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/backing-dev.h>
  28 #include <linux/parser.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/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 ext4_lazy_init *ext4_li_info;
  57 static struct mutex ext4_li_mtx;
  58 static int ext4_mballoc_ready;
  59 static struct ratelimit_state ext4_mount_msg_ratelimit;
  60
  61 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  62                              unsigned long journal_devnum);
  63 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  64 static int ext4_commit_super(struct super_block *sb, int sync);
  65 static void ext4_mark_recovery_complete(struct super_block *sb,
  66                                         struct ext4_super_block *es);
  67 static void ext4_clear_journal_err(struct super_block *sb,
  68                                    struct ext4_super_block *es);
  69 static int ext4_sync_fs(struct super_block *sb, int wait);
  70 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  71 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  72 static int ext4_unfreeze(struct super_block *sb);
  73 static int ext4_freeze(struct super_block *sb);
  74 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  75                        const char *dev_name, void *data);
  76 static inline int ext2_feature_set_ok(struct super_block *sb);
  77 static inline int ext3_feature_set_ok(struct super_block *sb);
  78 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  79 static void ext4_destroy_lazyinit_thread(void);
  80 static void ext4_unregister_li_request(struct super_block *sb);
  81 static void ext4_clear_request_list(void);
  82
  83 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
  84 static struct file_system_type ext2_fs_type = {
  85         .owner          = THIS_MODULE,
  86         .name           = "ext2",
  87         .mount          = ext4_mount,
  88         .kill_sb        = kill_block_super,
  89         .fs_flags       = FS_REQUIRES_DEV,
  90 };
  91 MODULE_ALIAS_FS("ext2");
  92 MODULE_ALIAS("ext2");
  93 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
  94 #else
  95 #define IS_EXT2_SB(sb) (0)
  96 #endif
  97
  98
  99 static struct file_system_type ext3_fs_type = {
 100         .owner          = THIS_MODULE,
 101         .name           = "ext3",
 102         .mount          = ext4_mount,
 103         .kill_sb        = kill_block_super,
 104         .fs_flags       = FS_REQUIRES_DEV,
 105 };
 106 MODULE_ALIAS_FS("ext3");
 107 MODULE_ALIAS("ext3");
 108 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 109
 110 static int ext4_verify_csum_type(struct super_block *sb,
 111                                  struct ext4_super_block *es)
 112 {
 113         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 114                                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 115                 return 1;
 116
 117         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 118 }
 119
 120 static __le32 ext4_superblock_csum(struct super_block *sb,
 121                                    struct ext4_super_block *es)
 122 {
 123         struct ext4_sb_info *sbi = EXT4_SB(sb);
 124         int offset = offsetof(struct ext4_super_block, s_checksum);
 125         __u32 csum;
 126
 127         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 128
 129         return cpu_to_le32(csum);
 130 }
 131
 132 static int ext4_superblock_csum_verify(struct super_block *sb,
 133                                        struct ext4_super_block *es)
 134 {
 135         if (!ext4_has_metadata_csum(sb))
 136                 return 1;
 137
 138         return es->s_checksum == ext4_superblock_csum(sb, es);
 139 }
 140
 141 void ext4_superblock_csum_set(struct super_block *sb)
 142 {
 143         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 144
 145         if (!ext4_has_metadata_csum(sb))
 146                 return;
 147
 148         es->s_checksum = ext4_superblock_csum(sb, es);
 149 }
 150
 151 void *ext4_kvmalloc(size_t size, gfp_t flags)
 152 {
 153         void *ret;
 154
 155         ret = kmalloc(size, flags | __GFP_NOWARN);
 156         if (!ret)
 157                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 158         return ret;
 159 }
 160
 161 void *ext4_kvzalloc(size_t size, gfp_t flags)
 162 {
 163         void *ret;
 164
 165         ret = kzalloc(size, flags | __GFP_NOWARN);
 166         if (!ret)
 167                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 168         return ret;
 169 }
 170
 171 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 172                                struct ext4_group_desc *bg)
 173 {
 174         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 175                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 176                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 177 }
 178
 179 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 180                                struct ext4_group_desc *bg)
 181 {
 182         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 183                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 184                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 185 }
 186
 187 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 188                               struct ext4_group_desc *bg)
 189 {
 190         return le32_to_cpu(bg->bg_inode_table_lo) |
 191                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 192                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 193 }
 194
 195 __u32 ext4_free_group_clusters(struct super_block *sb,
 196                                struct ext4_group_desc *bg)
 197 {
 198         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 199                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 200                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 201 }
 202
 203 __u32 ext4_free_inodes_count(struct super_block *sb,
 204                               struct ext4_group_desc *bg)
 205 {
 206         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 207                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 208                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 209 }
 210
 211 __u32 ext4_used_dirs_count(struct super_block *sb,
 212                               struct ext4_group_desc *bg)
 213 {
 214         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 215                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 216                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 217 }
 218
 219 __u32 ext4_itable_unused_count(struct super_block *sb,
 220                               struct ext4_group_desc *bg)
 221 {
 222         return le16_to_cpu(bg->bg_itable_unused_lo) |
 223                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 224                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 225 }
 226
 227 void ext4_block_bitmap_set(struct super_block *sb,
 228                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 229 {
 230         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 231         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 232                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 233 }
 234
 235 void ext4_inode_bitmap_set(struct super_block *sb,
 236                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 237 {
 238         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 239         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 240                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 241 }
 242
 243 void ext4_inode_table_set(struct super_block *sb,
 244                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 245 {
 246         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 247         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 248                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 249 }
 250
 251 void ext4_free_group_clusters_set(struct super_block *sb,
 252                                   struct ext4_group_desc *bg, __u32 count)
 253 {
 254         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 255         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 256                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 257 }
 258
 259 void ext4_free_inodes_set(struct super_block *sb,
 260                           struct ext4_group_desc *bg, __u32 count)
 261 {
 262         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 263         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 264                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 265 }
 266
 267 void ext4_used_dirs_set(struct super_block *sb,
 268                           struct ext4_group_desc *bg, __u32 count)
 269 {
 270         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 271         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 272                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 273 }
 274
 275 void ext4_itable_unused_set(struct super_block *sb,
 276                           struct ext4_group_desc *bg, __u32 count)
 277 {
 278         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 279         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 280                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 281 }
 282
 283
 284 static void __save_error_info(struct super_block *sb, const char *func,
 285                             unsigned int line)
 286 {
 287         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 288
 289         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 290         if (bdev_read_only(sb->s_bdev))
 291                 return;
 292         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 293         es->s_last_error_time = cpu_to_le32(get_seconds());
 294         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 295         es->s_last_error_line = cpu_to_le32(line);
 296         if (!es->s_first_error_time) {
 297                 es->s_first_error_time = es->s_last_error_time;
 298                 strncpy(es->s_first_error_func, func,
 299                         sizeof(es->s_first_error_func));
 300                 es->s_first_error_line = cpu_to_le32(line);
 301                 es->s_first_error_ino = es->s_last_error_ino;
 302                 es->s_first_error_block = es->s_last_error_block;
 303         }
 304         /*
 305          * Start the daily error reporting function if it hasn't been
 306          * started already
 307          */
 308         if (!es->s_error_count)
 309                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 310         le32_add_cpu(&es->s_error_count, 1);
 311 }
 312
 313 static void save_error_info(struct super_block *sb, const char *func,
 314                             unsigned int line)
 315 {
 316         __save_error_info(sb, func, line);
 317         ext4_commit_super(sb, 1);
 318 }
 319
 320 /*
 321  * The del_gendisk() function uninitializes the disk-specific data
 322  * structures, including the bdi structure, without telling anyone
 323  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 324  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 325  * This is a kludge to prevent these oops until we can put in a proper
 326  * hook in del_gendisk() to inform the VFS and file system layers.
 327  */
 328 static int block_device_ejected(struct super_block *sb)
 329 {
 330         struct inode *bd_inode = sb->s_bdev->bd_inode;
 331         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 332
 333         return bdi->dev == NULL;
 334 }
 335
 336 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 337 {
 338         struct super_block              *sb = journal->j_private;
 339         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 340         int                             error = is_journal_aborted(journal);
 341         struct ext4_journal_cb_entry    *jce;
 342
 343         BUG_ON(txn->t_state == T_FINISHED);
 344         spin_lock(&sbi->s_md_lock);
 345         while (!list_empty(&txn->t_private_list)) {
 346                 jce = list_entry(txn->t_private_list.next,
 347                                  struct ext4_journal_cb_entry, jce_list);
 348                 list_del_init(&jce->jce_list);
 349                 spin_unlock(&sbi->s_md_lock);
 350                 jce->jce_func(sb, jce, error);
 351                 spin_lock(&sbi->s_md_lock);
 352         }
 353         spin_unlock(&sbi->s_md_lock);
 354 }
 355
 356 /* Deal with the reporting of failure conditions on a filesystem such as
 357  * inconsistencies detected or read IO failures.
 358  *
 359  * On ext2, we can store the error state of the filesystem in the
 360  * superblock.  That is not possible on ext4, because we may have other
 361  * write ordering constraints on the superblock which prevent us from
 362  * writing it out straight away; and given that the journal is about to
 363  * be aborted, we can't rely on the current, or future, transactions to
 364  * write out the superblock safely.
 365  *
 366  * We'll just use the jbd2_journal_abort() error code to record an error in
 367  * the journal instead.  On recovery, the journal will complain about
 368  * that error until we've noted it down and cleared it.
 369  */
 370
 371 static void ext4_handle_error(struct super_block *sb)
 372 {
 373         if (sb->s_flags & MS_RDONLY)
 374                 return;
 375
 376         if (!test_opt(sb, ERRORS_CONT)) {
 377                 journal_t *journal = EXT4_SB(sb)->s_journal;
 378
 379                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 380                 if (journal)
 381                         jbd2_journal_abort(journal, -EIO);
 382         }
 383         if (test_opt(sb, ERRORS_RO)) {
 384                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 385                 /*
 386                  * Make sure updated value of ->s_mount_flags will be visible
 387                  * before ->s_flags update
 388                  */
 389                 smp_wmb();
 390                 sb->s_flags |= MS_RDONLY;
 391         }
 392         if (test_opt(sb, ERRORS_PANIC))
 393                 panic("EXT4-fs (device %s): panic forced after error\n",
 394                         sb->s_id);
 395 }
 396
 397 #define ext4_error_ratelimit(sb)                                        \
 398                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 399                              "EXT4-fs error")
 400
 401 void __ext4_error(struct super_block *sb, const char *function,
 402                   unsigned int line, const char *fmt, ...)
 403 {
 404         struct va_format vaf;
 405         va_list args;
 406
 407         if (ext4_error_ratelimit(sb)) {
 408                 va_start(args, fmt);
 409                 vaf.fmt = fmt;
 410                 vaf.va = &args;
 411                 printk(KERN_CRIT
 412                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 413                        sb->s_id, function, line, current->comm, &vaf);
 414                 va_end(args);
 415         }
 416         save_error_info(sb, function, line);
 417         ext4_handle_error(sb);
 418 }
 419
 420 void __ext4_error_inode(struct inode *inode, const char *function,
 421                         unsigned int line, ext4_fsblk_t block,
 422                         const char *fmt, ...)
 423 {
 424         va_list args;
 425         struct va_format vaf;
 426         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 427
 428         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 429         es->s_last_error_block = cpu_to_le64(block);
 430         if (ext4_error_ratelimit(inode->i_sb)) {
 431                 va_start(args, fmt);
 432                 vaf.fmt = fmt;
 433                 vaf.va = &args;
 434                 if (block)
 435                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 436                                "inode #%lu: block %llu: comm %s: %pV\n",
 437                                inode->i_sb->s_id, function, line, inode->i_ino,
 438                                block, current->comm, &vaf);
 439                 else
 440                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 441                                "inode #%lu: comm %s: %pV\n",
 442                                inode->i_sb->s_id, function, line, inode->i_ino,
 443                                current->comm, &vaf);
 444                 va_end(args);
 445         }
 446         save_error_info(inode->i_sb, function, line);
 447         ext4_handle_error(inode->i_sb);
 448 }
 449
 450 void __ext4_error_file(struct file *file, const char *function,
 451                        unsigned int line, ext4_fsblk_t block,
 452                        const char *fmt, ...)
 453 {
 454         va_list args;
 455         struct va_format vaf;
 456         struct ext4_super_block *es;
 457         struct inode *inode = file_inode(file);
 458         char pathname[80], *path;
 459
 460         es = EXT4_SB(inode->i_sb)->s_es;
 461         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 462         if (ext4_error_ratelimit(inode->i_sb)) {
 463                 path = file_path(file, pathname, sizeof(pathname));
 464                 if (IS_ERR(path))
 465                         path = "(unknown)";
 466                 va_start(args, fmt);
 467                 vaf.fmt = fmt;
 468                 vaf.va = &args;
 469                 if (block)
 470                         printk(KERN_CRIT
 471                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 472                                "block %llu: comm %s: path %s: %pV\n",
 473                                inode->i_sb->s_id, function, line, inode->i_ino,
 474                                block, current->comm, path, &vaf);
 475                 else
 476                         printk(KERN_CRIT
 477                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 478                                "comm %s: path %s: %pV\n",
 479                                inode->i_sb->s_id, function, line, inode->i_ino,
 480                                current->comm, path, &vaf);
 481                 va_end(args);
 482         }
 483         save_error_info(inode->i_sb, function, line);
 484         ext4_handle_error(inode->i_sb);
 485 }
 486
 487 const char *ext4_decode_error(struct super_block *sb, int errno,
 488                               char nbuf[16])
 489 {
 490         char *errstr = NULL;
 491
 492         switch (errno) {
 493         case -EIO:
 494                 errstr = "IO failure";
 495                 break;
 496         case -ENOMEM:
 497                 errstr = "Out of memory";
 498                 break;
 499         case -EROFS:
 500                 if (!sb || (EXT4_SB(sb)->s_journal &&
 501                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 502                         errstr = "Journal has aborted";
 503                 else
 504                         errstr = "Readonly filesystem";
 505                 break;
 506         default:
 507                 /* If the caller passed in an extra buffer for unknown
 508                  * errors, textualise them now.  Else we just return
 509                  * NULL. */
 510                 if (nbuf) {
 511                         /* Check for truncated error codes... */
 512                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 513                                 errstr = nbuf;
 514                 }
 515                 break;
 516         }
 517
 518         return errstr;
 519 }
 520
 521 /* __ext4_std_error decodes expected errors from journaling functions
 522  * automatically and invokes the appropriate error response.  */
 523
 524 void __ext4_std_error(struct super_block *sb, const char *function,
 525                       unsigned int line, int errno)
 526 {
 527         char nbuf[16];
 528         const char *errstr;
 529
 530         /* Special case: if the error is EROFS, and we're not already
 531          * inside a transaction, then there's really no point in logging
 532          * an error. */
 533         if (errno == -EROFS && journal_current_handle() == NULL &&
 534             (sb->s_flags & MS_RDONLY))
 535                 return;
 536
 537         if (ext4_error_ratelimit(sb)) {
 538                 errstr = ext4_decode_error(sb, errno, nbuf);
 539                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 540                        sb->s_id, function, line, errstr);
 541         }
 542
 543         save_error_info(sb, function, line);
 544         ext4_handle_error(sb);
 545 }
 546
 547 /*
 548  * ext4_abort is a much stronger failure handler than ext4_error.  The
 549  * abort function may be used to deal with unrecoverable failures such
 550  * as journal IO errors or ENOMEM at a critical moment in log management.
 551  *
 552  * We unconditionally force the filesystem into an ABORT|READONLY state,
 553  * unless the error response on the fs has been set to panic in which
 554  * case we take the easy way out and panic immediately.
 555  */
 556
 557 void __ext4_abort(struct super_block *sb, const char *function,
 558                 unsigned int line, const char *fmt, ...)
 559 {
 560         va_list args;
 561
 562         save_error_info(sb, function, line);
 563         va_start(args, fmt);
 564         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 565                function, line);
 566         vprintk(fmt, args);
 567         printk("\n");
 568         va_end(args);
 569
 570         if ((sb->s_flags & MS_RDONLY) == 0) {
 571                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 572                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 573                 /*
 574                  * Make sure updated value of ->s_mount_flags will be visible
 575                  * before ->s_flags update
 576                  */
 577                 smp_wmb();
 578                 sb->s_flags |= MS_RDONLY;
 579                 if (EXT4_SB(sb)->s_journal)
 580                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 581                 save_error_info(sb, function, line);
 582         }
 583         if (test_opt(sb, ERRORS_PANIC))
 584                 panic("EXT4-fs panic from previous error\n");
 585 }
 586
 587 void __ext4_msg(struct super_block *sb,
 588                 const char *prefix, const char *fmt, ...)
 589 {
 590         struct va_format vaf;
 591         va_list args;
 592
 593         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 594                 return;
 595
 596         va_start(args, fmt);
 597         vaf.fmt = fmt;
 598         vaf.va = &args;
 599         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 600         va_end(args);
 601 }
 602
 603 #define ext4_warning_ratelimit(sb)                                      \
 604                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 605                              "EXT4-fs warning")
 606
 607 void __ext4_warning(struct super_block *sb, const char *function,
 608                     unsigned int line, const char *fmt, ...)
 609 {
 610         struct va_format vaf;
 611         va_list args;
 612
 613         if (!ext4_warning_ratelimit(sb))
 614                 return;
 615
 616         va_start(args, fmt);
 617         vaf.fmt = fmt;
 618         vaf.va = &args;
 619         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 620                sb->s_id, function, line, &vaf);
 621         va_end(args);
 622 }
 623
 624 void __ext4_warning_inode(const struct inode *inode, const char *function,
 625                           unsigned int line, const char *fmt, ...)
 626 {
 627         struct va_format vaf;
 628         va_list args;
 629
 630         if (!ext4_warning_ratelimit(inode->i_sb))
 631                 return;
 632
 633         va_start(args, fmt);
 634         vaf.fmt = fmt;
 635         vaf.va = &args;
 636         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 637                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 638                function, line, inode->i_ino, current->comm, &vaf);
 639         va_end(args);
 640 }
 641
 642 void __ext4_grp_locked_error(const char *function, unsigned int line,
 643                              struct super_block *sb, ext4_group_t grp,
 644                              unsigned long ino, ext4_fsblk_t block,
 645                              const char *fmt, ...)
 646 __releases(bitlock)
 647 __acquires(bitlock)
 648 {
 649         struct va_format vaf;
 650         va_list args;
 651         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 652
 653         es->s_last_error_ino = cpu_to_le32(ino);
 654         es->s_last_error_block = cpu_to_le64(block);
 655         __save_error_info(sb, function, line);
 656
 657         if (ext4_error_ratelimit(sb)) {
 658                 va_start(args, fmt);
 659                 vaf.fmt = fmt;
 660                 vaf.va = &args;
 661                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 662                        sb->s_id, function, line, grp);
 663                 if (ino)
 664                         printk(KERN_CONT "inode %lu: ", ino);
 665                 if (block)
 666                         printk(KERN_CONT "block %llu:",
 667                                (unsigned long long) block);
 668                 printk(KERN_CONT "%pV\n", &vaf);
 669                 va_end(args);
 670         }
 671
 672         if (test_opt(sb, ERRORS_CONT)) {
 673                 ext4_commit_super(sb, 0);
 674                 return;
 675         }
 676
 677         ext4_unlock_group(sb, grp);
 678         ext4_handle_error(sb);
 679         /*
 680          * We only get here in the ERRORS_RO case; relocking the group
 681          * may be dangerous, but nothing bad will happen since the
 682          * filesystem will have already been marked read/only and the
 683          * journal has been aborted.  We return 1 as a hint to callers
 684          * who might what to use the return value from
 685          * ext4_grp_locked_error() to distinguish between the
 686          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 687          * aggressively from the ext4 function in question, with a
 688          * more appropriate error code.
 689          */
 690         ext4_lock_group(sb, grp);
 691         return;
 692 }
 693
 694 void ext4_update_dynamic_rev(struct super_block *sb)
 695 {
 696         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 697
 698         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 699                 return;
 700
 701         ext4_warning(sb,
 702                      "updating to rev %d because of new feature flag, "
 703                      "running e2fsck is recommended",
 704                      EXT4_DYNAMIC_REV);
 705
 706         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 707         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 708         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 709         /* leave es->s_feature_*compat flags alone */
 710         /* es->s_uuid will be set by e2fsck if empty */
 711
 712         /*
 713          * The rest of the superblock fields should be zero, and if not it
 714          * means they are likely already in use, so leave them alone.  We
 715          * can leave it up to e2fsck to clean up any inconsistencies there.
 716          */
 717 }
 718
 719 /*
 720  * Open the external journal device
 721  */
 722 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 723 {
 724         struct block_device *bdev;
 725         char b[BDEVNAME_SIZE];
 726
 727         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 728         if (IS_ERR(bdev))
 729                 goto fail;
 730         return bdev;
 731
 732 fail:
 733         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 734                         __bdevname(dev, b), PTR_ERR(bdev));
 735         return NULL;
 736 }
 737
 738 /*
 739  * Release the journal device
 740  */
 741 static void ext4_blkdev_put(struct block_device *bdev)
 742 {
 743         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 744 }
 745
 746 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 747 {
 748         struct block_device *bdev;
 749         bdev = sbi->journal_bdev;
 750         if (bdev) {
 751                 ext4_blkdev_put(bdev);
 752                 sbi->journal_bdev = NULL;
 753         }
 754 }
 755
 756 static inline struct inode *orphan_list_entry(struct list_head *l)
 757 {
 758         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 759 }
 760
 761 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 762 {
 763         struct list_head *l;
 764
 765         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 766                  le32_to_cpu(sbi->s_es->s_last_orphan));
 767
 768         printk(KERN_ERR "sb_info orphan list:\n");
 769         list_for_each(l, &sbi->s_orphan) {
 770                 struct inode *inode = orphan_list_entry(l);
 771                 printk(KERN_ERR "  "
 772                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 773                        inode->i_sb->s_id, inode->i_ino, inode,
 774                        inode->i_mode, inode->i_nlink,
 775                        NEXT_ORPHAN(inode));
 776         }
 777 }
 778
 779 static void ext4_put_super(struct super_block *sb)
 780 {
 781         struct ext4_sb_info *sbi = EXT4_SB(sb);
 782         struct ext4_super_block *es = sbi->s_es;
 783         int i, err;
 784
 785         ext4_unregister_li_request(sb);
 786         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 787
 788         flush_workqueue(sbi->rsv_conversion_wq);
 789         destroy_workqueue(sbi->rsv_conversion_wq);
 790
 791         if (sbi->s_journal) {
 792                 err = jbd2_journal_destroy(sbi->s_journal);
 793                 sbi->s_journal = NULL;
 794                 if (err < 0)
 795                         ext4_abort(sb, "Couldn't clean up the journal");
 796         }
 797
 798         ext4_unregister_sysfs(sb);
 799         ext4_es_unregister_shrinker(sbi);
 800         del_timer_sync(&sbi->s_err_report);
 801         ext4_release_system_zone(sb);
 802         ext4_mb_release(sb);
 803         ext4_ext_release(sb);
 804         ext4_xattr_put_super(sb);
 805
 806         if (!(sb->s_flags & MS_RDONLY)) {
 807                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 808                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 809         }
 810         if (!(sb->s_flags & MS_RDONLY))
 811                 ext4_commit_super(sb, 1);
 812
 813         for (i = 0; i < sbi->s_gdb_count; i++)
 814                 brelse(sbi->s_group_desc[i]);
 815         kvfree(sbi->s_group_desc);
 816         kvfree(sbi->s_flex_groups);
 817         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 818         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 819         percpu_counter_destroy(&sbi->s_dirs_counter);
 820         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 821         brelse(sbi->s_sbh);
 822 #ifdef CONFIG_QUOTA
 823         for (i = 0; i < EXT4_MAXQUOTAS; i++)
 824                 kfree(sbi->s_qf_names[i]);
 825 #endif
 826
 827         /* Debugging code just in case the in-memory inode orphan list
 828          * isn't empty.  The on-disk one can be non-empty if we've
 829          * detected an error and taken the fs readonly, but the
 830          * in-memory list had better be clean by this point. */
 831         if (!list_empty(&sbi->s_orphan))
 832                 dump_orphan_list(sb, sbi);
 833         J_ASSERT(list_empty(&sbi->s_orphan));
 834
 835         sync_blockdev(sb->s_bdev);
 836         invalidate_bdev(sb->s_bdev);
 837         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 838                 /*
 839                  * Invalidate the journal device's buffers.  We don't want them
 840                  * floating about in memory - the physical journal device may
 841                  * hotswapped, and it breaks the `ro-after' testing code.
 842                  */
 843                 sync_blockdev(sbi->journal_bdev);
 844                 invalidate_bdev(sbi->journal_bdev);
 845                 ext4_blkdev_remove(sbi);
 846         }
 847         if (sbi->s_mb_cache) {
 848                 ext4_xattr_destroy_cache(sbi->s_mb_cache);
 849                 sbi->s_mb_cache = NULL;
 850         }
 851         if (sbi->s_mmp_tsk)
 852                 kthread_stop(sbi->s_mmp_tsk);
 853         sb->s_fs_info = NULL;
 854         /*
 855          * Now that we are completely done shutting down the
 856          * superblock, we need to actually destroy the kobject.
 857          */
 858         kobject_put(&sbi->s_kobj);
 859         wait_for_completion(&sbi->s_kobj_unregister);
 860         if (sbi->s_chksum_driver)
 861                 crypto_free_shash(sbi->s_chksum_driver);
 862         kfree(sbi->s_blockgroup_lock);
 863         kfree(sbi);
 864 }
 865
 866 static struct kmem_cache *ext4_inode_cachep;
 867
 868 /*
 869  * Called inside transaction, so use GFP_NOFS
 870  */
 871 static struct inode *ext4_alloc_inode(struct super_block *sb)
 872 {
 873         struct ext4_inode_info *ei;
 874
 875         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 876         if (!ei)
 877                 return NULL;
 878
 879         ei->vfs_inode.i_version = 1;
 880         spin_lock_init(&ei->i_raw_lock);
 881         INIT_LIST_HEAD(&ei->i_prealloc_list);
 882         spin_lock_init(&ei->i_prealloc_lock);
 883         ext4_es_init_tree(&ei->i_es_tree);
 884         rwlock_init(&ei->i_es_lock);
 885         INIT_LIST_HEAD(&ei->i_es_list);
 886         ei->i_es_all_nr = 0;
 887         ei->i_es_shk_nr = 0;
 888         ei->i_es_shrink_lblk = 0;
 889         ei->i_reserved_data_blocks = 0;
 890         ei->i_reserved_meta_blocks = 0;
 891         ei->i_allocated_meta_blocks = 0;
 892         ei->i_da_metadata_calc_len = 0;
 893         ei->i_da_metadata_calc_last_lblock = 0;
 894         spin_lock_init(&(ei->i_block_reservation_lock));
 895 #ifdef CONFIG_QUOTA
 896         ei->i_reserved_quota = 0;
 897         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
 898 #endif
 899         ei->jinode = NULL;
 900         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
 901         spin_lock_init(&ei->i_completed_io_lock);
 902         ei->i_sync_tid = 0;
 903         ei->i_datasync_tid = 0;
 904         atomic_set(&ei->i_ioend_count, 0);
 905         atomic_set(&ei->i_unwritten, 0);
 906         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
 907 #ifdef CONFIG_EXT4_FS_ENCRYPTION
 908         ei->i_crypt_info = NULL;
 909 #endif
 910         return &ei->vfs_inode;
 911 }
 912
 913 static int ext4_drop_inode(struct inode *inode)
 914 {
 915         int drop = generic_drop_inode(inode);
 916
 917         trace_ext4_drop_inode(inode, drop);
 918         return drop;
 919 }
 920
 921 static void ext4_i_callback(struct rcu_head *head)
 922 {
 923         struct inode *inode = container_of(head, struct inode, i_rcu);
 924         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 925 }
 926
 927 static void ext4_destroy_inode(struct inode *inode)
 928 {
 929         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 930                 ext4_msg(inode->i_sb, KERN_ERR,
 931                          "Inode %lu (%p): orphan list check failed!",
 932                          inode->i_ino, EXT4_I(inode));
 933                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 934                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 935                                 true);
 936                 dump_stack();
 937         }
 938         call_rcu(&inode->i_rcu, ext4_i_callback);
 939 }
 940
 941 static void init_once(void *foo)
 942 {
 943         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 944
 945         INIT_LIST_HEAD(&ei->i_orphan);
 946         init_rwsem(&ei->xattr_sem);
 947         init_rwsem(&ei->i_data_sem);
 948         inode_init_once(&ei->vfs_inode);
 949 }
 950
 951 static int __init init_inodecache(void)
 952 {
 953         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 954                                              sizeof(struct ext4_inode_info),
 955                                              0, (SLAB_RECLAIM_ACCOUNT|
 956                                                 SLAB_MEM_SPREAD),
 957                                              init_once);
 958         if (ext4_inode_cachep == NULL)
 959                 return -ENOMEM;
 960         return 0;
 961 }
 962
 963 static void destroy_inodecache(void)
 964 {
 965         /*
 966          * Make sure all delayed rcu free inodes are flushed before we
 967          * destroy cache.
 968          */
 969         rcu_barrier();
 970         kmem_cache_destroy(ext4_inode_cachep);
 971 }
 972
 973 void ext4_clear_inode(struct inode *inode)
 974 {
 975         invalidate_inode_buffers(inode);
 976         clear_inode(inode);
 977         dquot_drop(inode);
 978         ext4_discard_preallocations(inode);
 979         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
 980         if (EXT4_I(inode)->jinode) {
 981                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
 982                                                EXT4_I(inode)->jinode);
 983                 jbd2_free_inode(EXT4_I(inode)->jinode);
 984                 EXT4_I(inode)->jinode = NULL;
 985         }
 986 #ifdef CONFIG_EXT4_FS_ENCRYPTION
 987         if (EXT4_I(inode)->i_crypt_info)
 988                 ext4_free_encryption_info(inode, EXT4_I(inode)->i_crypt_info);
 989 #endif
 990 }
 991
 992 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 993                                         u64 ino, u32 generation)
 994 {
 995         struct inode *inode;
 996
 997         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 998                 return ERR_PTR(-ESTALE);
 999         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1000                 return ERR_PTR(-ESTALE);
1001
1002         /* iget isn't really right if the inode is currently unallocated!!
1003          *
1004          * ext4_read_inode will return a bad_inode if the inode had been
1005          * deleted, so we should be safe.
1006          *
1007          * Currently we don't know the generation for parent directory, so
1008          * a generation of 0 means "accept any"
1009          */
1010         inode = ext4_iget_normal(sb, ino);
1011         if (IS_ERR(inode))
1012                 return ERR_CAST(inode);
1013         if (generation && inode->i_generation != generation) {
1014                 iput(inode);
1015                 return ERR_PTR(-ESTALE);
1016         }
1017
1018         return inode;
1019 }
1020
1021 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1022                                         int fh_len, int fh_type)
1023 {
1024         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1025                                     ext4_nfs_get_inode);
1026 }
1027
1028 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1029                                         int fh_len, int fh_type)
1030 {
1031         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1032                                     ext4_nfs_get_inode);
1033 }
1034
1035 /*
1036  * Try to release metadata pages (indirect blocks, directories) which are
1037  * mapped via the block device.  Since these pages could have journal heads
1038  * which would prevent try_to_free_buffers() from freeing them, we must use
1039  * jbd2 layer's try_to_free_buffers() function to release them.
1040  */
1041 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1042                                  gfp_t wait)
1043 {
1044         journal_t *journal = EXT4_SB(sb)->s_journal;
1045
1046         WARN_ON(PageChecked(page));
1047         if (!page_has_buffers(page))
1048                 return 0;
1049         if (journal)
1050                 return jbd2_journal_try_to_free_buffers(journal, page,
1051                                                         wait & ~__GFP_WAIT);
1052         return try_to_free_buffers(page);
1053 }
1054
1055 #ifdef CONFIG_QUOTA
1056 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1057 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1058
1059 static int ext4_write_dquot(struct dquot *dquot);
1060 static int ext4_acquire_dquot(struct dquot *dquot);
1061 static int ext4_release_dquot(struct dquot *dquot);
1062 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1063 static int ext4_write_info(struct super_block *sb, int type);
1064 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1065                          struct path *path);
1066 static int ext4_quota_off(struct super_block *sb, int type);
1067 static int ext4_quota_on_mount(struct super_block *sb, int type);
1068 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1069                                size_t len, loff_t off);
1070 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1071                                 const char *data, size_t len, loff_t off);
1072 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1073                              unsigned int flags);
1074 static int ext4_enable_quotas(struct super_block *sb);
1075
1076 static struct dquot **ext4_get_dquots(struct inode *inode)
1077 {
1078         return EXT4_I(inode)->i_dquot;
1079 }
1080
1081 static const struct dquot_operations ext4_quota_operations = {
1082         .get_reserved_space = ext4_get_reserved_space,
1083         .write_dquot    = ext4_write_dquot,
1084         .acquire_dquot  = ext4_acquire_dquot,
1085         .release_dquot  = ext4_release_dquot,
1086         .mark_dirty     = ext4_mark_dquot_dirty,
1087         .write_info     = ext4_write_info,
1088         .alloc_dquot    = dquot_alloc,
1089         .destroy_dquot  = dquot_destroy,
1090 };
1091
1092 static const struct quotactl_ops ext4_qctl_operations = {
1093         .quota_on       = ext4_quota_on,
1094         .quota_off      = ext4_quota_off,
1095         .quota_sync     = dquot_quota_sync,
1096         .get_state      = dquot_get_state,
1097         .set_info       = dquot_set_dqinfo,
1098         .get_dqblk      = dquot_get_dqblk,
1099         .set_dqblk      = dquot_set_dqblk
1100 };
1101 #endif
1102
1103 static const struct super_operations ext4_sops = {
1104         .alloc_inode    = ext4_alloc_inode,
1105         .destroy_inode  = ext4_destroy_inode,
1106         .write_inode    = ext4_write_inode,
1107         .dirty_inode    = ext4_dirty_inode,
1108         .drop_inode     = ext4_drop_inode,
1109         .evict_inode    = ext4_evict_inode,
1110         .put_super      = ext4_put_super,
1111         .sync_fs        = ext4_sync_fs,
1112         .freeze_fs      = ext4_freeze,
1113         .unfreeze_fs    = ext4_unfreeze,
1114         .statfs         = ext4_statfs,
1115         .remount_fs     = ext4_remount,
1116         .show_options   = ext4_show_options,
1117 #ifdef CONFIG_QUOTA
1118         .quota_read     = ext4_quota_read,
1119         .quota_write    = ext4_quota_write,
1120         .get_dquots     = ext4_get_dquots,
1121 #endif
1122         .bdev_try_to_free_page = bdev_try_to_free_page,
1123 };
1124
1125 static const struct export_operations ext4_export_ops = {
1126         .fh_to_dentry = ext4_fh_to_dentry,
1127         .fh_to_parent = ext4_fh_to_parent,
1128         .get_parent = ext4_get_parent,
1129 };
1130
1131 enum {
1132         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1133         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1134         Opt_nouid32, Opt_debug, Opt_removed,
1135         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1136         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1137         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1138         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1139         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1140         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1141         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1142         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1143         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1144         Opt_usrquota, Opt_grpquota, Opt_i_version, Opt_dax,
1145         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1146         Opt_lazytime, Opt_nolazytime,
1147         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1148         Opt_inode_readahead_blks, Opt_journal_ioprio,
1149         Opt_dioread_nolock, Opt_dioread_lock,
1150         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1151         Opt_max_dir_size_kb, Opt_nojournal_checksum,
1152 };
1153
1154 static const match_table_t tokens = {
1155         {Opt_bsd_df, "bsddf"},
1156         {Opt_minix_df, "minixdf"},
1157         {Opt_grpid, "grpid"},
1158         {Opt_grpid, "bsdgroups"},
1159         {Opt_nogrpid, "nogrpid"},
1160         {Opt_nogrpid, "sysvgroups"},
1161         {Opt_resgid, "resgid=%u"},
1162         {Opt_resuid, "resuid=%u"},
1163         {Opt_sb, "sb=%u"},
1164         {Opt_err_cont, "errors=continue"},
1165         {Opt_err_panic, "errors=panic"},
1166         {Opt_err_ro, "errors=remount-ro"},
1167         {Opt_nouid32, "nouid32"},
1168         {Opt_debug, "debug"},
1169         {Opt_removed, "oldalloc"},
1170         {Opt_removed, "orlov"},
1171         {Opt_user_xattr, "user_xattr"},
1172         {Opt_nouser_xattr, "nouser_xattr"},
1173         {Opt_acl, "acl"},
1174         {Opt_noacl, "noacl"},
1175         {Opt_noload, "norecovery"},
1176         {Opt_noload, "noload"},
1177         {Opt_removed, "nobh"},
1178         {Opt_removed, "bh"},
1179         {Opt_commit, "commit=%u"},
1180         {Opt_min_batch_time, "min_batch_time=%u"},
1181         {Opt_max_batch_time, "max_batch_time=%u"},
1182         {Opt_journal_dev, "journal_dev=%u"},
1183         {Opt_journal_path, "journal_path=%s"},
1184         {Opt_journal_checksum, "journal_checksum"},
1185         {Opt_nojournal_checksum, "nojournal_checksum"},
1186         {Opt_journal_async_commit, "journal_async_commit"},
1187         {Opt_abort, "abort"},
1188         {Opt_data_journal, "data=journal"},
1189         {Opt_data_ordered, "data=ordered"},
1190         {Opt_data_writeback, "data=writeback"},
1191         {Opt_data_err_abort, "data_err=abort"},
1192         {Opt_data_err_ignore, "data_err=ignore"},
1193         {Opt_offusrjquota, "usrjquota="},
1194         {Opt_usrjquota, "usrjquota=%s"},
1195         {Opt_offgrpjquota, "grpjquota="},
1196         {Opt_grpjquota, "grpjquota=%s"},
1197         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1198         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1199         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1200         {Opt_grpquota, "grpquota"},
1201         {Opt_noquota, "noquota"},
1202         {Opt_quota, "quota"},
1203         {Opt_usrquota, "usrquota"},
1204         {Opt_barrier, "barrier=%u"},
1205         {Opt_barrier, "barrier"},
1206         {Opt_nobarrier, "nobarrier"},
1207         {Opt_i_version, "i_version"},
1208         {Opt_dax, "dax"},
1209         {Opt_stripe, "stripe=%u"},
1210         {Opt_delalloc, "delalloc"},
1211         {Opt_lazytime, "lazytime"},
1212         {Opt_nolazytime, "nolazytime"},
1213         {Opt_nodelalloc, "nodelalloc"},
1214         {Opt_removed, "mblk_io_submit"},
1215         {Opt_removed, "nomblk_io_submit"},
1216         {Opt_block_validity, "block_validity"},
1217         {Opt_noblock_validity, "noblock_validity"},
1218         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1219         {Opt_journal_ioprio, "journal_ioprio=%u"},
1220         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1221         {Opt_auto_da_alloc, "auto_da_alloc"},
1222         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1223         {Opt_dioread_nolock, "dioread_nolock"},
1224         {Opt_dioread_lock, "dioread_lock"},
1225         {Opt_discard, "discard"},
1226         {Opt_nodiscard, "nodiscard"},
1227         {Opt_init_itable, "init_itable=%u"},
1228         {Opt_init_itable, "init_itable"},
1229         {Opt_noinit_itable, "noinit_itable"},
1230         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1231         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1232         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1233         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1234         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1235         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1236         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1237         {Opt_err, NULL},
1238 };
1239
1240 static ext4_fsblk_t get_sb_block(void **data)
1241 {
1242         ext4_fsblk_t    sb_block;
1243         char            *options = (char *) *data;
1244
1245         if (!options || strncmp(options, "sb=", 3) != 0)
1246                 return 1;       /* Default location */
1247
1248         options += 3;
1249         /* TODO: use simple_strtoll with >32bit ext4 */
1250         sb_block = simple_strtoul(options, &options, 0);
1251         if (*options && *options != ',') {
1252                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1253                        (char *) *data);
1254                 return 1;
1255         }
1256         if (*options == ',')
1257                 options++;
1258         *data = (void *) options;
1259
1260         return sb_block;
1261 }
1262
1263 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1264 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1265         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1266
1267 #ifdef CONFIG_QUOTA
1268 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1269 {
1270         struct ext4_sb_info *sbi = EXT4_SB(sb);
1271         char *qname;
1272         int ret = -1;
1273
1274         if (sb_any_quota_loaded(sb) &&
1275                 !sbi->s_qf_names[qtype]) {
1276                 ext4_msg(sb, KERN_ERR,
1277                         "Cannot change journaled "
1278                         "quota options when quota turned on");
1279                 return -1;
1280         }
1281         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1282                 ext4_msg(sb, KERN_ERR, "Cannot set journaled quota options "
1283                          "when QUOTA feature is enabled");
1284                 return -1;
1285         }
1286         qname = match_strdup(args);
1287         if (!qname) {
1288                 ext4_msg(sb, KERN_ERR,
1289                         "Not enough memory for storing quotafile name");
1290                 return -1;
1291         }
1292         if (sbi->s_qf_names[qtype]) {
1293                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1294                         ret = 1;
1295                 else
1296                         ext4_msg(sb, KERN_ERR,
1297                                  "%s quota file already specified",
1298                                  QTYPE2NAME(qtype));
1299                 goto errout;
1300         }
1301         if (strchr(qname, '/')) {
1302                 ext4_msg(sb, KERN_ERR,
1303                         "quotafile must be on filesystem root");
1304                 goto errout;
1305         }
1306         sbi->s_qf_names[qtype] = qname;
1307         set_opt(sb, QUOTA);
1308         return 1;
1309 errout:
1310         kfree(qname);
1311         return ret;
1312 }
1313
1314 static int clear_qf_name(struct super_block *sb, int qtype)
1315 {
1316
1317         struct ext4_sb_info *sbi = EXT4_SB(sb);
1318
1319         if (sb_any_quota_loaded(sb) &&
1320                 sbi->s_qf_names[qtype]) {
1321                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1322                         " when quota turned on");
1323                 return -1;
1324         }
1325         kfree(sbi->s_qf_names[qtype]);
1326         sbi->s_qf_names[qtype] = NULL;
1327         return 1;
1328 }
1329 #endif
1330
1331 #define MOPT_SET        0x0001
1332 #define MOPT_CLEAR      0x0002
1333 #define MOPT_NOSUPPORT  0x0004
1334 #define MOPT_EXPLICIT   0x0008
1335 #define MOPT_CLEAR_ERR  0x0010
1336 #define MOPT_GTE0       0x0020
1337 #ifdef CONFIG_QUOTA
1338 #define MOPT_Q          0
1339 #define MOPT_QFMT       0x0040
1340 #else
1341 #define MOPT_Q          MOPT_NOSUPPORT
1342 #define MOPT_QFMT       MOPT_NOSUPPORT
1343 #endif
1344 #define MOPT_DATAJ      0x0080
1345 #define MOPT_NO_EXT2    0x0100
1346 #define MOPT_NO_EXT3    0x0200
1347 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1348 #define MOPT_STRING     0x0400
1349
1350 static const struct mount_opts {
1351         int     token;
1352         int     mount_opt;
1353         int     flags;
1354 } ext4_mount_opts[] = {
1355         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1356         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1357         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1358         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1359         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1360         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1361         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1362          MOPT_EXT4_ONLY | MOPT_SET},
1363         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1364          MOPT_EXT4_ONLY | MOPT_CLEAR},
1365         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1366         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1367         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1368          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1369         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1370          MOPT_EXT4_ONLY | MOPT_CLEAR},
1371         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1372          MOPT_EXT4_ONLY | MOPT_CLEAR},
1373         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1374          MOPT_EXT4_ONLY | MOPT_SET},
1375         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1376                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1377          MOPT_EXT4_ONLY | MOPT_SET},
1378         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1379         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1380         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1381         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1382         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1383          MOPT_NO_EXT2 | MOPT_SET},
1384         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1385          MOPT_NO_EXT2 | MOPT_CLEAR},
1386         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1387         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1388         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1389         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1390         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1391         {Opt_commit, 0, MOPT_GTE0},
1392         {Opt_max_batch_time, 0, MOPT_GTE0},
1393         {Opt_min_batch_time, 0, MOPT_GTE0},
1394         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1395         {Opt_init_itable, 0, MOPT_GTE0},
1396         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1397         {Opt_stripe, 0, MOPT_GTE0},
1398         {Opt_resuid, 0, MOPT_GTE0},
1399         {Opt_resgid, 0, MOPT_GTE0},
1400         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1401         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1402         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1403         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1404         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1405         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1406          MOPT_NO_EXT2 | MOPT_DATAJ},
1407         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1408         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1409 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1410         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1411         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1412 #else
1413         {Opt_acl, 0, MOPT_NOSUPPORT},
1414         {Opt_noacl, 0, MOPT_NOSUPPORT},
1415 #endif
1416         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1417         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1418         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1419         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1420                                                         MOPT_SET | MOPT_Q},
1421         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1422                                                         MOPT_SET | MOPT_Q},
1423         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1424                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1425         {Opt_usrjquota, 0, MOPT_Q},
1426         {Opt_grpjquota, 0, MOPT_Q},
1427         {Opt_offusrjquota, 0, MOPT_Q},
1428         {Opt_offgrpjquota, 0, MOPT_Q},
1429         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1430         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1431         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1432         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1433         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1434         {Opt_err, 0, 0}
1435 };
1436
1437 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1438                             substring_t *args, unsigned long *journal_devnum,
1439                             unsigned int *journal_ioprio, int is_remount)
1440 {
1441         struct ext4_sb_info *sbi = EXT4_SB(sb);
1442         const struct mount_opts *m;
1443         kuid_t uid;
1444         kgid_t gid;
1445         int arg = 0;
1446
1447 #ifdef CONFIG_QUOTA
1448         if (token == Opt_usrjquota)
1449                 return set_qf_name(sb, USRQUOTA, &args[0]);
1450         else if (token == Opt_grpjquota)
1451                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1452         else if (token == Opt_offusrjquota)
1453                 return clear_qf_name(sb, USRQUOTA);
1454         else if (token == Opt_offgrpjquota)
1455                 return clear_qf_name(sb, GRPQUOTA);
1456 #endif
1457         switch (token) {
1458         case Opt_noacl:
1459         case Opt_nouser_xattr:
1460                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1461                 break;
1462         case Opt_sb:
1463                 return 1;       /* handled by get_sb_block() */
1464         case Opt_removed:
1465                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1466                 return 1;
1467         case Opt_abort:
1468                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1469                 return 1;
1470         case Opt_i_version:
1471                 sb->s_flags |= MS_I_VERSION;
1472                 return 1;
1473         case Opt_lazytime:
1474                 sb->s_flags |= MS_LAZYTIME;
1475                 return 1;
1476         case Opt_nolazytime:
1477                 sb->s_flags &= ~MS_LAZYTIME;
1478                 return 1;
1479         }
1480
1481         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1482                 if (token == m->token)
1483                         break;
1484
1485         if (m->token == Opt_err) {
1486                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1487                          "or missing value", opt);
1488                 return -1;
1489         }
1490
1491         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1492                 ext4_msg(sb, KERN_ERR,
1493                          "Mount option \"%s\" incompatible with ext2", opt);
1494                 return -1;
1495         }
1496         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1497                 ext4_msg(sb, KERN_ERR,
1498                          "Mount option \"%s\" incompatible with ext3", opt);
1499                 return -1;
1500         }
1501
1502         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1503                 return -1;
1504         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1505                 return -1;
1506         if (m->flags & MOPT_EXPLICIT)
1507                 set_opt2(sb, EXPLICIT_DELALLOC);
1508         if (m->flags & MOPT_CLEAR_ERR)
1509                 clear_opt(sb, ERRORS_MASK);
1510         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1511                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1512                          "options when quota turned on");
1513                 return -1;
1514         }
1515
1516         if (m->flags & MOPT_NOSUPPORT) {
1517                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1518         } else if (token == Opt_commit) {
1519                 if (arg == 0)
1520                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1521                 sbi->s_commit_interval = HZ * arg;
1522         } else if (token == Opt_max_batch_time) {
1523                 sbi->s_max_batch_time = arg;
1524         } else if (token == Opt_min_batch_time) {
1525                 sbi->s_min_batch_time = arg;
1526         } else if (token == Opt_inode_readahead_blks) {
1527                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1528                         ext4_msg(sb, KERN_ERR,
1529                                  "EXT4-fs: inode_readahead_blks must be "
1530                                  "0 or a power of 2 smaller than 2^31");
1531                         return -1;
1532                 }
1533                 sbi->s_inode_readahead_blks = arg;
1534         } else if (token == Opt_init_itable) {
1535                 set_opt(sb, INIT_INODE_TABLE);
1536                 if (!args->from)
1537                         arg = EXT4_DEF_LI_WAIT_MULT;
1538                 sbi->s_li_wait_mult = arg;
1539         } else if (token == Opt_max_dir_size_kb) {
1540                 sbi->s_max_dir_size_kb = arg;
1541         } else if (token == Opt_stripe) {
1542                 sbi->s_stripe = arg;
1543         } else if (token == Opt_resuid) {
1544                 uid = make_kuid(current_user_ns(), arg);
1545                 if (!uid_valid(uid)) {
1546                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1547                         return -1;
1548                 }
1549                 sbi->s_resuid = uid;
1550         } else if (token == Opt_resgid) {
1551                 gid = make_kgid(current_user_ns(), arg);
1552                 if (!gid_valid(gid)) {
1553                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1554                         return -1;
1555                 }
1556                 sbi->s_resgid = gid;
1557         } else if (token == Opt_journal_dev) {
1558                 if (is_remount) {
1559                         ext4_msg(sb, KERN_ERR,
1560                                  "Cannot specify journal on remount");
1561                         return -1;
1562                 }
1563                 *journal_devnum = arg;
1564         } else if (token == Opt_journal_path) {
1565                 char *journal_path;
1566                 struct inode *journal_inode;
1567                 struct path path;
1568                 int error;
1569
1570                 if (is_remount) {
1571                         ext4_msg(sb, KERN_ERR,
1572                                  "Cannot specify journal on remount");
1573                         return -1;
1574                 }
1575                 journal_path = match_strdup(&args[0]);
1576                 if (!journal_path) {
1577                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1578                                 "journal device string");
1579                         return -1;
1580                 }
1581
1582                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1583                 if (error) {
1584                         ext4_msg(sb, KERN_ERR, "error: could not find "
1585                                 "journal device path: error %d", error);
1586                         kfree(journal_path);
1587                         return -1;
1588                 }
1589
1590                 journal_inode = d_inode(path.dentry);
1591                 if (!S_ISBLK(journal_inode->i_mode)) {
1592                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1593                                 "is not a block device", journal_path);
1594                         path_put(&path);
1595                         kfree(journal_path);
1596                         return -1;
1597                 }
1598
1599                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1600                 path_put(&path);
1601                 kfree(journal_path);
1602         } else if (token == Opt_journal_ioprio) {
1603                 if (arg > 7) {
1604                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1605                                  " (must be 0-7)");
1606                         return -1;
1607                 }
1608                 *journal_ioprio =
1609                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1610         } else if (token == Opt_test_dummy_encryption) {
1611 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1612                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1613                 ext4_msg(sb, KERN_WARNING,
1614                          "Test dummy encryption mode enabled");
1615 #else
1616                 ext4_msg(sb, KERN_WARNING,
1617                          "Test dummy encryption mount option ignored");
1618 #endif
1619         } else if (m->flags & MOPT_DATAJ) {
1620                 if (is_remount) {
1621                         if (!sbi->s_journal)
1622                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1623                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1624                                 ext4_msg(sb, KERN_ERR,
1625                                          "Cannot change data mode on remount");
1626                                 return -1;
1627                         }
1628                 } else {
1629                         clear_opt(sb, DATA_FLAGS);
1630                         sbi->s_mount_opt |= m->mount_opt;
1631                 }
1632 #ifdef CONFIG_QUOTA
1633         } else if (m->flags & MOPT_QFMT) {
1634                 if (sb_any_quota_loaded(sb) &&
1635                     sbi->s_jquota_fmt != m->mount_opt) {
1636                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1637                                  "quota options when quota turned on");
1638                         return -1;
1639                 }
1640                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
1641                                                EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1642                         ext4_msg(sb, KERN_ERR,
1643                                  "Cannot set journaled quota options "
1644                                  "when QUOTA feature is enabled");
1645                         return -1;
1646                 }
1647                 sbi->s_jquota_fmt = m->mount_opt;
1648 #endif
1649 #ifndef CONFIG_FS_DAX
1650         } else if (token == Opt_dax) {
1651                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1652                 return -1;
1653 #endif
1654         } else {
1655                 if (!args->from)
1656                         arg = 1;
1657                 if (m->flags & MOPT_CLEAR)
1658                         arg = !arg;
1659                 else if (unlikely(!(m->flags & MOPT_SET))) {
1660                         ext4_msg(sb, KERN_WARNING,
1661                                  "buggy handling of option %s", opt);
1662                         WARN_ON(1);
1663                         return -1;
1664                 }
1665                 if (arg != 0)
1666                         sbi->s_mount_opt |= m->mount_opt;
1667                 else
1668                         sbi->s_mount_opt &= ~m->mount_opt;
1669         }
1670         return 1;
1671 }
1672
1673 static int parse_options(char *options, struct super_block *sb,
1674                          unsigned long *journal_devnum,
1675                          unsigned int *journal_ioprio,
1676                          int is_remount)
1677 {
1678         struct ext4_sb_info *sbi = EXT4_SB(sb);
1679         char *p;
1680         substring_t args[MAX_OPT_ARGS];
1681         int token;
1682
1683         if (!options)
1684                 return 1;
1685
1686         while ((p = strsep(&options, ",")) != NULL) {
1687                 if (!*p)
1688                         continue;
1689                 /*
1690                  * Initialize args struct so we know whether arg was
1691                  * found; some options take optional arguments.
1692                  */
1693                 args[0].to = args[0].from = NULL;
1694                 token = match_token(p, tokens, args);
1695                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1696                                      journal_ioprio, is_remount) < 0)
1697                         return 0;
1698         }
1699 #ifdef CONFIG_QUOTA
1700         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
1701             (test_opt(sb, USRQUOTA) || test_opt(sb, GRPQUOTA))) {
1702                 ext4_msg(sb, KERN_ERR, "Cannot set quota options when QUOTA "
1703                          "feature is enabled");
1704                 return 0;
1705         }
1706         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1707                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1708                         clear_opt(sb, USRQUOTA);
1709
1710                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1711                         clear_opt(sb, GRPQUOTA);
1712
1713                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1714                         ext4_msg(sb, KERN_ERR, "old and new quota "
1715                                         "format mixing");
1716                         return 0;
1717                 }
1718
1719                 if (!sbi->s_jquota_fmt) {
1720                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1721                                         "not specified");
1722                         return 0;
1723                 }
1724         }
1725 #endif
1726         if (test_opt(sb, DIOREAD_NOLOCK)) {
1727                 int blocksize =
1728                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1729
1730                 if (blocksize < PAGE_CACHE_SIZE) {
1731                         ext4_msg(sb, KERN_ERR, "can't mount with "
1732                                  "dioread_nolock if block size != PAGE_SIZE");
1733                         return 0;
1734                 }
1735         }
1736         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
1737             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
1738                 ext4_msg(sb, KERN_ERR, "can't mount with journal_async_commit "
1739                          "in data=ordered mode");
1740                 return 0;
1741         }
1742         return 1;
1743 }
1744
1745 static inline void ext4_show_quota_options(struct seq_file *seq,
1746                                            struct super_block *sb)
1747 {
1748 #if defined(CONFIG_QUOTA)
1749         struct ext4_sb_info *sbi = EXT4_SB(sb);
1750
1751         if (sbi->s_jquota_fmt) {
1752                 char *fmtname = "";
1753
1754                 switch (sbi->s_jquota_fmt) {
1755                 case QFMT_VFS_OLD:
1756                         fmtname = "vfsold";
1757                         break;
1758                 case QFMT_VFS_V0:
1759                         fmtname = "vfsv0";
1760                         break;
1761                 case QFMT_VFS_V1:
1762                         fmtname = "vfsv1";
1763                         break;
1764                 }
1765                 seq_printf(seq, ",jqfmt=%s", fmtname);
1766         }
1767
1768         if (sbi->s_qf_names[USRQUOTA])
1769                 seq_show_option(seq, "usrjquota", sbi->s_qf_names[USRQUOTA]);
1770
1771         if (sbi->s_qf_names[GRPQUOTA])
1772                 seq_show_option(seq, "grpjquota", sbi->s_qf_names[GRPQUOTA]);
1773 #endif
1774 }
1775
1776 static const char *token2str(int token)
1777 {
1778         const struct match_token *t;
1779
1780         for (t = tokens; t->token != Opt_err; t++)
1781                 if (t->token == token && !strchr(t->pattern, '='))
1782                         break;
1783         return t->pattern;
1784 }
1785
1786 /*
1787  * Show an option if
1788  *  - it's set to a non-default value OR
1789  *  - if the per-sb default is different from the global default
1790  */
1791 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1792                               int nodefs)
1793 {
1794         struct ext4_sb_info *sbi = EXT4_SB(sb);
1795         struct ext4_super_block *es = sbi->s_es;
1796         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1797         const struct mount_opts *m;
1798         char sep = nodefs ? '\n' : ',';
1799
1800 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1801 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1802
1803         if (sbi->s_sb_block != 1)
1804                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1805
1806         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1807                 int want_set = m->flags & MOPT_SET;
1808                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1809                     (m->flags & MOPT_CLEAR_ERR))
1810                         continue;
1811                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1812                         continue; /* skip if same as the default */
1813                 if ((want_set &&
1814                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1815                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1816                         continue; /* select Opt_noFoo vs Opt_Foo */
1817                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1818         }
1819
1820         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1821             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1822                 SEQ_OPTS_PRINT("resuid=%u",
1823                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1824         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1825             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1826                 SEQ_OPTS_PRINT("resgid=%u",
1827                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1828         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1829         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1830                 SEQ_OPTS_PUTS("errors=remount-ro");
1831         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1832                 SEQ_OPTS_PUTS("errors=continue");
1833         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1834                 SEQ_OPTS_PUTS("errors=panic");
1835         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1836                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1837         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1838                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1839         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1840                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1841         if (sb->s_flags & MS_I_VERSION)
1842                 SEQ_OPTS_PUTS("i_version");
1843         if (nodefs || sbi->s_stripe)
1844                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1845         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1846                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1847                         SEQ_OPTS_PUTS("data=journal");
1848                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1849                         SEQ_OPTS_PUTS("data=ordered");
1850                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1851                         SEQ_OPTS_PUTS("data=writeback");
1852         }
1853         if (nodefs ||
1854             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1855                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1856                                sbi->s_inode_readahead_blks);
1857
1858         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1859                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1860                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1861         if (nodefs || sbi->s_max_dir_size_kb)
1862                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
1863
1864         ext4_show_quota_options(seq, sb);
1865         return 0;
1866 }
1867
1868 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1869 {
1870         return _ext4_show_options(seq, root->d_sb, 0);
1871 }
1872
1873 int ext4_seq_options_show(struct seq_file *seq, void *offset)
1874 {
1875         struct super_block *sb = seq->private;
1876         int rc;
1877
1878         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1879         rc = _ext4_show_options(seq, sb, 1);
1880         seq_puts(seq, "\n");
1881         return rc;
1882 }
1883
1884 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1885                             int read_only)
1886 {
1887         struct ext4_sb_info *sbi = EXT4_SB(sb);
1888         int res = 0;
1889
1890         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1891                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1892                          "forcing read-only mode");
1893                 res = MS_RDONLY;
1894         }
1895         if (read_only)
1896                 goto done;
1897         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1898                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1899                          "running e2fsck is recommended");
1900         else if (sbi->s_mount_state & EXT4_ERROR_FS)
1901                 ext4_msg(sb, KERN_WARNING,
1902                          "warning: mounting fs with errors, "
1903                          "running e2fsck is recommended");
1904         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1905                  le16_to_cpu(es->s_mnt_count) >=
1906                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1907                 ext4_msg(sb, KERN_WARNING,
1908                          "warning: maximal mount count reached, "
1909                          "running e2fsck is recommended");
1910         else if (le32_to_cpu(es->s_checkinterval) &&
1911                 (le32_to_cpu(es->s_lastcheck) +
1912                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1913                 ext4_msg(sb, KERN_WARNING,
1914                          "warning: checktime reached, "
1915                          "running e2fsck is recommended");
1916         if (!sbi->s_journal)
1917                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1918         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1919                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1920         le16_add_cpu(&es->s_mnt_count, 1);
1921         es->s_mtime = cpu_to_le32(get_seconds());
1922         ext4_update_dynamic_rev(sb);
1923         if (sbi->s_journal)
1924                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1925
1926         ext4_commit_super(sb, 1);
1927 done:
1928         if (test_opt(sb, DEBUG))
1929                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1930                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1931                         sb->s_blocksize,
1932                         sbi->s_groups_count,
1933                         EXT4_BLOCKS_PER_GROUP(sb),
1934                         EXT4_INODES_PER_GROUP(sb),
1935                         sbi->s_mount_opt, sbi->s_mount_opt2);
1936
1937         cleancache_init_fs(sb);
1938         return res;
1939 }
1940
1941 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
1942 {
1943         struct ext4_sb_info *sbi = EXT4_SB(sb);
1944         struct flex_groups *new_groups;
1945         int size;
1946
1947         if (!sbi->s_log_groups_per_flex)
1948                 return 0;
1949
1950         size = ext4_flex_group(sbi, ngroup - 1) + 1;
1951         if (size <= sbi->s_flex_groups_allocated)
1952                 return 0;
1953
1954         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
1955         new_groups = ext4_kvzalloc(size, GFP_KERNEL);
1956         if (!new_groups) {
1957                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
1958                          size / (int) sizeof(struct flex_groups));
1959                 return -ENOMEM;
1960         }
1961
1962         if (sbi->s_flex_groups) {
1963                 memcpy(new_groups, sbi->s_flex_groups,
1964                        (sbi->s_flex_groups_allocated *
1965                         sizeof(struct flex_groups)));
1966                 kvfree(sbi->s_flex_groups);
1967         }
1968         sbi->s_flex_groups = new_groups;
1969         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
1970         return 0;
1971 }
1972
1973 static int ext4_fill_flex_info(struct super_block *sb)
1974 {
1975         struct ext4_sb_info *sbi = EXT4_SB(sb);
1976         struct ext4_group_desc *gdp = NULL;
1977         ext4_group_t flex_group;
1978         int i, err;
1979
1980         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1981         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1982                 sbi->s_log_groups_per_flex = 0;
1983                 return 1;
1984         }
1985
1986         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
1987         if (err)
1988                 goto failed;
1989
1990         for (i = 0; i < sbi->s_groups_count; i++) {
1991                 gdp = ext4_get_group_desc(sb, i, NULL);
1992
1993                 flex_group = ext4_flex_group(sbi, i);
1994                 atomic_add(ext4_free_inodes_count(sb, gdp),
1995                            &sbi->s_flex_groups[flex_group].free_inodes);
1996                 atomic64_add(ext4_free_group_clusters(sb, gdp),
1997                              &sbi->s_flex_groups[flex_group].free_clusters);
1998                 atomic_add(ext4_used_dirs_count(sb, gdp),
1999                            &sbi->s_flex_groups[flex_group].used_dirs);
2000         }
2001
2002         return 1;
2003 failed:
2004         return 0;
2005 }
2006
2007 static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
2008                                    struct ext4_group_desc *gdp)
2009 {
2010         int offset;
2011         __u16 crc = 0;
2012         __le32 le_group = cpu_to_le32(block_group);
2013
2014         if (ext4_has_metadata_csum(sbi->s_sb)) {
2015                 /* Use new metadata_csum algorithm */
2016                 __le16 save_csum;
2017                 __u32 csum32;
2018
2019                 save_csum = gdp->bg_checksum;
2020                 gdp->bg_checksum = 0;
2021                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2022                                      sizeof(le_group));
2023                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
2024                                      sbi->s_desc_size);
2025                 gdp->bg_checksum = save_csum;
2026
2027                 crc = csum32 & 0xFFFF;
2028                 goto out;
2029         }
2030
2031         /* old crc16 code */
2032         if (!(sbi->s_es->s_feature_ro_compat &
2033               cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)))
2034                 return 0;
2035
2036         offset = offsetof(struct ext4_group_desc, bg_checksum);
2037
2038         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2039         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2040         crc = crc16(crc, (__u8 *)gdp, offset);
2041         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2042         /* for checksum of struct ext4_group_desc do the rest...*/
2043         if ((sbi->s_es->s_feature_incompat &
2044              cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2045             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2046                 crc = crc16(crc, (__u8 *)gdp + offset,
2047                             le16_to_cpu(sbi->s_es->s_desc_size) -
2048                                 offset);
2049
2050 out:
2051         return cpu_to_le16(crc);
2052 }
2053
2054 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2055                                 struct ext4_group_desc *gdp)
2056 {
2057         if (ext4_has_group_desc_csum(sb) &&
2058             (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
2059                                                       block_group, gdp)))
2060                 return 0;
2061
2062         return 1;
2063 }
2064
2065 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2066                               struct ext4_group_desc *gdp)
2067 {
2068         if (!ext4_has_group_desc_csum(sb))
2069                 return;
2070         gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
2071 }
2072
2073 /* Called at mount-time, super-block is locked */
2074 static int ext4_check_descriptors(struct super_block *sb,
2075                                   ext4_group_t *first_not_zeroed)
2076 {
2077         struct ext4_sb_info *sbi = EXT4_SB(sb);
2078         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2079         ext4_fsblk_t last_block;
2080         ext4_fsblk_t block_bitmap;
2081         ext4_fsblk_t inode_bitmap;
2082         ext4_fsblk_t inode_table;
2083         int flexbg_flag = 0;
2084         ext4_group_t i, grp = sbi->s_groups_count;
2085
2086         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2087                 flexbg_flag = 1;
2088
2089         ext4_debug("Checking group descriptors");
2090
2091         for (i = 0; i < sbi->s_groups_count; i++) {
2092                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2093
2094                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2095                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2096                 else
2097                         last_block = first_block +
2098                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2099
2100                 if ((grp == sbi->s_groups_count) &&
2101                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2102                         grp = i;
2103
2104                 block_bitmap = ext4_block_bitmap(sb, gdp);
2105                 if (block_bitmap < first_block || block_bitmap > last_block) {
2106                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2107                                "Block bitmap for group %u not in group "
2108                                "(block %llu)!", i, block_bitmap);
2109                         return 0;
2110                 }
2111                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2112                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2113                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2114                                "Inode bitmap for group %u not in group "
2115                                "(block %llu)!", i, inode_bitmap);
2116                         return 0;
2117                 }
2118                 inode_table = ext4_inode_table(sb, gdp);
2119                 if (inode_table < first_block ||
2120                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2121                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2122                                "Inode table for group %u not in group "
2123                                "(block %llu)!", i, inode_table);
2124                         return 0;
2125                 }
2126                 ext4_lock_group(sb, i);
2127                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2128                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2129                                  "Checksum for group %u failed (%u!=%u)",
2130                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2131                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2132                         if (!(sb->s_flags & MS_RDONLY)) {
2133                                 ext4_unlock_group(sb, i);
2134                                 return 0;
2135                         }
2136                 }
2137                 ext4_unlock_group(sb, i);
2138                 if (!flexbg_flag)
2139                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2140         }
2141         if (NULL != first_not_zeroed)
2142                 *first_not_zeroed = grp;
2143         return 1;
2144 }
2145
2146 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2147  * the superblock) which were deleted from all directories, but held open by
2148  * a process at the time of a crash.  We walk the list and try to delete these
2149  * inodes at recovery time (only with a read-write filesystem).
2150  *
2151  * In order to keep the orphan inode chain consistent during traversal (in
2152  * case of crash during recovery), we link each inode into the superblock
2153  * orphan list_head and handle it the same way as an inode deletion during
2154  * normal operation (which journals the operations for us).
2155  *
2156  * We only do an iget() and an iput() on each inode, which is very safe if we
2157  * accidentally point at an in-use or already deleted inode.  The worst that
2158  * can happen in this case is that we get a "bit already cleared" message from
2159  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2160  * e2fsck was run on this filesystem, and it must have already done the orphan
2161  * inode cleanup for us, so we can safely abort without any further action.
2162  */
2163 static void ext4_orphan_cleanup(struct super_block *sb,
2164                                 struct ext4_super_block *es)
2165 {
2166         unsigned int s_flags = sb->s_flags;
2167         int nr_orphans = 0, nr_truncates = 0;
2168 #ifdef CONFIG_QUOTA
2169         int i;
2170 #endif
2171         if (!es->s_last_orphan) {
2172                 jbd_debug(4, "no orphan inodes to clean up\n");
2173                 return;
2174         }
2175
2176         if (bdev_read_only(sb->s_bdev)) {
2177                 ext4_msg(sb, KERN_ERR, "write access "
2178                         "unavailable, skipping orphan cleanup");
2179                 return;
2180         }
2181
2182         /* Check if feature set would not allow a r/w mount */
2183         if (!ext4_feature_set_ok(sb, 0)) {
2184                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2185                          "unknown ROCOMPAT features");
2186                 return;
2187         }
2188
2189         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2190                 /* don't clear list on RO mount w/ errors */
2191                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2192                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2193                                   "clearing orphan list.\n");
2194                         es->s_last_orphan = 0;
2195                 }
2196                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2197                 return;
2198         }
2199
2200         if (s_flags & MS_RDONLY) {
2201                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2202                 sb->s_flags &= ~MS_RDONLY;
2203         }
2204 #ifdef CONFIG_QUOTA
2205         /* Needed for iput() to work correctly and not trash data */
2206         sb->s_flags |= MS_ACTIVE;
2207         /* Turn on quotas so that they are updated correctly */
2208         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2209                 if (EXT4_SB(sb)->s_qf_names[i]) {
2210                         int ret = ext4_quota_on_mount(sb, i);
2211                         if (ret < 0)
2212                                 ext4_msg(sb, KERN_ERR,
2213                                         "Cannot turn on journaled "
2214                                         "quota: error %d", ret);
2215                 }
2216         }
2217 #endif
2218
2219         while (es->s_last_orphan) {
2220                 struct inode *inode;
2221
2222                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2223                 if (IS_ERR(inode)) {
2224                         es->s_last_orphan = 0;
2225                         break;
2226                 }
2227
2228                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2229                 dquot_initialize(inode);
2230                 if (inode->i_nlink) {
2231                         if (test_opt(sb, DEBUG))
2232                                 ext4_msg(sb, KERN_DEBUG,
2233                                         "%s: truncating inode %lu to %lld bytes",
2234                                         __func__, inode->i_ino, inode->i_size);
2235                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2236                                   inode->i_ino, inode->i_size);
2237                         mutex_lock(&inode->i_mutex);
2238                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2239                         ext4_truncate(inode);
2240                         mutex_unlock(&inode->i_mutex);
2241                         nr_truncates++;
2242                 } else {
2243                         if (test_opt(sb, DEBUG))
2244                                 ext4_msg(sb, KERN_DEBUG,
2245                                         "%s: deleting unreferenced inode %lu",
2246                                         __func__, inode->i_ino);
2247                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2248                                   inode->i_ino);
2249                         nr_orphans++;
2250                 }
2251                 iput(inode);  /* The delete magic happens here! */
2252         }
2253
2254 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2255
2256         if (nr_orphans)
2257                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2258                        PLURAL(nr_orphans));
2259         if (nr_truncates)
2260                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2261                        PLURAL(nr_truncates));
2262 #ifdef CONFIG_QUOTA
2263         /* Turn quotas off */
2264         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2265                 if (sb_dqopt(sb)->files[i])
2266                         dquot_quota_off(sb, i);
2267         }
2268 #endif
2269         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2270 }
2271
2272 /*
2273  * Maximal extent format file size.
2274  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2275  * extent format containers, within a sector_t, and within i_blocks
2276  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2277  * so that won't be a limiting factor.
2278  *
2279  * However there is other limiting factor. We do store extents in the form
2280  * of starting block and length, hence the resulting length of the extent
2281  * covering maximum file size must fit into on-disk format containers as
2282  * well. Given that length is always by 1 unit bigger than max unit (because
2283  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2284  *
2285  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2286  */
2287 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2288 {
2289         loff_t res;
2290         loff_t upper_limit = MAX_LFS_FILESIZE;
2291
2292         /* small i_blocks in vfs inode? */
2293         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2294                 /*
2295                  * CONFIG_LBDAF is not enabled implies the inode
2296                  * i_block represent total blocks in 512 bytes
2297                  * 32 == size of vfs inode i_blocks * 8
2298                  */
2299                 upper_limit = (1LL << 32) - 1;
2300
2301                 /* total blocks in file system block size */
2302                 upper_limit >>= (blkbits - 9);
2303                 upper_limit <<= blkbits;
2304         }
2305
2306         /*
2307          * 32-bit extent-start container, ee_block. We lower the maxbytes
2308          * by one fs block, so ee_len can cover the extent of maximum file
2309          * size
2310          */
2311         res = (1LL << 32) - 1;
2312         res <<= blkbits;
2313
2314         /* Sanity check against vm- & vfs- imposed limits */
2315         if (res > upper_limit)
2316                 res = upper_limit;
2317
2318         return res;
2319 }
2320
2321 /*
2322  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2323  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2324  * We need to be 1 filesystem block less than the 2^48 sector limit.
2325  */
2326 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2327 {
2328         loff_t res = EXT4_NDIR_BLOCKS;
2329         int meta_blocks;
2330         loff_t upper_limit;
2331         /* This is calculated to be the largest file size for a dense, block
2332          * mapped file such that the file's total number of 512-byte sectors,
2333          * including data and all indirect blocks, does not exceed (2^48 - 1).
2334          *
2335          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2336          * number of 512-byte sectors of the file.
2337          */
2338
2339         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2340                 /*
2341                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2342                  * the inode i_block field represents total file blocks in
2343                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2344                  */
2345                 upper_limit = (1LL << 32) - 1;
2346
2347                 /* total blocks in file system block size */
2348                 upper_limit >>= (bits - 9);
2349
2350         } else {
2351                 /*
2352                  * We use 48 bit ext4_inode i_blocks
2353                  * With EXT4_HUGE_FILE_FL set the i_blocks
2354                  * represent total number of blocks in
2355                  * file system block size
2356                  */
2357                 upper_limit = (1LL << 48) - 1;
2358
2359         }
2360
2361         /* indirect blocks */
2362         meta_blocks = 1;
2363         /* double indirect blocks */
2364         meta_blocks += 1 + (1LL << (bits-2));
2365         /* tripple indirect blocks */
2366         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2367
2368         upper_limit -= meta_blocks;
2369         upper_limit <<= bits;
2370
2371         res += 1LL << (bits-2);
2372         res += 1LL << (2*(bits-2));
2373         res += 1LL << (3*(bits-2));
2374         res <<= bits;
2375         if (res > upper_limit)
2376                 res = upper_limit;
2377
2378         if (res > MAX_LFS_FILESIZE)
2379                 res = MAX_LFS_FILESIZE;
2380
2381         return res;
2382 }
2383
2384 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2385                                    ext4_fsblk_t logical_sb_block, int nr)
2386 {
2387         struct ext4_sb_info *sbi = EXT4_SB(sb);
2388         ext4_group_t bg, first_meta_bg;
2389         int has_super = 0;
2390
2391         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2392
2393         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2394             nr < first_meta_bg)
2395                 return logical_sb_block + nr + 1;
2396         bg = sbi->s_desc_per_block * nr;
2397         if (ext4_bg_has_super(sb, bg))
2398                 has_super = 1;
2399
2400         /*
2401          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2402          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2403          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2404          * compensate.
2405          */
2406         if (sb->s_blocksize == 1024 && nr == 0 &&
2407             le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) == 0)
2408                 has_super++;
2409
2410         return (has_super + ext4_group_first_block_no(sb, bg));
2411 }
2412
2413 /**
2414  * ext4_get_stripe_size: Get the stripe size.
2415  * @sbi: In memory super block info
2416  *
2417  * If we have specified it via mount option, then
2418  * use the mount option value. If the value specified at mount time is
2419  * greater than the blocks per group use the super block value.
2420  * If the super block value is greater than blocks per group return 0.
2421  * Allocator needs it be less than blocks per group.
2422  *
2423  */
2424 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2425 {
2426         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2427         unsigned long stripe_width =
2428                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2429         int ret;
2430
2431         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2432                 ret = sbi->s_stripe;
2433         else if (stripe_width <= sbi->s_blocks_per_group)
2434                 ret = stripe_width;
2435         else if (stride <= sbi->s_blocks_per_group)
2436                 ret = stride;
2437         else
2438                 ret = 0;
2439
2440         /*
2441          * If the stripe width is 1, this makes no sense and
2442          * we set it to 0 to turn off stripe handling code.
2443          */
2444         if (ret <= 1)
2445                 ret = 0;
2446
2447         return ret;
2448 }
2449
2450 /*
2451  * Check whether this filesystem can be mounted based on
2452  * the features present and the RDONLY/RDWR mount requested.
2453  * Returns 1 if this filesystem can be mounted as requested,
2454  * 0 if it cannot be.
2455  */
2456 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2457 {
2458         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2459                 ext4_msg(sb, KERN_ERR,
2460                         "Couldn't mount because of "
2461                         "unsupported optional features (%x)",
2462                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2463                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2464                 return 0;
2465         }
2466
2467         if (readonly)
2468                 return 1;
2469
2470         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_READONLY)) {
2471                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2472                 sb->s_flags |= MS_RDONLY;
2473                 return 1;
2474         }
2475
2476         /* Check that feature set is OK for a read-write mount */
2477         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2478                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2479                          "unsupported optional features (%x)",
2480                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2481                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2482                 return 0;
2483         }
2484         /*
2485          * Large file size enabled file system can only be mounted
2486          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2487          */
2488         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2489                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2490                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2491                                  "cannot be mounted RDWR without "
2492                                  "CONFIG_LBDAF");
2493                         return 0;
2494                 }
2495         }
2496         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2497             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2498                 ext4_msg(sb, KERN_ERR,
2499                          "Can't support bigalloc feature without "
2500                          "extents feature\n");
2501                 return 0;
2502         }
2503
2504 #ifndef CONFIG_QUOTA
2505         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
2506             !readonly) {
2507                 ext4_msg(sb, KERN_ERR,
2508                          "Filesystem with quota feature cannot be mounted RDWR "
2509                          "without CONFIG_QUOTA");
2510                 return 0;
2511         }
2512 #endif  /* CONFIG_QUOTA */
2513         return 1;
2514 }
2515
2516 /*
2517  * This function is called once a day if we have errors logged
2518  * on the file system
2519  */
2520 static void print_daily_error_info(unsigned long arg)
2521 {
2522         struct super_block *sb = (struct super_block *) arg;
2523         struct ext4_sb_info *sbi;
2524         struct ext4_super_block *es;
2525
2526         sbi = EXT4_SB(sb);
2527         es = sbi->s_es;
2528
2529         if (es->s_error_count)
2530                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2531                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2532                          le32_to_cpu(es->s_error_count));
2533         if (es->s_first_error_time) {
2534                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2535                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2536                        (int) sizeof(es->s_first_error_func),
2537                        es->s_first_error_func,
2538                        le32_to_cpu(es->s_first_error_line));
2539                 if (es->s_first_error_ino)
2540                         printk(": inode %u",
2541                                le32_to_cpu(es->s_first_error_ino));
2542                 if (es->s_first_error_block)
2543                         printk(": block %llu", (unsigned long long)
2544                                le64_to_cpu(es->s_first_error_block));
2545                 printk("\n");
2546         }
2547         if (es->s_last_error_time) {
2548                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2549                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2550                        (int) sizeof(es->s_last_error_func),
2551                        es->s_last_error_func,
2552                        le32_to_cpu(es->s_last_error_line));
2553                 if (es->s_last_error_ino)
2554                         printk(": inode %u",
2555                                le32_to_cpu(es->s_last_error_ino));
2556                 if (es->s_last_error_block)
2557                         printk(": block %llu", (unsigned long long)
2558                                le64_to_cpu(es->s_last_error_block));
2559                 printk("\n");
2560         }
2561         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2562 }
2563
2564 /* Find next suitable group and run ext4_init_inode_table */
2565 static int ext4_run_li_request(struct ext4_li_request *elr)
2566 {
2567         struct ext4_group_desc *gdp = NULL;
2568         ext4_group_t group, ngroups;
2569         struct super_block *sb;
2570         unsigned long timeout = 0;
2571         int ret = 0;
2572
2573         sb = elr->lr_super;
2574         ngroups = EXT4_SB(sb)->s_groups_count;
2575
2576         sb_start_write(sb);
2577         for (group = elr->lr_next_group; group < ngroups; group++) {
2578                 gdp = ext4_get_group_desc(sb, group, NULL);
2579                 if (!gdp) {
2580                         ret = 1;
2581                         break;
2582                 }
2583
2584                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2585                         break;
2586         }
2587
2588         if (group >= ngroups)
2589                 ret = 1;
2590
2591         if (!ret) {
2592                 timeout = jiffies;
2593                 ret = ext4_init_inode_table(sb, group,
2594                                             elr->lr_timeout ? 0 : 1);
2595                 if (elr->lr_timeout == 0) {
2596                         timeout = (jiffies - timeout) *
2597                                   elr->lr_sbi->s_li_wait_mult;
2598                         elr->lr_timeout = timeout;
2599                 }
2600                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2601                 elr->lr_next_group = group + 1;
2602         }
2603         sb_end_write(sb);
2604
2605         return ret;
2606 }
2607
2608 /*
2609  * Remove lr_request from the list_request and free the
2610  * request structure. Should be called with li_list_mtx held
2611  */
2612 static void ext4_remove_li_request(struct ext4_li_request *elr)
2613 {
2614         struct ext4_sb_info *sbi;
2615
2616         if (!elr)
2617                 return;
2618
2619         sbi = elr->lr_sbi;
2620
2621         list_del(&elr->lr_request);
2622         sbi->s_li_request = NULL;
2623         kfree(elr);
2624 }
2625
2626 static void ext4_unregister_li_request(struct super_block *sb)
2627 {
2628         mutex_lock(&ext4_li_mtx);
2629         if (!ext4_li_info) {
2630                 mutex_unlock(&ext4_li_mtx);
2631                 return;
2632         }
2633
2634         mutex_lock(&ext4_li_info->li_list_mtx);
2635         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2636         mutex_unlock(&ext4_li_info->li_list_mtx);
2637         mutex_unlock(&ext4_li_mtx);
2638 }
2639
2640 static struct task_struct *ext4_lazyinit_task;
2641
2642 /*
2643  * This is the function where ext4lazyinit thread lives. It walks
2644  * through the request list searching for next scheduled filesystem.
2645  * When such a fs is found, run the lazy initialization request
2646  * (ext4_rn_li_request) and keep track of the time spend in this
2647  * function. Based on that time we compute next schedule time of
2648  * the request. When walking through the list is complete, compute
2649  * next waking time and put itself into sleep.
2650  */
2651 static int ext4_lazyinit_thread(void *arg)
2652 {
2653         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2654         struct list_head *pos, *n;
2655         struct ext4_li_request *elr;
2656         unsigned long next_wakeup, cur;
2657
2658         BUG_ON(NULL == eli);
2659
2660 cont_thread:
2661         while (true) {
2662                 next_wakeup = MAX_JIFFY_OFFSET;
2663
2664                 mutex_lock(&eli->li_list_mtx);
2665                 if (list_empty(&eli->li_request_list)) {
2666                         mutex_unlock(&eli->li_list_mtx);
2667                         goto exit_thread;
2668                 }
2669
2670                 list_for_each_safe(pos, n, &eli->li_request_list) {
2671                         elr = list_entry(pos, struct ext4_li_request,
2672                                          lr_request);
2673
2674                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2675                                 if (ext4_run_li_request(elr) != 0) {
2676                                         /* error, remove the lazy_init job */
2677                                         ext4_remove_li_request(elr);
2678                                         continue;
2679                                 }
2680                         }
2681
2682                         if (time_before(elr->lr_next_sched, next_wakeup))
2683                                 next_wakeup = elr->lr_next_sched;
2684                 }
2685                 mutex_unlock(&eli->li_list_mtx);
2686
2687                 try_to_freeze();
2688
2689                 cur = jiffies;
2690                 if ((time_after_eq(cur, next_wakeup)) ||
2691                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2692                         cond_resched();
2693                         continue;
2694                 }
2695
2696                 schedule_timeout_interruptible(next_wakeup - cur);
2697
2698                 if (kthread_should_stop()) {
2699                         ext4_clear_request_list();
2700                         goto exit_thread;
2701                 }
2702         }
2703
2704 exit_thread:
2705         /*
2706          * It looks like the request list is empty, but we need
2707          * to check it under the li_list_mtx lock, to prevent any
2708          * additions into it, and of course we should lock ext4_li_mtx
2709          * to atomically free the list and ext4_li_info, because at
2710          * this point another ext4 filesystem could be registering
2711          * new one.
2712          */
2713         mutex_lock(&ext4_li_mtx);
2714         mutex_lock(&eli->li_list_mtx);
2715         if (!list_empty(&eli->li_request_list)) {
2716                 mutex_unlock(&eli->li_list_mtx);
2717                 mutex_unlock(&ext4_li_mtx);
2718                 goto cont_thread;
2719         }
2720         mutex_unlock(&eli->li_list_mtx);
2721         kfree(ext4_li_info);
2722         ext4_li_info = NULL;
2723         mutex_unlock(&ext4_li_mtx);
2724
2725         return 0;
2726 }
2727
2728 static void ext4_clear_request_list(void)
2729 {
2730         struct list_head *pos, *n;
2731         struct ext4_li_request *elr;
2732
2733         mutex_lock(&ext4_li_info->li_list_mtx);
2734         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2735                 elr = list_entry(pos, struct ext4_li_request,
2736                                  lr_request);
2737                 ext4_remove_li_request(elr);
2738         }
2739         mutex_unlock(&ext4_li_info->li_list_mtx);
2740 }
2741
2742 static int ext4_run_lazyinit_thread(void)
2743 {
2744         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2745                                          ext4_li_info, "ext4lazyinit");
2746         if (IS_ERR(ext4_lazyinit_task)) {
2747                 int err = PTR_ERR(ext4_lazyinit_task);
2748                 ext4_clear_request_list();
2749                 kfree(ext4_li_info);
2750                 ext4_li_info = NULL;
2751                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
2752                                  "initialization thread\n",
2753                                  err);
2754                 return err;
2755         }
2756         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2757         return 0;
2758 }
2759
2760 /*
2761  * Check whether it make sense to run itable init. thread or not.
2762  * If there is at least one uninitialized inode table, return
2763  * corresponding group number, else the loop goes through all
2764  * groups and return total number of groups.
2765  */
2766 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2767 {
2768         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2769         struct ext4_group_desc *gdp = NULL;
2770
2771         for (group = 0; group < ngroups; group++) {
2772                 gdp = ext4_get_group_desc(sb, group, NULL);
2773                 if (!gdp)
2774                         continue;
2775
2776                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2777                         break;
2778         }
2779
2780         return group;
2781 }
2782
2783 static int ext4_li_info_new(void)
2784 {
2785         struct ext4_lazy_init *eli = NULL;
2786
2787         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2788         if (!eli)
2789                 return -ENOMEM;
2790
2791         INIT_LIST_HEAD(&eli->li_request_list);
2792         mutex_init(&eli->li_list_mtx);
2793
2794         eli->li_state |= EXT4_LAZYINIT_QUIT;
2795
2796         ext4_li_info = eli;
2797
2798         return 0;
2799 }
2800
2801 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2802                                             ext4_group_t start)
2803 {
2804         struct ext4_sb_info *sbi = EXT4_SB(sb);
2805         struct ext4_li_request *elr;
2806
2807         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2808         if (!elr)
2809                 return NULL;
2810
2811         elr->lr_super = sb;
2812         elr->lr_sbi = sbi;
2813         elr->lr_next_group = start;
2814
2815         /*
2816          * Randomize first schedule time of the request to
2817          * spread the inode table initialization requests
2818          * better.
2819          */
2820         elr->lr_next_sched = jiffies + (prandom_u32() %
2821                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
2822         return elr;
2823 }
2824
2825 int ext4_register_li_request(struct super_block *sb,
2826                              ext4_group_t first_not_zeroed)
2827 {
2828         struct ext4_sb_info *sbi = EXT4_SB(sb);
2829         struct ext4_li_request *elr = NULL;
2830         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2831         int ret = 0;
2832
2833         mutex_lock(&ext4_li_mtx);
2834         if (sbi->s_li_request != NULL) {
2835                 /*
2836                  * Reset timeout so it can be computed again, because
2837                  * s_li_wait_mult might have changed.
2838                  */
2839                 sbi->s_li_request->lr_timeout = 0;
2840                 goto out;
2841         }
2842
2843         if (first_not_zeroed == ngroups ||
2844             (sb->s_flags & MS_RDONLY) ||
2845             !test_opt(sb, INIT_INODE_TABLE))
2846                 goto out;
2847
2848         elr = ext4_li_request_new(sb, first_not_zeroed);
2849         if (!elr) {
2850                 ret = -ENOMEM;
2851                 goto out;
2852         }
2853
2854         if (NULL == ext4_li_info) {
2855                 ret = ext4_li_info_new();
2856                 if (ret)
2857                         goto out;
2858         }
2859
2860         mutex_lock(&ext4_li_info->li_list_mtx);
2861         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
2862         mutex_unlock(&ext4_li_info->li_list_mtx);
2863
2864         sbi->s_li_request = elr;
2865         /*
2866          * set elr to NULL here since it has been inserted to
2867          * the request_list and the removal and free of it is
2868          * handled by ext4_clear_request_list from now on.
2869          */
2870         elr = NULL;
2871
2872         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
2873                 ret = ext4_run_lazyinit_thread();
2874                 if (ret)
2875                         goto out;
2876         }
2877 out:
2878         mutex_unlock(&ext4_li_mtx);
2879         if (ret)
2880                 kfree(elr);
2881         return ret;
2882 }
2883
2884 /*
2885  * We do not need to lock anything since this is called on
2886  * module unload.
2887  */
2888 static void ext4_destroy_lazyinit_thread(void)
2889 {
2890         /*
2891          * If thread exited earlier
2892          * there's nothing to be done.
2893          */
2894         if (!ext4_li_info || !ext4_lazyinit_task)
2895                 return;
2896
2897         kthread_stop(ext4_lazyinit_task);
2898 }
2899
2900 static int set_journal_csum_feature_set(struct super_block *sb)
2901 {
2902         int ret = 1;
2903         int compat, incompat;
2904         struct ext4_sb_info *sbi = EXT4_SB(sb);
2905
2906         if (ext4_has_metadata_csum(sb)) {
2907                 /* journal checksum v3 */
2908                 compat = 0;
2909                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
2910         } else {
2911                 /* journal checksum v1 */
2912                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
2913                 incompat = 0;
2914         }
2915
2916         jbd2_journal_clear_features(sbi->s_journal,
2917                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2918                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
2919                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
2920         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2921                 ret = jbd2_journal_set_features(sbi->s_journal,
2922                                 compat, 0,
2923                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
2924                                 incompat);
2925         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2926                 ret = jbd2_journal_set_features(sbi->s_journal,
2927                                 compat, 0,
2928                                 incompat);
2929                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2930                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2931         } else {
2932                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2933                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2934         }
2935
2936         return ret;
2937 }
2938
2939 /*
2940  * Note: calculating the overhead so we can be compatible with
2941  * historical BSD practice is quite difficult in the face of
2942  * clusters/bigalloc.  This is because multiple metadata blocks from
2943  * different block group can end up in the same allocation cluster.
2944  * Calculating the exact overhead in the face of clustered allocation
2945  * requires either O(all block bitmaps) in memory or O(number of block
2946  * groups**2) in time.  We will still calculate the superblock for
2947  * older file systems --- and if we come across with a bigalloc file
2948  * system with zero in s_overhead_clusters the estimate will be close to
2949  * correct especially for very large cluster sizes --- but for newer
2950  * file systems, it's better to calculate this figure once at mkfs
2951  * time, and store it in the superblock.  If the superblock value is
2952  * present (even for non-bigalloc file systems), we will use it.
2953  */
2954 static int count_overhead(struct super_block *sb, ext4_group_t grp,
2955                           char *buf)
2956 {
2957         struct ext4_sb_info     *sbi = EXT4_SB(sb);
2958         struct ext4_group_desc  *gdp;
2959         ext4_fsblk_t            first_block, last_block, b;
2960         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
2961         int                     s, j, count = 0;
2962
2963         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC))
2964                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
2965                         sbi->s_itb_per_group + 2);
2966
2967         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
2968                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
2969         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
2970         for (i = 0; i < ngroups; i++) {
2971                 gdp = ext4_get_group_desc(sb, i, NULL);
2972                 b = ext4_block_bitmap(sb, gdp);
2973                 if (b >= first_block && b <= last_block) {
2974                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
2975                         count++;
2976                 }
2977                 b = ext4_inode_bitmap(sb, gdp);
2978                 if (b >= first_block && b <= last_block) {
2979                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
2980                         count++;
2981                 }
2982                 b = ext4_inode_table(sb, gdp);
2983                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
2984                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
2985                                 int c = EXT4_B2C(sbi, b - first_block);
2986                                 ext4_set_bit(c, buf);
2987                                 count++;
2988                         }
2989                 if (i != grp)
2990                         continue;
2991                 s = 0;
2992                 if (ext4_bg_has_super(sb, grp)) {
2993                         ext4_set_bit(s++, buf);
2994                         count++;
2995                 }
2996                 for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
2997                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
2998                         count++;
2999                 }
3000         }
3001         if (!count)
3002                 return 0;
3003         return EXT4_CLUSTERS_PER_GROUP(sb) -
3004                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3005 }
3006
3007 /*
3008  * Compute the overhead and stash it in sbi->s_overhead
3009  */
3010 int ext4_calculate_overhead(struct super_block *sb)
3011 {
3012         struct ext4_sb_info *sbi = EXT4_SB(sb);
3013         struct ext4_super_block *es = sbi->s_es;
3014         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3015         ext4_fsblk_t overhead = 0;
3016         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3017
3018         if (!buf)
3019                 return -ENOMEM;
3020
3021         /*
3022          * Compute the overhead (FS structures).  This is constant
3023          * for a given filesystem unless the number of block groups
3024          * changes so we cache the previous value until it does.
3025          */
3026
3027         /*
3028          * All of the blocks before first_data_block are overhead
3029          */
3030         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3031
3032         /*
3033          * Add the overhead found in each block group
3034          */
3035         for (i = 0; i < ngroups; i++) {
3036                 int blks;
3037
3038                 blks = count_overhead(sb, i, buf);
3039                 overhead += blks;
3040                 if (blks)
3041                         memset(buf, 0, PAGE_SIZE);
3042                 cond_resched();
3043         }
3044         /* Add the internal journal blocks as well */
3045         if (sbi->s_journal && !sbi->journal_bdev)
3046                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3047
3048         sbi->s_overhead = overhead;
3049         smp_wmb();
3050         free_page((unsigned long) buf);
3051         return 0;
3052 }
3053
3054 static void ext4_set_resv_clusters(struct super_block *sb)
3055 {
3056         ext4_fsblk_t resv_clusters;
3057         struct ext4_sb_info *sbi = EXT4_SB(sb);
3058
3059         /*
3060          * There's no need to reserve anything when we aren't using extents.
3061          * The space estimates are exact, there are no unwritten extents,
3062          * hole punching doesn't need new metadata... This is needed especially
3063          * to keep ext2/3 backward compatibility.
3064          */
3065         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
3066                 return;
3067         /*
3068          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3069          * This should cover the situations where we can not afford to run
3070          * out of space like for example punch hole, or converting
3071          * unwritten extents in delalloc path. In most cases such
3072          * allocation would require 1, or 2 blocks, higher numbers are
3073          * very rare.
3074          */
3075         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3076                          sbi->s_cluster_bits);
3077
3078         do_div(resv_clusters, 50);
3079         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3080
3081         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3082 }
3083
3084 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3085 {
3086         char *orig_data = kstrdup(data, GFP_KERNEL);
3087         struct buffer_head *bh;
3088         struct ext4_super_block *es = NULL;
3089         struct ext4_sb_info *sbi;
3090         ext4_fsblk_t block;
3091         ext4_fsblk_t sb_block = get_sb_block(&data);
3092         ext4_fsblk_t logical_sb_block;
3093         unsigned long offset = 0;
3094         unsigned long journal_devnum = 0;
3095         unsigned long def_mount_opts;
3096         struct inode *root;
3097         const char *descr;
3098         int ret = -ENOMEM;
3099         int blocksize, clustersize;
3100         unsigned int db_count;
3101         unsigned int i;
3102         int needs_recovery, has_huge_files, has_bigalloc;
3103         __u64 blocks_count;
3104         int err = 0;
3105         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3106         ext4_group_t first_not_zeroed;
3107
3108         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3109         if (!sbi)
3110                 goto out_free_orig;
3111
3112         sbi->s_blockgroup_lock =
3113                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3114         if (!sbi->s_blockgroup_lock) {
3115                 kfree(sbi);
3116                 goto out_free_orig;
3117         }
3118         sb->s_fs_info = sbi;
3119         sbi->s_sb = sb;
3120         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3121         sbi->s_sb_block = sb_block;
3122         if (sb->s_bdev->bd_part)
3123                 sbi->s_sectors_written_start =
3124                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3125
3126         /* Cleanup superblock name */
3127         strreplace(sb->s_id, '/', '!');
3128
3129         /* -EINVAL is default */
3130         ret = -EINVAL;
3131         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3132         if (!blocksize) {
3133                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3134                 goto out_fail;
3135         }
3136
3137         /*
3138          * The ext4 superblock will not be buffer aligned for other than 1kB
3139          * block sizes.  We need to calculate the offset from buffer start.
3140          */
3141         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3142                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3143                 offset = do_div(logical_sb_block, blocksize);
3144         } else {
3145                 logical_sb_block = sb_block;
3146         }
3147
3148         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3149                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3150                 goto out_fail;
3151         }
3152         /*
3153          * Note: s_es must be initialized as soon as possible because
3154          *       some ext4 macro-instructions depend on its value
3155          */
3156         es = (struct ext4_super_block *) (bh->b_data + offset);
3157         sbi->s_es = es;
3158         sb->s_magic = le16_to_cpu(es->s_magic);
3159         if (sb->s_magic != EXT4_SUPER_MAGIC)
3160                 goto cantfind_ext4;
3161         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3162
3163         /* Warn if metadata_csum and gdt_csum are both set. */
3164         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3165                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
3166             EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
3167                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3168                              "redundant flags; please run fsck.");
3169
3170         /* Check for a known checksum algorithm */
3171         if (!ext4_verify_csum_type(sb, es)) {
3172                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3173                          "unknown checksum algorithm.");
3174                 silent = 1;
3175                 goto cantfind_ext4;
3176         }
3177
3178         /* Load the checksum driver */
3179         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3180                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3181                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3182                 if (IS_ERR(sbi->s_chksum_driver)) {
3183                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3184                         ret = PTR_ERR(sbi->s_chksum_driver);
3185                         sbi->s_chksum_driver = NULL;
3186                         goto failed_mount;
3187                 }
3188         }
3189
3190         /* Check superblock checksum */
3191         if (!ext4_superblock_csum_verify(sb, es)) {
3192                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3193                          "invalid superblock checksum.  Run e2fsck?");
3194                 silent = 1;
3195                 goto cantfind_ext4;
3196         }
3197
3198         /* Precompute checksum seed for all metadata */
3199         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_CSUM_SEED))
3200                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3201         else if (ext4_has_metadata_csum(sb))
3202                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3203                                                sizeof(es->s_uuid));
3204
3205         /* Set defaults before we parse the mount options */
3206         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3207         set_opt(sb, INIT_INODE_TABLE);
3208         if (def_mount_opts & EXT4_DEFM_DEBUG)
3209                 set_opt(sb, DEBUG);
3210         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3211                 set_opt(sb, GRPID);
3212         if (def_mount_opts & EXT4_DEFM_UID16)
3213                 set_opt(sb, NO_UID32);
3214         /* xattr user namespace & acls are now defaulted on */
3215         set_opt(sb, XATTR_USER);
3216 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3217         set_opt(sb, POSIX_ACL);
3218 #endif
3219         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3220         if (ext4_has_metadata_csum(sb))
3221                 set_opt(sb, JOURNAL_CHECKSUM);
3222
3223         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3224                 set_opt(sb, JOURNAL_DATA);
3225         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3226                 set_opt(sb, ORDERED_DATA);
3227         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3228                 set_opt(sb, WRITEBACK_DATA);
3229
3230         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3231                 set_opt(sb, ERRORS_PANIC);
3232         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3233                 set_opt(sb, ERRORS_CONT);
3234         else
3235                 set_opt(sb, ERRORS_RO);
3236         /* block_validity enabled by default; disable with noblock_validity */
3237         set_opt(sb, BLOCK_VALIDITY);
3238         if (def_mount_opts & EXT4_DEFM_DISCARD)
3239                 set_opt(sb, DISCARD);
3240
3241         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3242         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3243         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3244         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3245         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3246
3247         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3248                 set_opt(sb, BARRIER);
3249
3250         /*
3251          * enable delayed allocation by default
3252          * Use -o nodelalloc to turn it off
3253          */
3254         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3255             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3256                 set_opt(sb, DELALLOC);
3257
3258         /*
3259          * set default s_li_wait_mult for lazyinit, for the case there is
3260          * no mount option specified.
3261          */
3262         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3263
3264         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3265                            &journal_devnum, &journal_ioprio, 0)) {
3266                 ext4_msg(sb, KERN_WARNING,
3267                          "failed to parse options in superblock: %s",
3268                          sbi->s_es->s_mount_opts);
3269         }
3270         sbi->s_def_mount_opt = sbi->s_mount_opt;
3271         if (!parse_options((char *) data, sb, &journal_devnum,
3272                            &journal_ioprio, 0))
3273                 goto failed_mount;
3274
3275         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3276                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3277                             "with data=journal disables delayed "
3278                             "allocation and O_DIRECT support!\n");
3279                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3280                         ext4_msg(sb, KERN_ERR, "can't mount with "
3281                                  "both data=journal and delalloc");
3282                         goto failed_mount;
3283                 }
3284                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3285                         ext4_msg(sb, KERN_ERR, "can't mount with "
3286                                  "both data=journal and dioread_nolock");
3287                         goto failed_mount;
3288                 }
3289                 if (test_opt(sb, DAX)) {
3290                         ext4_msg(sb, KERN_ERR, "can't mount with "
3291                                  "both data=journal and dax");
3292                         goto failed_mount;
3293                 }
3294                 if (test_opt(sb, DELALLOC))
3295                         clear_opt(sb, DELALLOC);
3296         } else {
3297                 sb->s_iflags |= SB_I_CGROUPWB;
3298         }
3299
3300         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3301                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3302
3303         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3304             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3305              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3306              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3307                 ext4_msg(sb, KERN_WARNING,
3308                        "feature flags set on rev 0 fs, "
3309                        "running e2fsck is recommended");
3310
3311         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3312                 set_opt2(sb, HURD_COMPAT);
3313                 if (EXT4_HAS_INCOMPAT_FEATURE(sb,
3314                                               EXT4_FEATURE_INCOMPAT_64BIT)) {
3315                         ext4_msg(sb, KERN_ERR,
3316                                  "The Hurd can't support 64-bit file systems");
3317                         goto failed_mount;
3318                 }
3319         }
3320
3321         if (IS_EXT2_SB(sb)) {
3322                 if (ext2_feature_set_ok(sb))
3323                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3324                                  "using the ext4 subsystem");
3325                 else {
3326                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3327                                  "to feature incompatibilities");
3328                         goto failed_mount;
3329                 }
3330         }
3331
3332         if (IS_EXT3_SB(sb)) {
3333                 if (ext3_feature_set_ok(sb))
3334                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3335                                  "using the ext4 subsystem");
3336                 else {
3337                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3338                                  "to feature incompatibilities");
3339                         goto failed_mount;
3340                 }
3341         }
3342
3343         /*
3344          * Check feature flags regardless of the revision level, since we
3345          * previously didn't change the revision level when setting the flags,
3346          * so there is a chance incompat flags are set on a rev 0 filesystem.
3347          */
3348         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3349                 goto failed_mount;
3350
3351         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3352         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3353             blocksize > EXT4_MAX_BLOCK_SIZE) {
3354                 ext4_msg(sb, KERN_ERR,
3355                        "Unsupported filesystem blocksize %d", blocksize);
3356                 goto failed_mount;
3357         }
3358
3359         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3360                 if (blocksize != PAGE_SIZE) {
3361                         ext4_msg(sb, KERN_ERR,
3362                                         "error: unsupported blocksize for dax");
3363                         goto failed_mount;
3364                 }
3365                 if (!sb->s_bdev->bd_disk->fops->direct_access) {
3366                         ext4_msg(sb, KERN_ERR,
3367                                         "error: device does not support dax");
3368                         goto failed_mount;
3369                 }
3370         }
3371
3372         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT) &&
3373             es->s_encryption_level) {
3374                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3375                          es->s_encryption_level);
3376                 goto failed_mount;
3377         }
3378
3379         if (sb->s_blocksize != blocksize) {
3380                 /* Validate the filesystem blocksize */
3381                 if (!sb_set_blocksize(sb, blocksize)) {
3382                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3383                                         blocksize);
3384                         goto failed_mount;
3385                 }
3386
3387                 brelse(bh);
3388                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3389                 offset = do_div(logical_sb_block, blocksize);
3390                 bh = sb_bread_unmovable(sb, logical_sb_block);
3391                 if (!bh) {
3392                         ext4_msg(sb, KERN_ERR,
3393                                "Can't read superblock on 2nd try");
3394                         goto failed_mount;
3395                 }
3396                 es = (struct ext4_super_block *)(bh->b_data + offset);
3397                 sbi->s_es = es;
3398                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3399                         ext4_msg(sb, KERN_ERR,
3400                                "Magic mismatch, very weird!");
3401                         goto failed_mount;
3402                 }
3403         }
3404
3405         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3406                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3407         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3408                                                       has_huge_files);
3409         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3410
3411         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3412                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3413                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3414         } else {
3415                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3416                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3417                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3418                     (!is_power_of_2(sbi->s_inode_size)) ||
3419                     (sbi->s_inode_size > blocksize)) {
3420                         ext4_msg(sb, KERN_ERR,
3421                                "unsupported inode size: %d",
3422                                sbi->s_inode_size);
3423                         goto failed_mount;
3424                 }
3425                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3426                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3427         }
3428
3429         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3430         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3431                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3432                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3433                     !is_power_of_2(sbi->s_desc_size)) {
3434                         ext4_msg(sb, KERN_ERR,
3435                                "unsupported descriptor size %lu",
3436                                sbi->s_desc_size);
3437                         goto failed_mount;
3438                 }
3439         } else
3440                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3441
3442         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3443         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3444         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3445                 goto cantfind_ext4;
3446
3447         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3448         if (sbi->s_inodes_per_block == 0)
3449                 goto cantfind_ext4;
3450         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3451                                         sbi->s_inodes_per_block;
3452         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3453         sbi->s_sbh = bh;
3454         sbi->s_mount_state = le16_to_cpu(es->s_state);
3455         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3456         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3457
3458         for (i = 0; i < 4; i++)
3459                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3460         sbi->s_def_hash_version = es->s_def_hash_version;
3461         if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX)) {
3462                 i = le32_to_cpu(es->s_flags);
3463                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
3464                         sbi->s_hash_unsigned = 3;
3465                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3466 #ifdef __CHAR_UNSIGNED__
3467                         if (!(sb->s_flags & MS_RDONLY))
3468                                 es->s_flags |=
3469                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3470                         sbi->s_hash_unsigned = 3;
3471 #else
3472                         if (!(sb->s_flags & MS_RDONLY))
3473                                 es->s_flags |=
3474                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3475 #endif
3476                 }
3477         }
3478
3479         /* Handle clustersize */
3480         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3481         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3482                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3483         if (has_bigalloc) {
3484                 if (clustersize < blocksize) {
3485                         ext4_msg(sb, KERN_ERR,
3486                                  "cluster size (%d) smaller than "
3487                                  "block size (%d)", clustersize, blocksize);
3488                         goto failed_mount;
3489                 }
3490                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3491                         le32_to_cpu(es->s_log_block_size);
3492                 sbi->s_clusters_per_group =
3493                         le32_to_cpu(es->s_clusters_per_group);
3494                 if (sbi->s_clusters_per_group > blocksize * 8) {
3495                         ext4_msg(sb, KERN_ERR,
3496                                  "#clusters per group too big: %lu",
3497                                  sbi->s_clusters_per_group);
3498                         goto failed_mount;
3499                 }
3500                 if (sbi->s_blocks_per_group !=
3501                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3502                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3503                                  "clusters per group (%lu) inconsistent",
3504                                  sbi->s_blocks_per_group,
3505                                  sbi->s_clusters_per_group);
3506                         goto failed_mount;
3507                 }
3508         } else {
3509                 if (clustersize != blocksize) {
3510                         ext4_warning(sb, "fragment/cluster size (%d) != "
3511                                      "block size (%d)", clustersize,
3512                                      blocksize);
3513                         clustersize = blocksize;
3514                 }
3515                 if (sbi->s_blocks_per_group > blocksize * 8) {
3516                         ext4_msg(sb, KERN_ERR,
3517                                  "#blocks per group too big: %lu",
3518                                  sbi->s_blocks_per_group);
3519                         goto failed_mount;
3520                 }
3521                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3522                 sbi->s_cluster_bits = 0;
3523         }
3524         sbi->s_cluster_ratio = clustersize / blocksize;
3525
3526         if (sbi->s_inodes_per_group > blocksize * 8) {
3527                 ext4_msg(sb, KERN_ERR,
3528                        "#inodes per group too big: %lu",
3529                        sbi->s_inodes_per_group);
3530                 goto failed_mount;
3531         }
3532
3533         /* Do we have standard group size of clustersize * 8 blocks ? */
3534         if (sbi->s_blocks_per_group == clustersize << 3)
3535                 set_opt2(sb, STD_GROUP_SIZE);
3536
3537         /*
3538          * Test whether we have more sectors than will fit in sector_t,
3539          * and whether the max offset is addressable by the page cache.
3540          */
3541         err = generic_check_addressable(sb->s_blocksize_bits,
3542                                         ext4_blocks_count(es));
3543         if (err) {
3544                 ext4_msg(sb, KERN_ERR, "filesystem"
3545                          " too large to mount safely on this system");
3546                 if (sizeof(sector_t) < 8)
3547                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3548                 goto failed_mount;
3549         }
3550
3551         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3552                 goto cantfind_ext4;
3553
3554         /* check blocks count against device size */
3555         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3556         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3557                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3558                        "exceeds size of device (%llu blocks)",
3559                        ext4_blocks_count(es), blocks_count);
3560                 goto failed_mount;
3561         }
3562
3563         /*
3564          * It makes no sense for the first data block to be beyond the end
3565          * of the filesystem.
3566          */
3567         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3568                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3569                          "block %u is beyond end of filesystem (%llu)",
3570                          le32_to_cpu(es->s_first_data_block),
3571                          ext4_blocks_count(es));
3572                 goto failed_mount;
3573         }
3574         blocks_count = (ext4_blocks_count(es) -
3575                         le32_to_cpu(es->s_first_data_block) +
3576                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3577         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3578         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3579                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3580                        "(block count %llu, first data block %u, "
3581                        "blocks per group %lu)", sbi->s_groups_count,
3582                        ext4_blocks_count(es),
3583                        le32_to_cpu(es->s_first_data_block),
3584                        EXT4_BLOCKS_PER_GROUP(sb));
3585                 goto failed_mount;
3586         }
3587         sbi->s_groups_count = blocks_count;
3588         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3589                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3590         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3591                    EXT4_DESC_PER_BLOCK(sb);
3592         sbi->s_group_desc = ext4_kvmalloc(db_count *
3593                                           sizeof(struct buffer_head *),
3594                                           GFP_KERNEL);
3595         if (sbi->s_group_desc == NULL) {
3596                 ext4_msg(sb, KERN_ERR, "not enough memory");
3597                 ret = -ENOMEM;
3598                 goto failed_mount;
3599         }
3600
3601         bgl_lock_init(sbi->s_blockgroup_lock);
3602
3603         for (i = 0; i < db_count; i++) {
3604                 block = descriptor_loc(sb, logical_sb_block, i);
3605                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
3606                 if (!sbi->s_group_desc[i]) {
3607                         ext4_msg(sb, KERN_ERR,
3608                                "can't read group descriptor %d", i);
3609                         db_count = i;
3610                         goto failed_mount2;
3611                 }
3612         }
3613         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3614                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3615                 goto failed_mount2;
3616         }
3617
3618         sbi->s_gdb_count = db_count;
3619         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3620         spin_lock_init(&sbi->s_next_gen_lock);
3621
3622         setup_timer(&sbi->s_err_report, print_daily_error_info,
3623                 (unsigned long) sb);
3624
3625         /* Register extent status tree shrinker */
3626         if (ext4_es_register_shrinker(sbi))
3627                 goto failed_mount3;
3628
3629         sbi->s_stripe = ext4_get_stripe_size(sbi);
3630         sbi->s_extent_max_zeroout_kb = 32;
3631
3632         /*
3633          * set up enough so that it can read an inode
3634          */
3635         sb->s_op = &ext4_sops;
3636         sb->s_export_op = &ext4_export_ops;
3637         sb->s_xattr = ext4_xattr_handlers;
3638 #ifdef CONFIG_QUOTA
3639         sb->dq_op = &ext4_quota_operations;
3640         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
3641                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
3642         else
3643                 sb->s_qcop = &ext4_qctl_operations;
3644         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
3645 #endif
3646         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3647
3648         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3649         mutex_init(&sbi->s_orphan_lock);
3650
3651         sb->s_root = NULL;
3652
3653         needs_recovery = (es->s_last_orphan != 0 ||
3654                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3655                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3656
3657         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3658             !(sb->s_flags & MS_RDONLY))
3659                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3660                         goto failed_mount3a;
3661
3662         /*
3663          * The first inode we look at is the journal inode.  Don't try
3664          * root first: it may be modified in the journal!
3665          */
3666         if (!test_opt(sb, NOLOAD) &&
3667             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3668                 if (ext4_load_journal(sb, es, journal_devnum))
3669                         goto failed_mount3a;
3670         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3671               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3672                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3673                        "suppressed and not mounted read-only");
3674                 goto failed_mount_wq;
3675         } else {
3676                 clear_opt(sb, DATA_FLAGS);
3677                 sbi->s_journal = NULL;
3678                 needs_recovery = 0;
3679                 goto no_journal;
3680         }
3681
3682         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) &&
3683             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3684                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3685                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3686                 goto failed_mount_wq;
3687         }
3688
3689         if (!set_journal_csum_feature_set(sb)) {
3690                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
3691                          "feature set");
3692                 goto failed_mount_wq;
3693         }
3694
3695         /* We have now updated the journal if required, so we can
3696          * validate the data journaling mode. */
3697         switch (test_opt(sb, DATA_FLAGS)) {
3698         case 0:
3699                 /* No mode set, assume a default based on the journal
3700                  * capabilities: ORDERED_DATA if the journal can
3701                  * cope, else JOURNAL_DATA
3702                  */
3703                 if (jbd2_journal_check_available_features
3704                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3705                         set_opt(sb, ORDERED_DATA);
3706                 else
3707                         set_opt(sb, JOURNAL_DATA);
3708                 break;
3709
3710         case EXT4_MOUNT_ORDERED_DATA:
3711         case EXT4_MOUNT_WRITEBACK_DATA:
3712                 if (!jbd2_journal_check_available_features
3713                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3714                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3715                                "requested data journaling mode");
3716                         goto failed_mount_wq;
3717                 }
3718         default:
3719                 break;
3720         }
3721         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3722
3723         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
3724
3725 no_journal:
3726         if (ext4_mballoc_ready) {
3727                 sbi->s_mb_cache = ext4_xattr_create_cache(sb->s_id);
3728                 if (!sbi->s_mb_cache) {
3729                         ext4_msg(sb, KERN_ERR, "Failed to create an mb_cache");
3730                         goto failed_mount_wq;
3731                 }
3732         }
3733
3734         if ((DUMMY_ENCRYPTION_ENABLED(sbi) ||
3735              EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT)) &&
3736             (blocksize != PAGE_CACHE_SIZE)) {
3737                 ext4_msg(sb, KERN_ERR,
3738                          "Unsupported blocksize for fs encryption");
3739                 goto failed_mount_wq;
3740         }
3741
3742         if (DUMMY_ENCRYPTION_ENABLED(sbi) &&
3743             !(sb->s_flags & MS_RDONLY) &&
3744             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT)) {
3745                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT);
3746                 ext4_commit_super(sb, 1);
3747         }
3748
3749         /*
3750          * Get the # of file system overhead blocks from the
3751          * superblock if present.
3752          */
3753         if (es->s_overhead_clusters)
3754                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
3755         else {
3756                 err = ext4_calculate_overhead(sb);
3757                 if (err)
3758                         goto failed_mount_wq;
3759         }
3760
3761         /*
3762          * The maximum number of concurrent works can be high and
3763          * concurrency isn't really necessary.  Limit it to 1.
3764          */
3765         EXT4_SB(sb)->rsv_conversion_wq =
3766                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
3767         if (!EXT4_SB(sb)->rsv_conversion_wq) {
3768                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
3769                 ret = -ENOMEM;
3770                 goto failed_mount4;
3771         }
3772
3773         /*
3774          * The jbd2_journal_load will have done any necessary log recovery,
3775          * so we can safely mount the rest of the filesystem now.
3776          */
3777
3778         root = ext4_iget(sb, EXT4_ROOT_INO);
3779         if (IS_ERR(root)) {
3780                 ext4_msg(sb, KERN_ERR, "get root inode failed");
3781                 ret = PTR_ERR(root);
3782                 root = NULL;
3783                 goto failed_mount4;
3784         }
3785         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
3786                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
3787                 iput(root);
3788                 goto failed_mount4;
3789         }
3790         sb->s_root = d_make_root(root);
3791         if (!sb->s_root) {
3792                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
3793                 ret = -ENOMEM;
3794                 goto failed_mount4;
3795         }
3796
3797         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
3798                 sb->s_flags |= MS_RDONLY;
3799
3800         /* determine the minimum size of new large inodes, if present */
3801         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3802                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3803                                                      EXT4_GOOD_OLD_INODE_SIZE;
3804                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3805                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
3806                         if (sbi->s_want_extra_isize <
3807                             le16_to_cpu(es->s_want_extra_isize))
3808                                 sbi->s_want_extra_isize =
3809                                         le16_to_cpu(es->s_want_extra_isize);
3810                         if (sbi->s_want_extra_isize <
3811                             le16_to_cpu(es->s_min_extra_isize))
3812                                 sbi->s_want_extra_isize =
3813                                         le16_to_cpu(es->s_min_extra_isize);
3814                 }
3815         }
3816         /* Check if enough inode space is available */
3817         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3818                                                         sbi->s_inode_size) {
3819                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3820                                                        EXT4_GOOD_OLD_INODE_SIZE;
3821                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
3822                          "available");
3823         }
3824
3825         ext4_set_resv_clusters(sb);
3826
3827         err = ext4_setup_system_zone(sb);
3828         if (err) {
3829                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3830                          "zone (%d)", err);
3831                 goto failed_mount4a;
3832         }
3833
3834         ext4_ext_init(sb);
3835         err = ext4_mb_init(sb);
3836         if (err) {
3837                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
3838                          err);
3839                 goto failed_mount5;
3840         }
3841
3842         block = ext4_count_free_clusters(sb);
3843         ext4_free_blocks_count_set(sbi->s_es,
3844                                    EXT4_C2B(sbi, block));
3845         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
3846                                   GFP_KERNEL);
3847         if (!err) {
3848                 unsigned long freei = ext4_count_free_inodes(sb);
3849                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
3850                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
3851                                           GFP_KERNEL);
3852         }
3853         if (!err)
3854                 err = percpu_counter_init(&sbi->s_dirs_counter,
3855                                           ext4_count_dirs(sb), GFP_KERNEL);
3856         if (!err)
3857                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
3858                                           GFP_KERNEL);
3859         if (err) {
3860                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3861                 goto failed_mount6;
3862         }
3863
3864         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3865                 if (!ext4_fill_flex_info(sb)) {
3866                         ext4_msg(sb, KERN_ERR,
3867                                "unable to initialize "
3868                                "flex_bg meta info!");
3869                         goto failed_mount6;
3870                 }
3871
3872         err = ext4_register_li_request(sb, first_not_zeroed);
3873         if (err)
3874                 goto failed_mount6;
3875
3876         err = ext4_register_sysfs(sb);
3877         if (err)
3878                 goto failed_mount7;
3879
3880 #ifdef CONFIG_QUOTA
3881         /* Enable quota usage during mount. */
3882         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
3883             !(sb->s_flags & MS_RDONLY)) {
3884                 err = ext4_enable_quotas(sb);
3885                 if (err)
3886                         goto failed_mount8;
3887         }
3888 #endif  /* CONFIG_QUOTA */
3889
3890         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3891         ext4_orphan_cleanup(sb, es);
3892         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3893         if (needs_recovery) {
3894                 ext4_msg(sb, KERN_INFO, "recovery complete");
3895                 ext4_mark_recovery_complete(sb, es);
3896         }
3897         if (EXT4_SB(sb)->s_journal) {
3898                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3899                         descr = " journalled data mode";
3900                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3901                         descr = " ordered data mode";
3902                 else
3903                         descr = " writeback data mode";
3904         } else
3905                 descr = "out journal";
3906
3907         if (test_opt(sb, DISCARD)) {
3908                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
3909                 if (!blk_queue_discard(q))
3910                         ext4_msg(sb, KERN_WARNING,
3911                                  "mounting with \"discard\" option, but "
3912                                  "the device does not support discard");
3913         }
3914
3915         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
3916                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
3917                          "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
3918                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
3919
3920         if (es->s_error_count)
3921                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
3922
3923         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
3924         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
3925         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
3926         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
3927
3928         kfree(orig_data);
3929         return 0;
3930
3931 cantfind_ext4:
3932         if (!silent)
3933                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3934         goto failed_mount;
3935
3936 #ifdef CONFIG_QUOTA
3937 failed_mount8:
3938         ext4_unregister_sysfs(sb);
3939 #endif
3940 failed_mount7:
3941         ext4_unregister_li_request(sb);
3942 failed_mount6:
3943         ext4_mb_release(sb);
3944         if (sbi->s_flex_groups)
3945                 kvfree(sbi->s_flex_groups);
3946         percpu_counter_destroy(&sbi->s_freeclusters_counter);
3947         percpu_counter_destroy(&sbi->s_freeinodes_counter);
3948         percpu_counter_destroy(&sbi->s_dirs_counter);
3949         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
3950 failed_mount5:
3951         ext4_ext_release(sb);
3952         ext4_release_system_zone(sb);
3953 failed_mount4a:
3954         dput(sb->s_root);
3955         sb->s_root = NULL;
3956 failed_mount4:
3957         ext4_msg(sb, KERN_ERR, "mount failed");
3958         if (EXT4_SB(sb)->rsv_conversion_wq)
3959                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
3960 failed_mount_wq:
3961         if (sbi->s_journal) {
3962                 jbd2_journal_destroy(sbi->s_journal);
3963                 sbi->s_journal = NULL;
3964         }
3965 failed_mount3a:
3966         ext4_es_unregister_shrinker(sbi);
3967 failed_mount3:
3968         del_timer_sync(&sbi->s_err_report);
3969         if (sbi->s_mmp_tsk)
3970                 kthread_stop(sbi->s_mmp_tsk);
3971 failed_mount2:
3972         for (i = 0; i < db_count; i++)
3973                 brelse(sbi->s_group_desc[i]);
3974         kvfree(sbi->s_group_desc);
3975 failed_mount:
3976         if (sbi->s_chksum_driver)
3977                 crypto_free_shash(sbi->s_chksum_driver);
3978 #ifdef CONFIG_QUOTA
3979         for (i = 0; i < EXT4_MAXQUOTAS; i++)
3980                 kfree(sbi->s_qf_names[i]);
3981 #endif
3982         ext4_blkdev_remove(sbi);
3983         brelse(bh);
3984 out_fail:
3985         sb->s_fs_info = NULL;
3986         kfree(sbi->s_blockgroup_lock);
3987         kfree(sbi);
3988 out_free_orig:
3989         kfree(orig_data);
3990         return err ? err : ret;
3991 }
3992
3993 /*
3994  * Setup any per-fs journal parameters now.  We'll do this both on
3995  * initial mount, once the journal has been initialised but before we've
3996  * done any recovery; and again on any subsequent remount.
3997  */
3998 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
3999 {
4000         struct ext4_sb_info *sbi = EXT4_SB(sb);
4001
4002         journal->j_commit_interval = sbi->s_commit_interval;
4003         journal->j_min_batch_time = sbi->s_min_batch_time;
4004         journal->j_max_batch_time = sbi->s_max_batch_time;
4005
4006         write_lock(&journal->j_state_lock);
4007         if (test_opt(sb, BARRIER))
4008                 journal->j_flags |= JBD2_BARRIER;
4009         else
4010                 journal->j_flags &= ~JBD2_BARRIER;
4011         if (test_opt(sb, DATA_ERR_ABORT))
4012                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4013         else
4014                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4015         write_unlock(&journal->j_state_lock);
4016 }
4017
4018 static journal_t *ext4_get_journal(struct super_block *sb,
4019                                    unsigned int journal_inum)
4020 {
4021         struct inode *journal_inode;
4022         journal_t *journal;
4023
4024         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4025
4026         /* First, test for the existence of a valid inode on disk.  Bad
4027          * things happen if we iget() an unused inode, as the subsequent
4028          * iput() will try to delete it. */
4029
4030         journal_inode = ext4_iget(sb, journal_inum);
4031         if (IS_ERR(journal_inode)) {
4032                 ext4_msg(sb, KERN_ERR, "no journal found");
4033                 return NULL;
4034         }
4035         if (!journal_inode->i_nlink) {
4036                 make_bad_inode(journal_inode);
4037                 iput(journal_inode);
4038                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4039                 return NULL;
4040         }
4041
4042         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4043                   journal_inode, journal_inode->i_size);
4044         if (!S_ISREG(journal_inode->i_mode)) {
4045                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4046                 iput(journal_inode);
4047                 return NULL;
4048         }
4049
4050         journal = jbd2_journal_init_inode(journal_inode);
4051         if (!journal) {
4052                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4053                 iput(journal_inode);
4054                 return NULL;
4055         }
4056         journal->j_private = sb;
4057         ext4_init_journal_params(sb, journal);
4058         return journal;
4059 }
4060
4061 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4062                                        dev_t j_dev)
4063 {
4064         struct buffer_head *bh;
4065         journal_t *journal;
4066         ext4_fsblk_t start;
4067         ext4_fsblk_t len;
4068         int hblock, blocksize;
4069         ext4_fsblk_t sb_block;
4070         unsigned long offset;
4071         struct ext4_super_block *es;
4072         struct block_device *bdev;
4073
4074         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4075
4076         bdev = ext4_blkdev_get(j_dev, sb);
4077         if (bdev == NULL)
4078                 return NULL;
4079
4080         blocksize = sb->s_blocksize;
4081         hblock = bdev_logical_block_size(bdev);
4082         if (blocksize < hblock) {
4083                 ext4_msg(sb, KERN_ERR,
4084                         "blocksize too small for journal device");
4085                 goto out_bdev;
4086         }
4087
4088         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4089         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4090         set_blocksize(bdev, blocksize);
4091         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4092                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4093                        "external journal");
4094                 goto out_bdev;
4095         }
4096
4097         es = (struct ext4_super_block *) (bh->b_data + offset);
4098         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4099             !(le32_to_cpu(es->s_feature_incompat) &
4100               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4101                 ext4_msg(sb, KERN_ERR, "external journal has "
4102                                         "bad superblock");
4103                 brelse(bh);
4104                 goto out_bdev;
4105         }
4106
4107         if ((le32_to_cpu(es->s_feature_ro_compat) &
4108              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4109             es->s_checksum != ext4_superblock_csum(sb, es)) {
4110                 ext4_msg(sb, KERN_ERR, "external journal has "
4111                                        "corrupt superblock");
4112                 brelse(bh);
4113                 goto out_bdev;
4114         }
4115
4116         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4117                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4118                 brelse(bh);
4119                 goto out_bdev;
4120         }
4121
4122         len = ext4_blocks_count(es);
4123         start = sb_block + 1;
4124         brelse(bh);     /* we're done with the superblock */
4125
4126         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4127                                         start, len, blocksize);
4128         if (!journal) {
4129                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4130                 goto out_bdev;
4131         }
4132         journal->j_private = sb;
4133         ll_rw_block(READ | REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4134         wait_on_buffer(journal->j_sb_buffer);
4135         if (!buffer_uptodate(journal->j_sb_buffer)) {
4136                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4137                 goto out_journal;
4138         }
4139         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4140                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4141                                         "user (unsupported) - %d",
4142                         be32_to_cpu(journal->j_superblock->s_nr_users));
4143                 goto out_journal;
4144         }
4145         EXT4_SB(sb)->journal_bdev = bdev;
4146         ext4_init_journal_params(sb, journal);
4147         return journal;
4148
4149 out_journal:
4150         jbd2_journal_destroy(journal);
4151 out_bdev:
4152         ext4_blkdev_put(bdev);
4153         return NULL;
4154 }
4155
4156 static int ext4_load_journal(struct super_block *sb,
4157                              struct ext4_super_block *es,
4158                              unsigned long journal_devnum)
4159 {
4160         journal_t *journal;
4161         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4162         dev_t journal_dev;
4163         int err = 0;
4164         int really_read_only;
4165
4166         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4167
4168         if (journal_devnum &&
4169             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4170                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4171                         "numbers have changed");
4172                 journal_dev = new_decode_dev(journal_devnum);
4173         } else
4174                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4175
4176         really_read_only = bdev_read_only(sb->s_bdev);
4177
4178         /*
4179          * Are we loading a blank journal or performing recovery after a
4180          * crash?  For recovery, we need to check in advance whether we
4181          * can get read-write access to the device.
4182          */
4183         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4184                 if (sb->s_flags & MS_RDONLY) {
4185                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4186                                         "required on readonly filesystem");
4187                         if (really_read_only) {
4188                                 ext4_msg(sb, KERN_ERR, "write access "
4189                                         "unavailable, cannot proceed");
4190                                 return -EROFS;
4191                         }
4192                         ext4_msg(sb, KERN_INFO, "write access will "
4193                                "be enabled during recovery");
4194                 }
4195         }
4196
4197         if (journal_inum && journal_dev) {
4198                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4199                        "and inode journals!");
4200                 return -EINVAL;
4201         }
4202
4203         if (journal_inum) {
4204                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4205                         return -EINVAL;
4206         } else {
4207                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4208                         return -EINVAL;
4209         }
4210
4211         if (!(journal->j_flags & JBD2_BARRIER))
4212                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4213
4214         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4215                 err = jbd2_journal_wipe(journal, !really_read_only);
4216         if (!err) {
4217                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4218                 if (save)
4219                         memcpy(save, ((char *) es) +
4220                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4221                 err = jbd2_journal_load(journal);
4222                 if (save)
4223                         memcpy(((char *) es) + EXT4_S_ERR_START,
4224                                save, EXT4_S_ERR_LEN);
4225                 kfree(save);
4226         }
4227
4228         if (err) {
4229                 ext4_msg(sb, KERN_ERR, "error loading journal");
4230                 jbd2_journal_destroy(journal);
4231                 return err;
4232         }
4233
4234         EXT4_SB(sb)->s_journal = journal;
4235         ext4_clear_journal_err(sb, es);
4236
4237         if (!really_read_only && journal_devnum &&
4238             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4239                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4240
4241                 /* Make sure we flush the recovery flag to disk. */
4242                 ext4_commit_super(sb, 1);
4243         }
4244
4245         return 0;
4246 }
4247
4248 static int ext4_commit_super(struct super_block *sb, int sync)
4249 {
4250         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4251         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4252         int error = 0;
4253
4254         if (!sbh || block_device_ejected(sb))
4255                 return error;
4256         if (buffer_write_io_error(sbh)) {
4257                 /*
4258                  * Oh, dear.  A previous attempt to write the
4259                  * superblock failed.  This could happen because the
4260                  * USB device was yanked out.  Or it could happen to
4261                  * be a transient write error and maybe the block will
4262                  * be remapped.  Nothing we can do but to retry the
4263                  * write and hope for the best.
4264                  */
4265                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4266                        "superblock detected");
4267                 clear_buffer_write_io_error(sbh);
4268                 set_buffer_uptodate(sbh);
4269         }
4270         /*
4271          * If the file system is mounted read-only, don't update the
4272          * superblock write time.  This avoids updating the superblock
4273          * write time when we are mounting the root file system
4274          * read/only but we need to replay the journal; at that point,
4275          * for people who are east of GMT and who make their clock
4276          * tick in localtime for Windows bug-for-bug compatibility,
4277          * the clock is set in the future, and this will cause e2fsck
4278          * to complain and force a full file system check.
4279          */
4280         if (!(sb->s_flags & MS_RDONLY))
4281                 es->s_wtime = cpu_to_le32(get_seconds());
4282         if (sb->s_bdev->bd_part)
4283                 es->s_kbytes_written =
4284                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4285                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4286                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4287         else
4288                 es->s_kbytes_written =
4289                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4290         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4291                 ext4_free_blocks_count_set(es,
4292                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4293                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4294         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4295                 es->s_free_inodes_count =
4296                         cpu_to_le32(percpu_counter_sum_positive(
4297                                 &EXT4_SB(sb)->s_freeinodes_counter));
4298         BUFFER_TRACE(sbh, "marking dirty");
4299         ext4_superblock_csum_set(sb);
4300         mark_buffer_dirty(sbh);
4301         if (sync) {
4302                 error = __sync_dirty_buffer(sbh,
4303                         test_opt(sb, BARRIER) ? WRITE_FUA : WRITE_SYNC);
4304                 if (error)
4305                         return error;
4306
4307                 error = buffer_write_io_error(sbh);
4308                 if (error) {
4309                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4310                                "superblock");
4311                         clear_buffer_write_io_error(sbh);
4312                         set_buffer_uptodate(sbh);
4313                 }
4314         }
4315         return error;
4316 }
4317
4318 /*
4319  * Have we just finished recovery?  If so, and if we are mounting (or
4320  * remounting) the filesystem readonly, then we will end up with a
4321  * consistent fs on disk.  Record that fact.
4322  */
4323 static void ext4_mark_recovery_complete(struct super_block *sb,
4324                                         struct ext4_super_block *es)
4325 {
4326         journal_t *journal = EXT4_SB(sb)->s_journal;
4327
4328         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4329                 BUG_ON(journal != NULL);
4330                 return;
4331         }
4332         jbd2_journal_lock_updates(journal);
4333         if (jbd2_journal_flush(journal) < 0)
4334                 goto out;
4335
4336         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4337             sb->s_flags & MS_RDONLY) {
4338                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4339                 ext4_commit_super(sb, 1);
4340         }
4341
4342 out:
4343         jbd2_journal_unlock_updates(journal);
4344 }
4345
4346 /*
4347  * If we are mounting (or read-write remounting) a filesystem whose journal
4348  * has recorded an error from a previous lifetime, move that error to the
4349  * main filesystem now.
4350  */
4351 static void ext4_clear_journal_err(struct super_block *sb,
4352                                    struct ext4_super_block *es)
4353 {
4354         journal_t *journal;
4355         int j_errno;
4356         const char *errstr;
4357
4358         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4359
4360         journal = EXT4_SB(sb)->s_journal;
4361
4362         /*
4363          * Now check for any error status which may have been recorded in the
4364          * journal by a prior ext4_error() or ext4_abort()
4365          */
4366
4367         j_errno = jbd2_journal_errno(journal);
4368         if (j_errno) {
4369                 char nbuf[16];
4370
4371                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4372                 ext4_warning(sb, "Filesystem error recorded "
4373                              "from previous mount: %s", errstr);
4374                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4375
4376                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4377                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4378                 ext4_commit_super(sb, 1);
4379
4380                 jbd2_journal_clear_err(journal);
4381                 jbd2_journal_update_sb_errno(journal);
4382         }
4383 }
4384
4385 /*
4386  * Force the running and committing transactions to commit,
4387  * and wait on the commit.
4388  */
4389 int ext4_force_commit(struct super_block *sb)
4390 {
4391         journal_t *journal;
4392
4393         if (sb->s_flags & MS_RDONLY)
4394                 return 0;
4395
4396         journal = EXT4_SB(sb)->s_journal;
4397         return ext4_journal_force_commit(journal);
4398 }
4399
4400 static int ext4_sync_fs(struct super_block *sb, int wait)
4401 {
4402         int ret = 0;
4403         tid_t target;
4404         bool needs_barrier = false;
4405         struct ext4_sb_info *sbi = EXT4_SB(sb);
4406
4407         trace_ext4_sync_fs(sb, wait);
4408         flush_workqueue(sbi->rsv_conversion_wq);
4409         /*
4410          * Writeback quota in non-journalled quota case - journalled quota has
4411          * no dirty dquots
4412          */
4413         dquot_writeback_dquots(sb, -1);
4414         /*
4415          * Data writeback is possible w/o journal transaction, so barrier must
4416          * being sent at the end of the function. But we can skip it if
4417          * transaction_commit will do it for us.
4418          */
4419         if (sbi->s_journal) {
4420                 target = jbd2_get_latest_transaction(sbi->s_journal);
4421                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
4422                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
4423                         needs_barrier = true;
4424
4425                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4426                         if (wait)
4427                                 ret = jbd2_log_wait_commit(sbi->s_journal,
4428                                                            target);
4429                 }
4430         } else if (wait && test_opt(sb, BARRIER))
4431                 needs_barrier = true;
4432         if (needs_barrier) {
4433                 int err;
4434                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4435                 if (!ret)
4436                         ret = err;
4437         }
4438
4439         return ret;
4440 }
4441
4442 /*
4443  * LVM calls this function before a (read-only) snapshot is created.  This
4444  * gives us a chance to flush the journal completely and mark the fs clean.
4445  *
4446  * Note that only this function cannot bring a filesystem to be in a clean
4447  * state independently. It relies on upper layer to stop all data & metadata
4448  * modifications.
4449  */
4450 static int ext4_freeze(struct super_block *sb)
4451 {
4452         int error = 0;
4453         journal_t *journal;
4454
4455         if (sb->s_flags & MS_RDONLY)
4456                 return 0;
4457
4458         journal = EXT4_SB(sb)->s_journal;
4459
4460         if (journal) {
4461                 /* Now we set up the journal barrier. */
4462                 jbd2_journal_lock_updates(journal);
4463
4464                 /*
4465                  * Don't clear the needs_recovery flag if we failed to
4466                  * flush the journal.
4467                  */
4468                 error = jbd2_journal_flush(journal);
4469                 if (error < 0)
4470                         goto out;
4471
4472                 /* Journal blocked and flushed, clear needs_recovery flag. */
4473                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4474         }
4475
4476         error = ext4_commit_super(sb, 1);
4477 out:
4478         if (journal)
4479                 /* we rely on upper layer to stop further updates */
4480                 jbd2_journal_unlock_updates(journal);
4481         return error;
4482 }
4483
4484 /*
4485  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4486  * flag here, even though the filesystem is not technically dirty yet.
4487  */
4488 static int ext4_unfreeze(struct super_block *sb)
4489 {
4490         if (sb->s_flags & MS_RDONLY)
4491                 return 0;
4492
4493         if (EXT4_SB(sb)->s_journal) {
4494                 /* Reset the needs_recovery flag before the fs is unlocked. */
4495                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4496         }
4497
4498         ext4_commit_super(sb, 1);
4499         return 0;
4500 }
4501
4502 /*
4503  * Structure to save mount options for ext4_remount's benefit
4504  */
4505 struct ext4_mount_options {
4506         unsigned long s_mount_opt;
4507         unsigned long s_mount_opt2;
4508         kuid_t s_resuid;
4509         kgid_t s_resgid;
4510         unsigned long s_commit_interval;
4511         u32 s_min_batch_time, s_max_batch_time;
4512 #ifdef CONFIG_QUOTA
4513         int s_jquota_fmt;
4514         char *s_qf_names[EXT4_MAXQUOTAS];
4515 #endif
4516 };
4517
4518 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4519 {
4520         struct ext4_super_block *es;
4521         struct ext4_sb_info *sbi = EXT4_SB(sb);
4522         unsigned long old_sb_flags;
4523         struct ext4_mount_options old_opts;
4524         int enable_quota = 0;
4525         ext4_group_t g;
4526         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4527         int err = 0;
4528 #ifdef CONFIG_QUOTA
4529         int i, j;
4530 #endif
4531         char *orig_data = kstrdup(data, GFP_KERNEL);
4532
4533         /* Store the original options */
4534         old_sb_flags = sb->s_flags;
4535         old_opts.s_mount_opt = sbi->s_mount_opt;
4536         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4537         old_opts.s_resuid = sbi->s_resuid;
4538         old_opts.s_resgid = sbi->s_resgid;
4539         old_opts.s_commit_interval = sbi->s_commit_interval;
4540         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4541         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4542 #ifdef CONFIG_QUOTA
4543         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4544         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4545                 if (sbi->s_qf_names[i]) {
4546                         old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
4547                                                          GFP_KERNEL);
4548                         if (!old_opts.s_qf_names[i]) {
4549                                 for (j = 0; j < i; j++)
4550                                         kfree(old_opts.s_qf_names[j]);
4551                                 kfree(orig_data);
4552                                 return -ENOMEM;
4553                         }
4554                 } else
4555                         old_opts.s_qf_names[i] = NULL;
4556 #endif
4557         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4558                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4559
4560         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4561                 err = -EINVAL;
4562                 goto restore_opts;
4563         }
4564
4565         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
4566             test_opt(sb, JOURNAL_CHECKSUM)) {
4567                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
4568                          "during remount not supported; ignoring");
4569                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
4570         }
4571
4572         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4573                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4574                         ext4_msg(sb, KERN_ERR, "can't mount with "
4575                                  "both data=journal and delalloc");
4576                         err = -EINVAL;
4577                         goto restore_opts;
4578                 }
4579                 if (test_opt(sb, DIOREAD_NOLOCK)) {
4580                         ext4_msg(sb, KERN_ERR, "can't mount with "
4581                                  "both data=journal and dioread_nolock");
4582                         err = -EINVAL;
4583                         goto restore_opts;
4584                 }
4585                 if (test_opt(sb, DAX)) {
4586                         ext4_msg(sb, KERN_ERR, "can't mount with "
4587                                  "both data=journal and dax");
4588                         err = -EINVAL;
4589                         goto restore_opts;
4590                 }
4591         }
4592
4593         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
4594                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
4595                         "dax flag with busy inodes while remounting");
4596                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
4597         }
4598
4599         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4600                 ext4_abort(sb, "Abort forced by user");
4601
4602         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4603                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4604
4605         es = sbi->s_es;
4606
4607         if (sbi->s_journal) {
4608                 ext4_init_journal_params(sb, sbi->s_journal);
4609                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4610         }
4611
4612         if (*flags & MS_LAZYTIME)
4613                 sb->s_flags |= MS_LAZYTIME;
4614
4615         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4616                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4617                         err = -EROFS;
4618                         goto restore_opts;
4619                 }
4620
4621                 if (*flags & MS_RDONLY) {
4622                         err = sync_filesystem(sb);
4623                         if (err < 0)
4624                                 goto restore_opts;
4625                         err = dquot_suspend(sb, -1);
4626                         if (err < 0)
4627                                 goto restore_opts;
4628
4629                         /*
4630                          * First of all, the unconditional stuff we have to do
4631                          * to disable replay of the journal when we next remount
4632                          */
4633                         sb->s_flags |= MS_RDONLY;
4634
4635                         /*
4636                          * OK, test if we are remounting a valid rw partition
4637                          * readonly, and if so set the rdonly flag and then
4638                          * mark the partition as valid again.
4639                          */
4640                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
4641                             (sbi->s_mount_state & EXT4_VALID_FS))
4642                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
4643
4644                         if (sbi->s_journal)
4645                                 ext4_mark_recovery_complete(sb, es);
4646                 } else {
4647                         /* Make sure we can mount this feature set readwrite */
4648                         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
4649                                         EXT4_FEATURE_RO_COMPAT_READONLY) ||
4650                             !ext4_feature_set_ok(sb, 0)) {
4651                                 err = -EROFS;
4652                                 goto restore_opts;
4653                         }
4654                         /*
4655                          * Make sure the group descriptor checksums
4656                          * are sane.  If they aren't, refuse to remount r/w.
4657                          */
4658                         for (g = 0; g < sbi->s_groups_count; g++) {
4659                                 struct ext4_group_desc *gdp =
4660                                         ext4_get_group_desc(sb, g, NULL);
4661
4662                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
4663                                         ext4_msg(sb, KERN_ERR,
4664                "ext4_remount: Checksum for group %u failed (%u!=%u)",
4665                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
4666                                                le16_to_cpu(gdp->bg_checksum));
4667                                         err = -EINVAL;
4668                                         goto restore_opts;
4669                                 }
4670                         }
4671
4672                         /*
4673                          * If we have an unprocessed orphan list hanging
4674                          * around from a previously readonly bdev mount,
4675                          * require a full umount/remount for now.
4676                          */
4677                         if (es->s_last_orphan) {
4678                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
4679                                        "remount RDWR because of unprocessed "
4680                                        "orphan inode list.  Please "
4681                                        "umount/remount instead");
4682                                 err = -EINVAL;
4683                                 goto restore_opts;
4684                         }
4685
4686                         /*
4687                          * Mounting a RDONLY partition read-write, so reread
4688                          * and store the current valid flag.  (It may have
4689                          * been changed by e2fsck since we originally mounted
4690                          * the partition.)
4691                          */
4692                         if (sbi->s_journal)
4693                                 ext4_clear_journal_err(sb, es);
4694                         sbi->s_mount_state = le16_to_cpu(es->s_state);
4695                         if (!ext4_setup_super(sb, es, 0))
4696                                 sb->s_flags &= ~MS_RDONLY;
4697                         if (EXT4_HAS_INCOMPAT_FEATURE(sb,
4698                                                      EXT4_FEATURE_INCOMPAT_MMP))
4699                                 if (ext4_multi_mount_protect(sb,
4700                                                 le64_to_cpu(es->s_mmp_block))) {
4701                                         err = -EROFS;
4702                                         goto restore_opts;
4703                                 }
4704                         enable_quota = 1;
4705                 }
4706         }
4707
4708         /*
4709          * Reinitialize lazy itable initialization thread based on
4710          * current settings
4711          */
4712         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
4713                 ext4_unregister_li_request(sb);
4714         else {
4715                 ext4_group_t first_not_zeroed;
4716                 first_not_zeroed = ext4_has_uninit_itable(sb);
4717                 ext4_register_li_request(sb, first_not_zeroed);
4718         }
4719
4720         ext4_setup_system_zone(sb);
4721         if (sbi->s_journal == NULL && !(old_sb_flags & MS_RDONLY))
4722                 ext4_commit_super(sb, 1);
4723
4724 #ifdef CONFIG_QUOTA
4725         /* Release old quota file names */
4726         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4727                 kfree(old_opts.s_qf_names[i]);
4728         if (enable_quota) {
4729                 if (sb_any_quota_suspended(sb))
4730                         dquot_resume(sb, -1);
4731                 else if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
4732                                         EXT4_FEATURE_RO_COMPAT_QUOTA)) {
4733                         err = ext4_enable_quotas(sb);
4734                         if (err)
4735                                 goto restore_opts;
4736                 }
4737         }
4738 #endif
4739
4740         *flags = (*flags & ~MS_LAZYTIME) | (sb->s_flags & MS_LAZYTIME);
4741         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
4742         kfree(orig_data);
4743         return 0;
4744
4745 restore_opts:
4746         sb->s_flags = old_sb_flags;
4747         sbi->s_mount_opt = old_opts.s_mount_opt;
4748         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
4749         sbi->s_resuid = old_opts.s_resuid;
4750         sbi->s_resgid = old_opts.s_resgid;
4751         sbi->s_commit_interval = old_opts.s_commit_interval;
4752         sbi->s_min_batch_time = old_opts.s_min_batch_time;
4753         sbi->s_max_batch_time = old_opts.s_max_batch_time;
4754 #ifdef CONFIG_QUOTA
4755         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
4756         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
4757                 kfree(sbi->s_qf_names[i]);
4758                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
4759         }
4760 #endif
4761         kfree(orig_data);
4762         return err;
4763 }
4764
4765 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
4766 {
4767         struct super_block *sb = dentry->d_sb;
4768         struct ext4_sb_info *sbi = EXT4_SB(sb);
4769         struct ext4_super_block *es = sbi->s_es;
4770         ext4_fsblk_t overhead = 0, resv_blocks;
4771         u64 fsid;
4772         s64 bfree;
4773         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
4774
4775         if (!test_opt(sb, MINIX_DF))
4776                 overhead = sbi->s_overhead;
4777
4778         buf->f_type = EXT4_SUPER_MAGIC;
4779         buf->f_bsize = sb->s_blocksize;
4780         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
4781         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
4782                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
4783         /* prevent underflow in case that few free space is available */
4784         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
4785         buf->f_bavail = buf->f_bfree -
4786                         (ext4_r_blocks_count(es) + resv_blocks);
4787         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
4788                 buf->f_bavail = 0;
4789         buf->f_files = le32_to_cpu(es->s_inodes_count);
4790         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
4791         buf->f_namelen = EXT4_NAME_LEN;
4792         fsid = le64_to_cpup((void *)es->s_uuid) ^
4793                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
4794         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
4795         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
4796
4797         return 0;
4798 }
4799
4800 /* Helper function for writing quotas on sync - we need to start transaction
4801  * before quota file is locked for write. Otherwise the are possible deadlocks:
4802  * Process 1                         Process 2
4803  * ext4_create()                     quota_sync()
4804  *   jbd2_journal_start()                  write_dquot()
4805  *   dquot_initialize()                         down(dqio_mutex)
4806  *     down(dqio_mutex)                    jbd2_journal_start()
4807  *
4808  */
4809
4810 #ifdef CONFIG_QUOTA
4811
4812 static inline struct inode *dquot_to_inode(struct dquot *dquot)
4813 {
4814         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
4815 }
4816
4817 static int ext4_write_dquot(struct dquot *dquot)
4818 {
4819         int ret, err;
4820         handle_t *handle;
4821         struct inode *inode;
4822
4823         inode = dquot_to_inode(dquot);
4824         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
4825                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
4826         if (IS_ERR(handle))
4827                 return PTR_ERR(handle);
4828         ret = dquot_commit(dquot);
4829         err = ext4_journal_stop(handle);
4830         if (!ret)
4831                 ret = err;
4832         return ret;
4833 }
4834
4835 static int ext4_acquire_dquot(struct dquot *dquot)
4836 {
4837         int ret, err;
4838         handle_t *handle;
4839
4840         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
4841                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
4842         if (IS_ERR(handle))
4843                 return PTR_ERR(handle);
4844         ret = dquot_acquire(dquot);
4845         err = ext4_journal_stop(handle);
4846         if (!ret)
4847                 ret = err;
4848         return ret;
4849 }
4850
4851 static int ext4_release_dquot(struct dquot *dquot)
4852 {
4853         int ret, err;
4854         handle_t *handle;
4855
4856         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
4857                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
4858         if (IS_ERR(handle)) {
4859                 /* Release dquot anyway to avoid endless cycle in dqput() */
4860                 dquot_release(dquot);
4861                 return PTR_ERR(handle);
4862         }
4863         ret = dquot_release(dquot);
4864         err = ext4_journal_stop(handle);
4865         if (!ret)
4866                 ret = err;
4867         return ret;
4868 }
4869
4870 static int ext4_mark_dquot_dirty(struct dquot *dquot)
4871 {
4872         struct super_block *sb = dquot->dq_sb;
4873         struct ext4_sb_info *sbi = EXT4_SB(sb);
4874
4875         /* Are we journaling quotas? */
4876         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) ||
4877             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
4878                 dquot_mark_dquot_dirty(dquot);
4879                 return ext4_write_dquot(dquot);
4880         } else {
4881                 return dquot_mark_dquot_dirty(dquot);
4882         }
4883 }
4884
4885 static int ext4_write_info(struct super_block *sb, int type)
4886 {
4887         int ret, err;
4888         handle_t *handle;
4889
4890         /* Data block + inode block */
4891         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
4892         if (IS_ERR(handle))
4893                 return PTR_ERR(handle);
4894         ret = dquot_commit_info(sb, type);
4895         err = ext4_journal_stop(handle);
4896         if (!ret)
4897                 ret = err;
4898         return ret;
4899 }
4900
4901 /*
4902  * Turn on quotas during mount time - we need to find
4903  * the quota file and such...
4904  */
4905 static int ext4_quota_on_mount(struct super_block *sb, int type)
4906 {
4907         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
4908                                         EXT4_SB(sb)->s_jquota_fmt, type);
4909 }
4910
4911 /*
4912  * Standard function to be called on quota_on
4913  */
4914 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
4915                          struct path *path)
4916 {
4917         int err;
4918
4919         if (!test_opt(sb, QUOTA))
4920                 return -EINVAL;
4921
4922         /* Quotafile not on the same filesystem? */
4923         if (path->dentry->d_sb != sb)
4924                 return -EXDEV;
4925         /* Journaling quota? */
4926         if (EXT4_SB(sb)->s_qf_names[type]) {
4927                 /* Quotafile not in fs root? */
4928                 if (path->dentry->d_parent != sb->s_root)
4929                         ext4_msg(sb, KERN_WARNING,
4930                                 "Quota file not on filesystem root. "
4931                                 "Journaled quota will not work");
4932         }
4933
4934         /*
4935          * When we journal data on quota file, we have to flush journal to see
4936          * all updates to the file when we bypass pagecache...
4937          */
4938         if (EXT4_SB(sb)->s_journal &&
4939             ext4_should_journal_data(d_inode(path->dentry))) {
4940                 /*
4941                  * We don't need to lock updates but journal_flush() could
4942                  * otherwise be livelocked...
4943                  */
4944                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
4945                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
4946                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
4947                 if (err)
4948                         return err;
4949         }
4950
4951         return dquot_quota_on(sb, type, format_id, path);
4952 }
4953
4954 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
4955                              unsigned int flags)
4956 {
4957         int err;
4958         struct inode *qf_inode;
4959         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
4960                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
4961                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
4962         };
4963
4964         BUG_ON(!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA));
4965
4966         if (!qf_inums[type])
4967                 return -EPERM;
4968
4969         qf_inode = ext4_iget(sb, qf_inums[type]);
4970         if (IS_ERR(qf_inode)) {
4971                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
4972                 return PTR_ERR(qf_inode);
4973         }
4974
4975         /* Don't account quota for quota files to avoid recursion */
4976         qf_inode->i_flags |= S_NOQUOTA;
4977         err = dquot_enable(qf_inode, type, format_id, flags);
4978         iput(qf_inode);
4979
4980         return err;
4981 }
4982
4983 /* Enable usage tracking for all quota types. */
4984 static int ext4_enable_quotas(struct super_block *sb)
4985 {
4986         int type, err = 0;
4987         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
4988                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
4989                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
4990         };
4991
4992         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
4993         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
4994                 if (qf_inums[type]) {
4995                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
4996                                                 DQUOT_USAGE_ENABLED);
4997                         if (err) {
4998                                 ext4_warning(sb,
4999                                         "Failed to enable quota tracking "
5000                                         "(type=%d, err=%d). Please run "
5001                                         "e2fsck to fix.", type, err);
5002                                 return err;
5003                         }
5004                 }
5005         }
5006         return 0;
5007 }
5008
5009 static int ext4_quota_off(struct super_block *sb, int type)
5010 {
5011         struct inode *inode = sb_dqopt(sb)->files[type];
5012         handle_t *handle;
5013
5014         /* Force all delayed allocation blocks to be allocated.
5015          * Caller already holds s_umount sem */
5016         if (test_opt(sb, DELALLOC))
5017                 sync_filesystem(sb);
5018
5019         if (!inode)
5020                 goto out;
5021
5022         /* Update modification times of quota files when userspace can
5023          * start looking at them */
5024         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5025         if (IS_ERR(handle))
5026                 goto out;
5027         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
5028         ext4_mark_inode_dirty(handle, inode);
5029         ext4_journal_stop(handle);
5030
5031 out:
5032         return dquot_quota_off(sb, type);
5033 }
5034
5035 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5036  * acquiring the locks... As quota files are never truncated and quota code
5037  * itself serializes the operations (and no one else should touch the files)
5038  * we don't have to be afraid of races */
5039 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5040                                size_t len, loff_t off)
5041 {
5042         struct inode *inode = sb_dqopt(sb)->files[type];
5043         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5044         int offset = off & (sb->s_blocksize - 1);
5045         int tocopy;
5046         size_t toread;
5047         struct buffer_head *bh;
5048         loff_t i_size = i_size_read(inode);
5049
5050         if (off > i_size)
5051                 return 0;
5052         if (off+len > i_size)
5053                 len = i_size-off;
5054         toread = len;
5055         while (toread > 0) {
5056                 tocopy = sb->s_blocksize - offset < toread ?
5057                                 sb->s_blocksize - offset : toread;
5058                 bh = ext4_bread(NULL, inode, blk, 0);
5059                 if (IS_ERR(bh))
5060                         return PTR_ERR(bh);
5061                 if (!bh)        /* A hole? */
5062                         memset(data, 0, tocopy);
5063                 else
5064                         memcpy(data, bh->b_data+offset, tocopy);
5065                 brelse(bh);
5066                 offset = 0;
5067                 toread -= tocopy;
5068                 data += tocopy;
5069                 blk++;
5070         }
5071         return len;
5072 }
5073
5074 /* Write to quotafile (we know the transaction is already started and has
5075  * enough credits) */
5076 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5077                                 const char *data, size_t len, loff_t off)
5078 {
5079         struct inode *inode = sb_dqopt(sb)->files[type];
5080         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5081         int err, offset = off & (sb->s_blocksize - 1);
5082         int retries = 0;
5083         struct buffer_head *bh;
5084         handle_t *handle = journal_current_handle();
5085
5086         if (EXT4_SB(sb)->s_journal && !handle) {
5087                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5088                         " cancelled because transaction is not started",
5089                         (unsigned long long)off, (unsigned long long)len);
5090                 return -EIO;
5091         }
5092         /*
5093          * Since we account only one data block in transaction credits,
5094          * then it is impossible to cross a block boundary.
5095          */
5096         if (sb->s_blocksize - offset < len) {
5097                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5098                         " cancelled because not block aligned",
5099                         (unsigned long long)off, (unsigned long long)len);
5100                 return -EIO;
5101         }
5102
5103         do {
5104                 bh = ext4_bread(handle, inode, blk,
5105                                 EXT4_GET_BLOCKS_CREATE |
5106                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5107         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5108                  ext4_should_retry_alloc(inode->i_sb, &retries));
5109         if (IS_ERR(bh))
5110                 return PTR_ERR(bh);
5111         if (!bh)
5112                 goto out;
5113         BUFFER_TRACE(bh, "get write access");
5114         err = ext4_journal_get_write_access(handle, bh);
5115         if (err) {
5116                 brelse(bh);
5117                 return err;
5118         }
5119         lock_buffer(bh);
5120         memcpy(bh->b_data+offset, data, len);
5121         flush_dcache_page(bh->b_page);
5122         unlock_buffer(bh);
5123         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5124         brelse(bh);
5125 out:
5126         if (inode->i_size < off + len) {
5127                 i_size_write(inode, off + len);
5128                 EXT4_I(inode)->i_disksize = inode->i_size;
5129                 ext4_mark_inode_dirty(handle, inode);
5130         }
5131         return len;
5132 }
5133
5134 #endif
5135
5136 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5137                        const char *dev_name, void *data)
5138 {
5139         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5140 }
5141
5142 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
5143 static inline void register_as_ext2(void)
5144 {
5145         int err = register_filesystem(&ext2_fs_type);
5146         if (err)
5147                 printk(KERN_WARNING
5148                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5149 }
5150
5151 static inline void unregister_as_ext2(void)
5152 {
5153         unregister_filesystem(&ext2_fs_type);
5154 }
5155
5156 static inline int ext2_feature_set_ok(struct super_block *sb)
5157 {
5158         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
5159                 return 0;
5160         if (sb->s_flags & MS_RDONLY)
5161                 return 1;
5162         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
5163                 return 0;
5164         return 1;
5165 }
5166 #else
5167 static inline void register_as_ext2(void) { }
5168 static inline void unregister_as_ext2(void) { }
5169 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5170 #endif
5171
5172 static inline void register_as_ext3(void)
5173 {
5174         int err = register_filesystem(&ext3_fs_type);
5175         if (err)
5176                 printk(KERN_WARNING
5177                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5178 }
5179
5180 static inline void unregister_as_ext3(void)
5181 {
5182         unregister_filesystem(&ext3_fs_type);
5183 }
5184
5185 static inline int ext3_feature_set_ok(struct super_block *sb)
5186 {
5187         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
5188                 return 0;
5189         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
5190                 return 0;
5191         if (sb->s_flags & MS_RDONLY)
5192                 return 1;
5193         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
5194                 return 0;
5195         return 1;
5196 }
5197
5198 static struct file_system_type ext4_fs_type = {
5199         .owner          = THIS_MODULE,
5200         .name           = "ext4",
5201         .mount          = ext4_mount,
5202         .kill_sb        = kill_block_super,
5203         .fs_flags       = FS_REQUIRES_DEV,
5204 };
5205 MODULE_ALIAS_FS("ext4");
5206
5207 /* Shared across all ext4 file systems */
5208 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5209 struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5210
5211 static int __init ext4_init_fs(void)
5212 {
5213         int i, err;
5214
5215         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
5216         ext4_li_info = NULL;
5217         mutex_init(&ext4_li_mtx);
5218
5219         /* Build-time check for flags consistency */
5220         ext4_check_flag_values();
5221
5222         for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5223                 mutex_init(&ext4__aio_mutex[i]);
5224                 init_waitqueue_head(&ext4__ioend_wq[i]);
5225         }
5226
5227         err = ext4_init_es();
5228         if (err)
5229                 return err;
5230
5231         err = ext4_init_pageio();
5232         if (err)
5233                 goto out5;
5234
5235         err = ext4_init_system_zone();
5236         if (err)
5237                 goto out4;
5238
5239         err = ext4_init_sysfs();
5240         if (err)
5241                 goto out3;
5242
5243         err = ext4_init_mballoc();
5244         if (err)
5245                 goto out2;
5246         else
5247                 ext4_mballoc_ready = 1;
5248         err = init_inodecache();
5249         if (err)
5250                 goto out1;
5251         register_as_ext3();
5252         register_as_ext2();
5253         err = register_filesystem(&ext4_fs_type);
5254         if (err)
5255                 goto out;
5256
5257         return 0;
5258 out:
5259         unregister_as_ext2();
5260         unregister_as_ext3();
5261         destroy_inodecache();
5262 out1:
5263         ext4_mballoc_ready = 0;
5264         ext4_exit_mballoc();
5265 out2:
5266         ext4_exit_sysfs();
5267 out3:
5268         ext4_exit_system_zone();
5269 out4:
5270         ext4_exit_pageio();
5271 out5:
5272         ext4_exit_es();
5273
5274         return err;
5275 }
5276
5277 static void __exit ext4_exit_fs(void)
5278 {
5279         ext4_exit_crypto();
5280         ext4_destroy_lazyinit_thread();
5281         unregister_as_ext2();
5282         unregister_as_ext3();
5283         unregister_filesystem(&ext4_fs_type);
5284         destroy_inodecache();
5285         ext4_exit_mballoc();
5286         ext4_exit_sysfs();
5287         ext4_exit_system_zone();
5288         ext4_exit_pageio();
5289         ext4_exit_es();
5290 }
5291
5292 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5293 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5294 MODULE_LICENSE("GPL");
5295 module_init(ext4_init_fs)
5296 module_exit(ext4_exit_fs)