676                                "superblock");
4677                         clear_buffer_write_io_error(sbh);
4678                         set_buffer_uptodate(sbh);
4679                 }
4680         }
4681         return error;
4682 }
4683
4684 /*
4685  * Have we just finished recovery?  If so, and if we are mounting (or
4686  * remounting) the filesystem readonly, then we will end up with a
4687  * consistent fs on disk.  Record that fact.
4688  */
4689 static void ext4_mark_recovery_complete(struct super_block *sb,
4690                                         struct ext4_super_block *es)
4691 {
4692         journal_t *journal = EXT4_SB(sb)->s_journal;
4693
4694         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4695                 BUG_ON(journal != NULL);
4696                 return;
4697         }
4698         jbd2_journal_lock_updates(journal);
4699         if (jbd2_journal_flush(journal) < 0)
4700                 goto out;
4701
4702         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4703             sb->s_flags & MS_RDONLY) {
4704                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4705                 ext4_commit_super(sb, 1);
4706         }
4707
4708 out:
4709         jbd2_journal_unlock_updates(journal);
4710 }
4711
4712 /*
4713  * If we are mounting (or read-write remounting) a filesystem whose journal
4714  * has recorded an error from a previous lifetime, move that error to the
4715  * main filesystem now.
4716  */
4717 static void ext4_clear_journal_err(struct super_block *sb,
4718                                    struct ext4_super_block *es)
4719 {
4720         journal_t *journal;
4721         int j_errno;
4722         const char *errstr;
4723
4724         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4725
4726         journal = EXT4_SB(sb)->s_journal;
4727
4728         /*
4729          * Now check for any error status which may have been recorded in the
4730          * journal by a prior ext4_error() or ext4_abort()
4731          */
4732
4733         j_errno = jbd2_journal_errno(journal);
4734         if (j_errno) {
4735                 char nbuf[16];
4736
4737                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4738                 ext4_warning(sb, "Filesystem error recorded "
4739                              "from previous mount: %s", errstr);
4740                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4741
4742                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4743                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4744                 ext4_commit_super(sb, 1);
4745
4746                 jbd2_journal_clear_err(journal);
4747                 jbd2_journal_update_sb_errno(journal);
4748         }
4749 }
4750
4751 /*
4752  * Force the running and committing transactions to commit,
4753  * and wait on the commit.
4754  */
4755 int ext4_force_commit(struct super_block *sb)
4756 {
4757         journal_t *journal;
4758
4759         if (sb->s_flags & MS_RDONLY)
4760                 return 0;
4761
4762         journal = EXT4_SB(sb)->s_journal;
4763         return ext4_journal_force_commit(journal);
4764 }
4765
4766 static int ext4_sync_fs(struct super_block *sb, int wait)
4767 {
4768         int ret = 0;
4769         tid_t target;
4770         bool needs_barrier = false;
4771         struct ext4_sb_info *sbi = EXT4_SB(sb);
4772
4773         trace_ext4_sync_fs(sb, wait);
4774         flush_workqueue(sbi->rsv_conversion_wq);
4775         /*
4776          * Writeback quota in non-journalled quota case - journalled quota has
4777          * no dirty dquots
4778          */
4779         dquot_writeback_dquots(sb, -1);
4780         /*
4781          * Data writeback is possible w/o journal transaction, so barrier must
4782          * being sent at the end of the function. But we can skip it if
4783          * transaction_commit will do it for us.
4784          */
4785         if (sbi->s_journal) {
4786                 target = jbd2_get_latest_transaction(sbi->s_journal);
4787                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
4788                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
4789                         needs_barrier = true;
4790
4791                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4792                         if (wait)
4793                                 ret = jbd2_log_wait_commit(sbi->s_journal,
4794                                                            target);
4795                 }
4796         } else if (wait && test_opt(sb, BARRIER))
4797                 needs_barrier = true;
4798         if (needs_barrier) {
4799                 int err;
4800                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4801                 if (!ret)
4802                         ret = err;
4803         }
4804
4805         return ret;
4806 }
4807
4808 /*
4809  * LVM calls this function before a (read-only) snapshot is created.  This
4810  * gives us a chance to flush the journal completely and mark the fs clean.
4811  *
4812  * Note that only this function cannot bring a filesystem to be in a clean
4813  * state independently. It relies on upper layer to stop all data & metadata
4814  * modifications.
4815  */
4816 static int ext4_freeze(struct super_block *sb)
4817 {
4818         int error = 0;
4819         journal_t *journal;
4820
4821         if (sb->s_flags & MS_RDONLY)
4822                 return 0;
4823
4824         journal = EXT4_SB(sb)->s_journal;
4825
4826         if (journal) {
4827                 /* Now we set up the journal barrier. */
4828                 jbd2_journal_lock_updates(journal);
4829
4830                 /*
4831                  * Don't clear the needs_recovery flag if we failed to
4832                  * flush the journal.
4833                  */
4834                 error = jbd2_journal_flush(journal);
4835                 if (error < 0)
4836                         goto out;
4837         }
4838
4839         /* Journal blocked and flushed, clear needs_recovery flag. */
4840         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4841         error = ext4_commit_super(sb, 1);
4842 out:
4843         if (journal)
4844                 /* we rely on upper layer to stop further updates */
4845                 jbd2_journal_unlock_updates(journal);
4846         return error;
4847 }
4848
4849 /*
4850  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4851  * flag here, even though the filesystem is not technically dirty yet.
4852  */
4853 static int ext4_unfreeze(struct super_block *sb)
4854 {
4855         if (sb->s_flags & MS_RDONLY)
4856                 return 0;
4857
4858         /* Reset the needs_recovery flag before the fs is unlocked. */
4859         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4860         ext4_commit_super(sb, 1);
4861         return 0;
4862 }
4863
4864 /*
4865  * Structure to save mount options for ext4_remount's benefit
4866  */
4867 struct ext4_mount_options {
4868         unsigned long s_mount_opt;
4869         unsigned long s_mount_opt2;
4870         kuid_t s_resuid;
4871         kgid_t s_resgid;
4872         unsigned long s_commit_interval;
4873         u32 s_min_batch_time, s_max_batch_time;
4874 #ifdef CONFIG_QUOTA
4875         int s_jquota_fmt;
4876         char *s_qf_names[EXT4_MAXQUOTAS];
4877 #endif
4878 };
4879
4880 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4881 {
4882         struct ext4_super_block *es;
4883         struct ext4_sb_info *sbi = EXT4_SB(sb);
4884         unsigned long old_sb_flags;
4885         struct ext4_mount_options old_opts;
4886         int enable_quota = 0;
4887         ext4_group_t g;
4888         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4889         int err = 0;
4890 #ifdef CONFIG_QUOTA
4891         int i, j;
4892 #endif
4893         char *orig_data = kstrdup(data, GFP_KERNEL);
4894
4895         /* Store the original options */
4896         old_sb_flags = sb->s_flags;
4897         old_opts.s_mount_opt = sbi->s_mount_opt;
4898         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4899         old_opts.s_resuid = sbi->s_resuid;
4900         old_opts.s_resgid = sbi->s_resgid;
4901         old_opts.s_commit_interval = sbi->s_commit_interval;
4902         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4903         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4904 #ifdef CONFIG_QUOTA
4905         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4906         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4907                 if (sbi->s_qf_names[i]) {
4908                         old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
4909                                                          GFP_KERNEL);
4910                         if (!old_opts.s_qf_names[i]) {
4911                                 for (j = 0; j < i; j++)
4912                                         kfree(old_opts.s_qf_names[j]);
4913                                 kfree(orig_data);
4914                                 return -ENOMEM;
4915                         }
4916                 } else
4917                         old_opts.s_qf_names[i] = NULL;
4918 #endif
4919         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4920                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4921
4922         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4923                 err = -EINVAL;
4924                 goto restore_opts;
4925         }
4926
4927         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
4928             test_opt(sb, JOURNAL_CHECKSUM)) {
4929                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
4930                          "during remount not supported; ignoring");
4931                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
4932         }
4933
4934         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4935                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4936                         ext4_msg(sb, KERN_ERR, "can't mount with "
4937                                  "both data=journal and delalloc");
4938                         err = -EINVAL;
4939                         goto restore_opts;
4940                 }
4941                 if (test_opt(sb, DIOREAD_NOLOCK)) {
4942                         ext4_msg(sb, KERN_ERR, "can't mount with "
4943                                  "both data=journal and dioread_nolock");
4944                         err = -EINVAL;
4945                         goto restore_opts;
4946                 }
4947                 if (test_opt(sb, DAX)) {
4948                         ext4_msg(sb, KERN_ERR, "can't mount with "
4949                                  "both data=journal and dax");
4950                         err = -EINVAL;
4951                         goto restore_opts;
4952                 }
4953         }
4954
4955         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
4956                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
4957                         "dax flag with busy inodes while remounting");
4958                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
4959         }
4960
4961         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4962                 ext4_abort(sb, "Abort forced by user");
4963
4964         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4965                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4966
4967         es = sbi->s_es;
4968
4969         if (sbi->s_journal) {
4970                 ext4_init_journal_params(sb, sbi->s_journal);
4971                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4972         }
4973
4974         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4975                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4976                         err = -EROFS;
4977                         goto restore_opts;
4978                 }
4979
4980                 if (*flags & MS_RDONLY) {
4981                         err = sync_filesystem(sb);
4982                         if (err < 0)
4983                                 goto restore_opts;
4984                         err = dquot_suspend(sb, -1);
4985                         if (err < 0)
4986                                 goto restore_opts;
4987
4988                         /*
4989                          * First of all, the unconditional stuff we have to do
4990                          * to disable replay of the journal when we next remount
4991                          */
4992                         sb->s_flags |= MS_RDONLY;
4993
4994                         /*
4995                          * OK, test if we are remounting a valid rw partition
4996                          * readonly, and if so set the rdonly flag and then
4997                          * mark the partition as valid again.
4998                          */
4999                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5000                             (sbi->s_mount_state & EXT4_VALID_FS))
5001                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5002
5003                         if (sbi->s_journal)
5004                                 ext4_mark_recovery_complete(sb, es);
5005                 } else {
5006                         /* Make sure we can mount this feature set readwrite */
5007                         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
5008                                         EXT4_FEATURE_RO_COMPAT_READONLY) ||
5009                             !ext4_feature_set_ok(sb, 0)) {
5010                                 err = -EROFS;
5011                                 goto restore_opts;
5012                         }
5013                         /*
5014                          * Make sure the group descriptor checksums
5015                          * are sane.  If they aren't, refuse to remount r/w.
5016                          */
5017                         for (g = 0; g < sbi->s_groups_count; g++) {
5018                                 struct ext4_group_desc *gdp =
5019                                         ext4_get_group_desc(sb, g, NULL);
5020
5021                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5022                                         ext4_msg(sb, KERN_ERR,
5023                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5024                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
5025                                                le16_to_cpu(gdp->bg_checksum));
5026                                         err = -EINVAL;
5027                                         goto restore_opts;
5028                                 }
5029                         }
5030
5031                         /*
5032                          * If we have an unprocessed orphan list hanging
5033                          * around from a previously readonly bdev mount,
5034                          * require a full umount/remount for now.
5035                          */
5036                         if (es->s_last_orphan) {
5037                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5038                                        "remount RDWR because of unprocessed "
5039                                        "orphan inode list.  Please "
5040                                        "umount/remount instead");
5041                                 err = -EINVAL;
5042                                 goto restore_opts;
5043                         }
5044
5045                         /*
5046                          * Mounting a RDONLY partition read-write, so reread
5047                          * and store the current valid flag.  (It may have
5048                          * been changed by e2fsck since we originally mounted
5049                          * the partition.)
5050                          */
5051                         if (sbi->s_journal)
5052                                 ext4_clear_journal_err(sb, es);
5053                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5054                         if (!ext4_setup_super(sb, es, 0))
5055                                 sb->s_flags &= ~MS_RDONLY;
5056                         if (EXT4_HAS_INCOMPAT_FEATURE(sb,
5057                                                      EXT4_FEATURE_INCOMPAT_MMP))
5058                                 if (ext4_multi_mount_protect(sb,
5059                                                 le64_to_cpu(es->s_mmp_block))) {
5060                                         err = -EROFS;
5061                                         goto restore_opts;
5062                                 }
5063                         enable_quota = 1;
5064                 }
5065         }
5066
5067         /*
5068          * Reinitialize lazy itable initialization thread based on
5069          * current settings
5070          */
5071         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
5072                 ext4_unregister_li_request(sb);
5073         else {
5074                 ext4_group_t first_not_zeroed;
5075                 first_not_zeroed = ext4_has_uninit_itable(sb);
5076                 ext4_register_li_request(sb, first_not_zeroed);
5077         }
5078
5079         ext4_setup_system_zone(sb);
5080         if (sbi->s_journal == NULL && !(old_sb_flags & MS_RDONLY))
5081                 ext4_commit_super(sb, 1);
5082
5083 #ifdef CONFIG_QUOTA
5084         /* Release old quota file names */
5085         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5086                 kfree(old_opts.s_qf_names[i]);
5087         if (enable_quota) {
5088                 if (sb_any_quota_suspended(sb))
5089                         dquot_resume(sb, -1);
5090                 else if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
5091                                         EXT4_FEATURE_RO_COMPAT_QUOTA)) {
5092                         err = ext4_enable_quotas(sb);
5093                         if (err)
5094                                 goto restore_opts;
5095                 }
5096         }
5097 #endif
5098
5099         *flags = (*flags & ~MS_LAZYTIME) | (sb->s_flags & MS_LAZYTIME);
5100         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5101         kfree(orig_data);
5102         return 0;
5103
5104 restore_opts:
5105         sb->s_flags = old_sb_flags;
5106         sbi->s_mount_opt = old_opts.s_mount_opt;
5107         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5108         sbi->s_resuid = old_opts.s_resuid;
5109         sbi->s_resgid = old_opts.s_resgid;
5110         sbi->s_commit_interval = old_opts.s_commit_interval;
5111         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5112         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5113 #ifdef CONFIG_QUOTA
5114         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5115         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5116                 kfree(sbi->s_qf_names[i]);
5117                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
5118         }
5119 #endif
5120         kfree(orig_data);
5121         return err;
5122 }
5123
5124 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5125 {
5126         struct super_block *sb = dentry->d_sb;
5127         struct ext4_sb_info *sbi = EXT4_SB(sb);
5128         struct ext4_super_block *es = sbi->s_es;
5129         ext4_fsblk_t overhead = 0, resv_blocks;
5130         u64 fsid;
5131         s64 bfree;
5132         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5133
5134         if (!test_opt(sb, MINIX_DF))
5135                 overhead = sbi->s_overhead;
5136
5137         buf->f_type = EXT4_SUPER_MAGIC;
5138         buf->f_bsize = sb->s_blocksize;
5139         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5140         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5141                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5142         /* prevent underflow in case that few free space is available */
5143         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5144         buf->f_bavail = buf->f_bfree -
5145                         (ext4_r_blocks_count(es) + resv_blocks);
5146         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5147                 buf->f_bavail = 0;
5148         buf->f_files = le32_to_cpu(es->s_inodes_count);
5149         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5150         buf->f_namelen = EXT4_NAME_LEN;
5151         fsid = le64_to_cpup((void *)es->s_uuid) ^
5152                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5153         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5154         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5155
5156         return 0;
5157 }
5158
5159 /* Helper function for writing quotas on sync - we need to start transaction
5160  * before quota file is locked for write. Otherwise the are possible deadlocks:
5161  * Process 1                         Process 2
5162  * ext4_create()                     quota_sync()
5163  *   jbd2_journal_start()                  write_dquot()
5164  *   dquot_initialize()                         down(dqio_mutex)
5165  *     down(dqio_mutex)                    jbd2_journal_start()
5166  *
5167  */
5168
5169 #ifdef CONFIG_QUOTA
5170
5171 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5172 {
5173         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5174 }
5175
5176 static int ext4_write_dquot(struct dquot *dquot)
5177 {
5178         int ret, err;
5179         handle_t *handle;
5180         struct inode *inode;
5181
5182         inode = dquot_to_inode(dquot);
5183         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5184                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5185         if (IS_ERR(handle))
5186                 return PTR_ERR(handle);
5187         ret = dquot_commit(dquot);
5188         err = ext4_journal_stop(handle);
5189         if (!ret)
5190                 ret = err;
5191         return ret;
5192 }
5193
5194 static int ext4_acquire_dquot(struct dquot *dquot)
5195 {
5196         int ret, err;
5197         handle_t *handle;
5198
5199         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5200                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5201         if (IS_ERR(handle))
5202                 return PTR_ERR(handle);
5203         ret = dquot_acquire(dquot);
5204         err = ext4_journal_stop(handle);
5205         if (!ret)
5206                 ret = err;
5207         return ret;
5208 }
5209
5210 static int ext4_release_dquot(struct dquot *dquot)
5211 {
5212         int ret, err;
5213         handle_t *handle;
5214
5215         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5216                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5217         if (IS_ERR(handle)) {
5218                 /* Release dquot anyway to avoid endless cycle in dqput() */
5219                 dquot_release(dquot);
5220                 return PTR_ERR(handle);
5221         }
5222         ret = dquot_release(dquot);
5223         err = ext4_journal_stop(handle);
5224         if (!ret)
5225                 ret = err;
5226         return ret;
5227 }
5228
5229 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5230 {
5231         struct super_block *sb = dquot->dq_sb;
5232         struct ext4_sb_info *sbi = EXT4_SB(sb);
5233
5234         /* Are we journaling quotas? */
5235         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) ||
5236             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5237                 dquot_mark_dquot_dirty(dquot);
5238                 return ext4_write_dquot(dquot);
5239         } else {
5240                 return dquot_mark_dquot_dirty(dquot);
5241         }
5242 }
5243
5244 static int ext4_write_info(struct super_block *sb, int type)
5245 {
5246         int ret, err;
5247         handle_t *handle;
5248
5249         /* Data block + inode block */
5250         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5251         if (IS_ERR(handle))
5252                 return PTR_ERR(handle);
5253         ret = dquot_commit_info(sb, type);
5254         err = ext4_journal_stop(handle);
5255         if (!ret)
5256                 ret = err;
5257         return ret;
5258 }
5259
5260 /*
5261  * Turn on quotas during mount time - we need to find
5262  * the quota file and such...
5263  */
5264 static int ext4_quota_on_mount(struct super_block *sb, int type)
5265 {
5266         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
5267                                         EXT4_SB(sb)->s_jquota_fmt, type);
5268 }
5269
5270 /*
5271  * Standard function to be called on quota_on
5272  */
5273 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5274                          struct path *path)
5275 {
5276         int err;
5277
5278         if (!test_opt(sb, QUOTA))
5279                 return -EINVAL;
5280
5281         /* Quotafile not on the same filesystem? */
5282         if (path->dentry->d_sb != sb)
5283                 return -EXDEV;
5284         /* Journaling quota? */
5285         if (EXT4_SB(sb)->s_qf_names[type]) {
5286                 /* Quotafile not in fs root? */
5287                 if (path->dentry->d_parent != sb->s_root)
5288                         ext4_msg(sb, KERN_WARNING,
5289                                 "Quota file not on filesystem root. "
5290                                 "Journaled quota will not work");
5291         }
5292
5293         /*
5294          * When we journal data on quota file, we have to flush journal to see
5295          * all updates to the file when we bypass pagecache...
5296          */
5297         if (EXT4_SB(sb)->s_journal &&
5298             ext4_should_journal_data(d_inode(path->dentry))) {
5299                 /*
5300                  * We don't need to lock updates but journal_flush() could
5301                  * otherwise be livelocked...
5302                  */
5303                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5304                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5305                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5306                 if (err)
5307                         return err;
5308         }
5309
5310         return dquot_quota_on(sb, type, format_id, path);
5311 }
5312
5313 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5314                              unsigned int flags)
5315 {
5316         int err;
5317         struct inode *qf_inode;
5318         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5319                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5320                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
5321         };
5322
5323         BUG_ON(!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA));
5324
5325         if (!qf_inums[type])
5326                 return -EPERM;
5327
5328         qf_inode = ext4_iget(sb, qf_inums[type]);
5329         if (IS_ERR(qf_inode)) {
5330                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5331                 return PTR_ERR(qf_inode);
5332         }
5333
5334         /* Don't account quota for quota files to avoid recursion */
5335         qf_inode->i_flags |= S_NOQUOTA;
5336         err = dquot_enable(qf_inode, type, format_id, flags);
5337         iput(qf_inode);
5338
5339         return err;
5340 }
5341
5342 /* Enable usage tracking for all quota types. */
5343 static int ext4_enable_quotas(struct super_block *sb)
5344 {
5345         int type, err = 0;
5346         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5347                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5348                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
5349         };
5350
5351         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
5352         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5353                 if (qf_inums[type]) {
5354                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5355                                                 DQUOT_USAGE_ENABLED);
5356                         if (err) {
5357                                 ext4_warning(sb,
5358                                         "Failed to enable quota tracking "
5359                                         "(type=%d, err=%d). Please run "
5360                                         "e2fsck to fix.", type, err);
5361                                 return err;
5362                         }
5363                 }
5364         }
5365         return 0;
5366 }
5367
5368 static int ext4_quota_off(struct super_block *sb, int type)
5369 {
5370         struct inode *inode = sb_dqopt(sb)->files[type];
5371         handle_t *handle;
5372
5373         /* Force all delayed allocation blocks to be allocated.
5374          * Caller already holds s_umount sem */
5375         if (test_opt(sb, DELALLOC))
5376                 sync_filesystem(sb);
5377
5378         if (!inode)
5379                 goto out;
5380
5381         /* Update modification times of quota files when userspace can
5382          * start looking at them */
5383         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5384         if (IS_ERR(handle))
5385                 goto out;
5386         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
5387         ext4_mark_inode_dirty(handle, inode);
5388         ext4_journal_stop(handle);
5389
5390 out:
5391         return dquot_quota_off(sb, type);
5392 }
5393
5394 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5395  * acquiring the locks... As quota files are never truncated and quota code
5396  * itself serializes the operations (and no one else should touch the files)
5397  * we don't have to be afraid of races */
5398 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5399                                size_t len, loff_t off)
5400 {
5401         struct inode *inode = sb_dqopt(sb)->files[type];
5402         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5403         int offset = off & (sb->s_blocksize - 1);
5404         int tocopy;
5405         size_t toread;
5406         struct buffer_head *bh;
5407         loff_t i_size = i_size_read(inode);
5408
5409         if (off > i_size)
5410                 return 0;
5411         if (off+len > i_size)
5412                 len = i_size-off;
5413         toread = len;
5414         while (toread > 0) {
5415                 tocopy = sb->s_blocksize - offset < toread ?
5416                                 sb->s_blocksize - offset : toread;
5417                 bh = ext4_bread(NULL, inode, blk, 0);
5418                 if (IS_ERR(bh))
5419                         return PTR_ERR(bh);
5420                 if (!bh)        /* A hole? */
5421                         memset(data, 0, tocopy);
5422                 else
5423                         memcpy(data, bh->b_data+offset, tocopy);
5424                 brelse(bh);
5425                 offset = 0;
5426                 toread -= tocopy;
5427                 data += tocopy;
5428                 blk++;
5429         }
5430         return len;
5431 }
5432
5433 /* Write to quotafile (we know the transaction is already started and has
5434  * enough credits) */
5435 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5436                                 const char *data, size_t len, loff_t off)
5437 {
5438         struct inode *inode = sb_dqopt(sb)->files[type];
5439         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5440         int err, offset = off & (sb->s_blocksize - 1);
5441         int retries = 0;
5442         struct buffer_head *bh;
5443         handle_t *handle = journal_current_handle();
5444
5445         if (EXT4_SB(sb)->s_journal && !handle) {
5446                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5447                         " cancelled because transaction is not started",
5448                         (unsigned long long)off, (unsigned long long)len);
5449                 return -EIO;
5450         }
5451         /*
5452          * Since we account only one data block in transaction credits,
5453          * then it is impossible to cross a block boundary.
5454          */
5455         if (sb->s_blocksize - offset < len) {
5456                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5457                         " cancelled because not block aligned",
5458                         (unsigned long long)off, (unsigned long long)len);
5459                 return -EIO;
5460         }
5461
5462         do {
5463                 bh = ext4_bread(handle, inode, blk,
5464                                 EXT4_GET_BLOCKS_CREATE |
5465                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5466         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5467                  ext4_should_retry_alloc(inode->i_sb, &retries));
5468         if (IS_ERR(bh))
5469                 return PTR_ERR(bh);
5470         if (!bh)
5471                 goto out;
5472         BUFFER_TRACE(bh, "get write access");
5473         err = ext4_journal_get_write_access(handle, bh);
5474         if (err) {
5475                 brelse(bh);
5476                 return err;
5477         }
5478         lock_buffer(bh);
5479         memcpy(bh->b_data+offset, data, len);
5480         flush_dcache_page(bh->b_page);
5481         unlock_buffer(bh);
5482         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5483         brelse(bh);
5484 out:
5485         if (inode->i_size < off + len) {
5486                 i_size_write(inode, off + len);
5487                 EXT4_I(inode)->i_disksize = inode->i_size;
5488                 ext4_mark_inode_dirty(handle, inode);
5489         }
5490         return len;
5491 }
5492
5493 #endif
5494
5495 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5496                        const char *dev_name, void *data)
5497 {
5498         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5499 }
5500
5501 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5502 static inline void register_as_ext2(void)
5503 {
5504         int err = register_filesystem(&ext2_fs_type);
5505         if (err)
5506                 printk(KERN_WARNING
5507                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5508 }
5509
5510 static inline void unregister_as_ext2(void)
5511 {
5512         unregister_filesystem(&ext2_fs_type);
5513 }
5514
5515 static inline int ext2_feature_set_ok(struct super_block *sb)
5516 {
5517         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
5518                 return 0;
5519         if (sb->s_flags & MS_RDONLY)
5520                 return 1;
5521         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
5522                 return 0;
5523         return 1;
5524 }
5525 #else
5526 static inline void register_as_ext2(void) { }
5527 static inline void unregister_as_ext2(void) { }
5528 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5529 #endif
5530
5531 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5532 static inline void register_as_ext3(void)
5533 {
5534         int err = register_filesystem(&ext3_fs_type);
5535         if (err)
5536                 printk(KERN_WARNING
5537                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5538 }
5539
5540 static inline void unregister_as_ext3(void)
5541 {
5542         unregister_filesystem(&ext3_fs_type);
5543 }
5544
5545 static inline int ext3_feature_set_ok(struct super_block *sb)
5546 {
5547         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
5548                 return 0;
5549         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
5550                 return 0;
5551         if (sb->s_flags & MS_RDONLY)
5552                 return 1;
5553         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
5554                 return 0;
5555         return 1;
5556 }
5557 #else
5558 static inline void register_as_ext3(void) { }
5559 static inline void unregister_as_ext3(void) { }
5560 static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
5561 #endif
5562
5563 static struct file_system_type ext4_fs_type = {
5564         .owner          = THIS_MODULE,
5565         .name           = "ext4",
5566         .mount          = ext4_mount,
5567         .kill_sb        = kill_block_super,
5568         .fs_flags       = FS_REQUIRES_DEV,
5569 };
5570 MODULE_ALIAS_FS("ext4");
5571
5572 static int __init ext4_init_feat_adverts(void)
5573 {
5574         struct ext4_features *ef;
5575         int ret = -ENOMEM;
5576
5577         ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
5578         if (!ef)
5579                 goto out;
5580
5581         ef->f_kobj.kset = ext4_kset;
5582         init_completion(&ef->f_kobj_unregister);
5583         ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
5584                                    "features");
5585         if (ret) {
5586                 kfree(ef);
5587                 goto out;
5588         }
5589
5590         ext4_feat = ef;
5591         ret = 0;
5592 out:
5593         return ret;
5594 }
5595
5596 static void ext4_exit_feat_adverts(void)
5597 {
5598         kobject_put(&ext4_feat->f_kobj);
5599         wait_for_completion(&ext4_feat->f_kobj_unregister);
5600         kfree(ext4_feat);
5601 }
5602
5603 /* Shared across all ext4 file systems */
5604 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5605 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5606
5607 static int __init ext4_init_fs(void)
5608 {
5609         int i, err;
5610
5611         ext4_li_info = NULL;
5612         mutex_init(&ext4_li_mtx);
5613
5614         /* Build-time check for flags consistency */
5615         ext4_check_flag_values();
5616
5617         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5618                 mutex_init(&ext4__aio_mutex[i]);
5619                 init_waitqueue_head(&ext4__ioend_wq[i]);
5620         }
5621
5622         err = ext4_init_es();
5623         if (err)
5624                 return err;
5625
5626         err = ext4_init_pageio();
5627         if (err)
5628                 goto out7;
5629
5630         err = ext4_init_system_zone();
5631         if (err)
5632                 goto out6;
5633         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
5634         if (!ext4_kset) {
5635                 err = -ENOMEM;
5636                 goto out5;
5637         }
5638         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
5639
5640         err = ext4_init_feat_adverts();
5641         if (err)
5642                 goto out4;
5643
5644         err = ext4_init_mballoc();
5645         if (err)
5646                 goto out2;
5647         else
5648                 ext4_mballoc_ready = 1;
5649         err = init_inodecache();
5650         if (err)
5651                 goto out1;
5652         register_as_ext3();
5653         register_as_ext2();
5654         err = register_filesystem(&ext4_fs_type);
5655         if (err)
5656                 goto out;
5657
5658         return 0;
5659 out:
5660         unregister_as_ext2();
5661         unregister_as_ext3();
5662         destroy_inodecache();
5663 out1:
5664         ext4_mballoc_ready = 0;
5665         ext4_exit_mballoc();
5666 out2:
5667         ext4_exit_feat_adverts();
5668 out4:
5669         if (ext4_proc_root)
5670                 remove_proc_entry("fs/ext4", NULL);
5671         kset_unregister(ext4_kset);
5672 out5:
5673         ext4_exit_system_zone();
5674 out6:
5675         ext4_exit_pageio();
5676 out7:
5677         ext4_exit_es();
5678
5679         return err;
5680 }
5681
5682 static void __exit ext4_exit_fs(void)
5683 {
5684         ext4_exit_crypto();
5685         ext4_destroy_lazyinit_thread();
5686         unregister_as_ext2();
5687         unregister_as_ext3();
5688         unregister_filesystem(&ext4_fs_type);
5689         destroy_inodecache();
5690         ext4_exit_mballoc();
5691         ext4_exit_feat_adverts();
5692         remove_proc_entry("fs/ext4", NULL);
5693         kset_unregister(ext4_kset);
5694         ext4_exit_system_zone();
5695         ext4_exit_pageio();
5696         ext4_exit_es();
5697 }
5698
5699 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5700 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5701 MODULE_LICENSE("GPL");
5702 module_init(ext4_init_fs)
5703 module_exit(ext4_exit_fs)