linux/fs/ext4/super.c
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   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/proc_fs.h>
  38#include <linux/ctype.h>
  39#include <linux/log2.h>
  40#include <linux/crc16.h>
  41#include <linux/cleancache.h>
  42#include <asm/uaccess.h>
  43
  44#include <linux/kthread.h>
  45#include <linux/freezer.h>
  46
  47#include "ext4.h"
  48#include "ext4_extents.h"       /* Needed for trace points definition */
  49#include "ext4_jbd2.h"
  50#include "xattr.h"
  51#include "acl.h"
  52#include "mballoc.h"
  53
  54#define CREATE_TRACE_POINTS
  55#include <trace/events/ext4.h>
  56
  57static struct proc_dir_entry *ext4_proc_root;
  58static struct kset *ext4_kset;
  59static struct ext4_lazy_init *ext4_li_info;
  60static struct mutex ext4_li_mtx;
  61static struct ext4_features *ext4_feat;
  62static int ext4_mballoc_ready;
  63
  64static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  65                             unsigned long journal_devnum);
  66static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  67static int ext4_commit_super(struct super_block *sb, int sync);
  68static void ext4_mark_recovery_complete(struct super_block *sb,
  69                                        struct ext4_super_block *es);
  70static void ext4_clear_journal_err(struct super_block *sb,
  71                                   struct ext4_super_block *es);
  72static int ext4_sync_fs(struct super_block *sb, int wait);
  73static int ext4_remount(struct super_block *sb, int *flags, char *data);
  74static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  75static int ext4_unfreeze(struct super_block *sb);
  76static int ext4_freeze(struct super_block *sb);
  77static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  78                       const char *dev_name, void *data);
  79static inline int ext2_feature_set_ok(struct super_block *sb);
  80static inline int ext3_feature_set_ok(struct super_block *sb);
  81static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  82static void ext4_destroy_lazyinit_thread(void);
  83static void ext4_unregister_li_request(struct super_block *sb);
  84static void ext4_clear_request_list(void);
  85static int ext4_reserve_clusters(struct ext4_sb_info *, ext4_fsblk_t);
  86
  87#if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
  88static struct file_system_type ext2_fs_type = {
  89        .owner          = THIS_MODULE,
  90        .name           = "ext2",
  91        .mount          = ext4_mount,
  92        .kill_sb        = kill_block_super,
  93        .fs_flags       = FS_REQUIRES_DEV,
  94};
  95MODULE_ALIAS_FS("ext2");
  96MODULE_ALIAS("ext2");
  97#define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
  98#else
  99#define IS_EXT2_SB(sb) (0)
 100#endif
 101
 102
 103#if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
 104static struct file_system_type ext3_fs_type = {
 105        .owner          = THIS_MODULE,
 106        .name           = "ext3",
 107        .mount          = ext4_mount,
 108        .kill_sb        = kill_block_super,
 109        .fs_flags       = FS_REQUIRES_DEV,
 110};
 111MODULE_ALIAS_FS("ext3");
 112MODULE_ALIAS("ext3");
 113#define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 114#else
 115#define IS_EXT3_SB(sb) (0)
 116#endif
 117
 118static int ext4_verify_csum_type(struct super_block *sb,
 119                                 struct ext4_super_block *es)
 120{
 121        if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
 122                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
 123                return 1;
 124
 125        return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 126}
 127
 128static __le32 ext4_superblock_csum(struct super_block *sb,
 129                                   struct ext4_super_block *es)
 130{
 131        struct ext4_sb_info *sbi = EXT4_SB(sb);
 132        int offset = offsetof(struct ext4_super_block, s_checksum);
 133        __u32 csum;
 134
 135        csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 136
 137        return cpu_to_le32(csum);
 138}
 139
 140static int ext4_superblock_csum_verify(struct super_block *sb,
 141                                       struct ext4_super_block *es)
 142{
 143        if (!ext4_has_metadata_csum(sb))
 144                return 1;
 145
 146        return es->s_checksum == ext4_superblock_csum(sb, es);
 147}
 148
 149void ext4_superblock_csum_set(struct super_block *sb)
 150{
 151        struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 152
 153        if (!ext4_has_metadata_csum(sb))
 154                return;
 155
 156        es->s_checksum = ext4_superblock_csum(sb, es);
 157}
 158
 159void *ext4_kvmalloc(size_t size, gfp_t flags)
 160{
 161        void *ret;
 162
 163        ret = kmalloc(size, flags | __GFP_NOWARN);
 164        if (!ret)
 165                ret = __vmalloc(size, flags, PAGE_KERNEL);
 166        return ret;
 167}
 168
 169void *ext4_kvzalloc(size_t size, gfp_t flags)
 170{
 171        void *ret;
 172
 173        ret = kzalloc(size, flags | __GFP_NOWARN);
 174        if (!ret)
 175                ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 176        return ret;
 177}
 178
 179ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 180                               struct ext4_group_desc *bg)
 181{
 182        return le32_to_cpu(bg->bg_block_bitmap_lo) |
 183                (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 184                 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 185}
 186
 187ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 188                               struct ext4_group_desc *bg)
 189{
 190        return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 191                (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 192                 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 193}
 194
 195ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 196                              struct ext4_group_desc *bg)
 197{
 198        return le32_to_cpu(bg->bg_inode_table_lo) |
 199                (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 200                 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 201}
 202
 203__u32 ext4_free_group_clusters(struct super_block *sb,
 204                               struct ext4_group_desc *bg)
 205{
 206        return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 207                (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 208                 (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 209}
 210
 211__u32 ext4_free_inodes_count(struct super_block *sb,
 212                              struct ext4_group_desc *bg)
 213{
 214        return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 215                (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 216                 (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 217}
 218
 219__u32 ext4_used_dirs_count(struct super_block *sb,
 220                              struct ext4_group_desc *bg)
 221{
 222        return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 223                (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 224                 (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 225}
 226
 227__u32 ext4_itable_unused_count(struct super_block *sb,
 228                              struct ext4_group_desc *bg)
 229{
 230        return le16_to_cpu(bg->bg_itable_unused_lo) |
 231                (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 232                 (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 233}
 234
 235void ext4_block_bitmap_set(struct super_block *sb,
 236                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 237{
 238        bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 239        if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 240                bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 241}
 242
 243void ext4_inode_bitmap_set(struct super_block *sb,
 244                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 245{
 246        bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 247        if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 248                bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 249}
 250
 251void ext4_inode_table_set(struct super_block *sb,
 252                          struct ext4_group_desc *bg, ext4_fsblk_t blk)
 253{
 254        bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 255        if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 256                bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 257}
 258
 259void ext4_free_group_clusters_set(struct super_block *sb,
 260                                  struct ext4_group_desc *bg, __u32 count)
 261{
 262        bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 263        if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 264                bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 265}
 266
 267void ext4_free_inodes_set(struct super_block *sb,
 268                          struct ext4_group_desc *bg, __u32 count)
 269{
 270        bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 271        if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 272                bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 273}
 274
 275void ext4_used_dirs_set(struct super_block *sb,
 276                          struct ext4_group_desc *bg, __u32 count)
 277{
 278        bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 279        if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 280                bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 281}
 282
 283void ext4_itable_unused_set(struct super_block *sb,
 284                          struct ext4_group_desc *bg, __u32 count)
 285{
 286        bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 287        if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 288                bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 289}
 290
 291
 292static void __save_error_info(struct super_block *sb, const char *func,
 293                            unsigned int line)
 294{
 295        struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 296
 297        EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 298        if (bdev_read_only(sb->s_bdev))
 299                return;
 300        es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 301        es->s_last_error_time = cpu_to_le32(get_seconds());
 302        strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 303        es->s_last_error_line = cpu_to_le32(line);
 304        if (!es->s_first_error_time) {
 305                es->s_first_error_time = es->s_last_error_time;
 306                strncpy(es->s_first_error_func, func,
 307                        sizeof(es->s_first_error_func));
 308                es->s_first_error_line = cpu_to_le32(line);
 309                es->s_first_error_ino = es->s_last_error_ino;
 310                es->s_first_error_block = es->s_last_error_block;
 311        }
 312        /*
 313         * Start the daily error reporting function if it hasn't been
 314         * started already
 315         */
 316        if (!es->s_error_count)
 317                mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 318        le32_add_cpu(&es->s_error_count, 1);
 319}
 320
 321static void save_error_info(struct super_block *sb, const char *func,
 322                            unsigned int line)
 323{
 324        __save_error_info(sb, func, line);
 325        ext4_commit_super(sb, 1);
 326}
 327
 328static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 329{
 330        struct super_block              *sb = journal->j_private;
 331        struct ext4_sb_info             *sbi = EXT4_SB(sb);
 332        int                             error = is_journal_aborted(journal);
 333        struct ext4_journal_cb_entry    *jce;
 334
 335        BUG_ON(txn->t_state == T_FINISHED);
 336        spin_lock(&sbi->s_md_lock);
 337        while (!list_empty(&txn->t_private_list)) {
 338                jce = list_entry(txn->t_private_list.next,
 339                                 struct ext4_journal_cb_entry, jce_list);
 340                list_del_init(&jce->jce_list);
 341                spin_unlock(&sbi->s_md_lock);
 342                jce->jce_func(sb, jce, error);
 343                spin_lock(&sbi->s_md_lock);
 344        }
 345        spin_unlock(&sbi->s_md_lock);
 346}
 347
 348/* Deal with the reporting of failure conditions on a filesystem such as
 349 * inconsistencies detected or read IO failures.
 350 *
 351 * On ext2, we can store the error state of the filesystem in the
 352 * superblock.  That is not possible on ext4, because we may have other
 353 * write ordering constraints on the superblock which prevent us from
 354 * writing it out straight away; and given that the journal is about to
 355 * be aborted, we can't rely on the current, or future, transactions to
 356 * write out the superblock safely.
 357 *
 358 * We'll just use the jbd2_journal_abort() error code to record an error in
 359 * the journal instead.  On recovery, the journal will complain about
 360 * that error until we've noted it down and cleared it.
 361 */
 362
 363static void ext4_handle_error(struct super_block *sb)
 364{
 365        if (sb->s_flags & MS_RDONLY)
 366                return;
 367
 368        if (!test_opt(sb, ERRORS_CONT)) {
 369                journal_t *journal = EXT4_SB(sb)->s_journal;
 370
 371                EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 372                if (journal)
 373                        jbd2_journal_abort(journal, -EIO);
 374        }
 375        if (test_opt(sb, ERRORS_RO)) {
 376                ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 377                /*
 378                 * Make sure updated value of ->s_mount_flags will be visible
 379                 * before ->s_flags update
 380                 */
 381                smp_wmb();
 382                sb->s_flags |= MS_RDONLY;
 383        }
 384        if (test_opt(sb, ERRORS_PANIC))
 385                panic("EXT4-fs (device %s): panic forced after error\n",
 386                        sb->s_id);
 387}
 388
 389#define ext4_error_ratelimit(sb)                                        \
 390                ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 391                             "EXT4-fs error")
 392
 393void __ext4_error(struct super_block *sb, const char *function,
 394                  unsigned int line, const char *fmt, ...)
 395{
 396        struct va_format vaf;
 397        va_list args;
 398
 399        if (ext4_error_ratelimit(sb)) {
 400                va_start(args, fmt);
 401                vaf.fmt = fmt;
 402                vaf.va = &args;
 403                printk(KERN_CRIT
 404                       "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 405                       sb->s_id, function, line, current->comm, &vaf);
 406                va_end(args);
 407        }
 408        save_error_info(sb, function, line);
 409        ext4_handle_error(sb);
 410}
 411
 412void __ext4_error_inode(struct inode *inode, const char *function,
 413                        unsigned int line, ext4_fsblk_t block,
 414                        const char *fmt, ...)
 415{
 416        va_list args;
 417        struct va_format vaf;
 418        struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 419
 420        es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 421        es->s_last_error_block = cpu_to_le64(block);
 422        if (ext4_error_ratelimit(inode->i_sb)) {
 423                va_start(args, fmt);
 424                vaf.fmt = fmt;
 425                vaf.va = &args;
 426                if (block)
 427                        printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 428                               "inode #%lu: block %llu: comm %s: %pV\n",
 429                               inode->i_sb->s_id, function, line, inode->i_ino,
 430                               block, current->comm, &vaf);
 431                else
 432                        printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 433                               "inode #%lu: comm %s: %pV\n",
 434                               inode->i_sb->s_id, function, line, inode->i_ino,
 435                               current->comm, &vaf);
 436                va_end(args);
 437        }
 438        save_error_info(inode->i_sb, function, line);
 439        ext4_handle_error(inode->i_sb);
 440}
 441
 442void __ext4_error_file(struct file *file, const char *function,
 443                       unsigned int line, ext4_fsblk_t block,
 444                       const char *fmt, ...)
 445{
 446        va_list args;
 447        struct va_format vaf;
 448        struct ext4_super_block *es;
 449        struct inode *inode = file_inode(file);
 450        char pathname[80], *path;
 451
 452        es = EXT4_SB(inode->i_sb)->s_es;
 453        es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 454        if (ext4_error_ratelimit(inode->i_sb)) {
 455                path = file_path(file, pathname, sizeof(pathname));
 456                if (IS_ERR(path))
 457                        path = "(unknown)";
 458                va_start(args, fmt);
 459                vaf.fmt = fmt;
 460                vaf.va = &args;
 461                if (block)
 462                        printk(KERN_CRIT
 463                               "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 464                               "block %llu: comm %s: path %s: %pV\n",
 465                               inode->i_sb->s_id, function, line, inode->i_ino,
 466                               block, current->comm, path, &vaf);
 467                else
 468                        printk(KERN_CRIT
 469                               "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 470                               "comm %s: path %s: %pV\n",
 471                               inode->i_sb->s_id, function, line, inode->i_ino,
 472                               current->comm, path, &vaf);
 473                va_end(args);
 474        }
 475        save_error_info(inode->i_sb, function, line);
 476        ext4_handle_error(inode->i_sb);
 477}
 478
 479const char *ext4_decode_error(struct super_block *sb, int errno,
 480                              char nbuf[16])
 481{
 482        char *errstr = NULL;
 483
 484        switch (errno) {
 485        case -EIO:
 486                errstr = "IO failure";
 487                break;
 488        case -ENOMEM:
 489                errstr = "Out of memory";
 490                break;
 491        case -EROFS:
 492                if (!sb || (EXT4_SB(sb)->s_journal &&
 493                            EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 494                        errstr = "Journal has aborted";
 495                else
 496                        errstr = "Readonly filesystem";
 497                break;
 498        default:
 499                /* If the caller passed in an extra buffer for unknown
 500                 * errors, textualise them now.  Else we just return
 501                 * NULL. */
 502                if (nbuf) {
 503                        /* Check for truncated error codes... */
 504                        if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 505                                errstr = nbuf;
 506                }
 507                break;
 508        }
 509
 510        return errstr;
 511}
 512
 513/* __ext4_std_error decodes expected errors from journaling functions
 514 * automatically and invokes the appropriate error response.  */
 515
 516void __ext4_std_error(struct super_block *sb, const char *function,
 517                      unsigned int line, int errno)
 518{
 519        char nbuf[16];
 520        const char *errstr;
 521
 522        /* Special case: if the error is EROFS, and we're not already
 523         * inside a transaction, then there's really no point in logging
 524         * an error. */
 525        if (errno == -EROFS && journal_current_handle() == NULL &&
 526            (sb->s_flags & MS_RDONLY))
 527                return;
 528
 529        if (ext4_error_ratelimit(sb)) {
 530                errstr = ext4_decode_error(sb, errno, nbuf);
 531                printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 532                       sb->s_id, function, line, errstr);
 533        }
 534
 535        save_error_info(sb, function, line);
 536        ext4_handle_error(sb);
 537}
 538
 539/*
 540 * ext4_abort is a much stronger failure handler than ext4_error.  The
 541 * abort function may be used to deal with unrecoverable failures such
 542 * as journal IO errors or ENOMEM at a critical moment in log management.
 543 *
 544 * We unconditionally force the filesystem into an ABORT|READONLY state,
 545 * unless the error response on the fs has been set to panic in which
 546 * case we take the easy way out and panic immediately.
 547 */
 548
 549void __ext4_abort(struct super_block *sb, const char *function,
 550                unsigned int line, const char *fmt, ...)
 551{
 552        va_list args;
 553
 554        save_error_info(sb, function, line);
 555        va_start(args, fmt);
 556        printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
 557               function, line);
 558        vprintk(fmt, args);
 559        printk("\n");
 560        va_end(args);
 561
 562        if ((sb->s_flags & MS_RDONLY) == 0) {
 563                ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 564                EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 565                /*
 566                 * Make sure updated value of ->s_mount_flags will be visible
 567                 * before ->s_flags update
 568                 */
 569                smp_wmb();
 570                sb->s_flags |= MS_RDONLY;
 571                if (EXT4_SB(sb)->s_journal)
 572                        jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 573                save_error_info(sb, function, line);
 574        }
 575        if (test_opt(sb, ERRORS_PANIC))
 576                panic("EXT4-fs panic from previous error\n");
 577}
 578
 579void __ext4_msg(struct super_block *sb,
 580                const char *prefix, const char *fmt, ...)
 581{
 582        struct va_format vaf;
 583        va_list args;
 584
 585        if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 586                return;
 587
 588        va_start(args, fmt);
 589        vaf.fmt = fmt;
 590        vaf.va = &args;
 591        printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 592        va_end(args);
 593}
 594
 595#define ext4_warning_ratelimit(sb)                                      \
 596                ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 597                             "EXT4-fs warning")
 598
 599void __ext4_warning(struct super_block *sb, const char *function,
 600                    unsigned int line, const char *fmt, ...)
 601{
 602        struct va_format vaf;
 603        va_list args;
 604
 605        if (!ext4_warning_ratelimit(sb))
 606                return;
 607
 608        va_start(args, fmt);
 609        vaf.fmt = fmt;
 610        vaf.va = &args;
 611        printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 612               sb->s_id, function, line, &vaf);
 613        va_end(args);
 614}
 615
 616void __ext4_warning_inode(const struct inode *inode, const char *function,
 617                          unsigned int line, const char *fmt, ...)
 618{
 619        struct va_format vaf;
 620        va_list args;
 621
 622        if (!ext4_warning_ratelimit(inode->i_sb))
 623                return;
 624
 625        va_start(args, fmt);
 626        vaf.fmt = fmt;
 627        vaf.va = &args;
 628        printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 629               "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 630               function, line, inode->i_ino, current->comm, &vaf);
 631        va_end(args);
 632}
 633
 634void __ext4_grp_locked_error(const char *function, unsigned int line,
 635                             struct super_block *sb, ext4_group_t grp,
 636                             unsigned long ino, ext4_fsblk_t block,
 637                             const char *fmt, ...)
 638__releases(bitlock)
 639__acquires(bitlock)
 640{
 641        struct va_format vaf;
 642        va_list args;
 643        struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 644
 645        es->s_last_error_ino = cpu_to_le32(ino);
 646        es->s_last_error_block = cpu_to_le64(block);
 647        __save_error_info(sb, function, line);
 648
 649        if (ext4_error_ratelimit(sb)) {
 650                va_start(args, fmt);
 651                vaf.fmt = fmt;
 652                vaf.va = &args;
 653                printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 654                       sb->s_id, function, line, grp);
 655                if (ino)
 656                        printk(KERN_CONT "inode %lu: ", ino);
 657                if (block)
 658                        printk(KERN_CONT "block %llu:",
 659                               (unsigned long long) block);
 660                printk(KERN_CONT "%pV\n", &vaf);
 661                va_end(args);
 662        }
 663
 664        if (test_opt(sb, ERRORS_CONT)) {
 665                ext4_commit_super(sb, 0);
 666                return;
 667        }
 668
 669        ext4_unlock_group(sb, grp);
 670        ext4_handle_error(sb);
 671        /*
 672         * We only get here in the ERRORS_RO case; relocking the group
 673         * may be dangerous, but nothing bad will happen since the
 674         * filesystem will have already been marked read/only and the
 675         * journal has been aborted.  We return 1 as a hint to callers
 676         * who might what to use the return value from
 677         * ext4_grp_locked_error() to distinguish between the
 678         * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 679         * aggressively from the ext4 function in question, with a
 680         * more appropriate error code.
 681         */
 682        ext4_lock_group(sb, grp);
 683        return;
 684}
 685
 686void ext4_update_dynamic_rev(struct super_block *sb)
 687{
 688        struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 689
 690        if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 691                return;
 692
 693        ext4_warning(sb,
 694                     "updating to rev %d because of new feature flag, "
 695                     "running e2fsck is recommended",
 696                     EXT4_DYNAMIC_REV);
 697
 698        es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 699        es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 700        es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 701        /* leave es->s_feature_*compat flags alone */
 702        /* es->s_uuid will be set by e2fsck if empty */
 703
 704        /*
 705         * The rest of the superblock fields should be zero, and if not it
 706         * means they are likely already in use, so leave them alone.  We
 707         * can leave it up to e2fsck to clean up any inconsistencies there.
 708         */
 709}
 710
 711/*
 712 * Open the external journal device
 713 */
 714static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 715{
 716        struct block_device *bdev;
 717        char b[BDEVNAME_SIZE];
 718
 719        bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 720        if (IS_ERR(bdev))
 721                goto fail;
 722        return bdev;
 723
 724fail:
 725        ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 726                        __bdevname(dev, b), PTR_ERR(bdev));
 727        return NULL;
 728}
 729
 730/*
 731 * Release the journal device
 732 */
 733static void ext4_blkdev_put(struct block_device *bdev)
 734{
 735        blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 736}
 737
 738static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 739{
 740        struct block_device *bdev;
 741        bdev = sbi->journal_bdev;
 742        if (bdev) {
 743                ext4_blkdev_put(bdev);
 744                sbi->journal_bdev = NULL;
 745        }
 746}
 747
 748static inline struct inode *orphan_list_entry(struct list_head *l)
 749{
 750        return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 751}
 752
 753static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 754{
 755        struct list_head *l;
 756
 757        ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 758                 le32_to_cpu(sbi->s_es->s_last_orphan));
 759
 760        printk(KERN_ERR "sb_info orphan list:\n");
 761        list_for_each(l, &sbi->s_orphan) {
 762                struct inode *inode = orphan_list_entry(l);
 763                printk(KERN_ERR "  "
 764                       "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 765                       inode->i_sb->s_id, inode->i_ino, inode,
 766                       inode->i_mode, inode->i_nlink,
 767                       NEXT_ORPHAN(inode));
 768        }
 769}
 770
 771static void ext4_put_super(struct super_block *sb)
 772{
 773        struct ext4_sb_info *sbi = EXT4_SB(sb);
 774        struct ext4_super_block *es = sbi->s_es;
 775        int i, err;
 776
 777        ext4_unregister_li_request(sb);
 778        dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 779
 780        flush_workqueue(sbi->rsv_conversion_wq);
 781        destroy_workqueue(sbi->rsv_conversion_wq);
 782
 783        if (sbi->s_journal) {
 784                err = jbd2_journal_destroy(sbi->s_journal);
 785                sbi->s_journal = NULL;
 786                if (err < 0)
 787                        ext4_abort(sb, "Couldn't clean up the journal");
 788        }
 789
 790        ext4_es_unregister_shrinker(sbi);
 791        del_timer_sync(&sbi->s_err_report);
 792        ext4_release_system_zone(sb);
 793        ext4_mb_release(sb);
 794        ext4_ext_release(sb);
 795        ext4_xattr_put_super(sb);
 796
 797        if (!(sb->s_flags & MS_RDONLY)) {
 798                EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
 799                es->s_state = cpu_to_le16(sbi->s_mount_state);
 800        }
 801        if (!(sb->s_flags & MS_RDONLY))
 802                ext4_commit_super(sb, 1);
 803
 804        if (sbi->s_proc) {
 805                remove_proc_entry("options", sbi->s_proc);
 806                remove_proc_entry(sb->s_id, ext4_proc_root);
 807        }
 808        kobject_del(&sbi->s_kobj);
 809
 810        for (i = 0; i < sbi->s_gdb_count; i++)
 811                brelse(sbi->s_group_desc[i]);
 812        kvfree(sbi->s_group_desc);
 813        kvfree(sbi->s_flex_groups);
 814        percpu_counter_destroy(&sbi->s_freeclusters_counter);
 815        percpu_counter_destroy(&sbi->s_freeinodes_counter);
 816        percpu_counter_destroy(&sbi->s_dirs_counter);
 817        percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 818        brelse(sbi->s_sbh);
 819#ifdef CONFIG_QUOTA
 820        for (i = 0; i < EXT4_MAXQUOTAS; i++)
 821                kfree(sbi->s_qf_names[i]);
 822#endif
 823
 824        /* Debugging code just in case the in-memory inode orphan list
 825         * isn't empty.  The on-disk one can be non-empty if we've
 826         * detected an error and taken the fs readonly, but the
 827         * in-memory list had better be clean by this point. */
 828        if (!list_empty(&sbi->s_orphan))
 829                dump_orphan_list(sb, sbi);
 830        J_ASSERT(list_empty(&sbi->s_orphan));
 831
 832        sync_blockdev(sb->s_bdev);
 833        invalidate_bdev(sb->s_bdev);
 834        if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 835                /*
 836                 * Invalidate the journal device's buffers.  We don't want them
 837                 * floating about in memory - the physical journal device may
 838                 * hotswapped, and it breaks the `ro-after' testing code.
 839                 */
 840                sync_blockdev(sbi->journal_bdev);
 841                invalidate_bdev(sbi->journal_bdev);
 842                ext4_blkdev_remove(sbi);
 843        }
 844        if (sbi->s_mb_cache) {
 845                ext4_xattr_destroy_cache(sbi->s_mb_cache);
 846                sbi->s_mb_cache = NULL;
 847        }
 848        if (sbi->s_mmp_tsk)
 849                kthread_stop(sbi->s_mmp_tsk);
 850        sb->s_fs_info = NULL;
 851        /*
 852         * Now that we are completely done shutting down the
 853         * superblock, we need to actually destroy the kobject.
 854         */
 855        kobject_put(&sbi->s_kobj);
 856        wait_for_completion(&sbi->s_kobj_unregister);
 857        if (sbi->s_chksum_driver)
 858                crypto_free_shash(sbi->s_chksum_driver);
 859        kfree(sbi->s_blockgroup_lock);
 860        kfree(sbi);
 861}
 862
 863static struct kmem_cache *ext4_inode_cachep;
 864
 865/*
 866 * Called inside transaction, so use GFP_NOFS
 867 */
 868static struct inode *ext4_alloc_inode(struct super_block *sb)
 869{
 870        struct ext4_inode_info *ei;
 871
 872        ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 873        if (!ei)
 874                return NULL;
 875
 876        ei->vfs_inode.i_version = 1;
 877        spin_lock_init(&ei->i_raw_lock);
 878        INIT_LIST_HEAD(&ei->i_prealloc_list);
 879        spin_lock_init(&ei->i_prealloc_lock);
 880        ext4_es_init_tree(&ei->i_es_tree);
 881        rwlock_init(&ei->i_es_lock);
 882        INIT_LIST_HEAD(&ei->i_es_list);
 883        ei->i_es_all_nr = 0;
 884        ei->i_es_shk_nr = 0;
 885        ei->i_es_shrink_lblk = 0;
 886        ei->i_reserved_data_blocks = 0;
 887        ei->i_reserved_meta_blocks = 0;
 888        ei->i_allocated_meta_blocks = 0;
 889        ei->i_da_metadata_calc_len = 0;
 890        ei->i_da_metadata_calc_last_lblock = 0;
 891        spin_lock_init(&(ei->i_block_reservation_lock));
 892#ifdef CONFIG_QUOTA
 893        ei->i_reserved_quota = 0;
 894        memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
 895#endif
 896        ei->jinode = NULL;
 897        INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
 898        spin_lock_init(&ei->i_completed_io_lock);
 899        ei->i_sync_tid = 0;
 900        ei->i_datasync_tid = 0;
 901        atomic_set(&ei->i_ioend_count, 0);
 902        atomic_set(&ei->i_unwritten, 0);
 903        INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
 904#ifdef CONFIG_EXT4_FS_ENCRYPTION
 905        ei->i_crypt_info = NULL;
 906#endif
 907        return &ei->vfs_inode;
 908}
 909
 910static int ext4_drop_inode(struct inode *inode)
 911{
 912        int drop = generic_drop_inode(inode);
 913
 914        trace_ext4_drop_inode(inode, drop);
 915        return drop;
 916}
 917
 918static void ext4_i_callback(struct rcu_head *head)
 919{
 920        struct inode *inode = container_of(head, struct inode, i_rcu);
 921        kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 922}
 923
 924static void ext4_destroy_inode(struct inode *inode)
 925{
 926        if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 927                ext4_msg(inode->i_sb, KERN_ERR,
 928                         "Inode %lu (%p): orphan list check failed!",
 929                         inode->i_ino, EXT4_I(inode));
 930                print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 931                                EXT4_I(inode), sizeof(struct ext4_inode_info),
 932                                true);
 933                dump_stack();
 934        }
 935        call_rcu(&inode->i_rcu, ext4_i_callback);
 936}
 937
 938static void init_once(void *foo)
 939{
 940        struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 941
 942        INIT_LIST_HEAD(&ei->i_orphan);
 943        init_rwsem(&ei->xattr_sem);
 944        init_rwsem(&ei->i_data_sem);
 945        inode_init_once(&ei->vfs_inode);
 946}
 947
 948static int __init init_inodecache(void)
 949{
 950        ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
 951                                             sizeof(struct ext4_inode_info),
 952                                             0, (SLAB_RECLAIM_ACCOUNT|
 953                                                SLAB_MEM_SPREAD),
 954                                             init_once);
 955        if (ext4_inode_cachep == NULL)
 956                return -ENOMEM;
 957        return 0;
 958}
 959
 960static void destroy_inodecache(void)
 961{
 962        /*
 963         * Make sure all delayed rcu free inodes are flushed before we
 964         * destroy cache.
 965         */
 966        rcu_barrier();
 967        kmem_cache_destroy(ext4_inode_cachep);
 968}
 969
 970void ext4_clear_inode(struct inode *inode)
 971{
 972        invalidate_inode_buffers(inode);
 973        clear_inode(inode);
 974        dquot_drop(inode);
 975        ext4_discard_preallocations(inode);
 976        ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
 977        if (EXT4_I(inode)->jinode) {
 978                jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
 979                                               EXT4_I(inode)->jinode);
 980                jbd2_free_inode(EXT4_I(inode)->jinode);
 981                EXT4_I(inode)->jinode = NULL;
 982        }
 983#ifdef CONFIG_EXT4_FS_ENCRYPTION
 984        if (EXT4_I(inode)->i_crypt_info)
 985                ext4_free_encryption_info(inode, EXT4_I(inode)->i_crypt_info);
 986#endif
 987}
 988
 989static struct inode *ext4_nfs_get_inode(struct super_block *sb,
 990                                        u64 ino, u32 generation)
 991{
 992        struct inode *inode;
 993
 994        if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
 995                return ERR_PTR(-ESTALE);
 996        if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
 997                return ERR_PTR(-ESTALE);
 998
 999        /* iget isn't really right if the inode is currently unallocated!!
1000         *
1001         * ext4_read_inode will return a bad_inode if the inode had been
1002         * deleted, so we should be safe.
1003         *
1004         * Currently we don't know the generation for parent directory, so
1005         * a generation of 0 means "accept any"
1006         */
1007        inode = ext4_iget_normal(sb, ino);
1008        if (IS_ERR(inode))
1009                return ERR_CAST(inode);
1010        if (generation && inode->i_generation != generation) {
1011                iput(inode);
1012                return ERR_PTR(-ESTALE);
1013        }
1014
1015        return inode;
1016}
1017
1018static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1019                                        int fh_len, int fh_type)
1020{
1021        return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1022                                    ext4_nfs_get_inode);
1023}
1024
1025static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1026                                        int fh_len, int fh_type)
1027{
1028        return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1029                                    ext4_nfs_get_inode);
1030}
1031
1032/*
1033 * Try to release metadata pages (indirect blocks, directories) which are
1034 * mapped via the block device.  Since these pages could have journal heads
1035 * which would prevent try_to_free_buffers() from freeing them, we must use
1036 * jbd2 layer's try_to_free_buffers() function to release them.
1037 */
1038static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1039                                 gfp_t wait)
1040{
1041        journal_t *journal = EXT4_SB(sb)->s_journal;
1042
1043        WARN_ON(PageChecked(page));
1044        if (!page_has_buffers(page))
1045                return 0;
1046        if (journal)
1047                return jbd2_journal_try_to_free_buffers(journal, page,
1048                                                        wait & ~__GFP_WAIT);
1049        return try_to_free_buffers(page);
1050}
1051
1052#ifdef CONFIG_QUOTA
1053#define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1054#define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1055
1056static int ext4_write_dquot(struct dquot *dquot);
1057static int ext4_acquire_dquot(struct dquot *dquot);
1058static int ext4_release_dquot(struct dquot *dquot);
1059static int ext4_mark_dquot_dirty(struct dquot *dquot);
1060static int ext4_write_info(struct super_block *sb, int type);
1061static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1062                         struct path *path);
1063static int ext4_quota_off(struct super_block *sb, int type);
1064static int ext4_quota_on_mount(struct super_block *sb, int type);
1065static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1066                               size_t len, loff_t off);
1067static ssize_t ext4_quota_write(struct super_block *sb, int type,
1068                                const char *data, size_t len, loff_t off);
1069static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1070                             unsigned int flags);
1071static int ext4_enable_quotas(struct super_block *sb);
1072
1073static struct dquot **ext4_get_dquots(struct inode *inode)
1074{
1075        return EXT4_I(inode)->i_dquot;
1076}
1077
1078static const struct dquot_operations ext4_quota_operations = {
1079        .get_reserved_space = ext4_get_reserved_space,
1080        .write_dquot    = ext4_write_dquot,
1081        .acquire_dquot  = ext4_acquire_dquot,
1082        .release_dquot  = ext4_release_dquot,
1083        .mark_dirty     = ext4_mark_dquot_dirty,
1084        .write_info     = ext4_write_info,
1085        .alloc_dquot    = dquot_alloc,
1086        .destroy_dquot  = dquot_destroy,
1087};
1088
1089static const struct quotactl_ops ext4_qctl_operations = {
1090        .quota_on       = ext4_quota_on,
1091        .quota_off      = ext4_quota_off,
1092        .quota_sync     = dquot_quota_sync,
1093        .get_state      = dquot_get_state,
1094        .set_info       = dquot_set_dqinfo,
1095        .get_dqblk      = dquot_get_dqblk,
1096        .set_dqblk      = dquot_set_dqblk
1097};
1098#endif
1099
1100static const struct super_operations ext4_sops = {
1101        .alloc_inode    = ext4_alloc_inode,
1102        .destroy_inode  = ext4_destroy_inode,
1103        .write_inode    = ext4_write_inode,
1104        .dirty_inode    = ext4_dirty_inode,
1105        .drop_inode     = ext4_drop_inode,
1106        .evict_inode    = ext4_evict_inode,
1107        .put_super      = ext4_put_super,
1108        .sync_fs        = ext4_sync_fs,
1109        .freeze_fs      = ext4_freeze,
1110        .unfreeze_fs    = ext4_unfreeze,
1111        .statfs         = ext4_statfs,
1112        .remount_fs     = ext4_remount,
1113        .show_options   = ext4_show_options,
1114#ifdef CONFIG_QUOTA
1115        .quota_read     = ext4_quota_read,
1116        .quota_write    = ext4_quota_write,
1117        .get_dquots     = ext4_get_dquots,
1118#endif
1119        .bdev_try_to_free_page = bdev_try_to_free_page,
1120};
1121
1122static const struct export_operations ext4_export_ops = {
1123        .fh_to_dentry = ext4_fh_to_dentry,
1124        .fh_to_parent = ext4_fh_to_parent,
1125        .get_parent = ext4_get_parent,
1126};
1127
1128enum {
1129        Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1130        Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1131        Opt_nouid32, Opt_debug, Opt_removed,
1132        Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1133        Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1134        Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1135        Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1136        Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1137        Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1138        Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1139        Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1140        Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1141        Opt_usrquota, Opt_grpquota, Opt_i_version, Opt_dax,
1142        Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1143        Opt_lazytime, Opt_nolazytime,
1144        Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1145        Opt_inode_readahead_blks, Opt_journal_ioprio,
1146        Opt_dioread_nolock, Opt_dioread_lock,
1147        Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1148        Opt_max_dir_size_kb, Opt_nojournal_checksum,
1149};
1150
1151static const match_table_t tokens = {
1152        {Opt_bsd_df, "bsddf"},
1153        {Opt_minix_df, "minixdf"},
1154        {Opt_grpid, "grpid"},
1155        {Opt_grpid, "bsdgroups"},
1156        {Opt_nogrpid, "nogrpid"},
1157        {Opt_nogrpid, "sysvgroups"},
1158        {Opt_resgid, "resgid=%u"},
1159        {Opt_resuid, "resuid=%u"},
1160        {Opt_sb, "sb=%u"},
1161        {Opt_err_cont, "errors=continue"},
1162        {Opt_err_panic, "errors=panic"},
1163        {Opt_err_ro, "errors=remount-ro"},
1164        {Opt_nouid32, "nouid32"},
1165        {Opt_debug, "debug"},
1166        {Opt_removed, "oldalloc"},
1167        {Opt_removed, "orlov"},
1168        {Opt_user_xattr, "user_xattr"},
1169        {Opt_nouser_xattr, "nouser_xattr"},
1170        {Opt_acl, "acl"},
1171        {Opt_noacl, "noacl"},
1172        {Opt_noload, "norecovery"},
1173        {Opt_noload, "noload"},
1174        {Opt_removed, "nobh"},
1175        {Opt_removed, "bh"},
1176        {Opt_commit, "commit=%u"},
1177        {Opt_min_batch_time, "min_batch_time=%u"},
1178        {Opt_max_batch_time, "max_batch_time=%u"},
1179        {Opt_journal_dev, "journal_dev=%u"},
1180        {Opt_journal_path, "journal_path=%s"},
1181        {Opt_journal_checksum, "journal_checksum"},
1182        {Opt_nojournal_checksum, "nojournal_checksum"},
1183        {Opt_journal_async_commit, "journal_async_commit"},
1184        {Opt_abort, "abort"},
1185        {Opt_data_journal, "data=journal"},
1186        {Opt_data_ordered, "data=ordered"},
1187        {Opt_data_writeback, "data=writeback"},
1188        {Opt_data_err_abort, "data_err=abort"},
1189        {Opt_data_err_ignore, "data_err=ignore"},
1190        {Opt_offusrjquota, "usrjquota="},
1191        {Opt_usrjquota, "usrjquota=%s"},
1192        {Opt_offgrpjquota, "grpjquota="},
1193        {Opt_grpjquota, "grpjquota=%s"},
1194        {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1195        {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1196        {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1197        {Opt_grpquota, "grpquota"},
1198        {Opt_noquota, "noquota"},
1199        {Opt_quota, "quota"},
1200        {Opt_usrquota, "usrquota"},
1201        {Opt_barrier, "barrier=%u"},
1202        {Opt_barrier, "barrier"},
1203        {Opt_nobarrier, "nobarrier"},
1204        {Opt_i_version, "i_version"},
1205        {Opt_dax, "dax"},
1206        {Opt_stripe, "stripe=%u"},
1207        {Opt_delalloc, "delalloc"},
1208        {Opt_lazytime, "lazytime"},
1209        {Opt_nolazytime, "nolazytime"},
1210        {Opt_nodelalloc, "nodelalloc"},
1211        {Opt_removed, "mblk_io_submit"},
1212        {Opt_removed, "nomblk_io_submit"},
1213        {Opt_block_validity, "block_validity"},
1214        {Opt_noblock_validity, "noblock_validity"},
1215        {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1216        {Opt_journal_ioprio, "journal_ioprio=%u"},
1217        {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1218        {Opt_auto_da_alloc, "auto_da_alloc"},
1219        {Opt_noauto_da_alloc, "noauto_da_alloc"},
1220        {Opt_dioread_nolock, "dioread_nolock"},
1221        {Opt_dioread_lock, "dioread_lock"},
1222        {Opt_discard, "discard"},
1223        {Opt_nodiscard, "nodiscard"},
1224        {Opt_init_itable, "init_itable=%u"},
1225        {Opt_init_itable, "init_itable"},
1226        {Opt_noinit_itable, "noinit_itable"},
1227        {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1228        {Opt_test_dummy_encryption, "test_dummy_encryption"},
1229        {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1230        {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1231        {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1232        {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1233        {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1234        {Opt_err, NULL},
1235};
1236
1237static ext4_fsblk_t get_sb_block(void **data)
1238{
1239        ext4_fsblk_t    sb_block;
1240        char            *options = (char *) *data;
1241
1242        if (!options || strncmp(options, "sb=", 3) != 0)
1243                return 1;       /* Default location */
1244
1245        options += 3;
1246        /* TODO: use simple_strtoll with >32bit ext4 */
1247        sb_block = simple_strtoul(options, &options, 0);
1248        if (*options && *options != ',') {
1249                printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1250                       (char *) *data);
1251                return 1;
1252        }
1253        if (*options == ',')
1254                options++;
1255        *data = (void *) options;
1256
1257        return sb_block;
1258}
1259
1260#define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1261static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1262        "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1263
1264#ifdef CONFIG_QUOTA
1265static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1266{
1267        struct ext4_sb_info *sbi = EXT4_SB(sb);
1268        char *qname;
1269        int ret = -1;
1270
1271        if (sb_any_quota_loaded(sb) &&
1272                !sbi->s_qf_names[qtype]) {
1273                ext4_msg(sb, KERN_ERR,
1274                        "Cannot change journaled "
1275                        "quota options when quota turned on");
1276                return -1;
1277        }
1278        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1279                ext4_msg(sb, KERN_ERR, "Cannot set journaled quota options "
1280                         "when QUOTA feature is enabled");
1281                return -1;
1282        }
1283        qname = match_strdup(args);
1284        if (!qname) {
1285                ext4_msg(sb, KERN_ERR,
1286                        "Not enough memory for storing quotafile name");
1287                return -1;
1288        }
1289        if (sbi->s_qf_names[qtype]) {
1290                if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1291                        ret = 1;
1292                else
1293                        ext4_msg(sb, KERN_ERR,
1294                                 "%s quota file already specified",
1295                                 QTYPE2NAME(qtype));
1296                goto errout;
1297        }
1298        if (strchr(qname, '/')) {
1299                ext4_msg(sb, KERN_ERR,
1300                        "quotafile must be on filesystem root");
1301                goto errout;
1302        }
1303        sbi->s_qf_names[qtype] = qname;
1304        set_opt(sb, QUOTA);
1305        return 1;
1306errout:
1307        kfree(qname);
1308        return ret;
1309}
1310
1311static int clear_qf_name(struct super_block *sb, int qtype)
1312{
1313
1314        struct ext4_sb_info *sbi = EXT4_SB(sb);
1315
1316        if (sb_any_quota_loaded(sb) &&
1317                sbi->s_qf_names[qtype]) {
1318                ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1319                        " when quota turned on");
1320                return -1;
1321        }
1322        kfree(sbi->s_qf_names[qtype]);
1323        sbi->s_qf_names[qtype] = NULL;
1324        return 1;
1325}
1326#endif
1327
1328#define MOPT_SET        0x0001
1329#define MOPT_CLEAR      0x0002
1330#define MOPT_NOSUPPORT  0x0004
1331#define MOPT_EXPLICIT   0x0008
1332#define MOPT_CLEAR_ERR  0x0010
1333#define MOPT_GTE0       0x0020
1334#ifdef CONFIG_QUOTA
1335#define MOPT_Q          0
1336#define MOPT_QFMT       0x0040
1337#else
1338#define MOPT_Q          MOPT_NOSUPPORT
1339#define MOPT_QFMT       MOPT_NOSUPPORT
1340#endif
1341#define MOPT_DATAJ      0x0080
1342#define MOPT_NO_EXT2    0x0100
1343#define MOPT_NO_EXT3    0x0200
1344#define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1345#define MOPT_STRING     0x0400
1346
1347static const struct mount_opts {
1348        int     token;
1349        int     mount_opt;
1350        int     flags;
1351} ext4_mount_opts[] = {
1352        {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1353        {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1354        {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1355        {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1356        {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1357        {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1358        {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1359         MOPT_EXT4_ONLY | MOPT_SET},
1360        {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1361         MOPT_EXT4_ONLY | MOPT_CLEAR},
1362        {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1363        {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1364        {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1365         MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1366        {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1367         MOPT_EXT4_ONLY | MOPT_CLEAR},
1368        {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1369         MOPT_EXT4_ONLY | MOPT_CLEAR},
1370        {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1371         MOPT_EXT4_ONLY | MOPT_SET},
1372        {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1373                                    EXT4_MOUNT_JOURNAL_CHECKSUM),
1374         MOPT_EXT4_ONLY | MOPT_SET},
1375        {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1376        {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1377        {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1378        {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1379        {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1380         MOPT_NO_EXT2 | MOPT_SET},
1381        {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1382         MOPT_NO_EXT2 | MOPT_CLEAR},
1383        {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1384        {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1385        {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1386        {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1387        {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1388        {Opt_commit, 0, MOPT_GTE0},
1389        {Opt_max_batch_time, 0, MOPT_GTE0},
1390        {Opt_min_batch_time, 0, MOPT_GTE0},
1391        {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1392        {Opt_init_itable, 0, MOPT_GTE0},
1393        {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1394        {Opt_stripe, 0, MOPT_GTE0},
1395        {Opt_resuid, 0, MOPT_GTE0},
1396        {Opt_resgid, 0, MOPT_GTE0},
1397        {Opt_journal_dev, 0, MOPT_GTE0},
1398        {Opt_journal_path, 0, MOPT_STRING},
1399        {Opt_journal_ioprio, 0, MOPT_GTE0},
1400        {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1401        {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1402        {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1403         MOPT_NO_EXT2 | MOPT_DATAJ},
1404        {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1405        {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1406#ifdef CONFIG_EXT4_FS_POSIX_ACL
1407        {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1408        {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1409#else
1410        {Opt_acl, 0, MOPT_NOSUPPORT},
1411        {Opt_noacl, 0, MOPT_NOSUPPORT},
1412#endif
1413        {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1414        {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1415        {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1416        {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1417                                                        MOPT_SET | MOPT_Q},
1418        {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1419                                                        MOPT_SET | MOPT_Q},
1420        {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1421                       EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1422        {Opt_usrjquota, 0, MOPT_Q},
1423        {Opt_grpjquota, 0, MOPT_Q},
1424        {Opt_offusrjquota, 0, MOPT_Q},
1425        {Opt_offgrpjquota, 0, MOPT_Q},
1426        {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1427        {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1428        {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1429        {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1430        {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1431        {Opt_err, 0, 0}
1432};
1433
1434static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1435                            substring_t *args, unsigned long *journal_devnum,
1436                            unsigned int *journal_ioprio, int is_remount)
1437{
1438        struct ext4_sb_info *sbi = EXT4_SB(sb);
1439        const struct mount_opts *m;
1440        kuid_t uid;
1441        kgid_t gid;
1442        int arg = 0;
1443
1444#ifdef CONFIG_QUOTA
1445        if (token == Opt_usrjquota)
1446                return set_qf_name(sb, USRQUOTA, &args[0]);
1447        else if (token == Opt_grpjquota)
1448                return set_qf_name(sb, GRPQUOTA, &args[0]);
1449        else if (token == Opt_offusrjquota)
1450                return clear_qf_name(sb, USRQUOTA);
1451        else if (token == Opt_offgrpjquota)
1452                return clear_qf_name(sb, GRPQUOTA);
1453#endif
1454        switch (token) {
1455        case Opt_noacl:
1456        case Opt_nouser_xattr:
1457                ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1458                break;
1459        case Opt_sb:
1460                return 1;       /* handled by get_sb_block() */
1461        case Opt_removed:
1462                ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1463                return 1;
1464        case Opt_abort:
1465                sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1466                return 1;
1467        case Opt_i_version:
1468                sb->s_flags |= MS_I_VERSION;
1469                return 1;
1470        case Opt_lazytime:
1471                sb->s_flags |= MS_LAZYTIME;
1472                return 1;
1473        case Opt_nolazytime:
1474                sb->s_flags &= ~MS_LAZYTIME;
1475                return 1;
1476        }
1477
1478        for (m = ext4_mount_opts; m->token != Opt_err; m++)
1479                if (token == m->token)
1480                        break;
1481
1482        if (m->token == Opt_err) {
1483                ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1484                         "or missing value", opt);
1485                return -1;
1486        }
1487
1488        if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1489                ext4_msg(sb, KERN_ERR,
1490                         "Mount option \"%s\" incompatible with ext2", opt);
1491                return -1;
1492        }
1493        if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1494                ext4_msg(sb, KERN_ERR,
1495                         "Mount option \"%s\" incompatible with ext3", opt);
1496                return -1;
1497        }
1498
1499        if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1500                return -1;
1501        if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1502                return -1;
1503        if (m->flags & MOPT_EXPLICIT)
1504                set_opt2(sb, EXPLICIT_DELALLOC);
1505        if (m->flags & MOPT_CLEAR_ERR)
1506                clear_opt(sb, ERRORS_MASK);
1507        if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1508                ext4_msg(sb, KERN_ERR, "Cannot change quota "
1509                         "options when quota turned on");
1510                return -1;
1511        }
1512
1513        if (m->flags & MOPT_NOSUPPORT) {
1514                ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1515        } else if (token == Opt_commit) {
1516                if (arg == 0)
1517                        arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1518                sbi->s_commit_interval = HZ * arg;
1519        } else if (token == Opt_max_batch_time) {
1520                sbi->s_max_batch_time = arg;
1521        } else if (token == Opt_min_batch_time) {
1522                sbi->s_min_batch_time = arg;
1523        } else if (token == Opt_inode_readahead_blks) {
1524                if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1525                        ext4_msg(sb, KERN_ERR,
1526                                 "EXT4-fs: inode_readahead_blks must be "
1527                                 "0 or a power of 2 smaller than 2^31");
1528                        return -1;
1529                }
1530                sbi->s_inode_readahead_blks = arg;
1531        } else if (token == Opt_init_itable) {
1532                set_opt(sb, INIT_INODE_TABLE);
1533                if (!args->from)
1534                        arg = EXT4_DEF_LI_WAIT_MULT;
1535                sbi->s_li_wait_mult = arg;
1536        } else if (token == Opt_max_dir_size_kb) {
1537                sbi->s_max_dir_size_kb = arg;
1538        } else if (token == Opt_stripe) {
1539                sbi->s_stripe = arg;
1540        } else if (token == Opt_resuid) {
1541                uid = make_kuid(current_user_ns(), arg);
1542                if (!uid_valid(uid)) {
1543                        ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1544                        return -1;
1545                }
1546                sbi->s_resuid = uid;
1547        } else if (token == Opt_resgid) {
1548                gid = make_kgid(current_user_ns(), arg);
1549                if (!gid_valid(gid)) {
1550                        ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1551                        return -1;
1552                }
1553                sbi->s_resgid = gid;
1554        } else if (token == Opt_journal_dev) {
1555                if (is_remount) {
1556                        ext4_msg(sb, KERN_ERR,
1557                                 "Cannot specify journal on remount");
1558                        return -1;
1559                }
1560                *journal_devnum = arg;
1561        } else if (token == Opt_journal_path) {
1562                char *journal_path;
1563                struct inode *journal_inode;
1564                struct path path;
1565                int error;
1566
1567                if (is_remount) {
1568                        ext4_msg(sb, KERN_ERR,
1569                                 "Cannot specify journal on remount");
1570                        return -1;
1571                }
1572                journal_path = match_strdup(&args[0]);
1573                if (!journal_path) {
1574                        ext4_msg(sb, KERN_ERR, "error: could not dup "
1575                                "journal device string");
1576                        return -1;
1577                }
1578
1579                error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1580                if (error) {
1581                        ext4_msg(sb, KERN_ERR, "error: could not find "
1582                                "journal device path: error %d", error);
1583                        kfree(journal_path);
1584                        return -1;
1585                }
1586
1587                journal_inode = d_inode(path.dentry);
1588                if (!S_ISBLK(journal_inode->i_mode)) {
1589                        ext4_msg(sb, KERN_ERR, "error: journal path %s "
1590                                "is not a block device", journal_path);
1591                        path_put(&path);
1592                        kfree(journal_path);
1593                        return -1;
1594                }
1595
1596                *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1597                path_put(&path);
1598                kfree(journal_path);
1599        } else if (token == Opt_journal_ioprio) {
1600                if (arg > 7) {
1601                        ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1602                                 " (must be 0-7)");
1603                        return -1;
1604                }
1605                *journal_ioprio =
1606                        IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1607        } else if (token == Opt_test_dummy_encryption) {
1608#ifdef CONFIG_EXT4_FS_ENCRYPTION
1609                sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1610                ext4_msg(sb, KERN_WARNING,
1611                         "Test dummy encryption mode enabled");
1612#else
1613                ext4_msg(sb, KERN_WARNING,
1614                         "Test dummy encryption mount option ignored");
1615#endif
1616        } else if (m->flags & MOPT_DATAJ) {
1617                if (is_remount) {
1618                        if (!sbi->s_journal)
1619                                ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1620                        else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1621                                ext4_msg(sb, KERN_ERR,
1622                                         "Cannot change data mode on remount");
1623                                return -1;
1624                        }
1625                } else {
1626                        clear_opt(sb, DATA_FLAGS);
1627                        sbi->s_mount_opt |= m->mount_opt;
1628                }
1629#ifdef CONFIG_QUOTA
1630        } else if (m->flags & MOPT_QFMT) {
1631                if (sb_any_quota_loaded(sb) &&
1632                    sbi->s_jquota_fmt != m->mount_opt) {
1633                        ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1634                                 "quota options when quota turned on");
1635                        return -1;
1636                }
1637                if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
1638                                               EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1639                        ext4_msg(sb, KERN_ERR,
1640                                 "Cannot set journaled quota options "
1641                                 "when QUOTA feature is enabled");
1642                        return -1;
1643                }
1644                sbi->s_jquota_fmt = m->mount_opt;
1645#endif
1646#ifndef CONFIG_FS_DAX
1647        } else if (token == Opt_dax) {
1648                ext4_msg(sb, KERN_INFO, "dax option not supported");
1649                return -1;
1650#endif
1651        } else {
1652                if (!args->from)
1653                        arg = 1;
1654                if (m->flags & MOPT_CLEAR)
1655                        arg = !arg;
1656                else if (unlikely(!(m->flags & MOPT_SET))) {
1657                        ext4_msg(sb, KERN_WARNING,
1658                                 "buggy handling of option %s", opt);
1659                        WARN_ON(1);
1660                        return -1;
1661                }
1662                if (arg != 0)
1663                        sbi->s_mount_opt |= m->mount_opt;
1664                else
1665                        sbi->s_mount_opt &= ~m->mount_opt;
1666        }
1667        return 1;
1668}
1669
1670static int parse_options(char *options, struct super_block *sb,
1671                         unsigned long *journal_devnum,
1672                         unsigned int *journal_ioprio,
1673                         int is_remount)
1674{
1675        struct ext4_sb_info *sbi = EXT4_SB(sb);
1676        char *p;
1677        substring_t args[MAX_OPT_ARGS];
1678        int token;
1679
1680        if (!options)
1681                return 1;
1682
1683        while ((p = strsep(&options, ",")) != NULL) {
1684                if (!*p)
1685                        continue;
1686                /*
1687                 * Initialize args struct so we know whether arg was
1688                 * found; some options take optional arguments.
1689                 */
1690                args[0].to = args[0].from = NULL;
1691                token = match_token(p, tokens, args);
1692                if (handle_mount_opt(sb, p, token, args, journal_devnum,
1693                                     journal_ioprio, is_remount) < 0)
1694                        return 0;
1695        }
1696#ifdef CONFIG_QUOTA
1697        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
1698            (test_opt(sb, USRQUOTA) || test_opt(sb, GRPQUOTA))) {
1699                ext4_msg(sb, KERN_ERR, "Cannot set quota options when QUOTA "
1700                         "feature is enabled");
1701                return 0;
1702        }
1703        if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1704                if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1705                        clear_opt(sb, USRQUOTA);
1706
1707                if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1708                        clear_opt(sb, GRPQUOTA);
1709
1710                if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1711                        ext4_msg(sb, KERN_ERR, "old and new quota "
1712                                        "format mixing");
1713                        return 0;
1714                }
1715
1716                if (!sbi->s_jquota_fmt) {
1717                        ext4_msg(sb, KERN_ERR, "journaled quota format "
1718                                        "not specified");
1719                        return 0;
1720                }
1721        }
1722#endif
1723        if (test_opt(sb, DIOREAD_NOLOCK)) {
1724                int blocksize =
1725                        BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1726
1727                if (blocksize < PAGE_CACHE_SIZE) {
1728                        ext4_msg(sb, KERN_ERR, "can't mount with "
1729                                 "dioread_nolock if block size != PAGE_SIZE");
1730                        return 0;
1731                }
1732        }
1733        if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
1734            test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
1735                ext4_msg(sb, KERN_ERR, "can't mount with journal_async_commit "
1736                         "in data=ordered mode");
1737                return 0;
1738        }
1739        return 1;
1740}
1741
1742static inline void ext4_show_quota_options(struct seq_file *seq,
1743                                           struct super_block *sb)
1744{
1745#if defined(CONFIG_QUOTA)
1746        struct ext4_sb_info *sbi = EXT4_SB(sb);
1747
1748        if (sbi->s_jquota_fmt) {
1749                char *fmtname = "";
1750
1751                switch (sbi->s_jquota_fmt) {
1752                case QFMT_VFS_OLD:
1753                        fmtname = "vfsold";
1754                        break;
1755                case QFMT_VFS_V0:
1756                        fmtname = "vfsv0";
1757                        break;
1758                case QFMT_VFS_V1:
1759                        fmtname = "vfsv1";
1760                        break;
1761                }
1762                seq_printf(seq, ",jqfmt=%s", fmtname);
1763        }
1764
1765        if (sbi->s_qf_names[USRQUOTA])
1766                seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1767
1768        if (sbi->s_qf_names[GRPQUOTA])
1769                seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1770#endif
1771}
1772
1773static const char *token2str(int token)
1774{
1775        const struct match_token *t;
1776
1777        for (t = tokens; t->token != Opt_err; t++)
1778                if (t->token == token && !strchr(t->pattern, '='))
1779                        break;
1780        return t->pattern;
1781}
1782
1783/*
1784 * Show an option if
1785 *  - it's set to a non-default value OR
1786 *  - if the per-sb default is different from the global default
1787 */
1788static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1789                              int nodefs)
1790{
1791        struct ext4_sb_info *sbi = EXT4_SB(sb);
1792        struct ext4_super_block *es = sbi->s_es;
1793        int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1794        const struct mount_opts *m;
1795        char sep = nodefs ? '\n' : ',';
1796
1797#define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1798#define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1799
1800        if (sbi->s_sb_block != 1)
1801                SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1802
1803        for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1804                int want_set = m->flags & MOPT_SET;
1805                if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1806                    (m->flags & MOPT_CLEAR_ERR))
1807                        continue;
1808                if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1809                        continue; /* skip if same as the default */
1810                if ((want_set &&
1811                     (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1812                    (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1813                        continue; /* select Opt_noFoo vs Opt_Foo */
1814                SEQ_OPTS_PRINT("%s", token2str(m->token));
1815        }
1816
1817        if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1818            le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1819                SEQ_OPTS_PRINT("resuid=%u",
1820                                from_kuid_munged(&init_user_ns, sbi->s_resuid));
1821        if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1822            le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1823                SEQ_OPTS_PRINT("resgid=%u",
1824                                from_kgid_munged(&init_user_ns, sbi->s_resgid));
1825        def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1826        if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1827                SEQ_OPTS_PUTS("errors=remount-ro");
1828        if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1829                SEQ_OPTS_PUTS("errors=continue");
1830        if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1831                SEQ_OPTS_PUTS("errors=panic");
1832        if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1833                SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1834        if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1835                SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1836        if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1837                SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1838        if (sb->s_flags & MS_I_VERSION)
1839                SEQ_OPTS_PUTS("i_version");
1840        if (nodefs || sbi->s_stripe)
1841                SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1842        if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1843                if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1844                        SEQ_OPTS_PUTS("data=journal");
1845                else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1846                        SEQ_OPTS_PUTS("data=ordered");
1847                else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1848                        SEQ_OPTS_PUTS("data=writeback");
1849        }
1850        if (nodefs ||
1851            sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1852                SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1853                               sbi->s_inode_readahead_blks);
1854
1855        if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1856                       (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1857                SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1858        if (nodefs || sbi->s_max_dir_size_kb)
1859                SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
1860
1861        ext4_show_quota_options(seq, sb);
1862        return 0;
1863}
1864
1865static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1866{
1867        return _ext4_show_options(seq, root->d_sb, 0);
1868}
1869
1870static int options_seq_show(struct seq_file *seq, void *offset)
1871{
1872        struct super_block *sb = seq->private;
1873        int rc;
1874
1875        seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1876        rc = _ext4_show_options(seq, sb, 1);
1877        seq_puts(seq, "\n");
1878        return rc;
1879}
1880
1881static int options_open_fs(struct inode *inode, struct file *file)
1882{
1883        return single_open(file, options_seq_show, PDE_DATA(inode));
1884}
1885
1886static const struct file_operations ext4_seq_options_fops = {
1887        .owner = THIS_MODULE,
1888        .open = options_open_fs,
1889        .read = seq_read,
1890        .llseek = seq_lseek,
1891        .release = single_release,
1892};
1893
1894static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1895                            int read_only)
1896{
1897        struct ext4_sb_info *sbi = EXT4_SB(sb);
1898        int res = 0;
1899
1900        if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1901                ext4_msg(sb, KERN_ERR, "revision level too high, "
1902                         "forcing read-only mode");
1903                res = MS_RDONLY;
1904        }
1905        if (read_only)
1906                goto done;
1907        if (!(sbi->s_mount_state & EXT4_VALID_FS))
1908                ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1909                         "running e2fsck is recommended");
1910        else if (sbi->s_mount_state & EXT4_ERROR_FS)
1911                ext4_msg(sb, KERN_WARNING,
1912                         "warning: mounting fs with errors, "
1913                         "running e2fsck is recommended");
1914        else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1915                 le16_to_cpu(es->s_mnt_count) >=
1916                 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1917                ext4_msg(sb, KERN_WARNING,
1918                         "warning: maximal mount count reached, "
1919                         "running e2fsck is recommended");
1920        else if (le32_to_cpu(es->s_checkinterval) &&
1921                (le32_to_cpu(es->s_lastcheck) +
1922                        le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1923                ext4_msg(sb, KERN_WARNING,
1924                         "warning: checktime reached, "
1925                         "running e2fsck is recommended");
1926        if (!sbi->s_journal)
1927                es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1928        if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1929                es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1930        le16_add_cpu(&es->s_mnt_count, 1);
1931        es->s_mtime = cpu_to_le32(get_seconds());
1932        ext4_update_dynamic_rev(sb);
1933        if (sbi->s_journal)
1934                EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1935
1936        ext4_commit_super(sb, 1);
1937done:
1938        if (test_opt(sb, DEBUG))
1939                printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1940                                "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1941                        sb->s_blocksize,
1942                        sbi->s_groups_count,
1943                        EXT4_BLOCKS_PER_GROUP(sb),
1944                        EXT4_INODES_PER_GROUP(sb),
1945                        sbi->s_mount_opt, sbi->s_mount_opt2);
1946
1947        cleancache_init_fs(sb);
1948        return res;
1949}
1950
1951int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
1952{
1953        struct ext4_sb_info *sbi = EXT4_SB(sb);
1954        struct flex_groups *new_groups;
1955        int size;
1956
1957        if (!sbi->s_log_groups_per_flex)
1958                return 0;
1959
1960        size = ext4_flex_group(sbi, ngroup - 1) + 1;
1961        if (size <= sbi->s_flex_groups_allocated)
1962                return 0;
1963
1964        size = roundup_pow_of_two(size * sizeof(struct flex_groups));
1965        new_groups = ext4_kvzalloc(size, GFP_KERNEL);
1966        if (!new_groups) {
1967                ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
1968                         size / (int) sizeof(struct flex_groups));
1969                return -ENOMEM;
1970        }
1971
1972        if (sbi->s_flex_groups) {
1973                memcpy(new_groups, sbi->s_flex_groups,
1974                       (sbi->s_flex_groups_allocated *
1975                        sizeof(struct flex_groups)));
1976                kvfree(sbi->s_flex_groups);
1977        }
1978        sbi->s_flex_groups = new_groups;
1979        sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
1980        return 0;
1981}
1982
1983static int ext4_fill_flex_info(struct super_block *sb)
1984{
1985        struct ext4_sb_info *sbi = EXT4_SB(sb);
1986        struct ext4_group_desc *gdp = NULL;
1987        ext4_group_t flex_group;
1988        int i, err;
1989
1990        sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1991        if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1992                sbi->s_log_groups_per_flex = 0;
1993                return 1;
1994        }
1995
1996        err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
1997        if (err)
1998                goto failed;
1999
2000        for (i = 0; i < sbi->s_groups_count; i++) {
2001                gdp = ext4_get_group_desc(sb, i, NULL);
2002
2003                flex_group = ext4_flex_group(sbi, i);
2004                atomic_add(ext4_free_inodes_count(sb, gdp),
2005                           &sbi->s_flex_groups[flex_group].free_inodes);
2006                atomic64_add(ext4_free_group_clusters(sb, gdp),
2007                             &sbi->s_flex_groups[flex_group].free_clusters);
2008                atomic_add(ext4_used_dirs_count(sb, gdp),
2009                           &sbi->s_flex_groups[flex_group].used_dirs);
2010        }
2011
2012        return 1;
2013failed:
2014        return 0;
2015}
2016
2017static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
2018                                   struct ext4_group_desc *gdp)
2019{
2020        int offset;
2021        __u16 crc = 0;
2022        __le32 le_group = cpu_to_le32(block_group);
2023
2024        if (ext4_has_metadata_csum(sbi->s_sb)) {
2025                /* Use new metadata_csum algorithm */
2026                __le16 save_csum;
2027                __u32 csum32;
2028
2029                save_csum = gdp->bg_checksum;
2030                gdp->bg_checksum = 0;
2031                csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2032                                     sizeof(le_group));
2033                csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
2034                                     sbi->s_desc_size);
2035                gdp->bg_checksum = save_csum;
2036
2037                crc = csum32 & 0xFFFF;
2038                goto out;
2039        }
2040
2041        /* old crc16 code */
2042        if (!(sbi->s_es->s_feature_ro_compat &
2043              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)))
2044                return 0;
2045
2046        offset = offsetof(struct ext4_group_desc, bg_checksum);
2047
2048        crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2049        crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2050        crc = crc16(crc, (__u8 *)gdp, offset);
2051        offset += sizeof(gdp->bg_checksum); /* skip checksum */
2052        /* for checksum of struct ext4_group_desc do the rest...*/
2053        if ((sbi->s_es->s_feature_incompat &
2054             cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2055            offset < le16_to_cpu(sbi->s_es->s_desc_size))
2056                crc = crc16(crc, (__u8 *)gdp + offset,
2057                            le16_to_cpu(sbi->s_es->s_desc_size) -
2058                                offset);
2059
2060out:
2061        return cpu_to_le16(crc);
2062}
2063
2064int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2065                                struct ext4_group_desc *gdp)
2066{
2067        if (ext4_has_group_desc_csum(sb) &&
2068            (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
2069                                                      block_group, gdp)))
2070                return 0;
2071
2072        return 1;
2073}
2074
2075void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2076                              struct ext4_group_desc *gdp)
2077{
2078        if (!ext4_has_group_desc_csum(sb))
2079                return;
2080        gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
2081}
2082
2083/* Called at mount-time, super-block is locked */
2084static int ext4_check_descriptors(struct super_block *sb,
2085                                  ext4_group_t *first_not_zeroed)
2086{
2087        struct ext4_sb_info *sbi = EXT4_SB(sb);
2088        ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2089        ext4_fsblk_t last_block;
2090        ext4_fsblk_t block_bitmap;
2091        ext4_fsblk_t inode_bitmap;
2092        ext4_fsblk_t inode_table;
2093        int flexbg_flag = 0;
2094        ext4_group_t i, grp = sbi->s_groups_count;
2095
2096        if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2097                flexbg_flag = 1;
2098
2099        ext4_debug("Checking group descriptors");
2100
2101        for (i = 0; i < sbi->s_groups_count; i++) {
2102                struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2103
2104                if (i == sbi->s_groups_count - 1 || flexbg_flag)
2105                        last_block = ext4_blocks_count(sbi->s_es) - 1;
2106                else
2107                        last_block = first_block +
2108                                (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2109
2110                if ((grp == sbi->s_groups_count) &&
2111                   !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2112                        grp = i;
2113
2114                block_bitmap = ext4_block_bitmap(sb, gdp);
2115                if (block_bitmap < first_block || block_bitmap > last_block) {
2116                        ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2117                               "Block bitmap for group %u not in group "
2118                               "(block %llu)!", i, block_bitmap);
2119                        return 0;
2120                }
2121                inode_bitmap = ext4_inode_bitmap(sb, gdp);
2122                if (inode_bitmap < first_block || inode_bitmap > last_block) {
2123                        ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2124                               "Inode bitmap for group %u not in group "
2125                               "(block %llu)!", i, inode_bitmap);
2126                        return 0;
2127                }
2128                inode_table = ext4_inode_table(sb, gdp);
2129                if (inode_table < first_block ||
2130                    inode_table + sbi->s_itb_per_group - 1 > last_block) {
2131                        ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2132                               "Inode table for group %u not in group "
2133                               "(block %llu)!", i, inode_table);
2134                        return 0;
2135                }
2136                ext4_lock_group(sb, i);
2137                if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2138                        ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2139                                 "Checksum for group %u failed (%u!=%u)",
2140                                 i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2141                                     gdp)), le16_to_cpu(gdp->bg_checksum));
2142                        if (!(sb->s_flags & MS_RDONLY)) {
2143                                ext4_unlock_group(sb, i);
2144                                return 0;
2145                        }
2146                }
2147                ext4_unlock_group(sb, i);
2148                if (!flexbg_flag)
2149                        first_block += EXT4_BLOCKS_PER_GROUP(sb);
2150        }
2151        if (NULL != first_not_zeroed)
2152                *first_not_zeroed = grp;
2153        return 1;
2154}
2155
2156/* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2157 * the superblock) which were deleted from all directories, but held open by
2158 * a process at the time of a crash.  We walk the list and try to delete these
2159 * inodes at recovery time (only with a read-write filesystem).
2160 *
2161 * In order to keep the orphan inode chain consistent during traversal (in
2162 * case of crash during recovery), we link each inode into the superblock
2163 * orphan list_head and handle it the same way as an inode deletion during
2164 * normal operation (which journals the operations for us).
2165 *
2166 * We only do an iget() and an iput() on each inode, which is very safe if we
2167 * accidentally point at an in-use or already deleted inode.  The worst that
2168 * can happen in this case is that we get a "bit already cleared" message from
2169 * ext4_free_inode().  The only reason we would point at a wrong inode is if
2170 * e2fsck was run on this filesystem, and it must have already done the orphan
2171 * inode cleanup for us, so we can safely abort without any further action.
2172 */
2173static void ext4_orphan_cleanup(struct super_block *sb,
2174                                struct ext4_super_block *es)
2175{
2176        unsigned int s_flags = sb->s_flags;
2177        int nr_orphans = 0, nr_truncates = 0;
2178#ifdef CONFIG_QUOTA
2179        int i;
2180#endif
2181        if (!es->s_last_orphan) {
2182                jbd_debug(4, "no orphan inodes to clean up\n");
2183                return;
2184        }
2185
2186        if (bdev_read_only(sb->s_bdev)) {
2187                ext4_msg(sb, KERN_ERR, "write access "
2188                        "unavailable, skipping orphan cleanup");
2189                return;
2190        }
2191
2192        /* Check if feature set would not allow a r/w mount */
2193        if (!ext4_feature_set_ok(sb, 0)) {
2194                ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2195                         "unknown ROCOMPAT features");
2196                return;
2197        }
2198
2199        if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2200                /* don't clear list on RO mount w/ errors */
2201                if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2202                        ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2203                                  "clearing orphan list.\n");
2204                        es->s_last_orphan = 0;
2205                }
2206                jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2207                return;
2208        }
2209
2210        if (s_flags & MS_RDONLY) {
2211                ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2212                sb->s_flags &= ~MS_RDONLY;
2213        }
2214#ifdef CONFIG_QUOTA
2215        /* Needed for iput() to work correctly and not trash data */
2216        sb->s_flags |= MS_ACTIVE;
2217        /* Turn on quotas so that they are updated correctly */
2218        for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2219                if (EXT4_SB(sb)->s_qf_names[i]) {
2220                        int ret = ext4_quota_on_mount(sb, i);
2221                        if (ret < 0)
2222                                ext4_msg(sb, KERN_ERR,
2223                                        "Cannot turn on journaled "
2224                                        "quota: error %d", ret);
2225                }
2226        }
2227#endif
2228
2229        while (es->s_last_orphan) {
2230                struct inode *inode;
2231
2232                inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2233                if (IS_ERR(inode)) {
2234                        es->s_last_orphan = 0;
2235                        break;
2236                }
2237
2238                list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2239                dquot_initialize(inode);
2240                if (inode->i_nlink) {
2241                        if (test_opt(sb, DEBUG))
2242                                ext4_msg(sb, KERN_DEBUG,
2243                                        "%s: truncating inode %lu to %lld bytes",
2244                                        __func__, inode->i_ino, inode->i_size);
2245                        jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2246                                  inode->i_ino, inode->i_size);
2247                        mutex_lock(&inode->i_mutex);
2248                        truncate_inode_pages(inode->i_mapping, inode->i_size);
2249                        ext4_truncate(inode);
2250                        mutex_unlock(&inode->i_mutex);
2251                        nr_truncates++;
2252                } else {
2253                        if (test_opt(sb, DEBUG))
2254                                ext4_msg(sb, KERN_DEBUG,
2255                                        "%s: deleting unreferenced inode %lu",
2256                                        __func__, inode->i_ino);
2257                        jbd_debug(2, "deleting unreferenced inode %lu\n",
2258                                  inode->i_ino);
2259                        nr_orphans++;
2260                }
2261                iput(inode);  /* The delete magic happens here! */
2262        }
2263
2264#define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2265
2266        if (nr_orphans)
2267                ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2268                       PLURAL(nr_orphans));
2269        if (nr_truncates)
2270                ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2271                       PLURAL(nr_truncates));
2272#ifdef CONFIG_QUOTA
2273        /* Turn quotas off */
2274        for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2275                if (sb_dqopt(sb)->files[i])
2276                        dquot_quota_off(sb, i);
2277        }
2278#endif
2279        sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2280}
2281
2282/*
2283 * Maximal extent format file size.
2284 * Resulting logical blkno at s_maxbytes must fit in our on-disk
2285 * extent format containers, within a sector_t, and within i_blocks
2286 * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2287 * so that won't be a limiting factor.
2288 *
2289 * However there is other limiting factor. We do store extents in the form
2290 * of starting block and length, hence the resulting length of the extent
2291 * covering maximum file size must fit into on-disk format containers as
2292 * well. Given that length is always by 1 unit bigger than max unit (because
2293 * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2294 *
2295 * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2296 */
2297static loff_t ext4_max_size(int blkbits, int has_huge_files)
2298{
2299        loff_t res;
2300        loff_t upper_limit = MAX_LFS_FILESIZE;
2301
2302        /* small i_blocks in vfs inode? */
2303        if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2304                /*
2305                 * CONFIG_LBDAF is not enabled implies the inode
2306                 * i_block represent total blocks in 512 bytes
2307                 * 32 == size of vfs inode i_blocks * 8
2308                 */
2309                upper_limit = (1LL << 32) - 1;
2310
2311                /* total blocks in file system block size */
2312                upper_limit >>= (blkbits - 9);
2313                upper_limit <<= blkbits;
2314        }
2315
2316        /*
2317         * 32-bit extent-start container, ee_block. We lower the maxbytes
2318         * by one fs block, so ee_len can cover the extent of maximum file
2319         * size
2320         */
2321        res = (1LL << 32) - 1;
2322        res <<= blkbits;
2323
2324        /* Sanity check against vm- & vfs- imposed limits */
2325        if (res > upper_limit)
2326                res = upper_limit;
2327
2328        return res;
2329}
2330
2331/*
2332 * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2333 * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2334 * We need to be 1 filesystem block less than the 2^48 sector limit.
2335 */
2336static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2337{
2338        loff_t res = EXT4_NDIR_BLOCKS;
2339        int meta_blocks;
2340        loff_t upper_limit;
2341        /* This is calculated to be the largest file size for a dense, block
2342         * mapped file such that the file's total number of 512-byte sectors,
2343         * including data and all indirect blocks, does not exceed (2^48 - 1).
2344         *
2345         * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2346         * number of 512-byte sectors of the file.
2347         */
2348
2349        if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2350                /*
2351                 * !has_huge_files or CONFIG_LBDAF not enabled implies that
2352                 * the inode i_block field represents total file blocks in
2353                 * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2354                 */
2355                upper_limit = (1LL << 32) - 1;
2356
2357                /* total blocks in file system block size */
2358                upper_limit >>= (bits - 9);
2359
2360        } else {
2361                /*
2362                 * We use 48 bit ext4_inode i_blocks
2363                 * With EXT4_HUGE_FILE_FL set the i_blocks
2364                 * represent total number of blocks in
2365                 * file system block size
2366                 */
2367                upper_limit = (1LL << 48) - 1;
2368
2369        }
2370
2371        /* indirect blocks */
2372        meta_blocks = 1;
2373        /* double indirect blocks */
2374        meta_blocks += 1 + (1LL << (bits-2));
2375        /* tripple indirect blocks */
2376        meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2377
2378        upper_limit -= meta_blocks;
2379        upper_limit <<= bits;
2380
2381        res += 1LL << (bits-2);
2382        res += 1LL << (2*(bits-2));
2383        res += 1LL << (3*(bits-2));
2384        res <<= bits;
2385        if (res > upper_limit)
2386                res = upper_limit;
2387
2388        if (res > MAX_LFS_FILESIZE)
2389                res = MAX_LFS_FILESIZE;
2390
2391        return res;
2392}
2393
2394static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2395                                   ext4_fsblk_t logical_sb_block, int nr)
2396{
2397        struct ext4_sb_info *sbi = EXT4_SB(sb);
2398        ext4_group_t bg, first_meta_bg;
2399        int has_super = 0;
2400
2401        first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2402
2403        if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2404            nr < first_meta_bg)
2405                return logical_sb_block + nr + 1;
2406        bg = sbi->s_desc_per_block * nr;
2407        if (ext4_bg_has_super(sb, bg))
2408                has_super = 1;
2409
2410        /*
2411         * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2412         * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2413         * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2414         * compensate.
2415         */
2416        if (sb->s_blocksize == 1024 && nr == 0 &&
2417            le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) == 0)
2418                has_super++;
2419
2420        return (has_super + ext4_group_first_block_no(sb, bg));
2421}
2422
2423/**
2424 * ext4_get_stripe_size: Get the stripe size.
2425 * @sbi: In memory super block info
2426 *
2427 * If we have specified it via mount option, then
2428 * use the mount option value. If the value specified at mount time is
2429 * greater than the blocks per group use the super block value.
2430 * If the super block value is greater than blocks per group return 0.
2431 * Allocator needs it be less than blocks per group.
2432 *
2433 */
2434static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2435{
2436        unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2437        unsigned long stripe_width =
2438                        le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2439        int ret;
2440
2441        if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2442                ret = sbi->s_stripe;
2443        else if (stripe_width <= sbi->s_blocks_per_group)
2444                ret = stripe_width;
2445        else if (stride <= sbi->s_blocks_per_group)
2446                ret = stride;
2447        else
2448                ret = 0;
2449
2450        /*
2451         * If the stripe width is 1, this makes no sense and
2452         * we set it to 0 to turn off stripe handling code.
2453         */
2454        if (ret <= 1)
2455                ret = 0;
2456
2457        return ret;
2458}
2459
2460/* sysfs supprt */
2461
2462struct ext4_attr {
2463        struct attribute attr;
2464        ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2465        ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2466                         const char *, size_t);
2467        union {
2468                int offset;
2469                int deprecated_val;
2470        } u;
2471};
2472
2473static int parse_strtoull(const char *buf,
2474                unsigned long long max, unsigned long long *value)
2475{
2476        int ret;
2477
2478        ret = kstrtoull(skip_spaces(buf), 0, value);
2479        if (!ret && *value > max)
2480                ret = -EINVAL;
2481        return ret;
2482}
2483
2484static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2485                                              struct ext4_sb_info *sbi,
2486                                              char *buf)
2487{
2488        return snprintf(buf, PAGE_SIZE, "%llu\n",
2489                (s64) EXT4_C2B(sbi,
2490                        percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2491}
2492
2493static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2494                                         struct ext4_sb_info *sbi, char *buf)
2495{
2496        struct super_block *sb = sbi->s_buddy_cache->i_sb;
2497
2498        if (!sb->s_bdev->bd_part)
2499                return snprintf(buf, PAGE_SIZE, "0\n");
2500        return snprintf(buf, PAGE_SIZE, "%lu\n",
2501                        (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2502                         sbi->s_sectors_written_start) >> 1);
2503}
2504
2505static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2506                                          struct ext4_sb_info *sbi, char *buf)
2507{
2508        struct super_block *sb = sbi->s_buddy_cache->i_sb;
2509
2510        if (!sb->s_bdev->bd_part)
2511                return snprintf(buf, PAGE_SIZE, "0\n");
2512        return snprintf(buf, PAGE_SIZE, "%llu\n",
2513                        (unsigned long long)(sbi->s_kbytes_written +
2514                        ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2515                          EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2516}
2517
2518static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2519                                          struct ext4_sb_info *sbi,
2520                                          const char *buf, size_t count)
2521{
2522        unsigned long t;
2523        int ret;
2524
2525        ret = kstrtoul(skip_spaces(buf), 0, &t);
2526        if (ret)
2527                return ret;
2528
2529        if (t && (!is_power_of_2(t) || t > 0x40000000))
2530                return -EINVAL;
2531
2532        sbi->s_inode_readahead_blks = t;
2533        return count;
2534}
2535
2536static ssize_t sbi_ui_show(struct ext4_attr *a,
2537                           struct ext4_sb_info *sbi, char *buf)
2538{
2539        unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
2540
2541        return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2542}
2543
2544static ssize_t sbi_ui_store(struct ext4_attr *a,
2545                            struct ext4_sb_info *sbi,
2546                            const char *buf, size_t count)
2547{
2548        unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
2549        unsigned long t;
2550        int ret;
2551
2552        ret = kstrtoul(skip_spaces(buf), 0, &t);
2553        if (ret)
2554                return ret;
2555        *ui = t;
2556        return count;
2557}
2558
2559static ssize_t es_ui_show(struct ext4_attr *a,
2560                           struct ext4_sb_info *sbi, char *buf)
2561{
2562
2563        unsigned int *ui = (unsigned int *) (((char *) sbi->s_es) +
2564                           a->u.offset);
2565
2566        return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2567}
2568
2569static ssize_t reserved_clusters_show(struct ext4_attr *a,
2570                                  struct ext4_sb_info *sbi, char *buf)
2571{
2572        return snprintf(buf, PAGE_SIZE, "%llu\n",
2573                (unsigned long long) atomic64_read(&sbi->s_resv_clusters));
2574}
2575
2576static ssize_t reserved_clusters_store(struct ext4_attr *a,
2577                                   struct ext4_sb_info *sbi,
2578                                   const char *buf, size_t count)
2579{
2580        unsigned long long val;
2581        int ret;
2582
2583        if (parse_strtoull(buf, -1ULL, &val))
2584                return -EINVAL;
2585        ret = ext4_reserve_clusters(sbi, val);
2586
2587        return ret ? ret : count;
2588}
2589
2590static ssize_t trigger_test_error(struct ext4_attr *a,
2591                                  struct ext4_sb_info *sbi,
2592                                  const char *buf, size_t count)
2593{
2594        int len = count;
2595
2596        if (!capable(CAP_SYS_ADMIN))
2597                return -EPERM;
2598
2599        if (len && buf[len-1] == '\n')
2600                len--;
2601
2602        if (len)
2603                ext4_error(sbi->s_sb, "%.*s", len, buf);
2604        return count;
2605}
2606
2607static ssize_t sbi_deprecated_show(struct ext4_attr *a,
2608                                   struct ext4_sb_info *sbi, char *buf)
2609{
2610        return snprintf(buf, PAGE_SIZE, "%d\n", a->u.deprecated_val);
2611}
2612
2613#define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2614static struct ext4_attr ext4_attr_##_name = {                   \
2615        .attr = {.name = __stringify(_name), .mode = _mode },   \
2616        .show   = _show,                                        \
2617        .store  = _store,                                       \
2618        .u = {                                                  \
2619                .offset = offsetof(struct ext4_sb_info, _elname),\
2620        },                                                      \
2621}
2622
2623#define EXT4_ATTR_OFFSET_ES(_name,_mode,_show,_store,_elname)           \
2624static struct ext4_attr ext4_attr_##_name = {                           \
2625        .attr = {.name = __stringify(_name), .mode = _mode },           \
2626        .show   = _show,                                                \
2627        .store  = _store,                                               \
2628        .u = {                                                          \
2629                .offset = offsetof(struct ext4_super_block, _elname),   \
2630        },                                                              \
2631}
2632
2633#define EXT4_ATTR(name, mode, show, store) \
2634static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2635
2636#define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2637#define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2638#define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2639
2640#define EXT4_RO_ATTR_ES_UI(name, elname)        \
2641        EXT4_ATTR_OFFSET_ES(name, 0444, es_ui_show, NULL, elname)
2642#define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2643        EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2644
2645#define ATTR_LIST(name) &ext4_attr_##name.attr
2646#define EXT4_DEPRECATED_ATTR(_name, _val)       \
2647static struct ext4_attr ext4_attr_##_name = {                   \
2648        .attr = {.name = __stringify(_name), .mode = 0444 },    \
2649        .show   = sbi_deprecated_show,                          \
2650        .u = {                                                  \
2651                .deprecated_val = _val,                         \
2652        },                                                      \
2653}
2654
2655EXT4_RO_ATTR(delayed_allocation_blocks);
2656EXT4_RO_ATTR(session_write_kbytes);
2657EXT4_RO_ATTR(lifetime_write_kbytes);
2658EXT4_RW_ATTR(reserved_clusters);
2659EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2660                 inode_readahead_blks_store, s_inode_readahead_blks);
2661EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2662EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2663EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2664EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2665EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2666EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2667EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2668EXT4_DEPRECATED_ATTR(max_writeback_mb_bump, 128);
2669EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
2670EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error);
2671EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
2672EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst);
2673EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
2674EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
2675EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
2676EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
2677EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
2678EXT4_RO_ATTR_ES_UI(first_error_time, s_first_error_time);
2679EXT4_RO_ATTR_ES_UI(last_error_time, s_last_error_time);
2680
2681static struct attribute *ext4_attrs[] = {
2682        ATTR_LIST(delayed_allocation_blocks),
2683        ATTR_LIST(session_write_kbytes),
2684        ATTR_LIST(lifetime_write_kbytes),
2685        ATTR_LIST(reserved_clusters),
2686        ATTR_LIST(inode_readahead_blks),
2687        ATTR_LIST(inode_goal),
2688        ATTR_LIST(mb_stats),
2689        ATTR_LIST(mb_max_to_scan),
2690        ATTR_LIST(mb_min_to_scan),
2691        ATTR_LIST(mb_order2_req),
2692        ATTR_LIST(mb_stream_req),
2693        ATTR_LIST(mb_group_prealloc),
2694        ATTR_LIST(max_writeback_mb_bump),
2695        ATTR_LIST(extent_max_zeroout_kb),
2696        ATTR_LIST(trigger_fs_error),
2697        ATTR_LIST(err_ratelimit_interval_ms),
2698        ATTR_LIST(err_ratelimit_burst),
2699        ATTR_LIST(warning_ratelimit_interval_ms),
2700        ATTR_LIST(warning_ratelimit_burst),
2701        ATTR_LIST(msg_ratelimit_interval_ms),
2702        ATTR_LIST(msg_ratelimit_burst),
2703        ATTR_LIST(errors_count),
2704        ATTR_LIST(first_error_time),
2705        ATTR_LIST(last_error_time),
2706        NULL,
2707};
2708
2709/* Features this copy of ext4 supports */
2710EXT4_INFO_ATTR(lazy_itable_init);
2711EXT4_INFO_ATTR(batched_discard);
2712EXT4_INFO_ATTR(meta_bg_resize);
2713EXT4_INFO_ATTR(encryption);
2714
2715static struct attribute *ext4_feat_attrs[] = {
2716        ATTR_LIST(lazy_itable_init),
2717        ATTR_LIST(batched_discard),
2718        ATTR_LIST(meta_bg_resize),
2719        ATTR_LIST(encryption),
2720        NULL,
2721};
2722
2723static ssize_t ext4_attr_show(struct kobject *kobj,
2724                              struct attribute *attr, char *buf)
2725{
2726        struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2727                                                s_kobj);
2728        struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2729
2730        return a->show ? a->show(a, sbi, buf) : 0;
2731}
2732
2733static ssize_t ext4_attr_store(struct kobject *kobj,
2734                               struct attribute *attr,
2735                               const char *buf, size_t len)
2736{
2737        struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2738                                                s_kobj);
2739        struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2740
2741        return a->store ? a->store(a, sbi, buf, len) : 0;
2742}
2743
2744static void ext4_sb_release(struct kobject *kobj)
2745{
2746        struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2747                                                s_kobj);
2748        complete(&sbi->s_kobj_unregister);
2749}
2750
2751static const struct sysfs_ops ext4_attr_ops = {
2752        .show   = ext4_attr_show,
2753        .store  = ext4_attr_store,
2754};
2755
2756static struct kobj_type ext4_ktype = {
2757        .default_attrs  = ext4_attrs,
2758        .sysfs_ops      = &ext4_attr_ops,
2759        .release        = ext4_sb_release,
2760};
2761
2762static void ext4_feat_release(struct kobject *kobj)
2763{
2764        complete(&ext4_feat->f_kobj_unregister);
2765}
2766
2767static ssize_t ext4_feat_show(struct kobject *kobj,
2768                              struct attribute *attr, char *buf)
2769{
2770        return snprintf(buf, PAGE_SIZE, "supported\n");
2771}
2772
2773/*
2774 * We can not use ext4_attr_show/store because it relies on the kobject
2775 * being embedded in the ext4_sb_info structure which is definitely not
2776 * true in this case.
2777 */
2778static const struct sysfs_ops ext4_feat_ops = {
2779        .show   = ext4_feat_show,
2780        .store  = NULL,
2781};
2782
2783static struct kobj_type ext4_feat_ktype = {
2784        .default_attrs  = ext4_feat_attrs,
2785        .sysfs_ops      = &ext4_feat_ops,
2786        .release        = ext4_feat_release,
2787};
2788
2789/*
2790 * Check whether this filesystem can be mounted based on
2791 * the features present and the RDONLY/RDWR mount requested.
2792 * Returns 1 if this filesystem can be mounted as requested,
2793 * 0 if it cannot be.
2794 */
2795static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2796{
2797        if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2798                ext4_msg(sb, KERN_ERR,
2799                        "Couldn't mount because of "
2800                        "unsupported optional features (%x)",
2801                        (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2802                        ~EXT4_FEATURE_INCOMPAT_SUPP));
2803                return 0;
2804        }
2805
2806        if (readonly)
2807                return 1;
2808
2809        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_READONLY)) {
2810                ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2811                sb->s_flags |= MS_RDONLY;
2812                return 1;
2813        }
2814
2815        /* Check that feature set is OK for a read-write mount */
2816        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2817                ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2818                         "unsupported optional features (%x)",
2819                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2820                                ~EXT4_FEATURE_RO_COMPAT_SUPP));
2821                return 0;
2822        }
2823        /*
2824         * Large file size enabled file system can only be mounted
2825         * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2826         */
2827        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2828                if (sizeof(blkcnt_t) < sizeof(u64)) {
2829                        ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2830                                 "cannot be mounted RDWR without "
2831                                 "CONFIG_LBDAF");
2832                        return 0;
2833                }
2834        }
2835        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2836            !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2837                ext4_msg(sb, KERN_ERR,
2838                         "Can't support bigalloc feature without "
2839                         "extents feature\n");
2840                return 0;
2841        }
2842
2843#ifndef CONFIG_QUOTA
2844        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
2845            !readonly) {
2846                ext4_msg(sb, KERN_ERR,
2847                         "Filesystem with quota feature cannot be mounted RDWR "
2848                         "without CONFIG_QUOTA");
2849                return 0;
2850        }
2851#endif  /* CONFIG_QUOTA */
2852        return 1;
2853}
2854
2855/*
2856 * This function is called once a day if we have errors logged
2857 * on the file system
2858 */
2859static void print_daily_error_info(unsigned long arg)
2860{
2861        struct super_block *sb = (struct super_block *) arg;
2862        struct ext4_sb_info *sbi;
2863        struct ext4_super_block *es;
2864
2865        sbi = EXT4_SB(sb);
2866        es = sbi->s_es;
2867
2868        if (es->s_error_count)
2869                /* fsck newer than v1.41.13 is needed to clean this condition. */
2870                ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2871                         le32_to_cpu(es->s_error_count));
2872        if (es->s_first_error_time) {
2873                printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2874                       sb->s_id, le32_to_cpu(es->s_first_error_time),
2875                       (int) sizeof(es->s_first_error_func),
2876                       es->s_first_error_func,
2877                       le32_to_cpu(es->s_first_error_line));
2878                if (es->s_first_error_ino)
2879                        printk(": inode %u",
2880                               le32_to_cpu(es->s_first_error_ino));
2881                if (es->s_first_error_block)
2882                        printk(": block %llu", (unsigned long long)
2883                               le64_to_cpu(es->s_first_error_block));
2884                printk("\n");
2885        }
2886        if (es->s_last_error_time) {
2887                printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2888                       sb->s_id, le32_to_cpu(es->s_last_error_time),
2889                       (int) sizeof(es->s_last_error_func),
2890                       es->s_last_error_func,
2891                       le32_to_cpu(es->s_last_error_line));
2892                if (es->s_last_error_ino)
2893                        printk(": inode %u",
2894                               le32_to_cpu(es->s_last_error_ino));
2895                if (es->s_last_error_block)
2896                        printk(": block %llu", (unsigned long long)
2897                               le64_to_cpu(es->s_last_error_block));
2898                printk("\n");
2899        }
2900        mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2901}
2902
2903/* Find next suitable group and run ext4_init_inode_table */
2904static int ext4_run_li_request(struct ext4_li_request *elr)
2905{
2906        struct ext4_group_desc *gdp = NULL;
2907        ext4_group_t group, ngroups;
2908        struct super_block *sb;
2909        unsigned long timeout = 0;
2910        int ret = 0;
2911
2912        sb = elr->lr_super;
2913        ngroups = EXT4_SB(sb)->s_groups_count;
2914
2915        sb_start_write(sb);
2916        for (group = elr->lr_next_group; group < ngroups; group++) {
2917                gdp = ext4_get_group_desc(sb, group, NULL);
2918                if (!gdp) {
2919                        ret = 1;
2920                        break;
2921                }
2922
2923                if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2924                        break;
2925        }
2926
2927        if (group >= ngroups)
2928                ret = 1;
2929
2930        if (!ret) {
2931                timeout = jiffies;
2932                ret = ext4_init_inode_table(sb, group,
2933                                            elr->lr_timeout ? 0 : 1);
2934                if (elr->lr_timeout == 0) {
2935                        timeout = (jiffies - timeout) *
2936                                  elr->lr_sbi->s_li_wait_mult;
2937                        elr->lr_timeout = timeout;
2938                }
2939                elr->lr_next_sched = jiffies + elr->lr_timeout;
2940                elr->lr_next_group = group + 1;
2941        }
2942        sb_end_write(sb);
2943
2944        return ret;
2945}
2946
2947/*
2948 * Remove lr_request from the list_request and free the
2949 * request structure. Should be called with li_list_mtx held
2950 */
2951static void ext4_remove_li_request(struct ext4_li_request *elr)
2952{
2953        struct ext4_sb_info *sbi;
2954
2955        if (!elr)
2956                return;
2957
2958        sbi = elr->lr_sbi;
2959
2960        list_del(&elr->lr_request);
2961        sbi->s_li_request = NULL;
2962        kfree(elr);
2963}
2964
2965static void ext4_unregister_li_request(struct super_block *sb)
2966{
2967        mutex_lock(&ext4_li_mtx);
2968        if (!ext4_li_info) {
2969                mutex_unlock(&ext4_li_mtx);
2970                return;
2971        }
2972
2973        mutex_lock(&ext4_li_info->li_list_mtx);
2974        ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2975        mutex_unlock(&ext4_li_info->li_list_mtx);
2976        mutex_unlock(&ext4_li_mtx);
2977}
2978
2979static struct task_struct *ext4_lazyinit_task;
2980
2981/*
2982 * This is the function where ext4lazyinit thread lives. It walks
2983 * through the request list searching for next scheduled filesystem.
2984 * When such a fs is found, run the lazy initialization request
2985 * (ext4_rn_li_request) and keep track of the time spend in this
2986 * function. Based on that time we compute next schedule time of
2987 * the request. When walking through the list is complete, compute
2988 * next waking time and put itself into sleep.
2989 */
2990static int ext4_lazyinit_thread(void *arg)
2991{
2992        struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2993        struct list_head *pos, *n;
2994        struct ext4_li_request *elr;
2995        unsigned long next_wakeup, cur;
2996
2997        BUG_ON(NULL == eli);
2998
2999cont_thread:
3000        while (true) {
3001                next_wakeup = MAX_JIFFY_OFFSET;
3002
3003                mutex_lock(&eli->li_list_mtx);
3004                if (list_empty(&eli->li_request_list)) {
3005                        mutex_unlock(&eli->li_list_mtx);
3006                        goto exit_thread;
3007                }
3008
3009                list_for_each_safe(pos, n, &eli->li_request_list) {
3010                        elr = list_entry(pos, struct ext4_li_request,
3011                                         lr_request);
3012
3013                        if (time_after_eq(jiffies, elr->lr_next_sched)) {
3014                                if (ext4_run_li_request(elr) != 0) {
3015                                        /* error, remove the lazy_init job */
3016                                        ext4_remove_li_request(elr);
3017                                        continue;
3018                                }
3019                        }
3020
3021                        if (time_before(elr->lr_next_sched, next_wakeup))
3022                                next_wakeup = elr->lr_next_sched;
3023                }
3024                mutex_unlock(&eli->li_list_mtx);
3025
3026                try_to_freeze();
3027
3028                cur = jiffies;
3029                if ((time_after_eq(cur, next_wakeup)) ||
3030                    (MAX_JIFFY_OFFSET == next_wakeup)) {
3031                        cond_resched();
3032                        continue;
3033                }
3034
3035                schedule_timeout_interruptible(next_wakeup - cur);
3036
3037                if (kthread_should_stop()) {
3038                        ext4_clear_request_list();
3039                        goto exit_thread;
3040                }
3041        }
3042
3043exit_thread:
3044        /*
3045         * It looks like the request list is empty, but we need
3046         * to check it under the li_list_mtx lock, to prevent any
3047         * additions into it, and of course we should lock ext4_li_mtx
3048         * to atomically free the list and ext4_li_info, because at
3049         * this point another ext4 filesystem could be registering
3050         * new one.
3051         */
3052        mutex_lock(&ext4_li_mtx);
3053        mutex_lock(&eli->li_list_mtx);
3054        if (!list_empty(&eli->li_request_list)) {
3055                mutex_unlock(&eli->li_list_mtx);
3056                mutex_unlock(&ext4_li_mtx);
3057                goto cont_thread;
3058        }
3059        mutex_unlock(&eli->li_list_mtx);
3060        kfree(ext4_li_info);
3061        ext4_li_info = NULL;
3062        mutex_unlock(&ext4_li_mtx);
3063
3064        return 0;
3065}
3066
3067static void ext4_clear_request_list(void)
3068{
3069        struct list_head *pos, *n;
3070        struct ext4_li_request *elr;
3071
3072        mutex_lock(&ext4_li_info->li_list_mtx);
3073        list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3074                elr = list_entry(pos, struct ext4_li_request,
3075                                 lr_request);
3076                ext4_remove_li_request(elr);
3077        }
3078        mutex_unlock(&ext4_li_info->li_list_mtx);
3079}
3080
3081static int ext4_run_lazyinit_thread(void)
3082{
3083        ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3084                                         ext4_li_info, "ext4lazyinit");
3085        if (IS_ERR(ext4_lazyinit_task)) {
3086                int err = PTR_ERR(ext4_lazyinit_task);
3087                ext4_clear_request_list();
3088                kfree(ext4_li_info);
3089                ext4_li_info = NULL;
3090                printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3091                                 "initialization thread\n",
3092                                 err);
3093                return err;
3094        }
3095        ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3096        return 0;
3097}
3098
3099/*
3100 * Check whether it make sense to run itable init. thread or not.
3101 * If there is at least one uninitialized inode table, return
3102 * corresponding group number, else the loop goes through all
3103 * groups and return total number of groups.
3104 */
3105static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3106{
3107        ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3108        struct ext4_group_desc *gdp = NULL;
3109
3110        for (group = 0; group < ngroups; group++) {
3111                gdp = ext4_get_group_desc(sb, group, NULL);
3112                if (!gdp)
3113                        continue;
3114
3115                if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3116                        break;
3117        }
3118
3119        return group;
3120}
3121
3122static int ext4_li_info_new(void)
3123{
3124        struct ext4_lazy_init *eli = NULL;
3125
3126        eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3127        if (!eli)
3128                return -ENOMEM;
3129
3130        INIT_LIST_HEAD(&eli->li_request_list);
3131        mutex_init(&eli->li_list_mtx);
3132
3133        eli->li_state |= EXT4_LAZYINIT_QUIT;
3134
3135        ext4_li_info = eli;
3136
3137        return 0;
3138}
3139
3140static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3141                                            ext4_group_t start)
3142{
3143        struct ext4_sb_info *sbi = EXT4_SB(sb);
3144        struct ext4_li_request *elr;
3145
3146        elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3147        if (!elr)
3148                return NULL;
3149
3150        elr->lr_super = sb;
3151        elr->lr_sbi = sbi;
3152        elr->lr_next_group = start;
3153
3154        /*
3155         * Randomize first schedule time of the request to
3156         * spread the inode table initialization requests
3157         * better.
3158         */
3159        elr->lr_next_sched = jiffies + (prandom_u32() %
3160                                (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3161        return elr;
3162}
3163
3164int ext4_register_li_request(struct super_block *sb,
3165                             ext4_group_t first_not_zeroed)
3166{
3167        struct ext4_sb_info *sbi = EXT4_SB(sb);
3168        struct ext4_li_request *elr = NULL;
3169        ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3170        int ret = 0;
3171
3172        mutex_lock(&ext4_li_mtx);
3173        if (sbi->s_li_request != NULL) {
3174                /*
3175                 * Reset timeout so it can be computed again, because
3176                 * s_li_wait_mult might have changed.
3177                 */
3178                sbi->s_li_request->lr_timeout = 0;
3179                goto out;
3180        }
3181
3182        if (first_not_zeroed == ngroups ||
3183            (sb->s_flags & MS_RDONLY) ||
3184            !test_opt(sb, INIT_INODE_TABLE))
3185                goto out;
3186
3187        elr = ext4_li_request_new(sb, first_not_zeroed);
3188        if (!elr) {
3189                ret = -ENOMEM;
3190                goto out;
3191        }
3192
3193        if (NULL == ext4_li_info) {
3194                ret = ext4_li_info_new();
3195                if (ret)
3196                        goto out;
3197        }
3198
3199        mutex_lock(&ext4_li_info->li_list_mtx);
3200        list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3201        mutex_unlock(&ext4_li_info->li_list_mtx);
3202
3203        sbi->s_li_request = elr;
3204        /*
3205         * set elr to NULL here since it has been inserted to
3206         * the request_list and the removal and free of it is
3207         * handled by ext4_clear_request_list from now on.
3208         */
3209        elr = NULL;
3210
3211        if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3212                ret = ext4_run_lazyinit_thread();
3213                if (ret)
3214                        goto out;
3215        }
3216out:
3217        mutex_unlock(&ext4_li_mtx);
3218        if (ret)
3219                kfree(elr);
3220        return ret;
3221}
3222
3223/*
3224 * We do not need to lock anything since this is called on
3225 * module unload.
3226 */
3227static void ext4_destroy_lazyinit_thread(void)
3228{
3229        /*
3230         * If thread exited earlier
3231         * there's nothing to be done.
3232         */
3233        if (!ext4_li_info || !ext4_lazyinit_task)
3234                return;
3235
3236        kthread_stop(ext4_lazyinit_task);
3237}
3238
3239static int set_journal_csum_feature_set(struct super_block *sb)
3240{
3241        int ret = 1;
3242        int compat, incompat;
3243        struct ext4_sb_info *sbi = EXT4_SB(sb);
3244
3245        if (ext4_has_metadata_csum(sb)) {
3246                /* journal checksum v3 */
3247                compat = 0;
3248                incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3249        } else {
3250                /* journal checksum v1 */
3251                compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3252                incompat = 0;
3253        }
3254
3255        jbd2_journal_clear_features(sbi->s_journal,
3256                        JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3257                        JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3258                        JBD2_FEATURE_INCOMPAT_CSUM_V2);
3259        if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3260                ret = jbd2_journal_set_features(sbi->s_journal,
3261                                compat, 0,
3262                                JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3263                                incompat);
3264        } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3265                ret = jbd2_journal_set_features(sbi->s_journal,
3266                                compat, 0,
3267                                incompat);
3268                jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3269                                JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3270        } else {
3271                jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3272                                JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3273        }
3274
3275        return ret;
3276}
3277
3278/*
3279 * Note: calculating the overhead so we can be compatible with
3280 * historical BSD practice is quite difficult in the face of
3281 * clusters/bigalloc.  This is because multiple metadata blocks from
3282 * different block group can end up in the same allocation cluster.
3283 * Calculating the exact overhead in the face of clustered allocation
3284 * requires either O(all block bitmaps) in memory or O(number of block
3285 * groups**2) in time.  We will still calculate the superblock for
3286 * older file systems --- and if we come across with a bigalloc file
3287 * system with zero in s_overhead_clusters the estimate will be close to
3288 * correct especially for very large cluster sizes --- but for newer
3289 * file systems, it's better to calculate this figure once at mkfs
3290 * time, and store it in the superblock.  If the superblock value is
3291 * present (even for non-bigalloc file systems), we will use it.
3292 */
3293static int count_overhead(struct super_block *sb, ext4_group_t grp,
3294                          char *buf)
3295{
3296        struct ext4_sb_info     *sbi = EXT4_SB(sb);
3297        struct ext4_group_desc  *gdp;
3298        ext4_fsblk_t            first_block, last_block, b;
3299        ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3300        int                     s, j, count = 0;
3301
3302        if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC))
3303                return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3304                        sbi->s_itb_per_group + 2);
3305
3306        first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3307                (grp * EXT4_BLOCKS_PER_GROUP(sb));
3308        last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3309        for (i = 0; i < ngroups; i++) {
3310                gdp = ext4_get_group_desc(sb, i, NULL);
3311                b = ext4_block_bitmap(sb, gdp);
3312                if (b >= first_block && b <= last_block) {
3313                        ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3314                        count++;
3315                }
3316                b = ext4_inode_bitmap(sb, gdp);
3317                if (b >= first_block && b <= last_block) {
3318                        ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3319                        count++;
3320                }
3321                b = ext4_inode_table(sb, gdp);
3322                if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3323                        for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3324                                int c = EXT4_B2C(sbi, b - first_block);
3325                                ext4_set_bit(c, buf);
3326                                count++;
3327                        }
3328                if (i != grp)
3329                        continue;
3330                s = 0;
3331                if (ext4_bg_has_super(sb, grp)) {
3332                        ext4_set_bit(s++, buf);
3333                        count++;
3334                }
3335                for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3336                        ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3337                        count++;
3338                }
3339        }
3340        if (!count)
3341                return 0;
3342        return EXT4_CLUSTERS_PER_GROUP(sb) -
3343                ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3344}
3345
3346/*
3347 * Compute the overhead and stash it in sbi->s_overhead
3348 */
3349int ext4_calculate_overhead(struct super_block *sb)
3350{
3351        struct ext4_sb_info *sbi = EXT4_SB(sb);
3352        struct ext4_super_block *es = sbi->s_es;
3353        ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3354        ext4_fsblk_t overhead = 0;
3355        char *buf = (char *) get_zeroed_page(GFP_NOFS);
3356
3357        if (!buf)
3358                return -ENOMEM;
3359
3360        /*
3361         * Compute the overhead (FS structures).  This is constant
3362         * for a given filesystem unless the number of block groups
3363         * changes so we cache the previous value until it does.
3364         */
3365
3366        /*
3367         * All of the blocks before first_data_block are overhead
3368         */
3369        overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3370
3371        /*
3372         * Add the overhead found in each block group
3373         */
3374        for (i = 0; i < ngroups; i++) {
3375                int blks;
3376
3377                blks = count_overhead(sb, i, buf);
3378                overhead += blks;
3379                if (blks)
3380                        memset(buf, 0, PAGE_SIZE);
3381                cond_resched();
3382        }
3383        /* Add the internal journal blocks as well */
3384        if (sbi->s_journal && !sbi->journal_bdev)
3385                overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3386
3387        sbi->s_overhead = overhead;
3388        smp_wmb();
3389        free_page((unsigned long) buf);
3390        return 0;
3391}
3392
3393
3394static ext4_fsblk_t ext4_calculate_resv_clusters(struct super_block *sb)
3395{
3396        ext4_fsblk_t resv_clusters;
3397
3398        /*
3399         * There's no need to reserve anything when we aren't using extents.
3400         * The space estimates are exact, there are no unwritten extents,
3401         * hole punching doesn't need new metadata... This is needed especially
3402         * to keep ext2/3 backward compatibility.
3403         */
3404        if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS))
3405                return 0;
3406        /*
3407         * By default we reserve 2% or 4096 clusters, whichever is smaller.
3408         * This should cover the situations where we can not afford to run
3409         * out of space like for example punch hole, or converting
3410         * unwritten extents in delalloc path. In most cases such
3411         * allocation would require 1, or 2 blocks, higher numbers are
3412         * very rare.
3413         */
3414        resv_clusters = ext4_blocks_count(EXT4_SB(sb)->s_es) >>
3415                        EXT4_SB(sb)->s_cluster_bits;
3416
3417        do_div(resv_clusters, 50);
3418        resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3419
3420        return resv_clusters;
3421}
3422
3423
3424static int ext4_reserve_clusters(struct ext4_sb_info *sbi, ext4_fsblk_t count)
3425{
3426        ext4_fsblk_t clusters = ext4_blocks_count(sbi->s_es) >>
3427                                sbi->s_cluster_bits;
3428
3429        if (count >= clusters)
3430                return -EINVAL;
3431
3432        atomic64_set(&sbi->s_resv_clusters, count);
3433        return 0;
3434}
3435
3436static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3437{
3438        char *orig_data = kstrdup(data, GFP_KERNEL);
3439        struct buffer_head *bh;
3440        struct ext4_super_block *es = NULL;
3441        struct ext4_sb_info *sbi;
3442        ext4_fsblk_t block;
3443        ext4_fsblk_t sb_block = get_sb_block(&data);
3444        ext4_fsblk_t logical_sb_block;
3445        unsigned long offset = 0;
3446        unsigned long journal_devnum = 0;
3447        unsigned long def_mount_opts;
3448        struct inode *root;
3449        const char *descr;
3450        int ret = -ENOMEM;
3451        int blocksize, clustersize;
3452        unsigned int db_count;
3453        unsigned int i;
3454        int needs_recovery, has_huge_files, has_bigalloc;
3455        __u64 blocks_count;
3456        int err = 0;
3457        unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3458        ext4_group_t first_not_zeroed;
3459
3460        sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3461        if (!sbi)
3462                goto out_free_orig;
3463
3464        sbi->s_blockgroup_lock =
3465                kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3466        if (!sbi->s_blockgroup_lock) {
3467                kfree(sbi);
3468                goto out_free_orig;
3469        }
3470        sb->s_fs_info = sbi;
3471        sbi->s_sb = sb;
3472        sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3473        sbi->s_sb_block = sb_block;
3474        if (sb->s_bdev->bd_part)
3475                sbi->s_sectors_written_start =
3476                        part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3477
3478        /* Cleanup superblock name */
3479        strreplace(sb->s_id, '/', '!');
3480
3481        /* -EINVAL is default */
3482        ret = -EINVAL;
3483        blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3484        if (!blocksize) {
3485                ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3486                goto out_fail;
3487        }
3488
3489        /*
3490         * The ext4 superblock will not be buffer aligned for other than 1kB
3491         * block sizes.  We need to calculate the offset from buffer start.
3492         */
3493        if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3494                logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3495                offset = do_div(logical_sb_block, blocksize);
3496        } else {
3497                logical_sb_block = sb_block;
3498        }
3499
3500        if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3501                ext4_msg(sb, KERN_ERR, "unable to read superblock");
3502                goto out_fail;
3503        }
3504        /*
3505         * Note: s_es must be initialized as soon as possible because
3506         *       some ext4 macro-instructions depend on its value
3507         */
3508        es = (struct ext4_super_block *) (bh->b_data + offset);
3509        sbi->s_es = es;
3510        sb->s_magic = le16_to_cpu(es->s_magic);
3511        if (sb->s_magic != EXT4_SUPER_MAGIC)
3512                goto cantfind_ext4;
3513        sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3514
3515        /* Warn if metadata_csum and gdt_csum are both set. */
3516        if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3517                                       EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
3518            EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
3519                ext4_warning(sb, "metadata_csum and uninit_bg are "
3520                             "redundant flags; please run fsck.");
3521
3522        /* Check for a known checksum algorithm */
3523        if (!ext4_verify_csum_type(sb, es)) {
3524                ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3525                         "unknown checksum algorithm.");
3526                silent = 1;
3527                goto cantfind_ext4;
3528        }
3529
3530        /* Load the checksum driver */
3531        if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3532                                       EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3533                sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3534                if (IS_ERR(sbi->s_chksum_driver)) {
3535                        ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3536                        ret = PTR_ERR(sbi->s_chksum_driver);
3537                        sbi->s_chksum_driver = NULL;
3538                        goto failed_mount;
3539                }
3540        }
3541
3542        /* Check superblock checksum */
3543        if (!ext4_superblock_csum_verify(sb, es)) {
3544                ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3545                         "invalid superblock checksum.  Run e2fsck?");
3546                silent = 1;
3547                goto cantfind_ext4;
3548        }
3549
3550        /* Precompute checksum seed for all metadata */
3551        if (ext4_has_metadata_csum(sb))
3552                sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3553                                               sizeof(es->s_uuid));
3554
3555        /* Set defaults before we parse the mount options */
3556        def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3557        set_opt(sb, INIT_INODE_TABLE);
3558        if (def_mount_opts & EXT4_DEFM_DEBUG)
3559                set_opt(sb, DEBUG);
3560        if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3561                set_opt(sb, GRPID);
3562        if (def_mount_opts & EXT4_DEFM_UID16)
3563                set_opt(sb, NO_UID32);
3564        /* xattr user namespace & acls are now defaulted on */
3565        set_opt(sb, XATTR_USER);
3566#ifdef CONFIG_EXT4_FS_POSIX_ACL
3567        set_opt(sb, POSIX_ACL);
3568#endif
3569        /* don't forget to enable journal_csum when metadata_csum is enabled. */
3570        if (ext4_has_metadata_csum(sb))
3571                set_opt(sb, JOURNAL_CHECKSUM);
3572
3573        if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3574                set_opt(sb, JOURNAL_DATA);
3575        else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3576                set_opt(sb, ORDERED_DATA);
3577        else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3578                set_opt(sb, WRITEBACK_DATA);
3579
3580        if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3581                set_opt(sb, ERRORS_PANIC);
3582        else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3583                set_opt(sb, ERRORS_CONT);
3584        else
3585                set_opt(sb, ERRORS_RO);
3586        /* block_validity enabled by default; disable with noblock_validity */
3587        set_opt(sb, BLOCK_VALIDITY);
3588        if (def_mount_opts & EXT4_DEFM_DISCARD)
3589                set_opt(sb, DISCARD);
3590
3591        sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3592        sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3593        sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3594        sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3595        sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3596
3597        if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3598                set_opt(sb, BARRIER);
3599
3600        /*
3601         * enable delayed allocation by default
3602         * Use -o nodelalloc to turn it off
3603         */
3604        if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3605            ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3606                set_opt(sb, DELALLOC);
3607
3608        /*
3609         * set default s_li_wait_mult for lazyinit, for the case there is
3610         * no mount option specified.
3611         */
3612        sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3613
3614        if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3615                           &journal_devnum, &journal_ioprio, 0)) {
3616                ext4_msg(sb, KERN_WARNING,
3617                         "failed to parse options in superblock: %s",
3618                         sbi->s_es->s_mount_opts);
3619        }
3620        sbi->s_def_mount_opt = sbi->s_mount_opt;
3621        if (!parse_options((char *) data, sb, &journal_devnum,
3622                           &journal_ioprio, 0))
3623                goto failed_mount;
3624
3625        if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3626                printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3627                            "with data=journal disables delayed "
3628                            "allocation and O_DIRECT support!\n");
3629                if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3630                        ext4_msg(sb, KERN_ERR, "can't mount with "
3631                                 "both data=journal and delalloc");
3632                        goto failed_mount;
3633                }
3634                if (test_opt(sb, DIOREAD_NOLOCK)) {
3635                        ext4_msg(sb, KERN_ERR, "can't mount with "
3636                                 "both data=journal and dioread_nolock");
3637                        goto failed_mount;
3638                }
3639                if (test_opt(sb, DAX)) {
3640                        ext4_msg(sb, KERN_ERR, "can't mount with "
3641                                 "both data=journal and dax");
3642                        goto failed_mount;
3643                }
3644                if (test_opt(sb, DELALLOC))
3645                        clear_opt(sb, DELALLOC);
3646        }
3647
3648        sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3649                (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3650
3651        if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3652            (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3653             EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3654             EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3655                ext4_msg(sb, KERN_WARNING,
3656                       "feature flags set on rev 0 fs, "
3657                       "running e2fsck is recommended");
3658
3659        if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3660                set_opt2(sb, HURD_COMPAT);
3661                if (EXT4_HAS_INCOMPAT_FEATURE(sb,
3662                                              EXT4_FEATURE_INCOMPAT_64BIT)) {
3663                        ext4_msg(sb, KERN_ERR,
3664                                 "The Hurd can't support 64-bit file systems");
3665                        goto failed_mount;
3666                }
3667        }
3668
3669        if (IS_EXT2_SB(sb)) {
3670                if (ext2_feature_set_ok(sb))
3671                        ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3672                                 "using the ext4 subsystem");
3673                else {
3674                        ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3675                                 "to feature incompatibilities");
3676                        goto failed_mount;
3677                }
3678        }
3679
3680        if (IS_EXT3_SB(sb)) {
3681                if (ext3_feature_set_ok(sb))
3682                        ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3683                                 "using the ext4 subsystem");
3684                else {
3685                        ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3686                                 "to feature incompatibilities");
3687                        goto failed_mount;
3688                }
3689        }
3690
3691        /*
3692         * Check feature flags regardless of the revision level, since we
3693         * previously didn't change the revision level when setting the flags,
3694         * so there is a chance incompat flags are set on a rev 0 filesystem.
3695         */
3696        if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3697                goto failed_mount;
3698
3699        blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3700        if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3701            blocksize > EXT4_MAX_BLOCK_SIZE) {
3702                ext4_msg(sb, KERN_ERR,
3703                       "Unsupported filesystem blocksize %d", blocksize);
3704                goto failed_mount;
3705        }
3706
3707        if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3708                if (blocksize != PAGE_SIZE) {
3709                        ext4_msg(sb, KERN_ERR,
3710                                        "error: unsupported blocksize for dax");
3711                        goto failed_mount;
3712                }
3713                if (!sb->s_bdev->bd_disk->fops->direct_access) {
3714                        ext4_msg(sb, KERN_ERR,
3715                                        "error: device does not support dax");
3716                        goto failed_mount;
3717                }
3718        }
3719
3720        if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT) &&
3721            es->s_encryption_level) {
3722                ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3723                         es->s_encryption_level);
3724                goto failed_mount;
3725        }
3726
3727        if (sb->s_blocksize != blocksize) {
3728                /* Validate the filesystem blocksize */
3729                if (!sb_set_blocksize(sb, blocksize)) {
3730                        ext4_msg(sb, KERN_ERR, "bad block size %d",
3731                                        blocksize);
3732                        goto failed_mount;
3733                }
3734
3735                brelse(bh);
3736                logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3737                offset = do_div(logical_sb_block, blocksize);
3738                bh = sb_bread_unmovable(sb, logical_sb_block);
3739                if (!bh) {
3740                        ext4_msg(sb, KERN_ERR,
3741                               "Can't read superblock on 2nd try");
3742                        goto failed_mount;
3743                }
3744                es = (struct ext4_super_block *)(bh->b_data + offset);
3745                sbi->s_es = es;
3746                if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3747                        ext4_msg(sb, KERN_ERR,
3748                               "Magic mismatch, very weird!");
3749                        goto failed_mount;
3750                }
3751        }
3752
3753        has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3754                                EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3755        sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3756                                                      has_huge_files);
3757        sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3758
3759        if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3760                sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3761                sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3762        } else {
3763                sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3764                sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3765                if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3766                    (!is_power_of_2(sbi->s_inode_size)) ||
3767                    (sbi->s_inode_size > blocksize)) {
3768                        ext4_msg(sb, KERN_ERR,
3769                               "unsupported inode size: %d",
3770                               sbi->s_inode_size);
3771                        goto failed_mount;
3772                }
3773                if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3774                        sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3775        }
3776
3777        sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3778        if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3779                if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3780                    sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3781                    !is_power_of_2(sbi->s_desc_size)) {
3782                        ext4_msg(sb, KERN_ERR,
3783                               "unsupported descriptor size %lu",
3784                               sbi->s_desc_size);
3785                        goto failed_mount;
3786                }
3787        } else
3788                sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3789
3790        sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3791        sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3792        if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3793                goto cantfind_ext4;
3794
3795        sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3796        if (sbi->s_inodes_per_block == 0)
3797                goto cantfind_ext4;
3798        sbi->s_itb_per_group = sbi->s_inodes_per_group /
3799                                        sbi->s_inodes_per_block;
3800        sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3801        sbi->s_sbh = bh;
3802        sbi->s_mount_state = le16_to_cpu(es->s_state);
3803        sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3804        sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3805
3806        for (i = 0; i < 4; i++)
3807                sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3808        sbi->s_def_hash_version = es->s_def_hash_version;
3809        if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX)) {
3810                i = le32_to_cpu(es->s_flags);
3811                if (i & EXT2_FLAGS_UNSIGNED_HASH)
3812                        sbi->s_hash_unsigned = 3;
3813                else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3814#ifdef __CHAR_UNSIGNED__
3815                        if (!(sb->s_flags & MS_RDONLY))
3816                                es->s_flags |=
3817                                        cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3818                        sbi->s_hash_unsigned = 3;
3819#else
3820                        if (!(sb->s_flags & MS_RDONLY))
3821                                es->s_flags |=
3822                                        cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3823#endif
3824                }
3825        }
3826
3827        /* Handle clustersize */
3828        clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3829        has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3830                                EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3831        if (has_bigalloc) {
3832                if (clustersize < blocksize) {
3833                        ext4_msg(sb, KERN_ERR,
3834                                 "cluster size (%d) smaller than "
3835                                 "block size (%d)", clustersize, blocksize);
3836                        goto failed_mount;
3837                }
3838                sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3839                        le32_to_cpu(es->s_log_block_size);
3840                sbi->s_clusters_per_group =
3841                        le32_to_cpu(es->s_clusters_per_group);
3842                if (sbi->s_clusters_per_group > blocksize * 8) {
3843                        ext4_msg(sb, KERN_ERR,
3844                                 "#clusters per group too big: %lu",
3845                                 sbi->s_clusters_per_group);
3846                        goto failed_mount;
3847                }
3848                if (sbi->s_blocks_per_group !=
3849                    (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3850                        ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3851                                 "clusters per group (%lu) inconsistent",
3852                                 sbi->s_blocks_per_group,
3853                                 sbi->s_clusters_per_group);
3854                        goto failed_mount;
3855                }
3856        } else {
3857                if (clustersize != blocksize) {
3858                        ext4_warning(sb, "fragment/cluster size (%d) != "
3859                                     "block size (%d)", clustersize,
3860                                     blocksize);
3861                        clustersize = blocksize;
3862                }
3863                if (sbi->s_blocks_per_group > blocksize * 8) {
3864                        ext4_msg(sb, KERN_ERR,
3865                                 "#blocks per group too big: %lu",
3866                                 sbi->s_blocks_per_group);
3867                        goto failed_mount;
3868                }
3869                sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3870                sbi->s_cluster_bits = 0;
3871        }
3872        sbi->s_cluster_ratio = clustersize / blocksize;
3873
3874        if (sbi->s_inodes_per_group > blocksize * 8) {
3875                ext4_msg(sb, KERN_ERR,
3876                       "#inodes per group too big: %lu",
3877                       sbi->s_inodes_per_group);
3878                goto failed_mount;
3879        }
3880
3881        /* Do we have standard group size of clustersize * 8 blocks ? */
3882        if (sbi->s_blocks_per_group == clustersize << 3)
3883                set_opt2(sb, STD_GROUP_SIZE);
3884
3885        /*
3886         * Test whether we have more sectors than will fit in sector_t,
3887         * and whether the max offset is addressable by the page cache.
3888         */
3889        err = generic_check_addressable(sb->s_blocksize_bits,
3890                                        ext4_blocks_count(es));
3891        if (err) {
3892                ext4_msg(sb, KERN_ERR, "filesystem"
3893                         " too large to mount safely on this system");
3894                if (sizeof(sector_t) < 8)
3895                        ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3896                goto failed_mount;
3897        }
3898
3899        if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3900                goto cantfind_ext4;
3901
3902        /* check blocks count against device size */
3903        blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3904        if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3905                ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3906                       "exceeds size of device (%llu blocks)",
3907                       ext4_blocks_count(es), blocks_count);
3908                goto failed_mount;
3909        }
3910
3911        /*
3912         * It makes no sense for the first data block to be beyond the end
3913         * of the filesystem.
3914         */
3915        if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3916                ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3917                         "block %u is beyond end of filesystem (%llu)",
3918                         le32_to_cpu(es->s_first_data_block),
3919                         ext4_blocks_count(es));
3920                goto failed_mount;
3921        }
3922        blocks_count = (ext4_blocks_count(es) -
3923                        le32_to_cpu(es->s_first_data_block) +
3924                        EXT4_BLOCKS_PER_GROUP(sb) - 1);
3925        do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3926        if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3927                ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3928                       "(block count %llu, first data block %u, "
3929                       "blocks per group %lu)", sbi->s_groups_count,
3930                       ext4_blocks_count(es),
3931                       le32_to_cpu(es->s_first_data_block),
3932                       EXT4_BLOCKS_PER_GROUP(sb));
3933                goto failed_mount;
3934        }
3935        sbi->s_groups_count = blocks_count;
3936        sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3937                        (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3938        db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3939                   EXT4_DESC_PER_BLOCK(sb);
3940        sbi->s_group_desc = ext4_kvmalloc(db_count *
3941                                          sizeof(struct buffer_head *),
3942                                          GFP_KERNEL);
3943        if (sbi->s_group_desc == NULL) {
3944                ext4_msg(sb, KERN_ERR, "not enough memory");
3945                ret = -ENOMEM;
3946                goto failed_mount;
3947        }
3948
3949        if (ext4_proc_root)
3950                sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3951
3952        if (sbi->s_proc)
3953                proc_create_data("options", S_IRUGO, sbi->s_proc,
3954                                 &ext4_seq_options_fops, sb);
3955
3956        bgl_lock_init(sbi->s_blockgroup_lock);
3957
3958        for (i = 0; i < db_count; i++) {
3959                block = descriptor_loc(sb, logical_sb_block, i);
3960                sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
3961                if (!sbi->s_group_desc[i]) {
3962                        ext4_msg(sb, KERN_ERR,
3963                               "can't read group descriptor %d", i);
3964                        db_count = i;
3965                        goto failed_mount2;
3966                }
3967        }
3968        if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3969                ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3970                goto failed_mount2;
3971        }
3972
3973        sbi->s_gdb_count = db_count;
3974        get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3975        spin_lock_init(&sbi->s_next_gen_lock);
3976
3977        setup_timer(&sbi->s_err_report, print_daily_error_info,
3978                (unsigned long) sb);
3979
3980        /* Register extent status tree shrinker */
3981        if (ext4_es_register_shrinker(sbi))
3982                goto failed_mount3;
3983
3984        sbi->s_stripe = ext4_get_stripe_size(sbi);
3985        sbi->s_extent_max_zeroout_kb = 32;
3986
3987        /*
3988         * set up enough so that it can read an inode
3989         */
3990        sb->s_op = &ext4_sops;
3991        sb->s_export_op = &ext4_export_ops;
3992        sb->s_xattr = ext4_xattr_handlers;
3993#ifdef CONFIG_QUOTA
3994        sb->dq_op = &ext4_quota_operations;
3995        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA))
3996                sb->s_qcop = &dquot_quotactl_sysfile_ops;
3997        else
3998                sb->s_qcop = &ext4_qctl_operations;
3999        sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
4000#endif
4001        memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4002
4003        INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4004        mutex_init(&sbi->s_orphan_lock);
4005
4006        sb->s_root = NULL;
4007
4008        needs_recovery = (es->s_last_orphan != 0 ||
4009                          EXT4_HAS_INCOMPAT_FEATURE(sb,
4010                                    EXT4_FEATURE_INCOMPAT_RECOVER));
4011
4012        if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
4013            !(sb->s_flags & MS_RDONLY))
4014                if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4015                        goto failed_mount3a;
4016
4017        /*
4018         * The first inode we look at is the journal inode.  Don't try
4019         * root first: it may be modified in the journal!
4020         */
4021        if (!test_opt(sb, NOLOAD) &&
4022            EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4023                if (ext4_load_journal(sb, es, journal_devnum))
4024                        goto failed_mount3a;
4025        } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
4026              EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4027                ext4_msg(sb, KERN_ERR, "required journal recovery "
4028                       "suppressed and not mounted read-only");
4029                goto failed_mount_wq;
4030        } else {
4031                clear_opt(sb, DATA_FLAGS);
4032                sbi->s_journal = NULL;
4033                needs_recovery = 0;
4034                goto no_journal;
4035        }
4036
4037        if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) &&
4038            !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4039                                       JBD2_FEATURE_INCOMPAT_64BIT)) {
4040                ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4041                goto failed_mount_wq;
4042        }
4043
4044        if (!set_journal_csum_feature_set(sb)) {
4045                ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4046                         "feature set");
4047                goto failed_mount_wq;
4048        }
4049
4050        /* We have now updated the journal if required, so we can
4051         * validate the data journaling mode. */
4052        switch (test_opt(sb, DATA_FLAGS)) {
4053        case 0:
4054                /* No mode set, assume a default based on the journal
4055                 * capabilities: ORDERED_DATA if the journal can
4056                 * cope, else JOURNAL_DATA
4057                 */
4058                if (jbd2_journal_check_available_features
4059                    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
4060                        set_opt(sb, ORDERED_DATA);
4061                else
4062                        set_opt(sb, JOURNAL_DATA);
4063                break;
4064
4065        case EXT4_MOUNT_ORDERED_DATA:
4066        case EXT4_MOUNT_WRITEBACK_DATA:
4067                if (!jbd2_journal_check_available_features
4068                    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4069                        ext4_msg(sb, KERN_ERR, "Journal does not support "
4070                               "requested data journaling mode");
4071                        goto failed_mount_wq;
4072                }
4073        default:
4074                break;
4075        }
4076        set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4077
4078        sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4079
4080no_journal:
4081        if (ext4_mballoc_ready) {
4082                sbi->s_mb_cache = ext4_xattr_create_cache(sb->s_id);
4083                if (!sbi->s_mb_cache) {
4084                        ext4_msg(sb, KERN_ERR, "Failed to create an mb_cache");
4085                        goto failed_mount_wq;
4086                }
4087        }
4088
4089        if ((DUMMY_ENCRYPTION_ENABLED(sbi) ||
4090             EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT)) &&
4091            (blocksize != PAGE_CACHE_SIZE)) {
4092                ext4_msg(sb, KERN_ERR,
4093                         "Unsupported blocksize for fs encryption");
4094                goto failed_mount_wq;
4095        }
4096
4097        if (DUMMY_ENCRYPTION_ENABLED(sbi) &&
4098            !(sb->s_flags & MS_RDONLY) &&
4099            !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT)) {
4100                EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT);
4101                ext4_commit_super(sb, 1);
4102        }
4103
4104        /*
4105         * Get the # of file system overhead blocks from the
4106         * superblock if present.
4107         */
4108        if (es->s_overhead_clusters)
4109                sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4110        else {
4111                err = ext4_calculate_overhead(sb);
4112                if (err)
4113                        goto failed_mount_wq;
4114        }
4115
4116        /*
4117         * The maximum number of concurrent works can be high and
4118         * concurrency isn't really necessary.  Limit it to 1.
4119         */
4120        EXT4_SB(sb)->rsv_conversion_wq =
4121                alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4122        if (!EXT4_SB(sb)->rsv_conversion_wq) {
4123                printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4124                ret = -ENOMEM;
4125                goto failed_mount4;
4126        }
4127
4128        /*
4129         * The jbd2_journal_load will have done any necessary log recovery,
4130         * so we can safely mount the rest of the filesystem now.
4131         */
4132
4133        root = ext4_iget(sb, EXT4_ROOT_INO);
4134        if (IS_ERR(root)) {
4135                ext4_msg(sb, KERN_ERR, "get root inode failed");
4136                ret = PTR_ERR(root);
4137                root = NULL;
4138                goto failed_mount4;
4139        }
4140        if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4141                ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4142                iput(root);
4143                goto failed_mount4;
4144        }
4145        sb->s_root = d_make_root(root);
4146        if (!sb->s_root) {
4147                ext4_msg(sb, KERN_ERR, "get root dentry failed");
4148                ret = -ENOMEM;
4149                goto failed_mount4;
4150        }
4151
4152        if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
4153                sb->s_flags |= MS_RDONLY;
4154
4155        /* determine the minimum size of new large inodes, if present */
4156        if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4157                sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4158                                                     EXT4_GOOD_OLD_INODE_SIZE;
4159                if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
4160                                       EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
4161                        if (sbi->s_want_extra_isize <
4162                            le16_to_cpu(es->s_want_extra_isize))
4163                                sbi->s_want_extra_isize =
4164                                        le16_to_cpu(es->s_want_extra_isize);
4165                        if (sbi->s_want_extra_isize <
4166                            le16_to_cpu(es->s_min_extra_isize))
4167                                sbi->s_want_extra_isize =
4168                                        le16_to_cpu(es->s_min_extra_isize);
4169                }
4170        }
4171        /* Check if enough inode space is available */
4172        if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
4173                                                        sbi->s_inode_size) {
4174                sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4175                                                       EXT4_GOOD_OLD_INODE_SIZE;
4176                ext4_msg(sb, KERN_INFO, "required extra inode space not"
4177                         "available");
4178        }
4179
4180        err = ext4_reserve_clusters(sbi, ext4_calculate_resv_clusters(sb));
4181        if (err) {
4182                ext4_msg(sb, KERN_ERR, "failed to reserve %llu clusters for "
4183                         "reserved pool", ext4_calculate_resv_clusters(sb));
4184                goto failed_mount4a;
4185        }
4186
4187        err = ext4_setup_system_zone(sb);
4188        if (err) {
4189                ext4_msg(sb, KERN_ERR, "failed to initialize system "
4190                         "zone (%d)", err);
4191                goto failed_mount4a;
4192        }
4193
4194        ext4_ext_init(sb);
4195        err = ext4_mb_init(sb);
4196        if (err) {
4197                ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4198                         err);
4199                goto failed_mount5;
4200        }
4201
4202        block = ext4_count_free_clusters(sb);
4203        ext4_free_blocks_count_set(sbi->s_es, 
4204                                   EXT4_C2B(sbi, block));
4205        err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4206                                  GFP_KERNEL);
4207        if (!err) {
4208                unsigned long freei = ext4_count_free_inodes(sb);
4209                sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4210                err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4211                                          GFP_KERNEL);
4212        }
4213        if (!err)
4214                err = percpu_counter_init(&sbi->s_dirs_counter,
4215                                          ext4_count_dirs(sb), GFP_KERNEL);
4216        if (!err)
4217                err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4218                                          GFP_KERNEL);
4219        if (err) {
4220                ext4_msg(sb, KERN_ERR, "insufficient memory");
4221                goto failed_mount6;
4222        }
4223
4224        if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
4225                if (!ext4_fill_flex_info(sb)) {
4226                        ext4_msg(sb, KERN_ERR,
4227                               "unable to initialize "
4228                               "flex_bg meta info!");
4229                        goto failed_mount6;
4230                }
4231
4232        err = ext4_register_li_request(sb, first_not_zeroed);
4233        if (err)
4234                goto failed_mount6;
4235
4236        sbi->s_kobj.kset = ext4_kset;
4237        init_completion(&sbi->s_kobj_unregister);
4238        err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
4239                                   "%s", sb->s_id);
4240        if (err)
4241                goto failed_mount7;
4242
4243#ifdef CONFIG_QUOTA
4244        /* Enable quota usage during mount. */
4245        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
4246            !(sb->s_flags & MS_RDONLY)) {
4247                err = ext4_enable_quotas(sb);
4248                if (err)
4249                        goto failed_mount8;
4250        }
4251#endif  /* CONFIG_QUOTA */
4252
4253        EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4254        ext4_orphan_cleanup(sb, es);
4255        EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4256        if (needs_recovery) {
4257                ext4_msg(sb, KERN_INFO, "recovery complete");
4258                ext4_mark_recovery_complete(sb, es);
4259        }
4260        if (EXT4_SB(sb)->s_journal) {
4261                if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4262                        descr = " journalled data mode";
4263                else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4264                        descr = " ordered data mode";
4265                else
4266                        descr = " writeback data mode";
4267        } else
4268                descr = "out journal";
4269
4270        if (test_opt(sb, DISCARD)) {
4271                struct request_queue *q = bdev_get_queue(sb->s_bdev);
4272                if (!blk_queue_discard(q))
4273                        ext4_msg(sb, KERN_WARNING,
4274                                 "mounting with \"discard\" option, but "
4275                                 "the device does not support discard");
4276        }
4277
4278        ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4279                 "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
4280                 *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4281
4282        if (es->s_error_count)
4283                mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4284
4285        /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4286        ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4287        ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4288        ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4289
4290        kfree(orig_data);
4291        return 0;
4292
4293cantfind_ext4:
4294        if (!silent)
4295                ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4296        goto failed_mount;
4297
4298#ifdef CONFIG_QUOTA
4299failed_mount8:
4300        kobject_del(&sbi->s_kobj);
4301#endif
4302failed_mount7:
4303        ext4_unregister_li_request(sb);
4304failed_mount6:
4305        ext4_mb_release(sb);
4306        if (sbi->s_flex_groups)
4307                kvfree(sbi->s_flex_groups);
4308        percpu_counter_destroy(&sbi->s_freeclusters_counter);
4309        percpu_counter_destroy(&sbi->s_freeinodes_counter);
4310        percpu_counter_destroy(&sbi->s_dirs_counter);
4311        percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4312failed_mount5:
4313        ext4_ext_release(sb);
4314        ext4_release_system_zone(sb);
4315failed_mount4a:
4316        dput(sb->s_root);
4317        sb->s_root = NULL;
4318failed_mount4:
4319        ext4_msg(sb, KERN_ERR, "mount failed");
4320        if (EXT4_SB(sb)->rsv_conversion_wq)
4321                destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4322failed_mount_wq:
4323        if (sbi->s_journal) {
4324                jbd2_journal_destroy(sbi->s_journal);
4325                sbi->s_journal = NULL;
4326        }
4327failed_mount3a:
4328        ext4_es_unregister_shrinker(sbi);
4329failed_mount3:
4330        del_timer_sync(&sbi->s_err_report);
4331        if (sbi->s_mmp_tsk)
4332                kthread_stop(sbi->s_mmp_tsk);
4333failed_mount2:
4334        for (i = 0; i < db_count; i++)
4335                brelse(sbi->s_group_desc[i]);
4336        kvfree(sbi->s_group_desc);
4337failed_mount:
4338        if (sbi->s_chksum_driver)
4339                crypto_free_shash(sbi->s_chksum_driver);
4340        if (sbi->s_proc) {
4341                remove_proc_entry("options", sbi->s_proc);
4342                remove_proc_entry(sb->s_id, ext4_proc_root);
4343        }
4344#ifdef CONFIG_QUOTA
4345        for (i = 0; i < EXT4_MAXQUOTAS; i++)
4346                kfree(sbi->s_qf_names[i]);
4347#endif
4348        ext4_blkdev_remove(sbi);
4349        brelse(bh);
4350out_fail:
4351        sb->s_fs_info = NULL;
4352        kfree(sbi->s_blockgroup_lock);
4353        kfree(sbi);
4354out_free_orig:
4355        kfree(orig_data);
4356        return err ? err : ret;
4357}
4358
4359/*
4360 * Setup any per-fs journal parameters now.  We'll do this both on
4361 * initial mount, once the journal has been initialised but before we've
4362 * done any recovery; and again on any subsequent remount.
4363 */
4364static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4365{
4366        struct ext4_sb_info *sbi = EXT4_SB(sb);
4367
4368        journal->j_commit_interval = sbi->s_commit_interval;
4369        journal->j_min_batch_time = sbi->s_min_batch_time;
4370        journal->j_max_batch_time = sbi->s_max_batch_time;
4371
4372        write_lock(&journal->j_state_lock);
4373        if (test_opt(sb, BARRIER))
4374                journal->j_flags |= JBD2_BARRIER;
4375        else
4376                journal->j_flags &= ~JBD2_BARRIER;
4377        if (test_opt(sb, DATA_ERR_ABORT))
4378                journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4379        else
4380                journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4381        write_unlock(&journal->j_state_lock);
4382}
4383
4384static journal_t *ext4_get_journal(struct super_block *sb,
4385                                   unsigned int journal_inum)
4386{
4387        struct inode *journal_inode;
4388        journal_t *journal;
4389
4390        BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4391
4392        /* First, test for the existence of a valid inode on disk.  Bad
4393         * things happen if we iget() an unused inode, as the subsequent
4394         * iput() will try to delete it. */
4395
4396        journal_inode = ext4_iget(sb, journal_inum);
4397        if (IS_ERR(journal_inode)) {
4398                ext4_msg(sb, KERN_ERR, "no journal found");
4399                return NULL;
4400        }
4401        if (!journal_inode->i_nlink) {
4402                make_bad_inode(journal_inode);
4403                iput(journal_inode);
4404                ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4405                return NULL;
4406        }
4407
4408        jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4409                  journal_inode, journal_inode->i_size);
4410        if (!S_ISREG(journal_inode->i_mode)) {
4411                ext4_msg(sb, KERN_ERR, "invalid journal inode");
4412                iput(journal_inode);
4413                return NULL;
4414        }
4415
4416        journal = jbd2_journal_init_inode(journal_inode);
4417        if (!journal) {
4418                ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4419                iput(journal_inode);
4420                return NULL;
4421        }
4422        journal->j_private = sb;
4423        ext4_init_journal_params(sb, journal);
4424        return journal;
4425}
4426
4427static journal_t *ext4_get_dev_journal(struct super_block *sb,
4428                                       dev_t j_dev)
4429{
4430        struct buffer_head *bh;
4431        journal_t *journal;
4432        ext4_fsblk_t start;
4433        ext4_fsblk_t len;
4434        int hblock, blocksize;
4435        ext4_fsblk_t sb_block;
4436        unsigned long offset;
4437        struct ext4_super_block *es;
4438        struct block_device *bdev;
4439
4440        BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4441
4442        bdev = ext4_blkdev_get(j_dev, sb);
4443        if (bdev == NULL)
4444                return NULL;
4445
4446        blocksize = sb->s_blocksize;
4447        hblock = bdev_logical_block_size(bdev);
4448        if (blocksize < hblock) {
4449                ext4_msg(sb, KERN_ERR,
4450                        "blocksize too small for journal device");
4451                goto out_bdev;
4452        }
4453
4454        sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4455        offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4456        set_blocksize(bdev, blocksize);
4457        if (!(bh = __bread(bdev, sb_block, blocksize))) {
4458                ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4459                       "external journal");
4460                goto out_bdev;
4461        }
4462
4463        es = (struct ext4_super_block *) (bh->b_data + offset);
4464        if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4465            !(le32_to_cpu(es->s_feature_incompat) &
4466              EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4467                ext4_msg(sb, KERN_ERR, "external journal has "
4468                                        "bad superblock");
4469                brelse(bh);
4470                goto out_bdev;
4471        }
4472
4473        if ((le32_to_cpu(es->s_feature_ro_compat) &
4474             EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4475            es->s_checksum != ext4_superblock_csum(sb, es)) {
4476                ext4_msg(sb, KERN_ERR, "external journal has "
4477                                       "corrupt superblock");
4478                brelse(bh);
4479                goto out_bdev;
4480        }
4481
4482        if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4483                ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4484                brelse(bh);
4485                goto out_bdev;
4486        }
4487
4488        len = ext4_blocks_count(es);
4489        start = sb_block + 1;
4490        brelse(bh);     /* we're done with the superblock */
4491
4492        journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4493                                        start, len, blocksize);
4494        if (!journal) {
4495                ext4_msg(sb, KERN_ERR, "failed to create device journal");
4496                goto out_bdev;
4497        }
4498        journal->j_private = sb;
4499        ll_rw_block(READ | REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4500        wait_on_buffer(journal->j_sb_buffer);
4501        if (!buffer_uptodate(journal->j_sb_buffer)) {
4502                ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4503                goto out_journal;
4504        }
4505        if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4506                ext4_msg(sb, KERN_ERR, "External journal has more than one "
4507                                        "user (unsupported) - %d",
4508                        be32_to_cpu(journal->j_superblock->s_nr_users));
4509                goto out_journal;
4510        }
4511        EXT4_SB(sb)->journal_bdev = bdev;
4512        ext4_init_journal_params(sb, journal);
4513        return journal;
4514
4515out_journal:
4516        jbd2_journal_destroy(journal);
4517out_bdev:
4518        ext4_blkdev_put(bdev);
4519        return NULL;
4520}
4521
4522static int ext4_load_journal(struct super_block *sb,
4523                             struct ext4_super_block *es,
4524                             unsigned long journal_devnum)
4525{
4526        journal_t *journal;
4527        unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4528        dev_t journal_dev;
4529        int err = 0;
4530        int really_read_only;
4531
4532        BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4533
4534        if (journal_devnum &&
4535            journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4536                ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4537                        "numbers have changed");
4538                journal_dev = new_decode_dev(journal_devnum);
4539        } else
4540                journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4541
4542        really_read_only = bdev_read_only(sb->s_bdev);
4543
4544        /*
4545         * Are we loading a blank journal or performing recovery after a
4546         * crash?  For recovery, we need to check in advance whether we
4547         * can get read-write access to the device.
4548         */
4549        if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
4550                if (sb->s_flags & MS_RDONLY) {
4551                        ext4_msg(sb, KERN_INFO, "INFO: recovery "
4552                                        "required on readonly filesystem");
4553                        if (really_read_only) {
4554                                ext4_msg(sb, KERN_ERR, "write access "
4555                                        "unavailable, cannot proceed");
4556                                return -EROFS;
4557                        }
4558                        ext4_msg(sb, KERN_INFO, "write access will "
4559                               "be enabled during recovery");
4560                }
4561        }
4562
4563        if (journal_inum && journal_dev) {
4564                ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4565                       "and inode journals!");
4566                return -EINVAL;
4567        }
4568
4569        if (journal_inum) {
4570                if (!(journal = ext4_get_journal(sb, journal_inum)))
4571                        return -EINVAL;
4572        } else {
4573                if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4574                        return -EINVAL;
4575        }
4576
4577        if (!(journal->j_flags & JBD2_BARRIER))
4578                ext4_msg(sb, KERN_INFO, "barriers disabled");
4579
4580        if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
4581                err = jbd2_journal_wipe(journal, !really_read_only);
4582        if (!err) {
4583                char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4584                if (save)
4585                        memcpy(save, ((char *) es) +
4586                               EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4587                err = jbd2_journal_load(journal);
4588                if (save)
4589                        memcpy(((char *) es) + EXT4_S_ERR_START,
4590                               save, EXT4_S_ERR_LEN);
4591                kfree(save);
4592        }
4593
4594        if (err) {
4595                ext4_msg(sb, KERN_ERR, "error loading journal");
4596                jbd2_journal_destroy(journal);
4597                return err;
4598        }
4599
4600        EXT4_SB(sb)->s_journal = journal;
4601        ext4_clear_journal_err(sb, es);
4602
4603        if (!really_read_only && journal_devnum &&
4604            journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4605                es->s_journal_dev = cpu_to_le32(journal_devnum);
4606
4607                /* Make sure we flush the recovery flag to disk. */
4608                ext4_commit_super(sb, 1);
4609        }
4610
4611        return 0;
4612}
4613
4614static int ext4_commit_super(struct super_block *sb, int sync)
4615{
4616        struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4617        struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4618        int error = 0;
4619
4620        if (!sbh)
4621                return error;
4622        if (buffer_write_io_error(sbh)) {
4623                /*
4624                 * Oh, dear.  A previous attempt to write the
4625                 * superblock failed.  This could happen because the
4626                 * USB device was yanked out.  Or it could happen to
4627                 * be a transient write error and maybe the block will
4628                 * be remapped.  Nothing we can do but to retry the
4629                 * write and hope for the best.
4630                 */
4631                ext4_msg(sb, KERN_ERR, "previous I/O error to "
4632                       "superblock detected");
4633                clear_buffer_write_io_error(sbh);
4634                set_buffer_uptodate(sbh);
4635        }
4636        /*
4637         * If the file system is mounted read-only, don't update the
4638         * superblock write time.  This avoids updating the superblock
4639         * write time when we are mounting the root file system
4640         * read/only but we need to replay the journal; at that point,
4641         * for people who are east of GMT and who make their clock
4642         * tick in localtime for Windows bug-for-bug compatibility,
4643         * the clock is set in the future, and this will cause e2fsck
4644         * to complain and force a full file system check.
4645         */
4646        if (!(sb->s_flags & MS_RDONLY))
4647                es->s_wtime = cpu_to_le32(get_seconds());
4648        if (sb->s_bdev->bd_part)
4649                es->s_kbytes_written =
4650                        cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4651                            ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4652                              EXT4_SB(sb)->s_sectors_written_start) >> 1));
4653        else
4654                es->s_kbytes_written =
4655                        cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4656        if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4657                ext4_free_blocks_count_set(es,
4658                        EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4659                                &EXT4_SB(sb)->s_freeclusters_counter)));
4660        if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4661                es->s_free_inodes_count =
4662                        cpu_to_le32(percpu_counter_sum_positive(
4663                                &EXT4_SB(sb)->s_freeinodes_counter));
4664        BUFFER_TRACE(sbh, "marking dirty");
4665        ext4_superblock_csum_set(sb);
4666        mark_buffer_dirty(sbh);
4667        if (sync) {
4668                error = sync_dirty_buffer(sbh);
4669                if (error)
4670                        return error;
4671
4672                error = buffer_write_io_error(sbh);
4673                if (error) {
4674                        ext4_msg(sb, KERN_ERR, "I/O error while writing "
4675                               "superblock");
4676                        clear_buffer_write_io_error(sbh);
4677                        set_buffer_uptodate(sbh);
4678                }
4679        }
4680        return error;
4681}
4682
4683/*
4684 * Have we just finished recovery?  If so, and if we are mounting (or
4685 * remounting) the filesystem readonly, then we will end up with a
4686 * consistent fs on disk.  Record that fact.
4687 */
4688static void ext4_mark_recovery_complete(struct super_block *sb,
4689                                        struct ext4_super_block *es)
4690{
4691        journal_t *journal = EXT4_SB(sb)->s_journal;
4692
4693        if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
4694                BUG_ON(journal != NULL);
4695                return;
4696        }
4697        jbd2_journal_lock_updates(journal);
4698        if (jbd2_journal_flush(journal) < 0)
4699                goto out;
4700
4701        if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
4702            sb->s_flags & MS_RDONLY) {
4703                EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4704                ext4_commit_super(sb, 1);
4705        }
4706
4707out:
4708        jbd2_journal_unlock_updates(journal);
4709}
4710
4711/*
4712 * If we are mounting (or read-write remounting) a filesystem whose journal
4713 * has recorded an error from a previous lifetime, move that error to the
4714 * main filesystem now.
4715 */
4716static void ext4_clear_journal_err(struct super_block *sb,
4717                                   struct ext4_super_block *es)
4718{
4719        journal_t *journal;
4720        int j_errno;
4721        const char *errstr;
4722
4723        BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
4724
4725        journal = EXT4_SB(sb)->s_journal;
4726
4727        /*
4728         * Now check for any error status which may have been recorded in the
4729         * journal by a prior ext4_error() or ext4_abort()
4730         */
4731
4732        j_errno = jbd2_journal_errno(journal);
4733        if (j_errno) {
4734                char nbuf[16];
4735
4736                errstr = ext4_decode_error(sb, j_errno, nbuf);
4737                ext4_warning(sb, "Filesystem error recorded "
4738                             "from previous mount: %s", errstr);
4739                ext4_warning(sb, "Marking fs in need of filesystem check.");
4740
4741                EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4742                es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4743                ext4_commit_super(sb, 1);
4744
4745                jbd2_journal_clear_err(journal);
4746                jbd2_journal_update_sb_errno(journal);
4747        }
4748}
4749
4750/*
4751 * Force the running and committing transactions to commit,
4752 * and wait on the commit.
4753 */
4754int ext4_force_commit(struct super_block *sb)
4755{
4756        journal_t *journal;
4757
4758        if (sb->s_flags & MS_RDONLY)
4759                return 0;
4760
4761        journal = EXT4_SB(sb)->s_journal;
4762        return ext4_journal_force_commit(journal);
4763}
4764
4765static int ext4_sync_fs(struct super_block *sb, int wait)
4766{
4767        int ret = 0;
4768        tid_t target;
4769        bool needs_barrier = false;
4770        struct ext4_sb_info *sbi = EXT4_SB(sb);
4771
4772        trace_ext4_sync_fs(sb, wait);
4773        flush_workqueue(sbi->rsv_conversion_wq);
4774        /*
4775         * Writeback quota in non-journalled quota case - journalled quota has
4776         * no dirty dquots
4777         */
4778        dquot_writeback_dquots(sb, -1);
4779        /*
4780         * Data writeback is possible w/o journal transaction, so barrier must
4781         * being sent at the end of the function. But we can skip it if
4782         * transaction_commit will do it for us.
4783         */
4784        if (sbi->s_journal) {
4785                target = jbd2_get_latest_transaction(sbi->s_journal);
4786                if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
4787                    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
4788                        needs_barrier = true;
4789
4790                if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4791                        if (wait)
4792                                ret = jbd2_log_wait_commit(sbi->s_journal,
4793                                                           target);
4794                }
4795        } else if (wait && test_opt(sb, BARRIER))
4796                needs_barrier = true;
4797        if (needs_barrier) {
4798                int err;
4799                err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4800                if (!ret)
4801                        ret = err;
4802        }
4803
4804        return ret;
4805}
4806
4807/*
4808 * LVM calls this function before a (read-only) snapshot is created.  This
4809 * gives us a chance to flush the journal completely and mark the fs clean.
4810 *
4811 * Note that only this function cannot bring a filesystem to be in a clean
4812 * state independently. It relies on upper layer to stop all data & metadata
4813 * modifications.
4814 */
4815static int ext4_freeze(struct super_block *sb)
4816{
4817        int error = 0;
4818        journal_t *journal;
4819
4820        if (sb->s_flags & MS_RDONLY)
4821                return 0;
4822
4823        journal = EXT4_SB(sb)->s_journal;
4824
4825        if (journal) {
4826                /* Now we set up the journal barrier. */
4827                jbd2_journal_lock_updates(journal);
4828
4829                /*
4830                 * Don't clear the needs_recovery flag if we failed to
4831                 * flush the journal.
4832                 */
4833                error = jbd2_journal_flush(journal);
4834                if (error < 0)
4835                        goto out;
4836        }
4837
4838        /* Journal blocked and flushed, clear needs_recovery flag. */
4839        EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4840        error = ext4_commit_super(sb, 1);
4841out:
4842        if (journal)
4843                /* we rely on upper layer to stop further updates */
4844                jbd2_journal_unlock_updates(journal);
4845        return error;
4846}
4847
4848/*
4849 * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4850 * flag here, even though the filesystem is not technically dirty yet.
4851 */
4852static int ext4_unfreeze(struct super_block *sb)
4853{
4854        if (sb->s_flags & MS_RDONLY)
4855                return 0;
4856
4857        /* Reset the needs_recovery flag before the fs is unlocked. */
4858        EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
4859        ext4_commit_super(sb, 1);
4860        return 0;
4861}
4862
4863/*
4864 * Structure to save mount options for ext4_remount's benefit
4865 */
4866struct ext4_mount_options {
4867        unsigned long s_mount_opt;
4868        unsigned long s_mount_opt2;
4869        kuid_t s_resuid;
4870        kgid_t s_resgid;
4871        unsigned long s_commit_interval;
4872        u32 s_min_batch_time, s_max_batch_time;
4873#ifdef CONFIG_QUOTA
4874        int s_jquota_fmt;
4875        char *s_qf_names[EXT4_MAXQUOTAS];
4876#endif
4877};
4878
4879static int ext4_remount(struct super_block *sb, int *flags, char *data)
4880{
4881        struct ext4_super_block *es;
4882        struct ext4_sb_info *sbi = EXT4_SB(sb);
4883        unsigned long old_sb_flags;
4884        struct ext4_mount_options old_opts;
4885        int enable_quota = 0;
4886        ext4_group_t g;
4887        unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4888        int err = 0;
4889#ifdef CONFIG_QUOTA
4890        int i, j;
4891#endif
4892        char *orig_data = kstrdup(data, GFP_KERNEL);
4893
4894        /* Store the original options */
4895        old_sb_flags = sb->s_flags;
4896        old_opts.s_mount_opt = sbi->s_mount_opt;
4897        old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4898        old_opts.s_resuid = sbi->s_resuid;
4899        old_opts.s_resgid = sbi->s_resgid;
4900        old_opts.s_commit_interval = sbi->s_commit_interval;
4901        old_opts.s_min_batch_time = sbi->s_min_batch_time;
4902        old_opts.s_max_batch_time = sbi->s_max_batch_time;
4903#ifdef CONFIG_QUOTA
4904        old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4905        for (i = 0; i < EXT4_MAXQUOTAS; i++)
4906                if (sbi->s_qf_names[i]) {
4907                        old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
4908                                                         GFP_KERNEL);
4909                        if (!old_opts.s_qf_names[i]) {
4910                                for (j = 0; j < i; j++)
4911                                        kfree(old_opts.s_qf_names[j]);
4912                                kfree(orig_data);
4913                                return -ENOMEM;
4914                        }
4915                } else
4916                        old_opts.s_qf_names[i] = NULL;
4917#endif
4918        if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4919                journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4920
4921        if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4922                err = -EINVAL;
4923                goto restore_opts;
4924        }
4925
4926        if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
4927            test_opt(sb, JOURNAL_CHECKSUM)) {
4928                ext4_msg(sb, KERN_ERR, "changing journal_checksum "
4929                         "during remount not supported; ignoring");
4930                sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
4931        }
4932
4933        if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4934                if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4935                        ext4_msg(sb, KERN_ERR, "can't mount with "
4936                                 "both data=journal and delalloc");
4937                        err = -EINVAL;
4938                        goto restore_opts;
4939                }
4940                if (test_opt(sb, DIOREAD_NOLOCK)) {
4941                        ext4_msg(sb, KERN_ERR, "can't mount with "
4942                                 "both data=journal and dioread_nolock");
4943                        err = -EINVAL;
4944                        goto restore_opts;
4945                }
4946                if (test_opt(sb, DAX)) {
4947                        ext4_msg(sb, KERN_ERR, "can't mount with "
4948                                 "both data=journal and dax");
4949                        err = -EINVAL;
4950                        goto restore_opts;
4951                }
4952        }
4953
4954        if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
4955                ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
4956                        "dax flag with busy inodes while remounting");
4957                sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
4958        }
4959
4960        if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
4961                ext4_abort(sb, "Abort forced by user");
4962
4963        sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
4964                (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
4965
4966        es = sbi->s_es;
4967
4968        if (sbi->s_journal) {
4969                ext4_init_journal_params(sb, sbi->s_journal);
4970                set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4971        }
4972
4973        if (*flags & MS_LAZYTIME)
4974                sb->s_flags |= MS_LAZYTIME;
4975
4976        if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
4977                if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
4978                        err = -EROFS;
4979                        goto restore_opts;
4980                }
4981
4982                if (*flags & MS_RDONLY) {
4983                        err = sync_filesystem(sb);
4984                        if (err < 0)
4985                                goto restore_opts;
4986                        err = dquot_suspend(sb, -1);
4987                        if (err < 0)
4988                                goto restore_opts;
4989
4990                        /*
4991                         * First of all, the unconditional stuff we have to do
4992                         * to disable replay of the journal when we next remount
4993                         */
4994                        sb->s_flags |= MS_RDONLY;
4995
4996                        /*
4997                         * OK, test if we are remounting a valid rw partition
4998                         * readonly, and if so set the rdonly flag and then
4999                         * mark the partition as valid again.
5000                         */
5001                        if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5002                            (sbi->s_mount_state & EXT4_VALID_FS))
5003                                es->s_state = cpu_to_le16(sbi->s_mount_state);
5004
5005                        if (sbi->s_journal)
5006                                ext4_mark_recovery_complete(sb, es);
5007                } else {
5008                        /* Make sure we can mount this feature set readwrite */
5009                        if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
5010                                        EXT4_FEATURE_RO_COMPAT_READONLY) ||
5011                            !ext4_feature_set_ok(sb, 0)) {
5012                                err = -EROFS;
5013                                goto restore_opts;
5014                        }
5015                        /*
5016                         * Make sure the group descriptor checksums
5017                         * are sane.  If they aren't, refuse to remount r/w.
5018                         */
5019                        for (g = 0; g < sbi->s_groups_count; g++) {
5020                                struct ext4_group_desc *gdp =
5021                                        ext4_get_group_desc(sb, g, NULL);
5022
5023                                if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5024                                        ext4_msg(sb, KERN_ERR,
5025               "ext4_remount: Checksum for group %u failed (%u!=%u)",
5026                g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
5027                                               le16_to_cpu(gdp->bg_checksum));
5028                                        err = -EINVAL;
5029                                        goto restore_opts;
5030                                }
5031                        }
5032
5033                        /*
5034                         * If we have an unprocessed orphan list hanging
5035                         * around from a previously readonly bdev mount,
5036                         * require a full umount/remount for now.
5037                         */
5038                        if (es->s_last_orphan) {
5039                                ext4_msg(sb, KERN_WARNING, "Couldn't "
5040                                       "remount RDWR because of unprocessed "
5041                                       "orphan inode list.  Please "
5042                                       "umount/remount instead");
5043                                err = -EINVAL;
5044                                goto restore_opts;
5045                        }
5046
5047                        /*
5048                         * Mounting a RDONLY partition read-write, so reread
5049                         * and store the current valid flag.  (It may have
5050                         * been changed by e2fsck since we originally mounted
5051                         * the partition.)
5052                         */
5053                        if (sbi->s_journal)
5054                                ext4_clear_journal_err(sb, es);
5055                        sbi->s_mount_state = le16_to_cpu(es->s_state);
5056                        if (!ext4_setup_super(sb, es, 0))
5057                                sb->s_flags &= ~MS_RDONLY;
5058                        if (EXT4_HAS_INCOMPAT_FEATURE(sb,
5059                                                     EXT4_FEATURE_INCOMPAT_MMP))
5060                                if (ext4_multi_mount_protect(sb,
5061                                                le64_to_cpu(es->s_mmp_block))) {
5062                                        err = -EROFS;
5063                                        goto restore_opts;
5064                                }
5065                        enable_quota = 1;
5066                }
5067        }
5068
5069        /*
5070         * Reinitialize lazy itable initialization thread based on
5071         * current settings
5072         */
5073        if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
5074                ext4_unregister_li_request(sb);
5075        else {
5076                ext4_group_t first_not_zeroed;
5077                first_not_zeroed = ext4_has_uninit_itable(sb);
5078                ext4_register_li_request(sb, first_not_zeroed);
5079        }
5080
5081        ext4_setup_system_zone(sb);
5082        if (sbi->s_journal == NULL && !(old_sb_flags & MS_RDONLY))
5083                ext4_commit_super(sb, 1);
5084
5085#ifdef CONFIG_QUOTA
5086        /* Release old quota file names */
5087        for (i = 0; i < EXT4_MAXQUOTAS; i++)
5088                kfree(old_opts.s_qf_names[i]);
5089        if (enable_quota) {
5090                if (sb_any_quota_suspended(sb))
5091                        dquot_resume(sb, -1);
5092                else if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
5093                                        EXT4_FEATURE_RO_COMPAT_QUOTA)) {
5094                        err = ext4_enable_quotas(sb);
5095                        if (err)
5096                                goto restore_opts;
5097                }
5098        }
5099#endif
5100
5101        *flags = (*flags & ~MS_LAZYTIME) | (sb->s_flags & MS_LAZYTIME);
5102        ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5103        kfree(orig_data);
5104        return 0;
5105
5106restore_opts:
5107        sb->s_flags = old_sb_flags;
5108        sbi->s_mount_opt = old_opts.s_mount_opt;
5109        sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5110        sbi->s_resuid = old_opts.s_resuid;
5111        sbi->s_resgid = old_opts.s_resgid;
5112        sbi->s_commit_interval = old_opts.s_commit_interval;
5113        sbi->s_min_batch_time = old_opts.s_min_batch_time;
5114        sbi->s_max_batch_time = old_opts.s_max_batch_time;
5115#ifdef CONFIG_QUOTA
5116        sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5117        for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5118                kfree(sbi->s_qf_names[i]);
5119                sbi->s_qf_names[i] = old_opts.s_qf_names[i];
5120        }
5121#endif
5122        kfree(orig_data);
5123        return err;
5124}
5125
5126static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5127{
5128        struct super_block *sb = dentry->d_sb;
5129        struct ext4_sb_info *sbi = EXT4_SB(sb);
5130        struct ext4_super_block *es = sbi->s_es;
5131        ext4_fsblk_t overhead = 0, resv_blocks;
5132        u64 fsid;
5133        s64 bfree;
5134        resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5135
5136        if (!test_opt(sb, MINIX_DF))
5137                overhead = sbi->s_overhead;
5138
5139        buf->f_type = EXT4_SUPER_MAGIC;
5140        buf->f_bsize = sb->s_blocksize;
5141        buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5142        bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5143                percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5144        /* prevent underflow in case that few free space is available */
5145        buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5146        buf->f_bavail = buf->f_bfree -
5147                        (ext4_r_blocks_count(es) + resv_blocks);
5148        if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5149                buf->f_bavail = 0;
5150        buf->f_files = le32_to_cpu(es->s_inodes_count);
5151        buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5152        buf->f_namelen = EXT4_NAME_LEN;
5153        fsid = le64_to_cpup((void *)es->s_uuid) ^
5154               le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5155        buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5156        buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5157
5158        return 0;
5159}
5160
5161/* Helper function for writing quotas on sync - we need to start transaction
5162 * before quota file is locked for write. Otherwise the are possible deadlocks:
5163 * Process 1                         Process 2
5164 * ext4_create()                     quota_sync()
5165 *   jbd2_journal_start()                  write_dquot()
5166 *   dquot_initialize()                         down(dqio_mutex)
5167 *     down(dqio_mutex)                    jbd2_journal_start()
5168 *
5169 */
5170
5171#ifdef CONFIG_QUOTA
5172
5173static inline struct inode *dquot_to_inode(struct dquot *dquot)
5174{
5175        return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5176}
5177
5178static int ext4_write_dquot(struct dquot *dquot)
5179{
5180        int ret, err;
5181        handle_t *handle;
5182        struct inode *inode;
5183
5184        inode = dquot_to_inode(dquot);
5185        handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5186                                    EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5187        if (IS_ERR(handle))
5188                return PTR_ERR(handle);
5189        ret = dquot_commit(dquot);
5190        err = ext4_journal_stop(handle);
5191        if (!ret)
5192                ret = err;
5193        return ret;
5194}
5195
5196static int ext4_acquire_dquot(struct dquot *dquot)
5197{
5198        int ret, err;
5199        handle_t *handle;
5200
5201        handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5202                                    EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5203        if (IS_ERR(handle))
5204                return PTR_ERR(handle);
5205        ret = dquot_acquire(dquot);
5206        err = ext4_journal_stop(handle);
5207        if (!ret)
5208                ret = err;
5209        return ret;
5210}
5211
5212static int ext4_release_dquot(struct dquot *dquot)
5213{
5214        int ret, err;
5215        handle_t *handle;
5216
5217        handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5218                                    EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5219        if (IS_ERR(handle)) {
5220                /* Release dquot anyway to avoid endless cycle in dqput() */
5221                dquot_release(dquot);
5222                return PTR_ERR(handle);
5223        }
5224        ret = dquot_release(dquot);
5225        err = ext4_journal_stop(handle);
5226        if (!ret)
5227                ret = err;
5228        return ret;
5229}
5230
5231static int ext4_mark_dquot_dirty(struct dquot *dquot)
5232{
5233        struct super_block *sb = dquot->dq_sb;
5234        struct ext4_sb_info *sbi = EXT4_SB(sb);
5235
5236        /* Are we journaling quotas? */
5237        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) ||
5238            sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5239                dquot_mark_dquot_dirty(dquot);
5240                return ext4_write_dquot(dquot);
5241        } else {
5242                return dquot_mark_dquot_dirty(dquot);
5243        }
5244}
5245
5246static int ext4_write_info(struct super_block *sb, int type)
5247{
5248        int ret, err;
5249        handle_t *handle;
5250
5251        /* Data block + inode block */
5252        handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5253        if (IS_ERR(handle))
5254                return PTR_ERR(handle);
5255        ret = dquot_commit_info(sb, type);
5256        err = ext4_journal_stop(handle);
5257        if (!ret)
5258                ret = err;
5259        return ret;
5260}
5261
5262/*
5263 * Turn on quotas during mount time - we need to find
5264 * the quota file and such...
5265 */
5266static int ext4_quota_on_mount(struct super_block *sb, int type)
5267{
5268        return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
5269                                        EXT4_SB(sb)->s_jquota_fmt, type);
5270}
5271
5272/*
5273 * Standard function to be called on quota_on
5274 */
5275static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5276                         struct path *path)
5277{
5278        int err;
5279
5280        if (!test_opt(sb, QUOTA))
5281                return -EINVAL;
5282
5283        /* Quotafile not on the same filesystem? */
5284        if (path->dentry->d_sb != sb)
5285                return -EXDEV;
5286        /* Journaling quota? */
5287        if (EXT4_SB(sb)->s_qf_names[type]) {
5288                /* Quotafile not in fs root? */
5289                if (path->dentry->d_parent != sb->s_root)
5290                        ext4_msg(sb, KERN_WARNING,
5291                                "Quota file not on filesystem root. "
5292                                "Journaled quota will not work");
5293        }
5294
5295        /*
5296         * When we journal data on quota file, we have to flush journal to see
5297         * all updates to the file when we bypass pagecache...
5298         */
5299        if (EXT4_SB(sb)->s_journal &&
5300            ext4_should_journal_data(d_inode(path->dentry))) {
5301                /*
5302                 * We don't need to lock updates but journal_flush() could
5303                 * otherwise be livelocked...
5304                 */
5305                jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5306                err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5307                jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5308                if (err)
5309                        return err;
5310        }
5311
5312        return dquot_quota_on(sb, type, format_id, path);
5313}
5314
5315static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5316                             unsigned int flags)
5317{
5318        int err;
5319        struct inode *qf_inode;
5320        unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5321                le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5322                le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
5323        };
5324
5325        BUG_ON(!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA));
5326
5327        if (!qf_inums[type])
5328                return -EPERM;
5329
5330        qf_inode = ext4_iget(sb, qf_inums[type]);
5331        if (IS_ERR(qf_inode)) {
5332                ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5333                return PTR_ERR(qf_inode);
5334        }
5335
5336        /* Don't account quota for quota files to avoid recursion */
5337        qf_inode->i_flags |= S_NOQUOTA;
5338        err = dquot_enable(qf_inode, type, format_id, flags);
5339        iput(qf_inode);
5340
5341        return err;
5342}
5343
5344/* Enable usage tracking for all quota types. */
5345static int ext4_enable_quotas(struct super_block *sb)
5346{
5347        int type, err = 0;
5348        unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5349                le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5350                le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum)
5351        };
5352
5353        sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
5354        for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5355                if (qf_inums[type]) {
5356                        err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5357                                                DQUOT_USAGE_ENABLED);
5358                        if (err) {
5359                                ext4_warning(sb,
5360                                        "Failed to enable quota tracking "
5361                                        "(type=%d, err=%d). Please run "
5362                                        "e2fsck to fix.", type, err);
5363                                return err;
5364                        }
5365                }
5366        }
5367        return 0;
5368}
5369
5370static int ext4_quota_off(struct super_block *sb, int type)
5371{
5372        struct inode *inode = sb_dqopt(sb)->files[type];
5373        handle_t *handle;
5374
5375        /* Force all delayed allocation blocks to be allocated.
5376         * Caller already holds s_umount sem */
5377        if (test_opt(sb, DELALLOC))
5378                sync_filesystem(sb);
5379
5380        if (!inode)
5381                goto out;
5382
5383        /* Update modification times of quota files when userspace can
5384         * start looking at them */
5385        handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5386        if (IS_ERR(handle))
5387                goto out;
5388        inode->i_mtime = inode->i_ctime = CURRENT_TIME;
5389        ext4_mark_inode_dirty(handle, inode);
5390        ext4_journal_stop(handle);
5391
5392out:
5393        return dquot_quota_off(sb, type);
5394}
5395
5396/* Read data from quotafile - avoid pagecache and such because we cannot afford
5397 * acquiring the locks... As quota files are never truncated and quota code
5398 * itself serializes the operations (and no one else should touch the files)
5399 * we don't have to be afraid of races */
5400static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5401                               size_t len, loff_t off)
5402{
5403        struct inode *inode = sb_dqopt(sb)->files[type];
5404        ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5405        int offset = off & (sb->s_blocksize - 1);
5406        int tocopy;
5407        size_t toread;
5408        struct buffer_head *bh;
5409        loff_t i_size = i_size_read(inode);
5410
5411        if (off > i_size)
5412                return 0;
5413        if (off+len > i_size)
5414                len = i_size-off;
5415        toread = len;
5416        while (toread > 0) {
5417                tocopy = sb->s_blocksize - offset < toread ?
5418                                sb->s_blocksize - offset : toread;
5419                bh = ext4_bread(NULL, inode, blk, 0);
5420                if (IS_ERR(bh))
5421                        return PTR_ERR(bh);
5422                if (!bh)        /* A hole? */
5423                        memset(data, 0, tocopy);
5424                else
5425                        memcpy(data, bh->b_data+offset, tocopy);
5426                brelse(bh);
5427                offset = 0;
5428                toread -= tocopy;
5429                data += tocopy;
5430                blk++;
5431        }
5432        return len;
5433}
5434
5435/* Write to quotafile (we know the transaction is already started and has
5436 * enough credits) */
5437static ssize_t ext4_quota_write(struct super_block *sb, int type,
5438                                const char *data, size_t len, loff_t off)
5439{
5440        struct inode *inode = sb_dqopt(sb)->files[type];
5441        ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5442        int err, offset = off & (sb->s_blocksize - 1);
5443        int retries = 0;
5444        struct buffer_head *bh;
5445        handle_t *handle = journal_current_handle();
5446
5447        if (EXT4_SB(sb)->s_journal && !handle) {
5448                ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5449                        " cancelled because transaction is not started",
5450                        (unsigned long long)off, (unsigned long long)len);
5451                return -EIO;
5452        }
5453        /*
5454         * Since we account only one data block in transaction credits,
5455         * then it is impossible to cross a block boundary.
5456         */
5457        if (sb->s_blocksize - offset < len) {
5458                ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5459                        " cancelled because not block aligned",
5460                        (unsigned long long)off, (unsigned long long)len);
5461                return -EIO;
5462        }
5463
5464        do {
5465                bh = ext4_bread(handle, inode, blk,
5466                                EXT4_GET_BLOCKS_CREATE |
5467                                EXT4_GET_BLOCKS_METADATA_NOFAIL);
5468        } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5469                 ext4_should_retry_alloc(inode->i_sb, &retries));
5470        if (IS_ERR(bh))
5471                return PTR_ERR(bh);
5472        if (!bh)
5473                goto out;
5474        BUFFER_TRACE(bh, "get write access");
5475        err = ext4_journal_get_write_access(handle, bh);
5476        if (err) {
5477                brelse(bh);
5478                return err;
5479        }
5480        lock_buffer(bh);
5481        memcpy(bh->b_data+offset, data, len);
5482        flush_dcache_page(bh->b_page);
5483        unlock_buffer(bh);
5484        err = ext4_handle_dirty_metadata(handle, NULL, bh);
5485        brelse(bh);
5486out:
5487        if (inode->i_size < off + len) {
5488                i_size_write(inode, off + len);
5489                EXT4_I(inode)->i_disksize = inode->i_size;
5490                ext4_mark_inode_dirty(handle, inode);
5491        }
5492        return len;
5493}
5494
5495#endif
5496
5497static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5498                       const char *dev_name, void *data)
5499{
5500        return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5501}
5502
5503#if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5504static inline void register_as_ext2(void)
5505{
5506        int err = register_filesystem(&ext2_fs_type);
5507        if (err)
5508                printk(KERN_WARNING
5509                       "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5510}
5511
5512static inline void unregister_as_ext2(void)
5513{
5514        unregister_filesystem(&ext2_fs_type);
5515}
5516
5517static inline int ext2_feature_set_ok(struct super_block *sb)
5518{
5519        if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))
5520                return 0;
5521        if (sb->s_flags & MS_RDONLY)
5522                return 1;
5523        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))
5524                return 0;
5525        return 1;
5526}
5527#else
5528static inline void register_as_ext2(void) { }
5529static inline void unregister_as_ext2(void) { }
5530static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5531#endif
5532
5533#if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
5534static inline void register_as_ext3(void)
5535{
5536        int err = register_filesystem(&ext3_fs_type);
5537        if (err)
5538                printk(KERN_WARNING
5539                       "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5540}
5541
5542static inline void unregister_as_ext3(void)
5543{
5544        unregister_filesystem(&ext3_fs_type);
5545}
5546
5547static inline int ext3_feature_set_ok(struct super_block *sb)
5548{
5549        if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT3_FEATURE_INCOMPAT_SUPP))
5550                return 0;
5551        if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
5552                return 0;
5553        if (sb->s_flags & MS_RDONLY)
5554                return 1;
5555        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT3_FEATURE_RO_COMPAT_SUPP))
5556                return 0;
5557        return 1;
5558}
5559#else
5560static inline void register_as_ext3(void) { }
5561static inline void unregister_as_ext3(void) { }
5562static inline int ext3_feature_set_ok(struct super_block *sb) { return 0; }
5563#endif
5564
5565static struct file_system_type ext4_fs_type = {
5566        .owner          = THIS_MODULE,
5567        .name           = "ext4",
5568        .mount          = ext4_mount,
5569        .kill_sb        = kill_block_super,
5570        .fs_flags       = FS_REQUIRES_DEV,
5571};
5572MODULE_ALIAS_FS("ext4");
5573
5574static int __init ext4_init_feat_adverts(void)
5575{
5576        struct ext4_features *ef;
5577        int ret = -ENOMEM;
5578
5579        ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
5580        if (!ef)
5581                goto out;
5582
5583        ef->f_kobj.kset = ext4_kset;
5584        init_completion(&ef->f_kobj_unregister);
5585        ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
5586                                   "features");
5587        if (ret) {
5588                kfree(ef);
5589                goto out;
5590        }
5591
5592        ext4_feat = ef;
5593        ret = 0;
5594out:
5595        return ret;
5596}
5597
5598static void ext4_exit_feat_adverts(void)
5599{
5600        kobject_put(&ext4_feat->f_kobj);
5601        wait_for_completion(&ext4_feat->f_kobj_unregister);
5602        kfree(ext4_feat);
5603}
5604
5605/* Shared across all ext4 file systems */
5606wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5607struct mutex ext4__aio_mutex[EXT4_WQ_HASH_SZ];
5608
5609static int __init ext4_init_fs(void)
5610{
5611        int i, err;
5612
5613        ext4_li_info = NULL;
5614        mutex_init(&ext4_li_mtx);
5615
5616        /* Build-time check for flags consistency */
5617        ext4_check_flag_values();
5618
5619        for (i = 0; i < EXT4_WQ_HASH_SZ; i++) {
5620                mutex_init(&ext4__aio_mutex[i]);
5621                init_waitqueue_head(&ext4__ioend_wq[i]);
5622        }
5623
5624        err = ext4_init_es();
5625        if (err)
5626                return err;
5627
5628        err = ext4_init_pageio();
5629        if (err)
5630                goto out7;
5631
5632        err = ext4_init_system_zone();
5633        if (err)
5634                goto out6;
5635        ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
5636        if (!ext4_kset) {
5637                err = -ENOMEM;
5638                goto out5;
5639        }
5640        ext4_proc_root = proc_mkdir("fs/ext4", NULL);
5641
5642        err = ext4_init_feat_adverts();
5643        if (err)
5644                goto out4;
5645
5646        err = ext4_init_mballoc();
5647        if (err)
5648                goto out2;
5649        else
5650                ext4_mballoc_ready = 1;
5651        err = init_inodecache();
5652        if (err)
5653                goto out1;
5654        register_as_ext3();
5655        register_as_ext2();
5656        err = register_filesystem(&ext4_fs_type);
5657        if (err)
5658                goto out;
5659
5660        return 0;
5661out:
5662        unregister_as_ext2();
5663        unregister_as_ext3();
5664        destroy_inodecache();
5665out1:
5666        ext4_mballoc_ready = 0;
5667        ext4_exit_mballoc();
5668out2:
5669        ext4_exit_feat_adverts();
5670out4:
5671        if (ext4_proc_root)
5672                remove_proc_entry("fs/ext4", NULL);
5673        kset_unregister(ext4_kset);
5674out5:
5675        ext4_exit_system_zone();
5676out6:
5677        ext4_exit_pageio();
5678out7:
5679        ext4_exit_es();
5680
5681        return err;
5682}
5683
5684static void __exit ext4_exit_fs(void)
5685{
5686        ext4_exit_crypto();
5687        ext4_destroy_lazyinit_thread();
5688        unregister_as_ext2();
5689        unregister_as_ext3();
5690        unregister_filesystem(&ext4_fs_type);
5691        destroy_inodecache();
5692        ext4_exit_mballoc();
5693        ext4_exit_feat_adverts();
5694        remove_proc_entry("fs/ext4", NULL);
5695        kset_unregister(ext4_kset);
5696        ext4_exit_system_zone();
5697        ext4_exit_pageio();
5698        ext4_exit_es();
5699}
5700
5701MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5702MODULE_DESCRIPTION("Fourth Extended Filesystem");
5703MODULE_LICENSE("GPL");
5704module_init(ext4_init_fs)
5705module_exit(ext4_exit_fs)
5706