fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller (davem@caip.rutgers.edu), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/cleancache.h>
  43 #include <linux/uaccess.h>
  44 #include <linux/iversion.h>
  45 #include <linux/unicode.h>
  46 #include <linux/part_stat.h>
  47 #include <linux/kthread.h>
  48 #include <linux/freezer.h>
  49
  50 #include "ext4.h"
  51 #include "ext4_extents.h"       /* Needed for trace points definition */
  52 #include "ext4_jbd2.h"
  53 #include "xattr.h"
  54 #include "acl.h"
  55 #include "mballoc.h"
  56 #include "fsmap.h"
  57
  58 #define CREATE_TRACE_POINTS
  59 #include <trace/events/ext4.h>
  60
  61 static struct ext4_lazy_init *ext4_li_info;
  62 static struct mutex ext4_li_mtx;
  63 static struct ratelimit_state ext4_mount_msg_ratelimit;
  64
  65 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  66                              unsigned long journal_devnum);
  67 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  68 static int ext4_commit_super(struct super_block *sb, int sync);
  69 static void ext4_mark_recovery_complete(struct super_block *sb,
  70                                         struct ext4_super_block *es);
  71 static void ext4_clear_journal_err(struct super_block *sb,
  72                                    struct ext4_super_block *es);
  73 static int ext4_sync_fs(struct super_block *sb, int wait);
  74 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  75 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  76 static int ext4_unfreeze(struct super_block *sb);
  77 static int ext4_freeze(struct super_block *sb);
  78 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  79                        const char *dev_name, void *data);
  80 static inline int ext2_feature_set_ok(struct super_block *sb);
  81 static inline int ext3_feature_set_ok(struct super_block *sb);
  82 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  83 static void ext4_destroy_lazyinit_thread(void);
  84 static void ext4_unregister_li_request(struct super_block *sb);
  85 static void ext4_clear_request_list(void);
  86 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  87                                             unsigned int journal_inum);
  88
  89 /*
  90  * Lock ordering
  91  *
  92  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  93  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  94  *
  95  * page fault path:
  96  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  97  *   page lock -> i_data_sem (rw)
  98  *
  99  * buffered write path:
 100  * sb_start_write -> i_mutex -> mmap_sem
 101  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 102  *   i_data_sem (rw)
 103  *
 104  * truncate:
 105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
 106  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
 107  *   i_data_sem (rw)
 108  *
 109  * direct IO:
 110  * sb_start_write -> i_mutex -> mmap_sem
 111  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 112  *
 113  * writepages:
 114  * transaction start -> page lock(s) -> i_data_sem (rw)
 115  */
 116
 117 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 118 static struct file_system_type ext2_fs_type = {
 119         .owner          = THIS_MODULE,
 120         .name           = "ext2",
 121         .mount          = ext4_mount,
 122         .kill_sb        = kill_block_super,
 123         .fs_flags       = FS_REQUIRES_DEV,
 124 };
 125 MODULE_ALIAS_FS("ext2");
 126 MODULE_ALIAS("ext2");
 127 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 128 #else
 129 #define IS_EXT2_SB(sb) (0)
 130 #endif
 131
 132
 133 static struct file_system_type ext3_fs_type = {
 134         .owner          = THIS_MODULE,
 135         .name           = "ext3",
 136         .mount          = ext4_mount,
 137         .kill_sb        = kill_block_super,
 138         .fs_flags       = FS_REQUIRES_DEV,
 139 };
 140 MODULE_ALIAS_FS("ext3");
 141 MODULE_ALIAS("ext3");
 142 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 143
 144 /*
 145  * This works like sb_bread() except it uses ERR_PTR for error
 146  * returns.  Currently with sb_bread it's impossible to distinguish
 147  * between ENOMEM and EIO situations (since both result in a NULL
 148  * return.
 149  */
 150 struct buffer_head *
 151 ext4_sb_bread(struct super_block *sb, sector_t block, int op_flags)
 152 {
 153         struct buffer_head *bh = sb_getblk(sb, block);
 154
 155         if (bh == NULL)
 156                 return ERR_PTR(-ENOMEM);
 157         if (ext4_buffer_uptodate(bh))
 158                 return bh;
 159         ll_rw_block(REQ_OP_READ, REQ_META | op_flags, 1, &bh);
 160         wait_on_buffer(bh);
 161         if (buffer_uptodate(bh))
 162                 return bh;
 163         put_bh(bh);
 164         return ERR_PTR(-EIO);
 165 }
 166
 167 static int ext4_verify_csum_type(struct super_block *sb,
 168                                  struct ext4_super_block *es)
 169 {
 170         if (!ext4_has_feature_metadata_csum(sb))
 171                 return 1;
 172
 173         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 174 }
 175
 176 static __le32 ext4_superblock_csum(struct super_block *sb,
 177                                    struct ext4_super_block *es)
 178 {
 179         struct ext4_sb_info *sbi = EXT4_SB(sb);
 180         int offset = offsetof(struct ext4_super_block, s_checksum);
 181         __u32 csum;
 182
 183         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 184
 185         return cpu_to_le32(csum);
 186 }
 187
 188 static int ext4_superblock_csum_verify(struct super_block *sb,
 189                                        struct ext4_super_block *es)
 190 {
 191         if (!ext4_has_metadata_csum(sb))
 192                 return 1;
 193
 194         return es->s_checksum == ext4_superblock_csum(sb, es);
 195 }
 196
 197 void ext4_superblock_csum_set(struct super_block *sb)
 198 {
 199         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 200
 201         if (!ext4_has_metadata_csum(sb))
 202                 return;
 203
 204         es->s_checksum = ext4_superblock_csum(sb, es);
 205 }
 206
 207 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 208                                struct ext4_group_desc *bg)
 209 {
 210         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 211                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 212                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 213 }
 214
 215 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 216                                struct ext4_group_desc *bg)
 217 {
 218         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 219                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 220                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 221 }
 222
 223 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 224                               struct ext4_group_desc *bg)
 225 {
 226         return le32_to_cpu(bg->bg_inode_table_lo) |
 227                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 228                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 229 }
 230
 231 __u32 ext4_free_group_clusters(struct super_block *sb,
 232                                struct ext4_group_desc *bg)
 233 {
 234         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 235                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 236                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 237 }
 238
 239 __u32 ext4_free_inodes_count(struct super_block *sb,
 240                               struct ext4_group_desc *bg)
 241 {
 242         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 243                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 244                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 245 }
 246
 247 __u32 ext4_used_dirs_count(struct super_block *sb,
 248                               struct ext4_group_desc *bg)
 249 {
 250         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 251                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 252                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 253 }
 254
 255 __u32 ext4_itable_unused_count(struct super_block *sb,
 256                               struct ext4_group_desc *bg)
 257 {
 258         return le16_to_cpu(bg->bg_itable_unused_lo) |
 259                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 260                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 261 }
 262
 263 void ext4_block_bitmap_set(struct super_block *sb,
 264                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 265 {
 266         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 267         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 268                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 269 }
 270
 271 void ext4_inode_bitmap_set(struct super_block *sb,
 272                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 273 {
 274         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 275         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 276                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 277 }
 278
 279 void ext4_inode_table_set(struct super_block *sb,
 280                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 281 {
 282         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 283         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 284                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 285 }
 286
 287 void ext4_free_group_clusters_set(struct super_block *sb,
 288                                   struct ext4_group_desc *bg, __u32 count)
 289 {
 290         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 291         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 292                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 293 }
 294
 295 void ext4_free_inodes_set(struct super_block *sb,
 296                           struct ext4_group_desc *bg, __u32 count)
 297 {
 298         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 299         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 300                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 301 }
 302
 303 void ext4_used_dirs_set(struct super_block *sb,
 304                           struct ext4_group_desc *bg, __u32 count)
 305 {
 306         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 307         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 308                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 309 }
 310
 311 void ext4_itable_unused_set(struct super_block *sb,
 312                           struct ext4_group_desc *bg, __u32 count)
 313 {
 314         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 315         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 316                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 317 }
 318
 319 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
 320 {
 321         time64_t now = ktime_get_real_seconds();
 322
 323         now = clamp_val(now, 0, (1ull << 40) - 1);
 324
 325         *lo = cpu_to_le32(lower_32_bits(now));
 326         *hi = upper_32_bits(now);
 327 }
 328
 329 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 330 {
 331         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 332 }
 333 #define ext4_update_tstamp(es, tstamp) \
 334         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 335 #define ext4_get_tstamp(es, tstamp) \
 336         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 337
 338 static void __save_error_info(struct super_block *sb, int error,
 339                               __u32 ino, __u64 block,
 340                               const char *func, unsigned int line)
 341 {
 342         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 343         int err;
 344
 345         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 346         if (bdev_read_only(sb->s_bdev))
 347                 return;
 348         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 349         ext4_update_tstamp(es, s_last_error_time);
 350         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 351         es->s_last_error_line = cpu_to_le32(line);
 352         es->s_last_error_ino = cpu_to_le32(ino);
 353         es->s_last_error_block = cpu_to_le64(block);
 354         switch (error) {
 355         case EIO:
 356                 err = EXT4_ERR_EIO;
 357                 break;
 358         case ENOMEM:
 359                 err = EXT4_ERR_ENOMEM;
 360                 break;
 361         case EFSBADCRC:
 362                 err = EXT4_ERR_EFSBADCRC;
 363                 break;
 364         case 0:
 365         case EFSCORRUPTED:
 366                 err = EXT4_ERR_EFSCORRUPTED;
 367                 break;
 368         case ENOSPC:
 369                 err = EXT4_ERR_ENOSPC;
 370                 break;
 371         case ENOKEY:
 372                 err = EXT4_ERR_ENOKEY;
 373                 break;
 374         case EROFS:
 375                 err = EXT4_ERR_EROFS;
 376                 break;
 377         case EFBIG:
 378                 err = EXT4_ERR_EFBIG;
 379                 break;
 380         case EEXIST:
 381                 err = EXT4_ERR_EEXIST;
 382                 break;
 383         case ERANGE:
 384                 err = EXT4_ERR_ERANGE;
 385                 break;
 386         case EOVERFLOW:
 387                 err = EXT4_ERR_EOVERFLOW;
 388                 break;
 389         case EBUSY:
 390                 err = EXT4_ERR_EBUSY;
 391                 break;
 392         case ENOTDIR:
 393                 err = EXT4_ERR_ENOTDIR;
 394                 break;
 395         case ENOTEMPTY:
 396                 err = EXT4_ERR_ENOTEMPTY;
 397                 break;
 398         case ESHUTDOWN:
 399                 err = EXT4_ERR_ESHUTDOWN;
 400                 break;
 401         case EFAULT:
 402                 err = EXT4_ERR_EFAULT;
 403                 break;
 404         default:
 405                 err = EXT4_ERR_UNKNOWN;
 406         }
 407         es->s_last_error_errcode = err;
 408         if (!es->s_first_error_time) {
 409                 es->s_first_error_time = es->s_last_error_time;
 410                 es->s_first_error_time_hi = es->s_last_error_time_hi;
 411                 strncpy(es->s_first_error_func, func,
 412                         sizeof(es->s_first_error_func));
 413                 es->s_first_error_line = cpu_to_le32(line);
 414                 es->s_first_error_ino = es->s_last_error_ino;
 415                 es->s_first_error_block = es->s_last_error_block;
 416                 es->s_first_error_errcode = es->s_last_error_errcode;
 417         }
 418         /*
 419          * Start the daily error reporting function if it hasn't been
 420          * started already
 421          */
 422         if (!es->s_error_count)
 423                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 424         le32_add_cpu(&es->s_error_count, 1);
 425 }
 426
 427 static void save_error_info(struct super_block *sb, int error,
 428                             __u32 ino, __u64 block,
 429                             const char *func, unsigned int line)
 430 {
 431         __save_error_info(sb, error, ino, block, func, line);
 432         if (!bdev_read_only(sb->s_bdev))
 433                 ext4_commit_super(sb, 1);
 434 }
 435
 436 /*
 437  * The del_gendisk() function uninitializes the disk-specific data
 438  * structures, including the bdi structure, without telling anyone
 439  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 440  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 441  * This is a kludge to prevent these oops until we can put in a proper
 442  * hook in del_gendisk() to inform the VFS and file system layers.
 443  */
 444 static int block_device_ejected(struct super_block *sb)
 445 {
 446         struct inode *bd_inode = sb->s_bdev->bd_inode;
 447         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 448
 449         return bdi->dev == NULL;
 450 }
 451
 452 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 453 {
 454         struct super_block              *sb = journal->j_private;
 455         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 456         int                             error = is_journal_aborted(journal);
 457         struct ext4_journal_cb_entry    *jce;
 458
 459         BUG_ON(txn->t_state == T_FINISHED);
 460
 461         ext4_process_freed_data(sb, txn->t_tid);
 462
 463         spin_lock(&sbi->s_md_lock);
 464         while (!list_empty(&txn->t_private_list)) {
 465                 jce = list_entry(txn->t_private_list.next,
 466                                  struct ext4_journal_cb_entry, jce_list);
 467                 list_del_init(&jce->jce_list);
 468                 spin_unlock(&sbi->s_md_lock);
 469                 jce->jce_func(sb, jce, error);
 470                 spin_lock(&sbi->s_md_lock);
 471         }
 472         spin_unlock(&sbi->s_md_lock);
 473 }
 474
 475 static bool system_going_down(void)
 476 {
 477         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 478                 || system_state == SYSTEM_RESTART;
 479 }
 480
 481 /* Deal with the reporting of failure conditions on a filesystem such as
 482  * inconsistencies detected or read IO failures.
 483  *
 484  * On ext2, we can store the error state of the filesystem in the
 485  * superblock.  That is not possible on ext4, because we may have other
 486  * write ordering constraints on the superblock which prevent us from
 487  * writing it out straight away; and given that the journal is about to
 488  * be aborted, we can't rely on the current, or future, transactions to
 489  * write out the superblock safely.
 490  *
 491  * We'll just use the jbd2_journal_abort() error code to record an error in
 492  * the journal instead.  On recovery, the journal will complain about
 493  * that error until we've noted it down and cleared it.
 494  */
 495
 496 static void ext4_handle_error(struct super_block *sb)
 497 {
 498         if (test_opt(sb, WARN_ON_ERROR))
 499                 WARN_ON_ONCE(1);
 500
 501         if (sb_rdonly(sb))
 502                 return;
 503
 504         if (!test_opt(sb, ERRORS_CONT)) {
 505                 journal_t *journal = EXT4_SB(sb)->s_journal;
 506
 507                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 508                 if (journal)
 509                         jbd2_journal_abort(journal, -EIO);
 510         }
 511         /*
 512          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 513          * could panic during 'reboot -f' as the underlying device got already
 514          * disabled.
 515          */
 516         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
 517                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 518                 /*
 519                  * Make sure updated value of ->s_mount_flags will be visible
 520                  * before ->s_flags update
 521                  */
 522                 smp_wmb();
 523                 sb->s_flags |= SB_RDONLY;
 524         } else if (test_opt(sb, ERRORS_PANIC)) {
 525                 if (EXT4_SB(sb)->s_journal &&
 526                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 527                         return;
 528                 panic("EXT4-fs (device %s): panic forced after error\n",
 529                         sb->s_id);
 530         }
 531 }
 532
 533 #define ext4_error_ratelimit(sb)                                        \
 534                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 535                              "EXT4-fs error")
 536
 537 void __ext4_error(struct super_block *sb, const char *function,
 538                   unsigned int line, int error, __u64 block,
 539                   const char *fmt, ...)
 540 {
 541         struct va_format vaf;
 542         va_list args;
 543
 544         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 545                 return;
 546
 547         trace_ext4_error(sb, function, line);
 548         if (ext4_error_ratelimit(sb)) {
 549                 va_start(args, fmt);
 550                 vaf.fmt = fmt;
 551                 vaf.va = &args;
 552                 printk(KERN_CRIT
 553                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 554                        sb->s_id, function, line, current->comm, &vaf);
 555                 va_end(args);
 556         }
 557         save_error_info(sb, error, 0, block, function, line);
 558         ext4_handle_error(sb);
 559 }
 560
 561 void __ext4_error_inode(struct inode *inode, const char *function,
 562                         unsigned int line, ext4_fsblk_t block, int error,
 563                         const char *fmt, ...)
 564 {
 565         va_list args;
 566         struct va_format vaf;
 567
 568         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 569                 return;
 570
 571         trace_ext4_error(inode->i_sb, function, line);
 572         if (ext4_error_ratelimit(inode->i_sb)) {
 573                 va_start(args, fmt);
 574                 vaf.fmt = fmt;
 575                 vaf.va = &args;
 576                 if (block)
 577                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 578                                "inode #%lu: block %llu: comm %s: %pV\n",
 579                                inode->i_sb->s_id, function, line, inode->i_ino,
 580                                block, current->comm, &vaf);
 581                 else
 582                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 583                                "inode #%lu: comm %s: %pV\n",
 584                                inode->i_sb->s_id, function, line, inode->i_ino,
 585                                current->comm, &vaf);
 586                 va_end(args);
 587         }
 588         save_error_info(inode->i_sb, error, inode->i_ino, block,
 589                         function, line);
 590         ext4_handle_error(inode->i_sb);
 591 }
 592
 593 void __ext4_error_file(struct file *file, const char *function,
 594                        unsigned int line, ext4_fsblk_t block,
 595                        const char *fmt, ...)
 596 {
 597         va_list args;
 598         struct va_format vaf;
 599         struct ext4_super_block *es;
 600         struct inode *inode = file_inode(file);
 601         char pathname[80], *path;
 602
 603         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 604                 return;
 605
 606         trace_ext4_error(inode->i_sb, function, line);
 607         es = EXT4_SB(inode->i_sb)->s_es;
 608         if (ext4_error_ratelimit(inode->i_sb)) {
 609                 path = file_path(file, pathname, sizeof(pathname));
 610                 if (IS_ERR(path))
 611                         path = "(unknown)";
 612                 va_start(args, fmt);
 613                 vaf.fmt = fmt;
 614                 vaf.va = &args;
 615                 if (block)
 616                         printk(KERN_CRIT
 617                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 618                                "block %llu: comm %s: path %s: %pV\n",
 619                                inode->i_sb->s_id, function, line, inode->i_ino,
 620                                block, current->comm, path, &vaf);
 621                 else
 622                         printk(KERN_CRIT
 623                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 624                                "comm %s: path %s: %pV\n",
 625                                inode->i_sb->s_id, function, line, inode->i_ino,
 626                                current->comm, path, &vaf);
 627                 va_end(args);
 628         }
 629         save_error_info(inode->i_sb, EFSCORRUPTED, inode->i_ino, block,
 630                         function, line);
 631         ext4_handle_error(inode->i_sb);
 632 }
 633
 634 const char *ext4_decode_error(struct super_block *sb, int errno,
 635                               char nbuf[16])
 636 {
 637         char *errstr = NULL;
 638
 639         switch (errno) {
 640         case -EFSCORRUPTED:
 641                 errstr = "Corrupt filesystem";
 642                 break;
 643         case -EFSBADCRC:
 644                 errstr = "Filesystem failed CRC";
 645                 break;
 646         case -EIO:
 647                 errstr = "IO failure";
 648                 break;
 649         case -ENOMEM:
 650                 errstr = "Out of memory";
 651                 break;
 652         case -EROFS:
 653                 if (!sb || (EXT4_SB(sb)->s_journal &&
 654                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 655                         errstr = "Journal has aborted";
 656                 else
 657                         errstr = "Readonly filesystem";
 658                 break;
 659         default:
 660                 /* If the caller passed in an extra buffer for unknown
 661                  * errors, textualise them now.  Else we just return
 662                  * NULL. */
 663                 if (nbuf) {
 664                         /* Check for truncated error codes... */
 665                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 666                                 errstr = nbuf;
 667                 }
 668                 break;
 669         }
 670
 671         return errstr;
 672 }
 673
 674 /* __ext4_std_error decodes expected errors from journaling functions
 675  * automatically and invokes the appropriate error response.  */
 676
 677 void __ext4_std_error(struct super_block *sb, const char *function,
 678                       unsigned int line, int errno)
 679 {
 680         char nbuf[16];
 681         const char *errstr;
 682
 683         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 684                 return;
 685
 686         /* Special case: if the error is EROFS, and we're not already
 687          * inside a transaction, then there's really no point in logging
 688          * an error. */
 689         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 690                 return;
 691
 692         if (ext4_error_ratelimit(sb)) {
 693                 errstr = ext4_decode_error(sb, errno, nbuf);
 694                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 695                        sb->s_id, function, line, errstr);
 696         }
 697
 698         save_error_info(sb, -errno, 0, 0, function, line);
 699         ext4_handle_error(sb);
 700 }
 701
 702 /*
 703  * ext4_abort is a much stronger failure handler than ext4_error.  The
 704  * abort function may be used to deal with unrecoverable failures such
 705  * as journal IO errors or ENOMEM at a critical moment in log management.
 706  *
 707  * We unconditionally force the filesystem into an ABORT|READONLY state,
 708  * unless the error response on the fs has been set to panic in which
 709  * case we take the easy way out and panic immediately.
 710  */
 711
 712 void __ext4_abort(struct super_block *sb, const char *function,
 713                   unsigned int line, int error, const char *fmt, ...)
 714 {
 715         struct va_format vaf;
 716         va_list args;
 717
 718         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 719                 return;
 720
 721         save_error_info(sb, error, 0, 0, function, line);
 722         va_start(args, fmt);
 723         vaf.fmt = fmt;
 724         vaf.va = &args;
 725         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 726                sb->s_id, function, line, &vaf);
 727         va_end(args);
 728
 729         if (sb_rdonly(sb) == 0) {
 730                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 731                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 732                 /*
 733                  * Make sure updated value of ->s_mount_flags will be visible
 734                  * before ->s_flags update
 735                  */
 736                 smp_wmb();
 737                 sb->s_flags |= SB_RDONLY;
 738                 if (EXT4_SB(sb)->s_journal)
 739                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 740         }
 741         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 742                 if (EXT4_SB(sb)->s_journal &&
 743                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 744                         return;
 745                 panic("EXT4-fs panic from previous error\n");
 746         }
 747 }
 748
 749 void __ext4_msg(struct super_block *sb,
 750                 const char *prefix, const char *fmt, ...)
 751 {
 752         struct va_format vaf;
 753         va_list args;
 754
 755         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 756                 return;
 757
 758         va_start(args, fmt);
 759         vaf.fmt = fmt;
 760         vaf.va = &args;
 761         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 762         va_end(args);
 763 }
 764
 765 #define ext4_warning_ratelimit(sb)                                      \
 766                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 767                              "EXT4-fs warning")
 768
 769 void __ext4_warning(struct super_block *sb, const char *function,
 770                     unsigned int line, const char *fmt, ...)
 771 {
 772         struct va_format vaf;
 773         va_list args;
 774
 775         if (!ext4_warning_ratelimit(sb))
 776                 return;
 777
 778         va_start(args, fmt);
 779         vaf.fmt = fmt;
 780         vaf.va = &args;
 781         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 782                sb->s_id, function, line, &vaf);
 783         va_end(args);
 784 }
 785
 786 void __ext4_warning_inode(const struct inode *inode, const char *function,
 787                           unsigned int line, const char *fmt, ...)
 788 {
 789         struct va_format vaf;
 790         va_list args;
 791
 792         if (!ext4_warning_ratelimit(inode->i_sb))
 793                 return;
 794
 795         va_start(args, fmt);
 796         vaf.fmt = fmt;
 797         vaf.va = &args;
 798         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 799                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 800                function, line, inode->i_ino, current->comm, &vaf);
 801         va_end(args);
 802 }
 803
 804 void __ext4_grp_locked_error(const char *function, unsigned int line,
 805                              struct super_block *sb, ext4_group_t grp,
 806                              unsigned long ino, ext4_fsblk_t block,
 807                              const char *fmt, ...)
 808 __releases(bitlock)
 809 __acquires(bitlock)
 810 {
 811         struct va_format vaf;
 812         va_list args;
 813
 814         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 815                 return;
 816
 817         trace_ext4_error(sb, function, line);
 818         __save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
 819
 820         if (ext4_error_ratelimit(sb)) {
 821                 va_start(args, fmt);
 822                 vaf.fmt = fmt;
 823                 vaf.va = &args;
 824                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 825                        sb->s_id, function, line, grp);
 826                 if (ino)
 827                         printk(KERN_CONT "inode %lu: ", ino);
 828                 if (block)
 829                         printk(KERN_CONT "block %llu:",
 830                                (unsigned long long) block);
 831                 printk(KERN_CONT "%pV\n", &vaf);
 832                 va_end(args);
 833         }
 834
 835         if (test_opt(sb, WARN_ON_ERROR))
 836                 WARN_ON_ONCE(1);
 837
 838         if (test_opt(sb, ERRORS_CONT)) {
 839                 ext4_commit_super(sb, 0);
 840                 return;
 841         }
 842
 843         ext4_unlock_group(sb, grp);
 844         ext4_commit_super(sb, 1);
 845         ext4_handle_error(sb);
 846         /*
 847          * We only get here in the ERRORS_RO case; relocking the group
 848          * may be dangerous, but nothing bad will happen since the
 849          * filesystem will have already been marked read/only and the
 850          * journal has been aborted.  We return 1 as a hint to callers
 851          * who might what to use the return value from
 852          * ext4_grp_locked_error() to distinguish between the
 853          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 854          * aggressively from the ext4 function in question, with a
 855          * more appropriate error code.
 856          */
 857         ext4_lock_group(sb, grp);
 858         return;
 859 }
 860
 861 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 862                                      ext4_group_t group,
 863                                      unsigned int flags)
 864 {
 865         struct ext4_sb_info *sbi = EXT4_SB(sb);
 866         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 867         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 868         int ret;
 869
 870         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
 871                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 872                                             &grp->bb_state);
 873                 if (!ret)
 874                         percpu_counter_sub(&sbi->s_freeclusters_counter,
 875                                            grp->bb_free);
 876         }
 877
 878         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
 879                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
 880                                             &grp->bb_state);
 881                 if (!ret && gdp) {
 882                         int count;
 883
 884                         count = ext4_free_inodes_count(sb, gdp);
 885                         percpu_counter_sub(&sbi->s_freeinodes_counter,
 886                                            count);
 887                 }
 888         }
 889 }
 890
 891 void ext4_update_dynamic_rev(struct super_block *sb)
 892 {
 893         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 894
 895         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 896                 return;
 897
 898         ext4_warning(sb,
 899                      "updating to rev %d because of new feature flag, "
 900                      "running e2fsck is recommended",
 901                      EXT4_DYNAMIC_REV);
 902
 903         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 904         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 905         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 906         /* leave es->s_feature_*compat flags alone */
 907         /* es->s_uuid will be set by e2fsck if empty */
 908
 909         /*
 910          * The rest of the superblock fields should be zero, and if not it
 911          * means they are likely already in use, so leave them alone.  We
 912          * can leave it up to e2fsck to clean up any inconsistencies there.
 913          */
 914 }
 915
 916 /*
 917  * Open the external journal device
 918  */
 919 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 920 {
 921         struct block_device *bdev;
 922
 923         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 924         if (IS_ERR(bdev))
 925                 goto fail;
 926         return bdev;
 927
 928 fail:
 929         ext4_msg(sb, KERN_ERR,
 930                  "failed to open journal device unknown-block(%u,%u) %ld",
 931                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
 932         return NULL;
 933 }
 934
 935 /*
 936  * Release the journal device
 937  */
 938 static void ext4_blkdev_put(struct block_device *bdev)
 939 {
 940         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 941 }
 942
 943 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 944 {
 945         struct block_device *bdev;
 946         bdev = sbi->journal_bdev;
 947         if (bdev) {
 948                 ext4_blkdev_put(bdev);
 949                 sbi->journal_bdev = NULL;
 950         }
 951 }
 952
 953 static inline struct inode *orphan_list_entry(struct list_head *l)
 954 {
 955         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 956 }
 957
 958 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 959 {
 960         struct list_head *l;
 961
 962         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 963                  le32_to_cpu(sbi->s_es->s_last_orphan));
 964
 965         printk(KERN_ERR "sb_info orphan list:\n");
 966         list_for_each(l, &sbi->s_orphan) {
 967                 struct inode *inode = orphan_list_entry(l);
 968                 printk(KERN_ERR "  "
 969                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 970                        inode->i_sb->s_id, inode->i_ino, inode,
 971                        inode->i_mode, inode->i_nlink,
 972                        NEXT_ORPHAN(inode));
 973         }
 974 }
 975
 976 #ifdef CONFIG_QUOTA
 977 static int ext4_quota_off(struct super_block *sb, int type);
 978
 979 static inline void ext4_quota_off_umount(struct super_block *sb)
 980 {
 981         int type;
 982
 983         /* Use our quota_off function to clear inode flags etc. */
 984         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 985                 ext4_quota_off(sb, type);
 986 }
 987
 988 /*
 989  * This is a helper function which is used in the mount/remount
 990  * codepaths (which holds s_umount) to fetch the quota file name.
 991  */
 992 static inline char *get_qf_name(struct super_block *sb,
 993                                 struct ext4_sb_info *sbi,
 994                                 int type)
 995 {
 996         return rcu_dereference_protected(sbi->s_qf_names[type],
 997                                          lockdep_is_held(&sb->s_umount));
 998 }
 999 #else
1000 static inline void ext4_quota_off_umount(struct super_block *sb)
1001 {
1002 }
1003 #endif
1004
1005 static void ext4_put_super(struct super_block *sb)
1006 {
1007         struct ext4_sb_info *sbi = EXT4_SB(sb);
1008         struct ext4_super_block *es = sbi->s_es;
1009         struct buffer_head **group_desc;
1010         struct flex_groups **flex_groups;
1011         int aborted = 0;
1012         int i, err;
1013
1014         ext4_unregister_li_request(sb);
1015         ext4_quota_off_umount(sb);
1016
1017         destroy_workqueue(sbi->rsv_conversion_wq);
1018
1019         /*
1020          * Unregister sysfs before destroying jbd2 journal.
1021          * Since we could still access attr_journal_task attribute via sysfs
1022          * path which could have sbi->s_journal->j_task as NULL
1023          */
1024         ext4_unregister_sysfs(sb);
1025
1026         if (sbi->s_journal) {
1027                 aborted = is_journal_aborted(sbi->s_journal);
1028                 err = jbd2_journal_destroy(sbi->s_journal);
1029                 sbi->s_journal = NULL;
1030                 if ((err < 0) && !aborted) {
1031                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1032                 }
1033         }
1034
1035         ext4_es_unregister_shrinker(sbi);
1036         del_timer_sync(&sbi->s_err_report);
1037         ext4_release_system_zone(sb);
1038         ext4_mb_release(sb);
1039         ext4_ext_release(sb);
1040
1041         if (!sb_rdonly(sb) && !aborted) {
1042                 ext4_clear_feature_journal_needs_recovery(sb);
1043                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1044         }
1045         if (!sb_rdonly(sb))
1046                 ext4_commit_super(sb, 1);
1047
1048         rcu_read_lock();
1049         group_desc = rcu_dereference(sbi->s_group_desc);
1050         for (i = 0; i < sbi->s_gdb_count; i++)
1051                 brelse(group_desc[i]);
1052         kvfree(group_desc);
1053         flex_groups = rcu_dereference(sbi->s_flex_groups);
1054         if (flex_groups) {
1055                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1056                         kvfree(flex_groups[i]);
1057                 kvfree(flex_groups);
1058         }
1059         rcu_read_unlock();
1060         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1061         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1062         percpu_counter_destroy(&sbi->s_dirs_counter);
1063         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1064         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1065 #ifdef CONFIG_QUOTA
1066         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1067                 kfree(get_qf_name(sb, sbi, i));
1068 #endif
1069
1070         /* Debugging code just in case the in-memory inode orphan list
1071          * isn't empty.  The on-disk one can be non-empty if we've
1072          * detected an error and taken the fs readonly, but the
1073          * in-memory list had better be clean by this point. */
1074         if (!list_empty(&sbi->s_orphan))
1075                 dump_orphan_list(sb, sbi);
1076         J_ASSERT(list_empty(&sbi->s_orphan));
1077
1078         sync_blockdev(sb->s_bdev);
1079         invalidate_bdev(sb->s_bdev);
1080         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1081                 /*
1082                  * Invalidate the journal device's buffers.  We don't want them
1083                  * floating about in memory - the physical journal device may
1084                  * hotswapped, and it breaks the `ro-after' testing code.
1085                  */
1086                 sync_blockdev(sbi->journal_bdev);
1087                 invalidate_bdev(sbi->journal_bdev);
1088                 ext4_blkdev_remove(sbi);
1089         }
1090
1091         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1092         sbi->s_ea_inode_cache = NULL;
1093
1094         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1095         sbi->s_ea_block_cache = NULL;
1096
1097         if (sbi->s_mmp_tsk)
1098                 kthread_stop(sbi->s_mmp_tsk);
1099         brelse(sbi->s_sbh);
1100         sb->s_fs_info = NULL;
1101         /*
1102          * Now that we are completely done shutting down the
1103          * superblock, we need to actually destroy the kobject.
1104          */
1105         kobject_put(&sbi->s_kobj);
1106         wait_for_completion(&sbi->s_kobj_unregister);
1107         if (sbi->s_chksum_driver)
1108                 crypto_free_shash(sbi->s_chksum_driver);
1109         kfree(sbi->s_blockgroup_lock);
1110         fs_put_dax(sbi->s_daxdev);
1111 #ifdef CONFIG_UNICODE
1112         utf8_unload(sbi->s_encoding);
1113 #endif
1114         kfree(sbi);
1115 }
1116
1117 static struct kmem_cache *ext4_inode_cachep;
1118
1119 /*
1120  * Called inside transaction, so use GFP_NOFS
1121  */
1122 static struct inode *ext4_alloc_inode(struct super_block *sb)
1123 {
1124         struct ext4_inode_info *ei;
1125
1126         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1127         if (!ei)
1128                 return NULL;
1129
1130         inode_set_iversion(&ei->vfs_inode, 1);
1131         spin_lock_init(&ei->i_raw_lock);
1132         INIT_LIST_HEAD(&ei->i_prealloc_list);
1133         spin_lock_init(&ei->i_prealloc_lock);
1134         ext4_es_init_tree(&ei->i_es_tree);
1135         rwlock_init(&ei->i_es_lock);
1136         INIT_LIST_HEAD(&ei->i_es_list);
1137         ei->i_es_all_nr = 0;
1138         ei->i_es_shk_nr = 0;
1139         ei->i_es_shrink_lblk = 0;
1140         ei->i_reserved_data_blocks = 0;
1141         spin_lock_init(&(ei->i_block_reservation_lock));
1142         ext4_init_pending_tree(&ei->i_pending_tree);
1143 #ifdef CONFIG_QUOTA
1144         ei->i_reserved_quota = 0;
1145         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1146 #endif
1147         ei->jinode = NULL;
1148         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1149         spin_lock_init(&ei->i_completed_io_lock);
1150         ei->i_sync_tid = 0;
1151         ei->i_datasync_tid = 0;
1152         atomic_set(&ei->i_unwritten, 0);
1153         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1154         return &ei->vfs_inode;
1155 }
1156
1157 static int ext4_drop_inode(struct inode *inode)
1158 {
1159         int drop = generic_drop_inode(inode);
1160
1161         if (!drop)
1162                 drop = fscrypt_drop_inode(inode);
1163
1164         trace_ext4_drop_inode(inode, drop);
1165         return drop;
1166 }
1167
1168 static void ext4_free_in_core_inode(struct inode *inode)
1169 {
1170         fscrypt_free_inode(inode);
1171         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1172 }
1173
1174 static void ext4_destroy_inode(struct inode *inode)
1175 {
1176         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1177                 ext4_msg(inode->i_sb, KERN_ERR,
1178                          "Inode %lu (%p): orphan list check failed!",
1179                          inode->i_ino, EXT4_I(inode));
1180                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1181                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1182                                 true);
1183                 dump_stack();
1184         }
1185 }
1186
1187 static void init_once(void *foo)
1188 {
1189         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1190
1191         INIT_LIST_HEAD(&ei->i_orphan);
1192         init_rwsem(&ei->xattr_sem);
1193         init_rwsem(&ei->i_data_sem);
1194         init_rwsem(&ei->i_mmap_sem);
1195         inode_init_once(&ei->vfs_inode);
1196 }
1197
1198 static int __init init_inodecache(void)
1199 {
1200         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1201                                 sizeof(struct ext4_inode_info), 0,
1202                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1203                                         SLAB_ACCOUNT),
1204                                 offsetof(struct ext4_inode_info, i_data),
1205                                 sizeof_field(struct ext4_inode_info, i_data),
1206                                 init_once);
1207         if (ext4_inode_cachep == NULL)
1208                 return -ENOMEM;
1209         return 0;
1210 }
1211
1212 static void destroy_inodecache(void)
1213 {
1214         /*
1215          * Make sure all delayed rcu free inodes are flushed before we
1216          * destroy cache.
1217          */
1218         rcu_barrier();
1219         kmem_cache_destroy(ext4_inode_cachep);
1220 }
1221
1222 void ext4_clear_inode(struct inode *inode)
1223 {
1224         invalidate_inode_buffers(inode);
1225         clear_inode(inode);
1226         ext4_discard_preallocations(inode);
1227         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1228         dquot_drop(inode);
1229         if (EXT4_I(inode)->jinode) {
1230                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1231                                                EXT4_I(inode)->jinode);
1232                 jbd2_free_inode(EXT4_I(inode)->jinode);
1233                 EXT4_I(inode)->jinode = NULL;
1234         }
1235         fscrypt_put_encryption_info(inode);
1236         fsverity_cleanup_inode(inode);
1237 }
1238
1239 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1240                                         u64 ino, u32 generation)
1241 {
1242         struct inode *inode;
1243
1244         /*
1245          * Currently we don't know the generation for parent directory, so
1246          * a generation of 0 means "accept any"
1247          */
1248         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1249         if (IS_ERR(inode))
1250                 return ERR_CAST(inode);
1251         if (generation && inode->i_generation != generation) {
1252                 iput(inode);
1253                 return ERR_PTR(-ESTALE);
1254         }
1255
1256         return inode;
1257 }
1258
1259 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1260                                         int fh_len, int fh_type)
1261 {
1262         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1263                                     ext4_nfs_get_inode);
1264 }
1265
1266 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1267                                         int fh_len, int fh_type)
1268 {
1269         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1270                                     ext4_nfs_get_inode);
1271 }
1272
1273 static int ext4_nfs_commit_metadata(struct inode *inode)
1274 {
1275         struct writeback_control wbc = {
1276                 .sync_mode = WB_SYNC_ALL
1277         };
1278
1279         trace_ext4_nfs_commit_metadata(inode);
1280         return ext4_write_inode(inode, &wbc);
1281 }
1282
1283 /*
1284  * Try to release metadata pages (indirect blocks, directories) which are
1285  * mapped via the block device.  Since these pages could have journal heads
1286  * which would prevent try_to_free_buffers() from freeing them, we must use
1287  * jbd2 layer's try_to_free_buffers() function to release them.
1288  */
1289 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1290                                  gfp_t wait)
1291 {
1292         journal_t *journal = EXT4_SB(sb)->s_journal;
1293
1294         WARN_ON(PageChecked(page));
1295         if (!page_has_buffers(page))
1296                 return 0;
1297         if (journal)
1298                 return jbd2_journal_try_to_free_buffers(journal, page,
1299                                                 wait & ~__GFP_DIRECT_RECLAIM);
1300         return try_to_free_buffers(page);
1301 }
1302
1303 #ifdef CONFIG_FS_ENCRYPTION
1304 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1305 {
1306         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1307                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1308 }
1309
1310 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1311                                                         void *fs_data)
1312 {
1313         handle_t *handle = fs_data;
1314         int res, res2, credits, retries = 0;
1315
1316         /*
1317          * Encrypting the root directory is not allowed because e2fsck expects
1318          * lost+found to exist and be unencrypted, and encrypting the root
1319          * directory would imply encrypting the lost+found directory as well as
1320          * the filename "lost+found" itself.
1321          */
1322         if (inode->i_ino == EXT4_ROOT_INO)
1323                 return -EPERM;
1324
1325         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1326                 return -EINVAL;
1327
1328         res = ext4_convert_inline_data(inode);
1329         if (res)
1330                 return res;
1331
1332         /*
1333          * If a journal handle was specified, then the encryption context is
1334          * being set on a new inode via inheritance and is part of a larger
1335          * transaction to create the inode.  Otherwise the encryption context is
1336          * being set on an existing inode in its own transaction.  Only in the
1337          * latter case should the "retry on ENOSPC" logic be used.
1338          */
1339
1340         if (handle) {
1341                 res = ext4_xattr_set_handle(handle, inode,
1342                                             EXT4_XATTR_INDEX_ENCRYPTION,
1343                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1344                                             ctx, len, 0);
1345                 if (!res) {
1346                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1347                         ext4_clear_inode_state(inode,
1348                                         EXT4_STATE_MAY_INLINE_DATA);
1349                         /*
1350                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1351                          * S_DAX may be disabled
1352                          */
1353                         ext4_set_inode_flags(inode);
1354                 }
1355                 return res;
1356         }
1357
1358         res = dquot_initialize(inode);
1359         if (res)
1360                 return res;
1361 retry:
1362         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1363                                      &credits);
1364         if (res)
1365                 return res;
1366
1367         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1368         if (IS_ERR(handle))
1369                 return PTR_ERR(handle);
1370
1371         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1372                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1373                                     ctx, len, 0);
1374         if (!res) {
1375                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1376                 /*
1377                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1378                  * S_DAX may be disabled
1379                  */
1380                 ext4_set_inode_flags(inode);
1381                 res = ext4_mark_inode_dirty(handle, inode);
1382                 if (res)
1383                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1384         }
1385         res2 = ext4_journal_stop(handle);
1386
1387         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1388                 goto retry;
1389         if (!res)
1390                 res = res2;
1391         return res;
1392 }
1393
1394 static bool ext4_dummy_context(struct inode *inode)
1395 {
1396         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1397 }
1398
1399 static bool ext4_has_stable_inodes(struct super_block *sb)
1400 {
1401         return ext4_has_feature_stable_inodes(sb);
1402 }
1403
1404 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1405                                        int *ino_bits_ret, int *lblk_bits_ret)
1406 {
1407         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1408         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1409 }
1410
1411 static const struct fscrypt_operations ext4_cryptops = {
1412         .key_prefix             = "ext4:",
1413         .get_context            = ext4_get_context,
1414         .set_context            = ext4_set_context,
1415         .dummy_context          = ext4_dummy_context,
1416         .empty_dir              = ext4_empty_dir,
1417         .max_namelen            = EXT4_NAME_LEN,
1418         .has_stable_inodes      = ext4_has_stable_inodes,
1419         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1420 };
1421 #endif
1422
1423 #ifdef CONFIG_QUOTA
1424 static const char * const quotatypes[] = INITQFNAMES;
1425 #define QTYPE2NAME(t) (quotatypes[t])
1426
1427 static int ext4_write_dquot(struct dquot *dquot);
1428 static int ext4_acquire_dquot(struct dquot *dquot);
1429 static int ext4_release_dquot(struct dquot *dquot);
1430 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1431 static int ext4_write_info(struct super_block *sb, int type);
1432 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1433                          const struct path *path);
1434 static int ext4_quota_on_mount(struct super_block *sb, int type);
1435 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1436                                size_t len, loff_t off);
1437 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1438                                 const char *data, size_t len, loff_t off);
1439 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1440                              unsigned int flags);
1441 static int ext4_enable_quotas(struct super_block *sb);
1442
1443 static struct dquot **ext4_get_dquots(struct inode *inode)
1444 {
1445         return EXT4_I(inode)->i_dquot;
1446 }
1447
1448 static const struct dquot_operations ext4_quota_operations = {
1449         .get_reserved_space     = ext4_get_reserved_space,
1450         .write_dquot            = ext4_write_dquot,
1451         .acquire_dquot          = ext4_acquire_dquot,
1452         .release_dquot          = ext4_release_dquot,
1453         .mark_dirty             = ext4_mark_dquot_dirty,
1454         .write_info             = ext4_write_info,
1455         .alloc_dquot            = dquot_alloc,
1456         .destroy_dquot          = dquot_destroy,
1457         .get_projid             = ext4_get_projid,
1458         .get_inode_usage        = ext4_get_inode_usage,
1459         .get_next_id            = dquot_get_next_id,
1460 };
1461
1462 static const struct quotactl_ops ext4_qctl_operations = {
1463         .quota_on       = ext4_quota_on,
1464         .quota_off      = ext4_quota_off,
1465         .quota_sync     = dquot_quota_sync,
1466         .get_state      = dquot_get_state,
1467         .set_info       = dquot_set_dqinfo,
1468         .get_dqblk      = dquot_get_dqblk,
1469         .set_dqblk      = dquot_set_dqblk,
1470         .get_nextdqblk  = dquot_get_next_dqblk,
1471 };
1472 #endif
1473
1474 static const struct super_operations ext4_sops = {
1475         .alloc_inode    = ext4_alloc_inode,
1476         .free_inode     = ext4_free_in_core_inode,
1477         .destroy_inode  = ext4_destroy_inode,
1478         .write_inode    = ext4_write_inode,
1479         .dirty_inode    = ext4_dirty_inode,
1480         .drop_inode     = ext4_drop_inode,
1481         .evict_inode    = ext4_evict_inode,
1482         .put_super      = ext4_put_super,
1483         .sync_fs        = ext4_sync_fs,
1484         .freeze_fs      = ext4_freeze,
1485         .unfreeze_fs    = ext4_unfreeze,
1486         .statfs         = ext4_statfs,
1487         .remount_fs     = ext4_remount,
1488         .show_options   = ext4_show_options,
1489 #ifdef CONFIG_QUOTA
1490         .quota_read     = ext4_quota_read,
1491         .quota_write    = ext4_quota_write,
1492         .get_dquots     = ext4_get_dquots,
1493 #endif
1494         .bdev_try_to_free_page = bdev_try_to_free_page,
1495 };
1496
1497 static const struct export_operations ext4_export_ops = {
1498         .fh_to_dentry = ext4_fh_to_dentry,
1499         .fh_to_parent = ext4_fh_to_parent,
1500         .get_parent = ext4_get_parent,
1501         .commit_metadata = ext4_nfs_commit_metadata,
1502 };
1503
1504 enum {
1505         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1506         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1507         Opt_nouid32, Opt_debug, Opt_removed,
1508         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1509         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1510         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1511         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1512         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1513         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1514         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1515         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1516         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1517         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1518         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1519         Opt_nowarn_on_error, Opt_mblk_io_submit,
1520         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1521         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1522         Opt_inode_readahead_blks, Opt_journal_ioprio,
1523         Opt_dioread_nolock, Opt_dioread_lock,
1524         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1525         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1526 };
1527
1528 static const match_table_t tokens = {
1529         {Opt_bsd_df, "bsddf"},
1530         {Opt_minix_df, "minixdf"},
1531         {Opt_grpid, "grpid"},
1532         {Opt_grpid, "bsdgroups"},
1533         {Opt_nogrpid, "nogrpid"},
1534         {Opt_nogrpid, "sysvgroups"},
1535         {Opt_resgid, "resgid=%u"},
1536         {Opt_resuid, "resuid=%u"},
1537         {Opt_sb, "sb=%u"},
1538         {Opt_err_cont, "errors=continue"},
1539         {Opt_err_panic, "errors=panic"},
1540         {Opt_err_ro, "errors=remount-ro"},
1541         {Opt_nouid32, "nouid32"},
1542         {Opt_debug, "debug"},
1543         {Opt_removed, "oldalloc"},
1544         {Opt_removed, "orlov"},
1545         {Opt_user_xattr, "user_xattr"},
1546         {Opt_nouser_xattr, "nouser_xattr"},
1547         {Opt_acl, "acl"},
1548         {Opt_noacl, "noacl"},
1549         {Opt_noload, "norecovery"},
1550         {Opt_noload, "noload"},
1551         {Opt_removed, "nobh"},
1552         {Opt_removed, "bh"},
1553         {Opt_commit, "commit=%u"},
1554         {Opt_min_batch_time, "min_batch_time=%u"},
1555         {Opt_max_batch_time, "max_batch_time=%u"},
1556         {Opt_journal_dev, "journal_dev=%u"},
1557         {Opt_journal_path, "journal_path=%s"},
1558         {Opt_journal_checksum, "journal_checksum"},
1559         {Opt_nojournal_checksum, "nojournal_checksum"},
1560         {Opt_journal_async_commit, "journal_async_commit"},
1561         {Opt_abort, "abort"},
1562         {Opt_data_journal, "data=journal"},
1563         {Opt_data_ordered, "data=ordered"},
1564         {Opt_data_writeback, "data=writeback"},
1565         {Opt_data_err_abort, "data_err=abort"},
1566         {Opt_data_err_ignore, "data_err=ignore"},
1567         {Opt_offusrjquota, "usrjquota="},
1568         {Opt_usrjquota, "usrjquota=%s"},
1569         {Opt_offgrpjquota, "grpjquota="},
1570         {Opt_grpjquota, "grpjquota=%s"},
1571         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1572         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1573         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1574         {Opt_grpquota, "grpquota"},
1575         {Opt_noquota, "noquota"},
1576         {Opt_quota, "quota"},
1577         {Opt_usrquota, "usrquota"},
1578         {Opt_prjquota, "prjquota"},
1579         {Opt_barrier, "barrier=%u"},
1580         {Opt_barrier, "barrier"},
1581         {Opt_nobarrier, "nobarrier"},
1582         {Opt_i_version, "i_version"},
1583         {Opt_dax, "dax"},
1584         {Opt_stripe, "stripe=%u"},
1585         {Opt_delalloc, "delalloc"},
1586         {Opt_warn_on_error, "warn_on_error"},
1587         {Opt_nowarn_on_error, "nowarn_on_error"},
1588         {Opt_lazytime, "lazytime"},
1589         {Opt_nolazytime, "nolazytime"},
1590         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1591         {Opt_nodelalloc, "nodelalloc"},
1592         {Opt_removed, "mblk_io_submit"},
1593         {Opt_removed, "nomblk_io_submit"},
1594         {Opt_block_validity, "block_validity"},
1595         {Opt_noblock_validity, "noblock_validity"},
1596         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1597         {Opt_journal_ioprio, "journal_ioprio=%u"},
1598         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1599         {Opt_auto_da_alloc, "auto_da_alloc"},
1600         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1601         {Opt_dioread_nolock, "dioread_nolock"},
1602         {Opt_dioread_lock, "nodioread_nolock"},
1603         {Opt_dioread_lock, "dioread_lock"},
1604         {Opt_discard, "discard"},
1605         {Opt_nodiscard, "nodiscard"},
1606         {Opt_init_itable, "init_itable=%u"},
1607         {Opt_init_itable, "init_itable"},
1608         {Opt_noinit_itable, "noinit_itable"},
1609         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1610         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1611         {Opt_nombcache, "nombcache"},
1612         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1613         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1614         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1615         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1616         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1617         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1618         {Opt_err, NULL},
1619 };
1620
1621 static ext4_fsblk_t get_sb_block(void **data)
1622 {
1623         ext4_fsblk_t    sb_block;
1624         char            *options = (char *) *data;
1625
1626         if (!options || strncmp(options, "sb=", 3) != 0)
1627                 return 1;       /* Default location */
1628
1629         options += 3;
1630         /* TODO: use simple_strtoll with >32bit ext4 */
1631         sb_block = simple_strtoul(options, &options, 0);
1632         if (*options && *options != ',') {
1633                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1634                        (char *) *data);
1635                 return 1;
1636         }
1637         if (*options == ',')
1638                 options++;
1639         *data = (void *) options;
1640
1641         return sb_block;
1642 }
1643
1644 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1645 static const char deprecated_msg[] =
1646         "Mount option \"%s\" will be removed by %s\n"
1647         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1648
1649 #ifdef CONFIG_QUOTA
1650 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1651 {
1652         struct ext4_sb_info *sbi = EXT4_SB(sb);
1653         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1654         int ret = -1;
1655
1656         if (sb_any_quota_loaded(sb) && !old_qname) {
1657                 ext4_msg(sb, KERN_ERR,
1658                         "Cannot change journaled "
1659                         "quota options when quota turned on");
1660                 return -1;
1661         }
1662         if (ext4_has_feature_quota(sb)) {
1663                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1664                          "ignored when QUOTA feature is enabled");
1665                 return 1;
1666         }
1667         qname = match_strdup(args);
1668         if (!qname) {
1669                 ext4_msg(sb, KERN_ERR,
1670                         "Not enough memory for storing quotafile name");
1671                 return -1;
1672         }
1673         if (old_qname) {
1674                 if (strcmp(old_qname, qname) == 0)
1675                         ret = 1;
1676                 else
1677                         ext4_msg(sb, KERN_ERR,
1678                                  "%s quota file already specified",
1679                                  QTYPE2NAME(qtype));
1680                 goto errout;
1681         }
1682         if (strchr(qname, '/')) {
1683                 ext4_msg(sb, KERN_ERR,
1684                         "quotafile must be on filesystem root");
1685                 goto errout;
1686         }
1687         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1688         set_opt(sb, QUOTA);
1689         return 1;
1690 errout:
1691         kfree(qname);
1692         return ret;
1693 }
1694
1695 static int clear_qf_name(struct super_block *sb, int qtype)
1696 {
1697
1698         struct ext4_sb_info *sbi = EXT4_SB(sb);
1699         char *old_qname = get_qf_name(sb, sbi, qtype);
1700
1701         if (sb_any_quota_loaded(sb) && old_qname) {
1702                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1703                         " when quota turned on");
1704                 return -1;
1705         }
1706         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1707         synchronize_rcu();
1708         kfree(old_qname);
1709         return 1;
1710 }
1711 #endif
1712
1713 #define MOPT_SET        0x0001
1714 #define MOPT_CLEAR      0x0002
1715 #define MOPT_NOSUPPORT  0x0004
1716 #define MOPT_EXPLICIT   0x0008
1717 #define MOPT_CLEAR_ERR  0x0010
1718 #define MOPT_GTE0       0x0020
1719 #ifdef CONFIG_QUOTA
1720 #define MOPT_Q          0
1721 #define MOPT_QFMT       0x0040
1722 #else
1723 #define MOPT_Q          MOPT_NOSUPPORT
1724 #define MOPT_QFMT       MOPT_NOSUPPORT
1725 #endif
1726 #define MOPT_DATAJ      0x0080
1727 #define MOPT_NO_EXT2    0x0100
1728 #define MOPT_NO_EXT3    0x0200
1729 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1730 #define MOPT_STRING     0x0400
1731
1732 static const struct mount_opts {
1733         int     token;
1734         int     mount_opt;
1735         int     flags;
1736 } ext4_mount_opts[] = {
1737         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1738         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1739         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1740         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1741         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1742         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1743         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1744          MOPT_EXT4_ONLY | MOPT_SET},
1745         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1746          MOPT_EXT4_ONLY | MOPT_CLEAR},
1747         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1748         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1749         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1750          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1751         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1752          MOPT_EXT4_ONLY | MOPT_CLEAR},
1753         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1754         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1755         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1756          MOPT_EXT4_ONLY | MOPT_CLEAR},
1757         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1758          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1759         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1760                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1761          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1762         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1763         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1764         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1765         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1766         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1767          MOPT_NO_EXT2},
1768         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1769          MOPT_NO_EXT2},
1770         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1771         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1772         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1773         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1774         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1775         {Opt_commit, 0, MOPT_GTE0},
1776         {Opt_max_batch_time, 0, MOPT_GTE0},
1777         {Opt_min_batch_time, 0, MOPT_GTE0},
1778         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1779         {Opt_init_itable, 0, MOPT_GTE0},
1780         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1781         {Opt_stripe, 0, MOPT_GTE0},
1782         {Opt_resuid, 0, MOPT_GTE0},
1783         {Opt_resgid, 0, MOPT_GTE0},
1784         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1785         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1786         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1787         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1788         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1789         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1790          MOPT_NO_EXT2 | MOPT_DATAJ},
1791         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1792         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1793 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1794         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1795         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1796 #else
1797         {Opt_acl, 0, MOPT_NOSUPPORT},
1798         {Opt_noacl, 0, MOPT_NOSUPPORT},
1799 #endif
1800         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1801         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1802         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1803         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1804         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1805                                                         MOPT_SET | MOPT_Q},
1806         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1807                                                         MOPT_SET | MOPT_Q},
1808         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1809                                                         MOPT_SET | MOPT_Q},
1810         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1811                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1812                                                         MOPT_CLEAR | MOPT_Q},
1813         {Opt_usrjquota, 0, MOPT_Q},
1814         {Opt_grpjquota, 0, MOPT_Q},
1815         {Opt_offusrjquota, 0, MOPT_Q},
1816         {Opt_offgrpjquota, 0, MOPT_Q},
1817         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1818         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1819         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1820         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1821         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1822         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1823         {Opt_err, 0, 0}
1824 };
1825
1826 #ifdef CONFIG_UNICODE
1827 static const struct ext4_sb_encodings {
1828         __u16 magic;
1829         char *name;
1830         char *version;
1831 } ext4_sb_encoding_map[] = {
1832         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1833 };
1834
1835 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1836                                  const struct ext4_sb_encodings **encoding,
1837                                  __u16 *flags)
1838 {
1839         __u16 magic = le16_to_cpu(es->s_encoding);
1840         int i;
1841
1842         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1843                 if (magic == ext4_sb_encoding_map[i].magic)
1844                         break;
1845
1846         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1847                 return -EINVAL;
1848
1849         *encoding = &ext4_sb_encoding_map[i];
1850         *flags = le16_to_cpu(es->s_encoding_flags);
1851
1852         return 0;
1853 }
1854 #endif
1855
1856 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1857                             substring_t *args, unsigned long *journal_devnum,
1858                             unsigned int *journal_ioprio, int is_remount)
1859 {
1860         struct ext4_sb_info *sbi = EXT4_SB(sb);
1861         const struct mount_opts *m;
1862         kuid_t uid;
1863         kgid_t gid;
1864         int arg = 0;
1865
1866 #ifdef CONFIG_QUOTA
1867         if (token == Opt_usrjquota)
1868                 return set_qf_name(sb, USRQUOTA, &args[0]);
1869         else if (token == Opt_grpjquota)
1870                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1871         else if (token == Opt_offusrjquota)
1872                 return clear_qf_name(sb, USRQUOTA);
1873         else if (token == Opt_offgrpjquota)
1874                 return clear_qf_name(sb, GRPQUOTA);
1875 #endif
1876         switch (token) {
1877         case Opt_noacl:
1878         case Opt_nouser_xattr:
1879                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1880                 break;
1881         case Opt_sb:
1882                 return 1;       /* handled by get_sb_block() */
1883         case Opt_removed:
1884                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1885                 return 1;
1886         case Opt_abort:
1887                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1888                 return 1;
1889         case Opt_i_version:
1890                 sb->s_flags |= SB_I_VERSION;
1891                 return 1;
1892         case Opt_lazytime:
1893                 sb->s_flags |= SB_LAZYTIME;
1894                 return 1;
1895         case Opt_nolazytime:
1896                 sb->s_flags &= ~SB_LAZYTIME;
1897                 return 1;
1898         }
1899
1900         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1901                 if (token == m->token)
1902                         break;
1903
1904         if (m->token == Opt_err) {
1905                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1906                          "or missing value", opt);
1907                 return -1;
1908         }
1909
1910         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1911                 ext4_msg(sb, KERN_ERR,
1912                          "Mount option \"%s\" incompatible with ext2", opt);
1913                 return -1;
1914         }
1915         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1916                 ext4_msg(sb, KERN_ERR,
1917                          "Mount option \"%s\" incompatible with ext3", opt);
1918                 return -1;
1919         }
1920
1921         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1922                 return -1;
1923         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1924                 return -1;
1925         if (m->flags & MOPT_EXPLICIT) {
1926                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1927                         set_opt2(sb, EXPLICIT_DELALLOC);
1928                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1929                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1930                 } else
1931                         return -1;
1932         }
1933         if (m->flags & MOPT_CLEAR_ERR)
1934                 clear_opt(sb, ERRORS_MASK);
1935         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1936                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1937                          "options when quota turned on");
1938                 return -1;
1939         }
1940
1941         if (m->flags & MOPT_NOSUPPORT) {
1942                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1943         } else if (token == Opt_commit) {
1944                 if (arg == 0)
1945                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1946                 else if (arg > INT_MAX / HZ) {
1947                         ext4_msg(sb, KERN_ERR,
1948                                  "Invalid commit interval %d, "
1949                                  "must be smaller than %d",
1950                                  arg, INT_MAX / HZ);
1951                         return -1;
1952                 }
1953                 sbi->s_commit_interval = HZ * arg;
1954         } else if (token == Opt_debug_want_extra_isize) {
1955                 if ((arg & 1) ||
1956                     (arg < 4) ||
1957                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
1958                         ext4_msg(sb, KERN_ERR,
1959                                  "Invalid want_extra_isize %d", arg);
1960                         return -1;
1961                 }
1962                 sbi->s_want_extra_isize = arg;
1963         } else if (token == Opt_max_batch_time) {
1964                 sbi->s_max_batch_time = arg;
1965         } else if (token == Opt_min_batch_time) {
1966                 sbi->s_min_batch_time = arg;
1967         } else if (token == Opt_inode_readahead_blks) {
1968                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1969                         ext4_msg(sb, KERN_ERR,
1970                                  "EXT4-fs: inode_readahead_blks must be "
1971                                  "0 or a power of 2 smaller than 2^31");
1972                         return -1;
1973                 }
1974                 sbi->s_inode_readahead_blks = arg;
1975         } else if (token == Opt_init_itable) {
1976                 set_opt(sb, INIT_INODE_TABLE);
1977                 if (!args->from)
1978                         arg = EXT4_DEF_LI_WAIT_MULT;
1979                 sbi->s_li_wait_mult = arg;
1980         } else if (token == Opt_max_dir_size_kb) {
1981                 sbi->s_max_dir_size_kb = arg;
1982         } else if (token == Opt_stripe) {
1983                 sbi->s_stripe = arg;
1984         } else if (token == Opt_resuid) {
1985                 uid = make_kuid(current_user_ns(), arg);
1986                 if (!uid_valid(uid)) {
1987                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1988                         return -1;
1989                 }
1990                 sbi->s_resuid = uid;
1991         } else if (token == Opt_resgid) {
1992                 gid = make_kgid(current_user_ns(), arg);
1993                 if (!gid_valid(gid)) {
1994                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1995                         return -1;
1996                 }
1997                 sbi->s_resgid = gid;
1998         } else if (token == Opt_journal_dev) {
1999                 if (is_remount) {
2000                         ext4_msg(sb, KERN_ERR,
2001                                  "Cannot specify journal on remount");
2002                         return -1;
2003                 }
2004                 *journal_devnum = arg;
2005         } else if (token == Opt_journal_path) {
2006                 char *journal_path;
2007                 struct inode *journal_inode;
2008                 struct path path;
2009                 int error;
2010
2011                 if (is_remount) {
2012                         ext4_msg(sb, KERN_ERR,
2013                                  "Cannot specify journal on remount");
2014                         return -1;
2015                 }
2016                 journal_path = match_strdup(&args[0]);
2017                 if (!journal_path) {
2018                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2019                                 "journal device string");
2020                         return -1;
2021                 }
2022
2023                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2024                 if (error) {
2025                         ext4_msg(sb, KERN_ERR, "error: could not find "
2026                                 "journal device path: error %d", error);
2027                         kfree(journal_path);
2028                         return -1;
2029                 }
2030
2031                 journal_inode = d_inode(path.dentry);
2032                 if (!S_ISBLK(journal_inode->i_mode)) {
2033                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2034                                 "is not a block device", journal_path);
2035                         path_put(&path);
2036                         kfree(journal_path);
2037                         return -1;
2038                 }
2039
2040                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
2041                 path_put(&path);
2042                 kfree(journal_path);
2043         } else if (token == Opt_journal_ioprio) {
2044                 if (arg > 7) {
2045                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2046                                  " (must be 0-7)");
2047                         return -1;
2048                 }
2049                 *journal_ioprio =
2050                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2051         } else if (token == Opt_test_dummy_encryption) {
2052 #ifdef CONFIG_FS_ENCRYPTION
2053                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
2054                 ext4_msg(sb, KERN_WARNING,
2055                          "Test dummy encryption mode enabled");
2056 #else
2057                 ext4_msg(sb, KERN_WARNING,
2058                          "Test dummy encryption mount option ignored");
2059 #endif
2060         } else if (m->flags & MOPT_DATAJ) {
2061                 if (is_remount) {
2062                         if (!sbi->s_journal)
2063                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2064                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2065                                 ext4_msg(sb, KERN_ERR,
2066                                          "Cannot change data mode on remount");
2067                                 return -1;
2068                         }
2069                 } else {
2070                         clear_opt(sb, DATA_FLAGS);
2071                         sbi->s_mount_opt |= m->mount_opt;
2072                 }
2073 #ifdef CONFIG_QUOTA
2074         } else if (m->flags & MOPT_QFMT) {
2075                 if (sb_any_quota_loaded(sb) &&
2076                     sbi->s_jquota_fmt != m->mount_opt) {
2077                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2078                                  "quota options when quota turned on");
2079                         return -1;
2080                 }
2081                 if (ext4_has_feature_quota(sb)) {
2082                         ext4_msg(sb, KERN_INFO,
2083                                  "Quota format mount options ignored "
2084                                  "when QUOTA feature is enabled");
2085                         return 1;
2086                 }
2087                 sbi->s_jquota_fmt = m->mount_opt;
2088 #endif
2089         } else if (token == Opt_dax) {
2090 #ifdef CONFIG_FS_DAX
2091                 ext4_msg(sb, KERN_WARNING,
2092                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2093                 sbi->s_mount_opt |= m->mount_opt;
2094 #else
2095                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2096                 return -1;
2097 #endif
2098         } else if (token == Opt_data_err_abort) {
2099                 sbi->s_mount_opt |= m->mount_opt;
2100         } else if (token == Opt_data_err_ignore) {
2101                 sbi->s_mount_opt &= ~m->mount_opt;
2102         } else {
2103                 if (!args->from)
2104                         arg = 1;
2105                 if (m->flags & MOPT_CLEAR)
2106                         arg = !arg;
2107                 else if (unlikely(!(m->flags & MOPT_SET))) {
2108                         ext4_msg(sb, KERN_WARNING,
2109                                  "buggy handling of option %s", opt);
2110                         WARN_ON(1);
2111                         return -1;
2112                 }
2113                 if (arg != 0)
2114                         sbi->s_mount_opt |= m->mount_opt;
2115                 else
2116                         sbi->s_mount_opt &= ~m->mount_opt;
2117         }
2118         return 1;
2119 }
2120
2121 static int parse_options(char *options, struct super_block *sb,
2122                          unsigned long *journal_devnum,
2123                          unsigned int *journal_ioprio,
2124                          int is_remount)
2125 {
2126         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2127         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2128         substring_t args[MAX_OPT_ARGS];
2129         int token;
2130
2131         if (!options)
2132                 return 1;
2133
2134         while ((p = strsep(&options, ",")) != NULL) {
2135                 if (!*p)
2136                         continue;
2137                 /*
2138                  * Initialize args struct so we know whether arg was
2139                  * found; some options take optional arguments.
2140                  */
2141                 args[0].to = args[0].from = NULL;
2142                 token = match_token(p, tokens, args);
2143                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2144                                      journal_ioprio, is_remount) < 0)
2145                         return 0;
2146         }
2147 #ifdef CONFIG_QUOTA
2148         /*
2149          * We do the test below only for project quotas. 'usrquota' and
2150          * 'grpquota' mount options are allowed even without quota feature
2151          * to support legacy quotas in quota files.
2152          */
2153         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2154                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2155                          "Cannot enable project quota enforcement.");
2156                 return 0;
2157         }
2158         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2159         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2160         if (usr_qf_name || grp_qf_name) {
2161                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2162                         clear_opt(sb, USRQUOTA);
2163
2164                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2165                         clear_opt(sb, GRPQUOTA);
2166
2167                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2168                         ext4_msg(sb, KERN_ERR, "old and new quota "
2169                                         "format mixing");
2170                         return 0;
2171                 }
2172
2173                 if (!sbi->s_jquota_fmt) {
2174                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2175                                         "not specified");
2176                         return 0;
2177                 }
2178         }
2179 #endif
2180         if (test_opt(sb, DIOREAD_NOLOCK)) {
2181                 int blocksize =
2182                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2183                 if (blocksize < PAGE_SIZE)
2184                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2185                                  "experimental mount option 'dioread_nolock' "
2186                                  "for blocksize < PAGE_SIZE");
2187         }
2188         return 1;
2189 }
2190
2191 static inline void ext4_show_quota_options(struct seq_file *seq,
2192                                            struct super_block *sb)
2193 {
2194 #if defined(CONFIG_QUOTA)
2195         struct ext4_sb_info *sbi = EXT4_SB(sb);
2196         char *usr_qf_name, *grp_qf_name;
2197
2198         if (sbi->s_jquota_fmt) {
2199                 char *fmtname = "";
2200
2201                 switch (sbi->s_jquota_fmt) {
2202                 case QFMT_VFS_OLD:
2203                         fmtname = "vfsold";
2204                         break;
2205                 case QFMT_VFS_V0:
2206                         fmtname = "vfsv0";
2207                         break;
2208                 case QFMT_VFS_V1:
2209                         fmtname = "vfsv1";
2210                         break;
2211                 }
2212                 seq_printf(seq, ",jqfmt=%s", fmtname);
2213         }
2214
2215         rcu_read_lock();
2216         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2217         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2218         if (usr_qf_name)
2219                 seq_show_option(seq, "usrjquota", usr_qf_name);
2220         if (grp_qf_name)
2221                 seq_show_option(seq, "grpjquota", grp_qf_name);
2222         rcu_read_unlock();
2223 #endif
2224 }
2225
2226 static const char *token2str(int token)
2227 {
2228         const struct match_token *t;
2229
2230         for (t = tokens; t->token != Opt_err; t++)
2231                 if (t->token == token && !strchr(t->pattern, '='))
2232                         break;
2233         return t->pattern;
2234 }
2235
2236 /*
2237  * Show an option if
2238  *  - it's set to a non-default value OR
2239  *  - if the per-sb default is different from the global default
2240  */
2241 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2242                               int nodefs)
2243 {
2244         struct ext4_sb_info *sbi = EXT4_SB(sb);
2245         struct ext4_super_block *es = sbi->s_es;
2246         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2247         const struct mount_opts *m;
2248         char sep = nodefs ? '\n' : ',';
2249
2250 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2251 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2252
2253         if (sbi->s_sb_block != 1)
2254                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2255
2256         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2257                 int want_set = m->flags & MOPT_SET;
2258                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2259                     (m->flags & MOPT_CLEAR_ERR))
2260                         continue;
2261                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2262                         continue; /* skip if same as the default */
2263                 if ((want_set &&
2264                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2265                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2266                         continue; /* select Opt_noFoo vs Opt_Foo */
2267                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2268         }
2269
2270         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2271             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2272                 SEQ_OPTS_PRINT("resuid=%u",
2273                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2274         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2275             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2276                 SEQ_OPTS_PRINT("resgid=%u",
2277                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2278         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2279         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2280                 SEQ_OPTS_PUTS("errors=remount-ro");
2281         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2282                 SEQ_OPTS_PUTS("errors=continue");
2283         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2284                 SEQ_OPTS_PUTS("errors=panic");
2285         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2286                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2287         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2288                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2289         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2290                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2291         if (sb->s_flags & SB_I_VERSION)
2292                 SEQ_OPTS_PUTS("i_version");
2293         if (nodefs || sbi->s_stripe)
2294                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2295         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2296                         (sbi->s_mount_opt ^ def_mount_opt)) {
2297                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2298                         SEQ_OPTS_PUTS("data=journal");
2299                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2300                         SEQ_OPTS_PUTS("data=ordered");
2301                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2302                         SEQ_OPTS_PUTS("data=writeback");
2303         }
2304         if (nodefs ||
2305             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2306                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2307                                sbi->s_inode_readahead_blks);
2308
2309         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2310                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2311                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2312         if (nodefs || sbi->s_max_dir_size_kb)
2313                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2314         if (test_opt(sb, DATA_ERR_ABORT))
2315                 SEQ_OPTS_PUTS("data_err=abort");
2316         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2317                 SEQ_OPTS_PUTS("test_dummy_encryption");
2318
2319         ext4_show_quota_options(seq, sb);
2320         return 0;
2321 }
2322
2323 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2324 {
2325         return _ext4_show_options(seq, root->d_sb, 0);
2326 }
2327
2328 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2329 {
2330         struct super_block *sb = seq->private;
2331         int rc;
2332
2333         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2334         rc = _ext4_show_options(seq, sb, 1);
2335         seq_puts(seq, "\n");
2336         return rc;
2337 }
2338
2339 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2340                             int read_only)
2341 {
2342         struct ext4_sb_info *sbi = EXT4_SB(sb);
2343         int err = 0;
2344
2345         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2346                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2347                          "forcing read-only mode");
2348                 err = -EROFS;
2349         }
2350         if (read_only)
2351                 goto done;
2352         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2353                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2354                          "running e2fsck is recommended");
2355         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2356                 ext4_msg(sb, KERN_WARNING,
2357                          "warning: mounting fs with errors, "
2358                          "running e2fsck is recommended");
2359         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2360                  le16_to_cpu(es->s_mnt_count) >=
2361                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2362                 ext4_msg(sb, KERN_WARNING,
2363                          "warning: maximal mount count reached, "
2364                          "running e2fsck is recommended");
2365         else if (le32_to_cpu(es->s_checkinterval) &&
2366                  (ext4_get_tstamp(es, s_lastcheck) +
2367                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2368                 ext4_msg(sb, KERN_WARNING,
2369                          "warning: checktime reached, "
2370                          "running e2fsck is recommended");
2371         if (!sbi->s_journal)
2372                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2373         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2374                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2375         le16_add_cpu(&es->s_mnt_count, 1);
2376         ext4_update_tstamp(es, s_mtime);
2377         if (sbi->s_journal)
2378                 ext4_set_feature_journal_needs_recovery(sb);
2379
2380         err = ext4_commit_super(sb, 1);
2381 done:
2382         if (test_opt(sb, DEBUG))
2383                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2384                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2385                         sb->s_blocksize,
2386                         sbi->s_groups_count,
2387                         EXT4_BLOCKS_PER_GROUP(sb),
2388                         EXT4_INODES_PER_GROUP(sb),
2389                         sbi->s_mount_opt, sbi->s_mount_opt2);
2390
2391         cleancache_init_fs(sb);
2392         return err;
2393 }
2394
2395 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2396 {
2397         struct ext4_sb_info *sbi = EXT4_SB(sb);
2398         struct flex_groups **old_groups, **new_groups;
2399         int size, i, j;
2400
2401         if (!sbi->s_log_groups_per_flex)
2402                 return 0;
2403
2404         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2405         if (size <= sbi->s_flex_groups_allocated)
2406                 return 0;
2407
2408         new_groups = kvzalloc(roundup_pow_of_two(size *
2409                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2410         if (!new_groups) {
2411                 ext4_msg(sb, KERN_ERR,
2412                          "not enough memory for %d flex group pointers", size);
2413                 return -ENOMEM;
2414         }
2415         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2416                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2417                                          sizeof(struct flex_groups)),
2418                                          GFP_KERNEL);
2419                 if (!new_groups[i]) {
2420                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2421                                 kvfree(new_groups[j]);
2422                         kvfree(new_groups);
2423                         ext4_msg(sb, KERN_ERR,
2424                                  "not enough memory for %d flex groups", size);
2425                         return -ENOMEM;
2426                 }
2427         }
2428         rcu_read_lock();
2429         old_groups = rcu_dereference(sbi->s_flex_groups);
2430         if (old_groups)
2431                 memcpy(new_groups, old_groups,
2432                        (sbi->s_flex_groups_allocated *
2433                         sizeof(struct flex_groups *)));
2434         rcu_read_unlock();
2435         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2436         sbi->s_flex_groups_allocated = size;
2437         if (old_groups)
2438                 ext4_kvfree_array_rcu(old_groups);
2439         return 0;
2440 }
2441
2442 static int ext4_fill_flex_info(struct super_block *sb)
2443 {
2444         struct ext4_sb_info *sbi = EXT4_SB(sb);
2445         struct ext4_group_desc *gdp = NULL;
2446         struct flex_groups *fg;
2447         ext4_group_t flex_group;
2448         int i, err;
2449
2450         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2451         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2452                 sbi->s_log_groups_per_flex = 0;
2453                 return 1;
2454         }
2455
2456         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2457         if (err)
2458                 goto failed;
2459
2460         for (i = 0; i < sbi->s_groups_count; i++) {
2461                 gdp = ext4_get_group_desc(sb, i, NULL);
2462
2463                 flex_group = ext4_flex_group(sbi, i);
2464                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2465                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2466                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2467                              &fg->free_clusters);
2468                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2469         }
2470
2471         return 1;
2472 failed:
2473         return 0;
2474 }
2475
2476 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2477                                    struct ext4_group_desc *gdp)
2478 {
2479         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2480         __u16 crc = 0;
2481         __le32 le_group = cpu_to_le32(block_group);
2482         struct ext4_sb_info *sbi = EXT4_SB(sb);
2483
2484         if (ext4_has_metadata_csum(sbi->s_sb)) {
2485                 /* Use new metadata_csum algorithm */
2486                 __u32 csum32;
2487                 __u16 dummy_csum = 0;
2488
2489                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2490                                      sizeof(le_group));
2491                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2492                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2493                                      sizeof(dummy_csum));
2494                 offset += sizeof(dummy_csum);
2495                 if (offset < sbi->s_desc_size)
2496                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2497                                              sbi->s_desc_size - offset);
2498
2499                 crc = csum32 & 0xFFFF;
2500                 goto out;
2501         }
2502
2503         /* old crc16 code */
2504         if (!ext4_has_feature_gdt_csum(sb))
2505                 return 0;
2506
2507         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2508         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2509         crc = crc16(crc, (__u8 *)gdp, offset);
2510         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2511         /* for checksum of struct ext4_group_desc do the rest...*/
2512         if (ext4_has_feature_64bit(sb) &&
2513             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2514                 crc = crc16(crc, (__u8 *)gdp + offset,
2515                             le16_to_cpu(sbi->s_es->s_desc_size) -
2516                                 offset);
2517
2518 out:
2519         return cpu_to_le16(crc);
2520 }
2521
2522 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2523                                 struct ext4_group_desc *gdp)
2524 {
2525         if (ext4_has_group_desc_csum(sb) &&
2526             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2527                 return 0;
2528
2529         return 1;
2530 }
2531
2532 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2533                               struct ext4_group_desc *gdp)
2534 {
2535         if (!ext4_has_group_desc_csum(sb))
2536                 return;
2537         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2538 }
2539
2540 /* Called at mount-time, super-block is locked */
2541 static int ext4_check_descriptors(struct super_block *sb,
2542                                   ext4_fsblk_t sb_block,
2543                                   ext4_group_t *first_not_zeroed)
2544 {
2545         struct ext4_sb_info *sbi = EXT4_SB(sb);
2546         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2547         ext4_fsblk_t last_block;
2548         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2549         ext4_fsblk_t block_bitmap;
2550         ext4_fsblk_t inode_bitmap;
2551         ext4_fsblk_t inode_table;
2552         int flexbg_flag = 0;
2553         ext4_group_t i, grp = sbi->s_groups_count;
2554
2555         if (ext4_has_feature_flex_bg(sb))
2556                 flexbg_flag = 1;
2557
2558         ext4_debug("Checking group descriptors");
2559
2560         for (i = 0; i < sbi->s_groups_count; i++) {
2561                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2562
2563                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2564                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2565                 else
2566                         last_block = first_block +
2567                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2568
2569                 if ((grp == sbi->s_groups_count) &&
2570                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2571                         grp = i;
2572
2573                 block_bitmap = ext4_block_bitmap(sb, gdp);
2574                 if (block_bitmap == sb_block) {
2575                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2576                                  "Block bitmap for group %u overlaps "
2577                                  "superblock", i);
2578                         if (!sb_rdonly(sb))
2579                                 return 0;
2580                 }
2581                 if (block_bitmap >= sb_block + 1 &&
2582                     block_bitmap <= last_bg_block) {
2583                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2584                                  "Block bitmap for group %u overlaps "
2585                                  "block group descriptors", i);
2586                         if (!sb_rdonly(sb))
2587                                 return 0;
2588                 }
2589                 if (block_bitmap < first_block || block_bitmap > last_block) {
2590                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2591                                "Block bitmap for group %u not in group "
2592                                "(block %llu)!", i, block_bitmap);
2593                         return 0;
2594                 }
2595                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2596                 if (inode_bitmap == sb_block) {
2597                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2598                                  "Inode bitmap for group %u overlaps "
2599                                  "superblock", i);
2600                         if (!sb_rdonly(sb))
2601                                 return 0;
2602                 }
2603                 if (inode_bitmap >= sb_block + 1 &&
2604                     inode_bitmap <= last_bg_block) {
2605                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2606                                  "Inode bitmap for group %u overlaps "
2607                                  "block group descriptors", i);
2608                         if (!sb_rdonly(sb))
2609                                 return 0;
2610                 }
2611                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2612                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2613                                "Inode bitmap for group %u not in group "
2614                                "(block %llu)!", i, inode_bitmap);
2615                         return 0;
2616                 }
2617                 inode_table = ext4_inode_table(sb, gdp);
2618                 if (inode_table == sb_block) {
2619                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2620                                  "Inode table for group %u overlaps "
2621                                  "superblock", i);
2622                         if (!sb_rdonly(sb))
2623                                 return 0;
2624                 }
2625                 if (inode_table >= sb_block + 1 &&
2626                     inode_table <= last_bg_block) {
2627                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2628                                  "Inode table for group %u overlaps "
2629                                  "block group descriptors", i);
2630                         if (!sb_rdonly(sb))
2631                                 return 0;
2632                 }
2633                 if (inode_table < first_block ||
2634                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2635                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2636                                "Inode table for group %u not in group "
2637                                "(block %llu)!", i, inode_table);
2638                         return 0;
2639                 }
2640                 ext4_lock_group(sb, i);
2641                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2642                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2643                                  "Checksum for group %u failed (%u!=%u)",
2644                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2645                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2646                         if (!sb_rdonly(sb)) {
2647                                 ext4_unlock_group(sb, i);
2648                                 return 0;
2649                         }
2650                 }
2651                 ext4_unlock_group(sb, i);
2652                 if (!flexbg_flag)
2653                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2654         }
2655         if (NULL != first_not_zeroed)
2656                 *first_not_zeroed = grp;
2657         return 1;
2658 }
2659
2660 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2661  * the superblock) which were deleted from all directories, but held open by
2662  * a process at the time of a crash.  We walk the list and try to delete these
2663  * inodes at recovery time (only with a read-write filesystem).
2664  *
2665  * In order to keep the orphan inode chain consistent during traversal (in
2666  * case of crash during recovery), we link each inode into the superblock
2667  * orphan list_head and handle it the same way as an inode deletion during
2668  * normal operation (which journals the operations for us).
2669  *
2670  * We only do an iget() and an iput() on each inode, which is very safe if we
2671  * accidentally point at an in-use or already deleted inode.  The worst that
2672  * can happen in this case is that we get a "bit already cleared" message from
2673  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2674  * e2fsck was run on this filesystem, and it must have already done the orphan
2675  * inode cleanup for us, so we can safely abort without any further action.
2676  */
2677 static void ext4_orphan_cleanup(struct super_block *sb,
2678                                 struct ext4_super_block *es)
2679 {
2680         unsigned int s_flags = sb->s_flags;
2681         int ret, nr_orphans = 0, nr_truncates = 0;
2682 #ifdef CONFIG_QUOTA
2683         int quota_update = 0;
2684         int i;
2685 #endif
2686         if (!es->s_last_orphan) {
2687                 jbd_debug(4, "no orphan inodes to clean up\n");
2688                 return;
2689         }
2690
2691         if (bdev_read_only(sb->s_bdev)) {
2692                 ext4_msg(sb, KERN_ERR, "write access "
2693                         "unavailable, skipping orphan cleanup");
2694                 return;
2695         }
2696
2697         /* Check if feature set would not allow a r/w mount */
2698         if (!ext4_feature_set_ok(sb, 0)) {
2699                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2700                          "unknown ROCOMPAT features");
2701                 return;
2702         }
2703
2704         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2705                 /* don't clear list on RO mount w/ errors */
2706                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2707                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2708                                   "clearing orphan list.\n");
2709                         es->s_last_orphan = 0;
2710                 }
2711                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2712                 return;
2713         }
2714
2715         if (s_flags & SB_RDONLY) {
2716                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2717                 sb->s_flags &= ~SB_RDONLY;
2718         }
2719 #ifdef CONFIG_QUOTA
2720         /* Needed for iput() to work correctly and not trash data */
2721         sb->s_flags |= SB_ACTIVE;
2722
2723         /*
2724          * Turn on quotas which were not enabled for read-only mounts if
2725          * filesystem has quota feature, so that they are updated correctly.
2726          */
2727         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2728                 int ret = ext4_enable_quotas(sb);
2729
2730                 if (!ret)
2731                         quota_update = 1;
2732                 else
2733                         ext4_msg(sb, KERN_ERR,
2734                                 "Cannot turn on quotas: error %d", ret);
2735         }
2736
2737         /* Turn on journaled quotas used for old sytle */
2738         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2739                 if (EXT4_SB(sb)->s_qf_names[i]) {
2740                         int ret = ext4_quota_on_mount(sb, i);
2741
2742                         if (!ret)
2743                                 quota_update = 1;
2744                         else
2745                                 ext4_msg(sb, KERN_ERR,
2746                                         "Cannot turn on journaled "
2747                                         "quota: type %d: error %d", i, ret);
2748                 }
2749         }
2750 #endif
2751
2752         while (es->s_last_orphan) {
2753                 struct inode *inode;
2754
2755                 /*
2756                  * We may have encountered an error during cleanup; if
2757                  * so, skip the rest.
2758                  */
2759                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2760                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2761                         es->s_last_orphan = 0;
2762                         break;
2763                 }
2764
2765                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2766                 if (IS_ERR(inode)) {
2767                         es->s_last_orphan = 0;
2768                         break;
2769                 }
2770
2771                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2772                 dquot_initialize(inode);
2773                 if (inode->i_nlink) {
2774                         if (test_opt(sb, DEBUG))
2775                                 ext4_msg(sb, KERN_DEBUG,
2776                                         "%s: truncating inode %lu to %lld bytes",
2777                                         __func__, inode->i_ino, inode->i_size);
2778                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2779                                   inode->i_ino, inode->i_size);
2780                         inode_lock(inode);
2781                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2782                         ret = ext4_truncate(inode);
2783                         if (ret)
2784                                 ext4_std_error(inode->i_sb, ret);
2785                         inode_unlock(inode);
2786                         nr_truncates++;
2787                 } else {
2788                         if (test_opt(sb, DEBUG))
2789                                 ext4_msg(sb, KERN_DEBUG,
2790                                         "%s: deleting unreferenced inode %lu",
2791                                         __func__, inode->i_ino);
2792                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2793                                   inode->i_ino);
2794                         nr_orphans++;
2795                 }
2796                 iput(inode);  /* The delete magic happens here! */
2797         }
2798
2799 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2800
2801         if (nr_orphans)
2802                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2803                        PLURAL(nr_orphans));
2804         if (nr_truncates)
2805                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2806                        PLURAL(nr_truncates));
2807 #ifdef CONFIG_QUOTA
2808         /* Turn off quotas if they were enabled for orphan cleanup */
2809         if (quota_update) {
2810                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2811                         if (sb_dqopt(sb)->files[i])
2812                                 dquot_quota_off(sb, i);
2813                 }
2814         }
2815 #endif
2816         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2817 }
2818
2819 /*
2820  * Maximal extent format file size.
2821  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2822  * extent format containers, within a sector_t, and within i_blocks
2823  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2824  * so that won't be a limiting factor.
2825  *
2826  * However there is other limiting factor. We do store extents in the form
2827  * of starting block and length, hence the resulting length of the extent
2828  * covering maximum file size must fit into on-disk format containers as
2829  * well. Given that length is always by 1 unit bigger than max unit (because
2830  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2831  *
2832  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2833  */
2834 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2835 {
2836         loff_t res;
2837         loff_t upper_limit = MAX_LFS_FILESIZE;
2838
2839         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
2840
2841         if (!has_huge_files) {
2842                 upper_limit = (1LL << 32) - 1;
2843
2844                 /* total blocks in file system block size */
2845                 upper_limit >>= (blkbits - 9);
2846                 upper_limit <<= blkbits;
2847         }
2848
2849         /*
2850          * 32-bit extent-start container, ee_block. We lower the maxbytes
2851          * by one fs block, so ee_len can cover the extent of maximum file
2852          * size
2853          */
2854         res = (1LL << 32) - 1;
2855         res <<= blkbits;
2856
2857         /* Sanity check against vm- & vfs- imposed limits */
2858         if (res > upper_limit)
2859                 res = upper_limit;
2860
2861         return res;
2862 }
2863
2864 /*
2865  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2866  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2867  * We need to be 1 filesystem block less than the 2^48 sector limit.
2868  */
2869 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2870 {
2871         loff_t res = EXT4_NDIR_BLOCKS;
2872         int meta_blocks;
2873         loff_t upper_limit;
2874         /* This is calculated to be the largest file size for a dense, block
2875          * mapped file such that the file's total number of 512-byte sectors,
2876          * including data and all indirect blocks, does not exceed (2^48 - 1).
2877          *
2878          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2879          * number of 512-byte sectors of the file.
2880          */
2881
2882         if (!has_huge_files) {
2883                 /*
2884                  * !has_huge_files or implies that the inode i_block field
2885                  * represents total file blocks in 2^32 512-byte sectors ==
2886                  * size of vfs inode i_blocks * 8
2887                  */
2888                 upper_limit = (1LL << 32) - 1;
2889
2890                 /* total blocks in file system block size */
2891                 upper_limit >>= (bits - 9);
2892
2893         } else {
2894                 /*
2895                  * We use 48 bit ext4_inode i_blocks
2896                  * With EXT4_HUGE_FILE_FL set the i_blocks
2897                  * represent total number of blocks in
2898                  * file system block size
2899                  */
2900                 upper_limit = (1LL << 48) - 1;
2901
2902         }
2903
2904         /* indirect blocks */
2905         meta_blocks = 1;
2906         /* double indirect blocks */
2907         meta_blocks += 1 + (1LL << (bits-2));
2908         /* tripple indirect blocks */
2909         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2910
2911         upper_limit -= meta_blocks;
2912         upper_limit <<= bits;
2913
2914         res += 1LL << (bits-2);
2915         res += 1LL << (2*(bits-2));
2916         res += 1LL << (3*(bits-2));
2917         res <<= bits;
2918         if (res > upper_limit)
2919                 res = upper_limit;
2920
2921         if (res > MAX_LFS_FILESIZE)
2922                 res = MAX_LFS_FILESIZE;
2923
2924         return res;
2925 }
2926
2927 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2928                                    ext4_fsblk_t logical_sb_block, int nr)
2929 {
2930         struct ext4_sb_info *sbi = EXT4_SB(sb);
2931         ext4_group_t bg, first_meta_bg;
2932         int has_super = 0;
2933
2934         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2935
2936         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2937                 return logical_sb_block + nr + 1;
2938         bg = sbi->s_desc_per_block * nr;
2939         if (ext4_bg_has_super(sb, bg))
2940                 has_super = 1;
2941
2942         /*
2943          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2944          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2945          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2946          * compensate.
2947          */
2948         if (sb->s_blocksize == 1024 && nr == 0 &&
2949             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2950                 has_super++;
2951
2952         return (has_super + ext4_group_first_block_no(sb, bg));
2953 }
2954
2955 /**
2956  * ext4_get_stripe_size: Get the stripe size.
2957  * @sbi: In memory super block info
2958  *
2959  * If we have specified it via mount option, then
2960  * use the mount option value. If the value specified at mount time is
2961  * greater than the blocks per group use the super block value.
2962  * If the super block value is greater than blocks per group return 0.
2963  * Allocator needs it be less than blocks per group.
2964  *
2965  */
2966 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2967 {
2968         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2969         unsigned long stripe_width =
2970                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2971         int ret;
2972
2973         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2974                 ret = sbi->s_stripe;
2975         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2976                 ret = stripe_width;
2977         else if (stride && stride <= sbi->s_blocks_per_group)
2978                 ret = stride;
2979         else
2980                 ret = 0;
2981
2982         /*
2983          * If the stripe width is 1, this makes no sense and
2984          * we set it to 0 to turn off stripe handling code.
2985          */
2986         if (ret <= 1)
2987                 ret = 0;
2988
2989         return ret;
2990 }
2991
2992 /*
2993  * Check whether this filesystem can be mounted based on
2994  * the features present and the RDONLY/RDWR mount requested.
2995  * Returns 1 if this filesystem can be mounted as requested,
2996  * 0 if it cannot be.
2997  */
2998 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2999 {
3000         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3001                 ext4_msg(sb, KERN_ERR,
3002                         "Couldn't mount because of "
3003                         "unsupported optional features (%x)",
3004                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3005                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3006                 return 0;
3007         }
3008
3009 #ifndef CONFIG_UNICODE
3010         if (ext4_has_feature_casefold(sb)) {
3011                 ext4_msg(sb, KERN_ERR,
3012                          "Filesystem with casefold feature cannot be "
3013                          "mounted without CONFIG_UNICODE");
3014                 return 0;
3015         }
3016 #endif
3017
3018         if (readonly)
3019                 return 1;
3020
3021         if (ext4_has_feature_readonly(sb)) {
3022                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3023                 sb->s_flags |= SB_RDONLY;
3024                 return 1;
3025         }
3026
3027         /* Check that feature set is OK for a read-write mount */
3028         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3029                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3030                          "unsupported optional features (%x)",
3031                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3032                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3033                 return 0;
3034         }
3035         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3036                 ext4_msg(sb, KERN_ERR,
3037                          "Can't support bigalloc feature without "
3038                          "extents feature\n");
3039                 return 0;
3040         }
3041
3042 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3043         if (!readonly && (ext4_has_feature_quota(sb) ||
3044                           ext4_has_feature_project(sb))) {
3045                 ext4_msg(sb, KERN_ERR,
3046                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3047                 return 0;
3048         }
3049 #endif  /* CONFIG_QUOTA */
3050         return 1;
3051 }
3052
3053 /*
3054  * This function is called once a day if we have errors logged
3055  * on the file system
3056  */
3057 static void print_daily_error_info(struct timer_list *t)
3058 {
3059         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3060         struct super_block *sb = sbi->s_sb;
3061         struct ext4_super_block *es = sbi->s_es;
3062
3063         if (es->s_error_count)
3064                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3065                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3066                          le32_to_cpu(es->s_error_count));
3067         if (es->s_first_error_time) {
3068                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3069                        sb->s_id,
3070                        ext4_get_tstamp(es, s_first_error_time),
3071                        (int) sizeof(es->s_first_error_func),
3072                        es->s_first_error_func,
3073                        le32_to_cpu(es->s_first_error_line));
3074                 if (es->s_first_error_ino)
3075                         printk(KERN_CONT ": inode %u",
3076                                le32_to_cpu(es->s_first_error_ino));
3077                 if (es->s_first_error_block)
3078                         printk(KERN_CONT ": block %llu", (unsigned long long)
3079                                le64_to_cpu(es->s_first_error_block));
3080                 printk(KERN_CONT "\n");
3081         }
3082         if (es->s_last_error_time) {
3083                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3084                        sb->s_id,
3085                        ext4_get_tstamp(es, s_last_error_time),
3086                        (int) sizeof(es->s_last_error_func),
3087                        es->s_last_error_func,
3088                        le32_to_cpu(es->s_last_error_line));
3089                 if (es->s_last_error_ino)
3090                         printk(KERN_CONT ": inode %u",
3091                                le32_to_cpu(es->s_last_error_ino));
3092                 if (es->s_last_error_block)
3093                         printk(KERN_CONT ": block %llu", (unsigned long long)
3094                                le64_to_cpu(es->s_last_error_block));
3095                 printk(KERN_CONT "\n");
3096         }
3097         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3098 }
3099
3100 /* Find next suitable group and run ext4_init_inode_table */
3101 static int ext4_run_li_request(struct ext4_li_request *elr)
3102 {
3103         struct ext4_group_desc *gdp = NULL;
3104         ext4_group_t group, ngroups;
3105         struct super_block *sb;
3106         unsigned long timeout = 0;
3107         int ret = 0;
3108
3109         sb = elr->lr_super;
3110         ngroups = EXT4_SB(sb)->s_groups_count;
3111
3112         for (group = elr->lr_next_group; group < ngroups; group++) {
3113                 gdp = ext4_get_group_desc(sb, group, NULL);
3114                 if (!gdp) {
3115                         ret = 1;
3116                         break;
3117                 }
3118
3119                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3120                         break;
3121         }
3122
3123         if (group >= ngroups)
3124                 ret = 1;
3125
3126         if (!ret) {
3127                 timeout = jiffies;
3128                 ret = ext4_init_inode_table(sb, group,
3129                                             elr->lr_timeout ? 0 : 1);
3130                 if (elr->lr_timeout == 0) {
3131                         timeout = (jiffies - timeout) *
3132                                   elr->lr_sbi->s_li_wait_mult;
3133                         elr->lr_timeout = timeout;
3134                 }
3135                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3136                 elr->lr_next_group = group + 1;
3137         }
3138         return ret;
3139 }
3140
3141 /*
3142  * Remove lr_request from the list_request and free the
3143  * request structure. Should be called with li_list_mtx held
3144  */
3145 static void ext4_remove_li_request(struct ext4_li_request *elr)
3146 {
3147         struct ext4_sb_info *sbi;
3148
3149         if (!elr)
3150                 return;
3151
3152         sbi = elr->lr_sbi;
3153
3154         list_del(&elr->lr_request);
3155         sbi->s_li_request = NULL;
3156         kfree(elr);
3157 }
3158
3159 static void ext4_unregister_li_request(struct super_block *sb)
3160 {
3161         mutex_lock(&ext4_li_mtx);
3162         if (!ext4_li_info) {
3163                 mutex_unlock(&ext4_li_mtx);
3164                 return;
3165         }
3166
3167         mutex_lock(&ext4_li_info->li_list_mtx);
3168         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3169         mutex_unlock(&ext4_li_info->li_list_mtx);
3170         mutex_unlock(&ext4_li_mtx);
3171 }
3172
3173 static struct task_struct *ext4_lazyinit_task;
3174
3175 /*
3176  * This is the function where ext4lazyinit thread lives. It walks
3177  * through the request list searching for next scheduled filesystem.
3178  * When such a fs is found, run the lazy initialization request
3179  * (ext4_rn_li_request) and keep track of the time spend in this
3180  * function. Based on that time we compute next schedule time of
3181  * the request. When walking through the list is complete, compute
3182  * next waking time and put itself into sleep.
3183  */
3184 static int ext4_lazyinit_thread(void *arg)
3185 {
3186         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3187         struct list_head *pos, *n;
3188         struct ext4_li_request *elr;
3189         unsigned long next_wakeup, cur;
3190
3191         BUG_ON(NULL == eli);
3192
3193 cont_thread:
3194         while (true) {
3195                 next_wakeup = MAX_JIFFY_OFFSET;
3196
3197                 mutex_lock(&eli->li_list_mtx);
3198                 if (list_empty(&eli->li_request_list)) {
3199                         mutex_unlock(&eli->li_list_mtx);
3200                         goto exit_thread;
3201                 }
3202                 list_for_each_safe(pos, n, &eli->li_request_list) {
3203                         int err = 0;
3204                         int progress = 0;
3205                         elr = list_entry(pos, struct ext4_li_request,
3206                                          lr_request);
3207
3208                         if (time_before(jiffies, elr->lr_next_sched)) {
3209                                 if (time_before(elr->lr_next_sched, next_wakeup))
3210                                         next_wakeup = elr->lr_next_sched;
3211                                 continue;
3212                         }
3213                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3214                                 if (sb_start_write_trylock(elr->lr_super)) {
3215                                         progress = 1;
3216                                         /*
3217                                          * We hold sb->s_umount, sb can not
3218                                          * be removed from the list, it is
3219                                          * now safe to drop li_list_mtx
3220                                          */
3221                                         mutex_unlock(&eli->li_list_mtx);
3222                                         err = ext4_run_li_request(elr);
3223                                         sb_end_write(elr->lr_super);
3224                                         mutex_lock(&eli->li_list_mtx);
3225                                         n = pos->next;
3226                                 }
3227                                 up_read((&elr->lr_super->s_umount));
3228                         }
3229                         /* error, remove the lazy_init job */
3230                         if (err) {
3231                                 ext4_remove_li_request(elr);
3232                                 continue;
3233                         }
3234                         if (!progress) {
3235                                 elr->lr_next_sched = jiffies +
3236                                         (prandom_u32()
3237                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3238                         }
3239                         if (time_before(elr->lr_next_sched, next_wakeup))
3240                                 next_wakeup = elr->lr_next_sched;
3241                 }
3242                 mutex_unlock(&eli->li_list_mtx);
3243
3244                 try_to_freeze();
3245
3246                 cur = jiffies;
3247                 if ((time_after_eq(cur, next_wakeup)) ||
3248                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3249                         cond_resched();
3250                         continue;
3251                 }
3252
3253                 schedule_timeout_interruptible(next_wakeup - cur);
3254
3255                 if (kthread_should_stop()) {
3256                         ext4_clear_request_list();
3257                         goto exit_thread;
3258                 }
3259         }
3260
3261 exit_thread:
3262         /*
3263          * It looks like the request list is empty, but we need
3264          * to check it under the li_list_mtx lock, to prevent any
3265          * additions into it, and of course we should lock ext4_li_mtx
3266          * to atomically free the list and ext4_li_info, because at
3267          * this point another ext4 filesystem could be registering
3268          * new one.
3269          */
3270         mutex_lock(&ext4_li_mtx);
3271         mutex_lock(&eli->li_list_mtx);
3272         if (!list_empty(&eli->li_request_list)) {
3273                 mutex_unlock(&eli->li_list_mtx);
3274                 mutex_unlock(&ext4_li_mtx);
3275                 goto cont_thread;
3276         }
3277         mutex_unlock(&eli->li_list_mtx);
3278         kfree(ext4_li_info);
3279         ext4_li_info = NULL;
3280         mutex_unlock(&ext4_li_mtx);
3281
3282         return 0;
3283 }
3284
3285 static void ext4_clear_request_list(void)
3286 {
3287         struct list_head *pos, *n;
3288         struct ext4_li_request *elr;
3289
3290         mutex_lock(&ext4_li_info->li_list_mtx);
3291         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3292                 elr = list_entry(pos, struct ext4_li_request,
3293                                  lr_request);
3294                 ext4_remove_li_request(elr);
3295         }
3296         mutex_unlock(&ext4_li_info->li_list_mtx);
3297 }
3298
3299 static int ext4_run_lazyinit_thread(void)
3300 {
3301         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3302                                          ext4_li_info, "ext4lazyinit");
3303         if (IS_ERR(ext4_lazyinit_task)) {
3304                 int err = PTR_ERR(ext4_lazyinit_task);
3305                 ext4_clear_request_list();
3306                 kfree(ext4_li_info);
3307                 ext4_li_info = NULL;
3308                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3309                                  "initialization thread\n",
3310                                  err);
3311                 return err;
3312         }
3313         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3314         return 0;
3315 }
3316
3317 /*
3318  * Check whether it make sense to run itable init. thread or not.
3319  * If there is at least one uninitialized inode table, return
3320  * corresponding group number, else the loop goes through all
3321  * groups and return total number of groups.
3322  */
3323 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3324 {
3325         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3326         struct ext4_group_desc *gdp = NULL;
3327
3328         if (!ext4_has_group_desc_csum(sb))
3329                 return ngroups;
3330
3331         for (group = 0; group < ngroups; group++) {
3332                 gdp = ext4_get_group_desc(sb, group, NULL);
3333                 if (!gdp)
3334                         continue;
3335
3336                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3337                         break;
3338         }
3339
3340         return group;
3341 }
3342
3343 static int ext4_li_info_new(void)
3344 {
3345         struct ext4_lazy_init *eli = NULL;
3346
3347         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3348         if (!eli)
3349                 return -ENOMEM;
3350
3351         INIT_LIST_HEAD(&eli->li_request_list);
3352         mutex_init(&eli->li_list_mtx);
3353
3354         eli->li_state |= EXT4_LAZYINIT_QUIT;
3355
3356         ext4_li_info = eli;
3357
3358         return 0;
3359 }
3360
3361 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3362                                             ext4_group_t start)
3363 {
3364         struct ext4_sb_info *sbi = EXT4_SB(sb);
3365         struct ext4_li_request *elr;
3366
3367         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3368         if (!elr)
3369                 return NULL;
3370
3371         elr->lr_super = sb;
3372         elr->lr_sbi = sbi;
3373         elr->lr_next_group = start;
3374
3375         /*
3376          * Randomize first schedule time of the request to
3377          * spread the inode table initialization requests
3378          * better.
3379          */
3380         elr->lr_next_sched = jiffies + (prandom_u32() %
3381                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3382         return elr;
3383 }
3384
3385 int ext4_register_li_request(struct super_block *sb,
3386                              ext4_group_t first_not_zeroed)
3387 {
3388         struct ext4_sb_info *sbi = EXT4_SB(sb);
3389         struct ext4_li_request *elr = NULL;
3390         ext4_group_t ngroups = sbi->s_groups_count;
3391         int ret = 0;
3392
3393         mutex_lock(&ext4_li_mtx);
3394         if (sbi->s_li_request != NULL) {
3395                 /*
3396                  * Reset timeout so it can be computed again, because
3397                  * s_li_wait_mult might have changed.
3398                  */
3399                 sbi->s_li_request->lr_timeout = 0;
3400                 goto out;
3401         }
3402
3403         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3404             !test_opt(sb, INIT_INODE_TABLE))
3405                 goto out;
3406
3407         elr = ext4_li_request_new(sb, first_not_zeroed);
3408         if (!elr) {
3409                 ret = -ENOMEM;
3410                 goto out;
3411         }
3412
3413         if (NULL == ext4_li_info) {
3414                 ret = ext4_li_info_new();
3415                 if (ret)
3416                         goto out;
3417         }
3418
3419         mutex_lock(&ext4_li_info->li_list_mtx);
3420         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3421         mutex_unlock(&ext4_li_info->li_list_mtx);
3422
3423         sbi->s_li_request = elr;
3424         /*
3425          * set elr to NULL here since it has been inserted to
3426          * the request_list and the removal and free of it is
3427          * handled by ext4_clear_request_list from now on.
3428          */
3429         elr = NULL;
3430
3431         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3432                 ret = ext4_run_lazyinit_thread();
3433                 if (ret)
3434                         goto out;
3435         }
3436 out:
3437         mutex_unlock(&ext4_li_mtx);
3438         if (ret)
3439                 kfree(elr);
3440         return ret;
3441 }
3442
3443 /*
3444  * We do not need to lock anything since this is called on
3445  * module unload.
3446  */
3447 static void ext4_destroy_lazyinit_thread(void)
3448 {
3449         /*
3450          * If thread exited earlier
3451          * there's nothing to be done.
3452          */
3453         if (!ext4_li_info || !ext4_lazyinit_task)
3454                 return;
3455
3456         kthread_stop(ext4_lazyinit_task);
3457 }
3458
3459 static int set_journal_csum_feature_set(struct super_block *sb)
3460 {
3461         int ret = 1;
3462         int compat, incompat;
3463         struct ext4_sb_info *sbi = EXT4_SB(sb);
3464
3465         if (ext4_has_metadata_csum(sb)) {
3466                 /* journal checksum v3 */
3467                 compat = 0;
3468                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3469         } else {
3470                 /* journal checksum v1 */
3471                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3472                 incompat = 0;
3473         }
3474
3475         jbd2_journal_clear_features(sbi->s_journal,
3476                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3477                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3478                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3479         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3480                 ret = jbd2_journal_set_features(sbi->s_journal,
3481                                 compat, 0,
3482                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3483                                 incompat);
3484         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3485                 ret = jbd2_journal_set_features(sbi->s_journal,
3486                                 compat, 0,
3487                                 incompat);
3488                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3489                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3490         } else {
3491                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3492                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3493         }
3494
3495         return ret;
3496 }
3497
3498 /*
3499  * Note: calculating the overhead so we can be compatible with
3500  * historical BSD practice is quite difficult in the face of
3501  * clusters/bigalloc.  This is because multiple metadata blocks from
3502  * different block group can end up in the same allocation cluster.
3503  * Calculating the exact overhead in the face of clustered allocation
3504  * requires either O(all block bitmaps) in memory or O(number of block
3505  * groups**2) in time.  We will still calculate the superblock for
3506  * older file systems --- and if we come across with a bigalloc file
3507  * system with zero in s_overhead_clusters the estimate will be close to
3508  * correct especially for very large cluster sizes --- but for newer
3509  * file systems, it's better to calculate this figure once at mkfs
3510  * time, and store it in the superblock.  If the superblock value is
3511  * present (even for non-bigalloc file systems), we will use it.
3512  */
3513 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3514                           char *buf)
3515 {
3516         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3517         struct ext4_group_desc  *gdp;
3518         ext4_fsblk_t            first_block, last_block, b;
3519         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3520         int                     s, j, count = 0;
3521
3522         if (!ext4_has_feature_bigalloc(sb))
3523                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3524                         sbi->s_itb_per_group + 2);
3525
3526         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3527                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3528         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3529         for (i = 0; i < ngroups; i++) {
3530                 gdp = ext4_get_group_desc(sb, i, NULL);
3531                 b = ext4_block_bitmap(sb, gdp);
3532                 if (b >= first_block && b <= last_block) {
3533                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3534                         count++;
3535                 }
3536                 b = ext4_inode_bitmap(sb, gdp);
3537                 if (b >= first_block && b <= last_block) {
3538                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3539                         count++;
3540                 }
3541                 b = ext4_inode_table(sb, gdp);
3542                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3543                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3544                                 int c = EXT4_B2C(sbi, b - first_block);
3545                                 ext4_set_bit(c, buf);
3546                                 count++;
3547                         }
3548                 if (i != grp)
3549                         continue;
3550                 s = 0;
3551                 if (ext4_bg_has_super(sb, grp)) {
3552                         ext4_set_bit(s++, buf);
3553                         count++;
3554                 }
3555                 j = ext4_bg_num_gdb(sb, grp);
3556                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3557                         ext4_error(sb, "Invalid number of block group "
3558                                    "descriptor blocks: %d", j);
3559                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3560                 }
3561                 count += j;
3562                 for (; j > 0; j--)
3563                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3564         }
3565         if (!count)
3566                 return 0;
3567         return EXT4_CLUSTERS_PER_GROUP(sb) -
3568                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3569 }
3570
3571 /*
3572  * Compute the overhead and stash it in sbi->s_overhead
3573  */
3574 int ext4_calculate_overhead(struct super_block *sb)
3575 {
3576         struct ext4_sb_info *sbi = EXT4_SB(sb);
3577         struct ext4_super_block *es = sbi->s_es;
3578         struct inode *j_inode;
3579         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3580         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3581         ext4_fsblk_t overhead = 0;
3582         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3583
3584         if (!buf)
3585                 return -ENOMEM;
3586
3587         /*
3588          * Compute the overhead (FS structures).  This is constant
3589          * for a given filesystem unless the number of block groups
3590          * changes so we cache the previous value until it does.
3591          */
3592
3593         /*
3594          * All of the blocks before first_data_block are overhead
3595          */
3596         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3597
3598         /*
3599          * Add the overhead found in each block group
3600          */
3601         for (i = 0; i < ngroups; i++) {
3602                 int blks;
3603
3604                 blks = count_overhead(sb, i, buf);
3605                 overhead += blks;
3606                 if (blks)
3607                         memset(buf, 0, PAGE_SIZE);
3608                 cond_resched();
3609         }
3610
3611         /*
3612          * Add the internal journal blocks whether the journal has been
3613          * loaded or not
3614          */
3615         if (sbi->s_journal && !sbi->journal_bdev)
3616                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3617         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3618                 /* j_inum for internal journal is non-zero */
3619                 j_inode = ext4_get_journal_inode(sb, j_inum);
3620                 if (j_inode) {
3621                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3622                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3623                         iput(j_inode);
3624                 } else {
3625                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3626                 }
3627         }
3628         sbi->s_overhead = overhead;
3629         smp_wmb();
3630         free_page((unsigned long) buf);
3631         return 0;
3632 }
3633
3634 static void ext4_set_resv_clusters(struct super_block *sb)
3635 {
3636         ext4_fsblk_t resv_clusters;
3637         struct ext4_sb_info *sbi = EXT4_SB(sb);
3638
3639         /*
3640          * There's no need to reserve anything when we aren't using extents.
3641          * The space estimates are exact, there are no unwritten extents,
3642          * hole punching doesn't need new metadata... This is needed especially
3643          * to keep ext2/3 backward compatibility.
3644          */
3645         if (!ext4_has_feature_extents(sb))
3646                 return;
3647         /*
3648          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3649          * This should cover the situations where we can not afford to run
3650          * out of space like for example punch hole, or converting
3651          * unwritten extents in delalloc path. In most cases such
3652          * allocation would require 1, or 2 blocks, higher numbers are
3653          * very rare.
3654          */
3655         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3656                          sbi->s_cluster_bits);
3657
3658         do_div(resv_clusters, 50);
3659         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3660
3661         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3662 }
3663
3664 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3665 {
3666         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3667         char *orig_data = kstrdup(data, GFP_KERNEL);
3668         struct buffer_head *bh, **group_desc;
3669         struct ext4_super_block *es = NULL;
3670         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3671         struct flex_groups **flex_groups;
3672         ext4_fsblk_t block;
3673         ext4_fsblk_t sb_block = get_sb_block(&data);
3674         ext4_fsblk_t logical_sb_block;
3675         unsigned long offset = 0;
3676         unsigned long journal_devnum = 0;
3677         unsigned long def_mount_opts;
3678         struct inode *root;
3679         const char *descr;
3680         int ret = -ENOMEM;
3681         int blocksize, clustersize;
3682         unsigned int db_count;
3683         unsigned int i;
3684         int needs_recovery, has_huge_files, has_bigalloc;
3685         __u64 blocks_count;
3686         int err = 0;
3687         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3688         ext4_group_t first_not_zeroed;
3689
3690         if ((data && !orig_data) || !sbi)
3691                 goto out_free_base;
3692
3693         sbi->s_daxdev = dax_dev;
3694         sbi->s_blockgroup_lock =
3695                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3696         if (!sbi->s_blockgroup_lock)
3697                 goto out_free_base;
3698
3699         sb->s_fs_info = sbi;
3700         sbi->s_sb = sb;
3701         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3702         sbi->s_sb_block = sb_block;
3703         if (sb->s_bdev->bd_part)
3704                 sbi->s_sectors_written_start =
3705                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3706
3707         /* Cleanup superblock name */
3708         strreplace(sb->s_id, '/', '!');
3709
3710         /* -EINVAL is default */
3711         ret = -EINVAL;
3712         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3713         if (!blocksize) {
3714                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3715                 goto out_fail;
3716         }
3717
3718         /*
3719          * The ext4 superblock will not be buffer aligned for other than 1kB
3720          * block sizes.  We need to calculate the offset from buffer start.
3721          */
3722         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3723                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3724                 offset = do_div(logical_sb_block, blocksize);
3725         } else {
3726                 logical_sb_block = sb_block;
3727         }
3728
3729         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3730                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3731                 goto out_fail;
3732         }
3733         /*
3734          * Note: s_es must be initialized as soon as possible because
3735          *       some ext4 macro-instructions depend on its value
3736          */
3737         es = (struct ext4_super_block *) (bh->b_data + offset);
3738         sbi->s_es = es;
3739         sb->s_magic = le16_to_cpu(es->s_magic);
3740         if (sb->s_magic != EXT4_SUPER_MAGIC)
3741                 goto cantfind_ext4;
3742         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3743
3744         /* Warn if metadata_csum and gdt_csum are both set. */
3745         if (ext4_has_feature_metadata_csum(sb) &&
3746             ext4_has_feature_gdt_csum(sb))
3747                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3748                              "redundant flags; please run fsck.");
3749
3750         /* Check for a known checksum algorithm */
3751         if (!ext4_verify_csum_type(sb, es)) {
3752                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3753                          "unknown checksum algorithm.");
3754                 silent = 1;
3755                 goto cantfind_ext4;
3756         }
3757
3758         /* Load the checksum driver */
3759         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3760         if (IS_ERR(sbi->s_chksum_driver)) {
3761                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3762                 ret = PTR_ERR(sbi->s_chksum_driver);
3763                 sbi->s_chksum_driver = NULL;
3764                 goto failed_mount;
3765         }
3766
3767         /* Check superblock checksum */
3768         if (!ext4_superblock_csum_verify(sb, es)) {
3769                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3770                          "invalid superblock checksum.  Run e2fsck?");
3771                 silent = 1;
3772                 ret = -EFSBADCRC;
3773                 goto cantfind_ext4;
3774         }
3775
3776         /* Precompute checksum seed for all metadata */
3777         if (ext4_has_feature_csum_seed(sb))
3778                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3779         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3780                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3781                                                sizeof(es->s_uuid));
3782
3783         /* Set defaults before we parse the mount options */
3784         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3785         set_opt(sb, INIT_INODE_TABLE);
3786         if (def_mount_opts & EXT4_DEFM_DEBUG)
3787                 set_opt(sb, DEBUG);
3788         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3789                 set_opt(sb, GRPID);
3790         if (def_mount_opts & EXT4_DEFM_UID16)
3791                 set_opt(sb, NO_UID32);
3792         /* xattr user namespace & acls are now defaulted on */
3793         set_opt(sb, XATTR_USER);
3794 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3795         set_opt(sb, POSIX_ACL);
3796 #endif
3797         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3798         if (ext4_has_metadata_csum(sb))
3799                 set_opt(sb, JOURNAL_CHECKSUM);
3800
3801         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3802                 set_opt(sb, JOURNAL_DATA);
3803         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3804                 set_opt(sb, ORDERED_DATA);
3805         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3806                 set_opt(sb, WRITEBACK_DATA);
3807
3808         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3809                 set_opt(sb, ERRORS_PANIC);
3810         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3811                 set_opt(sb, ERRORS_CONT);
3812         else
3813                 set_opt(sb, ERRORS_RO);
3814         /* block_validity enabled by default; disable with noblock_validity */
3815         set_opt(sb, BLOCK_VALIDITY);
3816         if (def_mount_opts & EXT4_DEFM_DISCARD)
3817                 set_opt(sb, DISCARD);
3818
3819         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3820         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3821         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3822         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3823         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3824
3825         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3826                 set_opt(sb, BARRIER);
3827
3828         /*
3829          * enable delayed allocation by default
3830          * Use -o nodelalloc to turn it off
3831          */
3832         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3833             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3834                 set_opt(sb, DELALLOC);
3835
3836         /*
3837          * set default s_li_wait_mult for lazyinit, for the case there is
3838          * no mount option specified.
3839          */
3840         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3841
3842         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3843
3844         if (blocksize == PAGE_SIZE)
3845                 set_opt(sb, DIOREAD_NOLOCK);
3846
3847         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3848             blocksize > EXT4_MAX_BLOCK_SIZE) {
3849                 ext4_msg(sb, KERN_ERR,
3850                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3851                          blocksize, le32_to_cpu(es->s_log_block_size));
3852                 goto failed_mount;
3853         }
3854
3855         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3856                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3857                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3858         } else {
3859                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3860                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3861                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3862                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3863                                  sbi->s_first_ino);
3864                         goto failed_mount;
3865                 }
3866                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3867                     (!is_power_of_2(sbi->s_inode_size)) ||
3868                     (sbi->s_inode_size > blocksize)) {
3869                         ext4_msg(sb, KERN_ERR,
3870                                "unsupported inode size: %d",
3871                                sbi->s_inode_size);
3872                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
3873                         goto failed_mount;
3874                 }
3875                 /*
3876                  * i_atime_extra is the last extra field available for
3877                  * [acm]times in struct ext4_inode. Checking for that
3878                  * field should suffice to ensure we have extra space
3879                  * for all three.
3880                  */
3881                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
3882                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
3883                         sb->s_time_gran = 1;
3884                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
3885                 } else {
3886                         sb->s_time_gran = NSEC_PER_SEC;
3887                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
3888                 }
3889                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
3890         }
3891         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3892                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3893                         EXT4_GOOD_OLD_INODE_SIZE;
3894                 if (ext4_has_feature_extra_isize(sb)) {
3895                         unsigned v, max = (sbi->s_inode_size -
3896                                            EXT4_GOOD_OLD_INODE_SIZE);
3897
3898                         v = le16_to_cpu(es->s_want_extra_isize);
3899                         if (v > max) {
3900                                 ext4_msg(sb, KERN_ERR,
3901                                          "bad s_want_extra_isize: %d", v);
3902                                 goto failed_mount;
3903                         }
3904                         if (sbi->s_want_extra_isize < v)
3905                                 sbi->s_want_extra_isize = v;
3906
3907                         v = le16_to_cpu(es->s_min_extra_isize);
3908                         if (v > max) {
3909                                 ext4_msg(sb, KERN_ERR,
3910                                          "bad s_min_extra_isize: %d", v);
3911                                 goto failed_mount;
3912                         }
3913                         if (sbi->s_want_extra_isize < v)
3914                                 sbi->s_want_extra_isize = v;
3915                 }
3916         }
3917
3918         if (sbi->s_es->s_mount_opts[0]) {
3919                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3920                                               sizeof(sbi->s_es->s_mount_opts),
3921                                               GFP_KERNEL);
3922                 if (!s_mount_opts)
3923                         goto failed_mount;
3924                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3925                                    &journal_ioprio, 0)) {
3926                         ext4_msg(sb, KERN_WARNING,
3927                                  "failed to parse options in superblock: %s",
3928                                  s_mount_opts);
3929                 }
3930                 kfree(s_mount_opts);
3931         }
3932         sbi->s_def_mount_opt = sbi->s_mount_opt;
3933         if (!parse_options((char *) data, sb, &journal_devnum,
3934                            &journal_ioprio, 0))
3935                 goto failed_mount;
3936
3937 #ifdef CONFIG_UNICODE
3938         if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
3939                 const struct ext4_sb_encodings *encoding_info;
3940                 struct unicode_map *encoding;
3941                 __u16 encoding_flags;
3942
3943                 if (ext4_has_feature_encrypt(sb)) {
3944                         ext4_msg(sb, KERN_ERR,
3945                                  "Can't mount with encoding and encryption");
3946                         goto failed_mount;
3947                 }
3948
3949                 if (ext4_sb_read_encoding(es, &encoding_info,
3950                                           &encoding_flags)) {
3951                         ext4_msg(sb, KERN_ERR,
3952                                  "Encoding requested by superblock is unknown");
3953                         goto failed_mount;
3954                 }
3955
3956                 encoding = utf8_load(encoding_info->version);
3957                 if (IS_ERR(encoding)) {
3958                         ext4_msg(sb, KERN_ERR,
3959                                  "can't mount with superblock charset: %s-%s "
3960                                  "not supported by the kernel. flags: 0x%x.",
3961                                  encoding_info->name, encoding_info->version,
3962                                  encoding_flags);
3963                         goto failed_mount;
3964                 }
3965                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
3966                          "%s-%s with flags 0x%hx", encoding_info->name,
3967                          encoding_info->version?:"\b", encoding_flags);
3968
3969                 sbi->s_encoding = encoding;
3970                 sbi->s_encoding_flags = encoding_flags;
3971         }
3972 #endif
3973
3974         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3975                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, and O_DIRECT support!\n");
3976                 clear_opt(sb, DIOREAD_NOLOCK);
3977                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3978                         ext4_msg(sb, KERN_ERR, "can't mount with "
3979                                  "both data=journal and delalloc");
3980                         goto failed_mount;
3981                 }
3982                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3983                         ext4_msg(sb, KERN_ERR, "can't mount with "
3984                                  "both data=journal and dioread_nolock");
3985                         goto failed_mount;
3986                 }
3987                 if (test_opt(sb, DAX)) {
3988                         ext4_msg(sb, KERN_ERR, "can't mount with "
3989                                  "both data=journal and dax");
3990                         goto failed_mount;
3991                 }
3992                 if (ext4_has_feature_encrypt(sb)) {
3993                         ext4_msg(sb, KERN_WARNING,
3994                                  "encrypted files will use data=ordered "
3995                                  "instead of data journaling mode");
3996                 }
3997                 if (test_opt(sb, DELALLOC))
3998                         clear_opt(sb, DELALLOC);
3999         } else {
4000                 sb->s_iflags |= SB_I_CGROUPWB;
4001         }
4002
4003         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4004                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4005
4006         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4007             (ext4_has_compat_features(sb) ||
4008              ext4_has_ro_compat_features(sb) ||
4009              ext4_has_incompat_features(sb)))
4010                 ext4_msg(sb, KERN_WARNING,
4011                        "feature flags set on rev 0 fs, "
4012                        "running e2fsck is recommended");
4013
4014         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4015                 set_opt2(sb, HURD_COMPAT);
4016                 if (ext4_has_feature_64bit(sb)) {
4017                         ext4_msg(sb, KERN_ERR,
4018                                  "The Hurd can't support 64-bit file systems");
4019                         goto failed_mount;
4020                 }
4021
4022                 /*
4023                  * ea_inode feature uses l_i_version field which is not
4024                  * available in HURD_COMPAT mode.
4025                  */
4026                 if (ext4_has_feature_ea_inode(sb)) {
4027                         ext4_msg(sb, KERN_ERR,
4028                                  "ea_inode feature is not supported for Hurd");
4029                         goto failed_mount;
4030                 }
4031         }
4032
4033         if (IS_EXT2_SB(sb)) {
4034                 if (ext2_feature_set_ok(sb))
4035                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4036                                  "using the ext4 subsystem");
4037                 else {
4038                         /*
4039                          * If we're probing be silent, if this looks like
4040                          * it's actually an ext[34] filesystem.
4041                          */
4042                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4043                                 goto failed_mount;
4044                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4045                                  "to feature incompatibilities");
4046                         goto failed_mount;
4047                 }
4048         }
4049
4050         if (IS_EXT3_SB(sb)) {
4051                 if (ext3_feature_set_ok(sb))
4052                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4053                                  "using the ext4 subsystem");
4054                 else {
4055                         /*
4056                          * If we're probing be silent, if this looks like
4057                          * it's actually an ext4 filesystem.
4058                          */
4059                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4060                                 goto failed_mount;
4061                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4062                                  "to feature incompatibilities");
4063                         goto failed_mount;
4064                 }
4065         }
4066
4067         /*
4068          * Check feature flags regardless of the revision level, since we
4069          * previously didn't change the revision level when setting the flags,
4070          * so there is a chance incompat flags are set on a rev 0 filesystem.
4071          */
4072         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4073                 goto failed_mount;
4074
4075         if (le32_to_cpu(es->s_log_block_size) >
4076             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4077                 ext4_msg(sb, KERN_ERR,
4078                          "Invalid log block size: %u",
4079                          le32_to_cpu(es->s_log_block_size));
4080                 goto failed_mount;
4081         }
4082         if (le32_to_cpu(es->s_log_cluster_size) >
4083             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4084                 ext4_msg(sb, KERN_ERR,
4085                          "Invalid log cluster size: %u",
4086                          le32_to_cpu(es->s_log_cluster_size));
4087                 goto failed_mount;
4088         }
4089
4090         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4091                 ext4_msg(sb, KERN_ERR,
4092                          "Number of reserved GDT blocks insanely large: %d",
4093                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4094                 goto failed_mount;
4095         }
4096
4097         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
4098                 if (ext4_has_feature_inline_data(sb)) {
4099                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4100                                         " that may contain inline data");
4101                         goto failed_mount;
4102                 }
4103                 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
4104                         ext4_msg(sb, KERN_ERR,
4105                                 "DAX unsupported by block device.");
4106                         goto failed_mount;
4107                 }
4108         }
4109
4110         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4111                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4112                          es->s_encryption_level);
4113                 goto failed_mount;
4114         }
4115
4116         if (sb->s_blocksize != blocksize) {
4117                 /* Validate the filesystem blocksize */
4118                 if (!sb_set_blocksize(sb, blocksize)) {
4119                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4120                                         blocksize);
4121                         goto failed_mount;
4122                 }
4123
4124                 brelse(bh);
4125                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4126                 offset = do_div(logical_sb_block, blocksize);
4127                 bh = sb_bread_unmovable(sb, logical_sb_block);
4128                 if (!bh) {
4129                         ext4_msg(sb, KERN_ERR,
4130                                "Can't read superblock on 2nd try");
4131                         goto failed_mount;
4132                 }
4133                 es = (struct ext4_super_block *)(bh->b_data + offset);
4134                 sbi->s_es = es;
4135                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4136                         ext4_msg(sb, KERN_ERR,
4137                                "Magic mismatch, very weird!");
4138                         goto failed_mount;
4139                 }
4140         }
4141
4142         has_huge_files = ext4_has_feature_huge_file(sb);
4143         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4144                                                       has_huge_files);
4145         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4146
4147         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4148         if (ext4_has_feature_64bit(sb)) {
4149                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4150                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4151                     !is_power_of_2(sbi->s_desc_size)) {
4152                         ext4_msg(sb, KERN_ERR,
4153                                "unsupported descriptor size %lu",
4154                                sbi->s_desc_size);
4155                         goto failed_mount;
4156                 }
4157         } else
4158                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4159
4160         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4161         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4162
4163         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4164         if (sbi->s_inodes_per_block == 0)
4165                 goto cantfind_ext4;
4166         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4167             sbi->s_inodes_per_group > blocksize * 8) {
4168                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4169                          sbi->s_inodes_per_group);
4170                 goto failed_mount;
4171         }
4172         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4173                                         sbi->s_inodes_per_block;
4174         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4175         sbi->s_sbh = bh;
4176         sbi->s_mount_state = le16_to_cpu(es->s_state);
4177         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4178         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4179
4180         for (i = 0; i < 4; i++)
4181                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4182         sbi->s_def_hash_version = es->s_def_hash_version;
4183         if (ext4_has_feature_dir_index(sb)) {
4184                 i = le32_to_cpu(es->s_flags);
4185                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4186                         sbi->s_hash_unsigned = 3;
4187                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4188 #ifdef __CHAR_UNSIGNED__
4189                         if (!sb_rdonly(sb))
4190                                 es->s_flags |=
4191                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4192                         sbi->s_hash_unsigned = 3;
4193 #else
4194                         if (!sb_rdonly(sb))
4195                                 es->s_flags |=
4196                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4197 #endif
4198                 }
4199         }
4200
4201         /* Handle clustersize */
4202         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4203         has_bigalloc = ext4_has_feature_bigalloc(sb);
4204         if (has_bigalloc) {
4205                 if (clustersize < blocksize) {
4206                         ext4_msg(sb, KERN_ERR,
4207                                  "cluster size (%d) smaller than "
4208                                  "block size (%d)", clustersize, blocksize);
4209                         goto failed_mount;
4210                 }
4211                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4212                         le32_to_cpu(es->s_log_block_size);
4213                 sbi->s_clusters_per_group =
4214                         le32_to_cpu(es->s_clusters_per_group);
4215                 if (sbi->s_clusters_per_group > blocksize * 8) {
4216                         ext4_msg(sb, KERN_ERR,
4217                                  "#clusters per group too big: %lu",
4218                                  sbi->s_clusters_per_group);
4219                         goto failed_mount;
4220                 }
4221                 if (sbi->s_blocks_per_group !=
4222                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4223                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4224                                  "clusters per group (%lu) inconsistent",
4225                                  sbi->s_blocks_per_group,
4226                                  sbi->s_clusters_per_group);
4227                         goto failed_mount;
4228                 }
4229         } else {
4230                 if (clustersize != blocksize) {
4231                         ext4_msg(sb, KERN_ERR,
4232                                  "fragment/cluster size (%d) != "
4233                                  "block size (%d)", clustersize, blocksize);
4234                         goto failed_mount;
4235                 }
4236                 if (sbi->s_blocks_per_group > blocksize * 8) {
4237                         ext4_msg(sb, KERN_ERR,
4238                                  "#blocks per group too big: %lu",
4239                                  sbi->s_blocks_per_group);
4240                         goto failed_mount;
4241                 }
4242                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4243                 sbi->s_cluster_bits = 0;
4244         }
4245         sbi->s_cluster_ratio = clustersize / blocksize;
4246
4247         /* Do we have standard group size of clustersize * 8 blocks ? */
4248         if (sbi->s_blocks_per_group == clustersize << 3)
4249                 set_opt2(sb, STD_GROUP_SIZE);
4250
4251         /*
4252          * Test whether we have more sectors than will fit in sector_t,
4253          * and whether the max offset is addressable by the page cache.
4254          */
4255         err = generic_check_addressable(sb->s_blocksize_bits,
4256                                         ext4_blocks_count(es));
4257         if (err) {
4258                 ext4_msg(sb, KERN_ERR, "filesystem"
4259                          " too large to mount safely on this system");
4260                 goto failed_mount;
4261         }
4262
4263         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4264                 goto cantfind_ext4;
4265
4266         /* check blocks count against device size */
4267         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4268         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4269                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4270                        "exceeds size of device (%llu blocks)",
4271                        ext4_blocks_count(es), blocks_count);
4272                 goto failed_mount;
4273         }
4274
4275         /*
4276          * It makes no sense for the first data block to be beyond the end
4277          * of the filesystem.
4278          */
4279         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4280                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4281                          "block %u is beyond end of filesystem (%llu)",
4282                          le32_to_cpu(es->s_first_data_block),
4283                          ext4_blocks_count(es));
4284                 goto failed_mount;
4285         }
4286         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4287             (sbi->s_cluster_ratio == 1)) {
4288                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4289                          "block is 0 with a 1k block and cluster size");
4290                 goto failed_mount;
4291         }
4292
4293         blocks_count = (ext4_blocks_count(es) -
4294                         le32_to_cpu(es->s_first_data_block) +
4295                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4296         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4297         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4298                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4299                        "(block count %llu, first data block %u, "
4300                        "blocks per group %lu)", blocks_count,
4301                        ext4_blocks_count(es),
4302                        le32_to_cpu(es->s_first_data_block),
4303                        EXT4_BLOCKS_PER_GROUP(sb));
4304                 goto failed_mount;
4305         }
4306         sbi->s_groups_count = blocks_count;
4307         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4308                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4309         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4310             le32_to_cpu(es->s_inodes_count)) {
4311                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4312                          le32_to_cpu(es->s_inodes_count),
4313                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4314                 ret = -EINVAL;
4315                 goto failed_mount;
4316         }
4317         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4318                    EXT4_DESC_PER_BLOCK(sb);
4319         if (ext4_has_feature_meta_bg(sb)) {
4320                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4321                         ext4_msg(sb, KERN_WARNING,
4322                                  "first meta block group too large: %u "
4323                                  "(group descriptor block count %u)",
4324                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4325                         goto failed_mount;
4326                 }
4327         }
4328         rcu_assign_pointer(sbi->s_group_desc,
4329                            kvmalloc_array(db_count,
4330                                           sizeof(struct buffer_head *),
4331                                           GFP_KERNEL));
4332         if (sbi->s_group_desc == NULL) {
4333                 ext4_msg(sb, KERN_ERR, "not enough memory");
4334                 ret = -ENOMEM;
4335                 goto failed_mount;
4336         }
4337
4338         bgl_lock_init(sbi->s_blockgroup_lock);
4339
4340         /* Pre-read the descriptors into the buffer cache */
4341         for (i = 0; i < db_count; i++) {
4342                 block = descriptor_loc(sb, logical_sb_block, i);
4343                 sb_breadahead(sb, block);
4344         }
4345
4346         for (i = 0; i < db_count; i++) {
4347                 struct buffer_head *bh;
4348
4349                 block = descriptor_loc(sb, logical_sb_block, i);
4350                 bh = sb_bread_unmovable(sb, block);
4351                 if (!bh) {
4352                         ext4_msg(sb, KERN_ERR,
4353                                "can't read group descriptor %d", i);
4354                         db_count = i;
4355                         goto failed_mount2;
4356                 }
4357                 rcu_read_lock();
4358                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4359                 rcu_read_unlock();
4360         }
4361         sbi->s_gdb_count = db_count;
4362         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4363                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4364                 ret = -EFSCORRUPTED;
4365                 goto failed_mount2;
4366         }
4367
4368         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4369
4370         /* Register extent status tree shrinker */
4371         if (ext4_es_register_shrinker(sbi))
4372                 goto failed_mount3;
4373
4374         sbi->s_stripe = ext4_get_stripe_size(sbi);
4375         sbi->s_extent_max_zeroout_kb = 32;
4376
4377         /*
4378          * set up enough so that it can read an inode
4379          */
4380         sb->s_op = &ext4_sops;
4381         sb->s_export_op = &ext4_export_ops;
4382         sb->s_xattr = ext4_xattr_handlers;
4383 #ifdef CONFIG_FS_ENCRYPTION
4384         sb->s_cop = &ext4_cryptops;
4385 #endif
4386 #ifdef CONFIG_FS_VERITY
4387         sb->s_vop = &ext4_verityops;
4388 #endif
4389 #ifdef CONFIG_QUOTA
4390         sb->dq_op = &ext4_quota_operations;
4391         if (ext4_has_feature_quota(sb))
4392                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4393         else
4394                 sb->s_qcop = &ext4_qctl_operations;
4395         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4396 #endif
4397         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4398
4399         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4400         mutex_init(&sbi->s_orphan_lock);
4401
4402         sb->s_root = NULL;
4403
4404         needs_recovery = (es->s_last_orphan != 0 ||
4405                           ext4_has_feature_journal_needs_recovery(sb));
4406
4407         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4408                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4409                         goto failed_mount3a;
4410
4411         /*
4412          * The first inode we look at is the journal inode.  Don't try
4413          * root first: it may be modified in the journal!
4414          */
4415         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4416                 err = ext4_load_journal(sb, es, journal_devnum);
4417                 if (err)
4418                         goto failed_mount3a;
4419         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4420                    ext4_has_feature_journal_needs_recovery(sb)) {
4421                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4422                        "suppressed and not mounted read-only");
4423                 goto failed_mount_wq;
4424         } else {
4425                 /* Nojournal mode, all journal mount options are illegal */
4426                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4427                         ext4_msg(sb, KERN_ERR, "can't mount with "
4428                                  "journal_checksum, fs mounted w/o journal");
4429                         goto failed_mount_wq;
4430                 }
4431                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4432                         ext4_msg(sb, KERN_ERR, "can't mount with "
4433                                  "journal_async_commit, fs mounted w/o journal");
4434                         goto failed_mount_wq;
4435                 }
4436                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4437                         ext4_msg(sb, KERN_ERR, "can't mount with "
4438                                  "commit=%lu, fs mounted w/o journal",
4439                                  sbi->s_commit_interval / HZ);
4440                         goto failed_mount_wq;
4441                 }
4442                 if (EXT4_MOUNT_DATA_FLAGS &
4443                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4444                         ext4_msg(sb, KERN_ERR, "can't mount with "
4445                                  "data=, fs mounted w/o journal");
4446                         goto failed_mount_wq;
4447                 }
4448                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4449                 clear_opt(sb, JOURNAL_CHECKSUM);
4450                 clear_opt(sb, DATA_FLAGS);
4451                 sbi->s_journal = NULL;
4452                 needs_recovery = 0;
4453                 goto no_journal;
4454         }
4455
4456         if (ext4_has_feature_64bit(sb) &&
4457             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4458                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4459                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4460                 goto failed_mount_wq;
4461         }
4462
4463         if (!set_journal_csum_feature_set(sb)) {
4464                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4465                          "feature set");
4466                 goto failed_mount_wq;
4467         }
4468
4469         /* We have now updated the journal if required, so we can
4470          * validate the data journaling mode. */
4471         switch (test_opt(sb, DATA_FLAGS)) {
4472         case 0:
4473                 /* No mode set, assume a default based on the journal
4474                  * capabilities: ORDERED_DATA if the journal can
4475                  * cope, else JOURNAL_DATA
4476                  */
4477                 if (jbd2_journal_check_available_features
4478                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4479                         set_opt(sb, ORDERED_DATA);
4480                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4481                 } else {
4482                         set_opt(sb, JOURNAL_DATA);
4483                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4484                 }
4485                 break;
4486
4487         case EXT4_MOUNT_ORDERED_DATA:
4488         case EXT4_MOUNT_WRITEBACK_DATA:
4489                 if (!jbd2_journal_check_available_features
4490                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4491                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4492                                "requested data journaling mode");
4493                         goto failed_mount_wq;
4494                 }
4495         default:
4496                 break;
4497         }
4498
4499         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4500             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4501                 ext4_msg(sb, KERN_ERR, "can't mount with "
4502                         "journal_async_commit in data=ordered mode");
4503                 goto failed_mount_wq;
4504         }
4505
4506         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4507
4508         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4509
4510 no_journal:
4511         if (!test_opt(sb, NO_MBCACHE)) {
4512                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4513                 if (!sbi->s_ea_block_cache) {
4514                         ext4_msg(sb, KERN_ERR,
4515                                  "Failed to create ea_block_cache");
4516                         goto failed_mount_wq;
4517                 }
4518
4519                 if (ext4_has_feature_ea_inode(sb)) {
4520                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4521                         if (!sbi->s_ea_inode_cache) {
4522                                 ext4_msg(sb, KERN_ERR,
4523                                          "Failed to create ea_inode_cache");
4524                                 goto failed_mount_wq;
4525                         }
4526                 }
4527         }
4528
4529         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4530                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4531                 goto failed_mount_wq;
4532         }
4533
4534         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4535             !ext4_has_feature_encrypt(sb)) {
4536                 ext4_set_feature_encrypt(sb);
4537                 ext4_commit_super(sb, 1);
4538         }
4539
4540         /*
4541          * Get the # of file system overhead blocks from the
4542          * superblock if present.
4543          */
4544         if (es->s_overhead_clusters)
4545                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4546         else {
4547                 err = ext4_calculate_overhead(sb);
4548                 if (err)
4549                         goto failed_mount_wq;
4550         }
4551
4552         /*
4553          * The maximum number of concurrent works can be high and
4554          * concurrency isn't really necessary.  Limit it to 1.
4555          */
4556         EXT4_SB(sb)->rsv_conversion_wq =
4557                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4558         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4559                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4560                 ret = -ENOMEM;
4561                 goto failed_mount4;
4562         }
4563
4564         /*
4565          * The jbd2_journal_load will have done any necessary log recovery,
4566          * so we can safely mount the rest of the filesystem now.
4567          */
4568
4569         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4570         if (IS_ERR(root)) {
4571                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4572                 ret = PTR_ERR(root);
4573                 root = NULL;
4574                 goto failed_mount4;
4575         }
4576         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4577                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4578                 iput(root);
4579                 goto failed_mount4;
4580         }
4581
4582 #ifdef CONFIG_UNICODE
4583         if (sbi->s_encoding)
4584                 sb->s_d_op = &ext4_dentry_ops;
4585 #endif
4586
4587         sb->s_root = d_make_root(root);
4588         if (!sb->s_root) {
4589                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4590                 ret = -ENOMEM;
4591                 goto failed_mount4;
4592         }
4593
4594         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4595         if (ret == -EROFS) {
4596                 sb->s_flags |= SB_RDONLY;
4597                 ret = 0;
4598         } else if (ret)
4599                 goto failed_mount4a;
4600
4601         ext4_set_resv_clusters(sb);
4602
4603         err = ext4_setup_system_zone(sb);
4604         if (err) {
4605                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4606                          "zone (%d)", err);
4607                 goto failed_mount4a;
4608         }
4609
4610         ext4_ext_init(sb);
4611         err = ext4_mb_init(sb);
4612         if (err) {
4613                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4614                          err);
4615                 goto failed_mount5;
4616         }
4617
4618         block = ext4_count_free_clusters(sb);
4619         ext4_free_blocks_count_set(sbi->s_es,
4620                                    EXT4_C2B(sbi, block));
4621         ext4_superblock_csum_set(sb);
4622         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4623                                   GFP_KERNEL);
4624         if (!err) {
4625                 unsigned long freei = ext4_count_free_inodes(sb);
4626                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4627                 ext4_superblock_csum_set(sb);
4628                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4629                                           GFP_KERNEL);
4630         }
4631         if (!err)
4632                 err = percpu_counter_init(&sbi->s_dirs_counter,
4633                                           ext4_count_dirs(sb), GFP_KERNEL);
4634         if (!err)
4635                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4636                                           GFP_KERNEL);
4637         if (!err)
4638                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4639
4640         if (err) {
4641                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4642                 goto failed_mount6;
4643         }
4644
4645         if (ext4_has_feature_flex_bg(sb))
4646                 if (!ext4_fill_flex_info(sb)) {
4647                         ext4_msg(sb, KERN_ERR,
4648                                "unable to initialize "
4649                                "flex_bg meta info!");
4650                         goto failed_mount6;
4651                 }
4652
4653         err = ext4_register_li_request(sb, first_not_zeroed);
4654         if (err)
4655                 goto failed_mount6;
4656
4657         err = ext4_register_sysfs(sb);
4658         if (err)
4659                 goto failed_mount7;
4660
4661 #ifdef CONFIG_QUOTA
4662         /* Enable quota usage during mount. */
4663         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4664                 err = ext4_enable_quotas(sb);
4665                 if (err)
4666                         goto failed_mount8;
4667         }
4668 #endif  /* CONFIG_QUOTA */
4669
4670         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4671         ext4_orphan_cleanup(sb, es);
4672         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4673         if (needs_recovery) {
4674                 ext4_msg(sb, KERN_INFO, "recovery complete");
4675                 ext4_mark_recovery_complete(sb, es);
4676         }
4677         if (EXT4_SB(sb)->s_journal) {
4678                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4679                         descr = " journalled data mode";
4680                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4681                         descr = " ordered data mode";
4682                 else
4683                         descr = " writeback data mode";
4684         } else
4685                 descr = "out journal";
4686
4687         if (test_opt(sb, DISCARD)) {
4688                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4689                 if (!blk_queue_discard(q))
4690                         ext4_msg(sb, KERN_WARNING,
4691                                  "mounting with \"discard\" option, but "
4692                                  "the device does not support discard");
4693         }
4694
4695         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4696                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4697                          "Opts: %.*s%s%s", descr,
4698                          (int) sizeof(sbi->s_es->s_mount_opts),
4699                          sbi->s_es->s_mount_opts,
4700                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4701
4702         if (es->s_error_count)
4703                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4704
4705         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4706         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4707         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4708         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4709
4710         kfree(orig_data);
4711         return 0;
4712
4713 cantfind_ext4:
4714         if (!silent)
4715                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4716         goto failed_mount;
4717
4718 #ifdef CONFIG_QUOTA
4719 failed_mount8:
4720         ext4_unregister_sysfs(sb);
4721 #endif
4722 failed_mount7:
4723         ext4_unregister_li_request(sb);
4724 failed_mount6:
4725         ext4_mb_release(sb);
4726         rcu_read_lock();
4727         flex_groups = rcu_dereference(sbi->s_flex_groups);
4728         if (flex_groups) {
4729                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
4730                         kvfree(flex_groups[i]);
4731                 kvfree(flex_groups);
4732         }
4733         rcu_read_unlock();
4734         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4735         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4736         percpu_counter_destroy(&sbi->s_dirs_counter);
4737         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4738         percpu_free_rwsem(&sbi->s_writepages_rwsem);
4739 failed_mount5:
4740         ext4_ext_release(sb);
4741         ext4_release_system_zone(sb);
4742 failed_mount4a:
4743         dput(sb->s_root);
4744         sb->s_root = NULL;
4745 failed_mount4:
4746         ext4_msg(sb, KERN_ERR, "mount failed");
4747         if (EXT4_SB(sb)->rsv_conversion_wq)
4748                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4749 failed_mount_wq:
4750         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4751         sbi->s_ea_inode_cache = NULL;
4752
4753         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4754         sbi->s_ea_block_cache = NULL;
4755
4756         if (sbi->s_journal) {
4757                 jbd2_journal_destroy(sbi->s_journal);
4758                 sbi->s_journal = NULL;
4759         }
4760 failed_mount3a:
4761         ext4_es_unregister_shrinker(sbi);
4762 failed_mount3:
4763         del_timer_sync(&sbi->s_err_report);
4764         if (sbi->s_mmp_tsk)
4765                 kthread_stop(sbi->s_mmp_tsk);
4766 failed_mount2:
4767         rcu_read_lock();
4768         group_desc = rcu_dereference(sbi->s_group_desc);
4769         for (i = 0; i < db_count; i++)
4770                 brelse(group_desc[i]);
4771         kvfree(group_desc);
4772         rcu_read_unlock();
4773 failed_mount:
4774         if (sbi->s_chksum_driver)
4775                 crypto_free_shash(sbi->s_chksum_driver);
4776
4777 #ifdef CONFIG_UNICODE
4778         utf8_unload(sbi->s_encoding);
4779 #endif
4780
4781 #ifdef CONFIG_QUOTA
4782         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4783                 kfree(get_qf_name(sb, sbi, i));
4784 #endif
4785         ext4_blkdev_remove(sbi);
4786         brelse(bh);
4787 out_fail:
4788         sb->s_fs_info = NULL;
4789         kfree(sbi->s_blockgroup_lock);
4790 out_free_base:
4791         kfree(sbi);
4792         kfree(orig_data);
4793         fs_put_dax(dax_dev);
4794         return err ? err : ret;
4795 }
4796
4797 /*
4798  * Setup any per-fs journal parameters now.  We'll do this both on
4799  * initial mount, once the journal has been initialised but before we've
4800  * done any recovery; and again on any subsequent remount.
4801  */
4802 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4803 {
4804         struct ext4_sb_info *sbi = EXT4_SB(sb);
4805
4806         journal->j_commit_interval = sbi->s_commit_interval;
4807         journal->j_min_batch_time = sbi->s_min_batch_time;
4808         journal->j_max_batch_time = sbi->s_max_batch_time;
4809
4810         write_lock(&journal->j_state_lock);
4811         if (test_opt(sb, BARRIER))
4812                 journal->j_flags |= JBD2_BARRIER;
4813         else
4814                 journal->j_flags &= ~JBD2_BARRIER;
4815         if (test_opt(sb, DATA_ERR_ABORT))
4816                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4817         else
4818                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4819         write_unlock(&journal->j_state_lock);
4820 }
4821
4822 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4823                                              unsigned int journal_inum)
4824 {
4825         struct inode *journal_inode;
4826
4827         /*
4828          * Test for the existence of a valid inode on disk.  Bad things
4829          * happen if we iget() an unused inode, as the subsequent iput()
4830          * will try to delete it.
4831          */
4832         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4833         if (IS_ERR(journal_inode)) {
4834                 ext4_msg(sb, KERN_ERR, "no journal found");
4835                 return NULL;
4836         }
4837         if (!journal_inode->i_nlink) {
4838                 make_bad_inode(journal_inode);
4839                 iput(journal_inode);
4840                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4841                 return NULL;
4842         }
4843
4844         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4845                   journal_inode, journal_inode->i_size);
4846         if (!S_ISREG(journal_inode->i_mode)) {
4847                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4848                 iput(journal_inode);
4849                 return NULL;
4850         }
4851         return journal_inode;
4852 }
4853
4854 static journal_t *ext4_get_journal(struct super_block *sb,
4855                                    unsigned int journal_inum)
4856 {
4857         struct inode *journal_inode;
4858         journal_t *journal;
4859
4860         BUG_ON(!ext4_has_feature_journal(sb));
4861
4862         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4863         if (!journal_inode)
4864                 return NULL;
4865
4866         journal = jbd2_journal_init_inode(journal_inode);
4867         if (!journal) {
4868                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4869                 iput(journal_inode);
4870                 return NULL;
4871         }
4872         journal->j_private = sb;
4873         ext4_init_journal_params(sb, journal);
4874         return journal;
4875 }
4876
4877 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4878                                        dev_t j_dev)
4879 {
4880         struct buffer_head *bh;
4881         journal_t *journal;
4882         ext4_fsblk_t start;
4883         ext4_fsblk_t len;
4884         int hblock, blocksize;
4885         ext4_fsblk_t sb_block;
4886         unsigned long offset;
4887         struct ext4_super_block *es;
4888         struct block_device *bdev;
4889
4890         BUG_ON(!ext4_has_feature_journal(sb));
4891
4892         bdev = ext4_blkdev_get(j_dev, sb);
4893         if (bdev == NULL)
4894                 return NULL;
4895
4896         blocksize = sb->s_blocksize;
4897         hblock = bdev_logical_block_size(bdev);
4898         if (blocksize < hblock) {
4899                 ext4_msg(sb, KERN_ERR,
4900                         "blocksize too small for journal device");
4901                 goto out_bdev;
4902         }
4903
4904         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4905         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4906         set_blocksize(bdev, blocksize);
4907         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4908                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4909                        "external journal");
4910                 goto out_bdev;
4911         }
4912
4913         es = (struct ext4_super_block *) (bh->b_data + offset);
4914         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4915             !(le32_to_cpu(es->s_feature_incompat) &
4916               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4917                 ext4_msg(sb, KERN_ERR, "external journal has "
4918                                         "bad superblock");
4919                 brelse(bh);
4920                 goto out_bdev;
4921         }
4922
4923         if ((le32_to_cpu(es->s_feature_ro_compat) &
4924              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4925             es->s_checksum != ext4_superblock_csum(sb, es)) {
4926                 ext4_msg(sb, KERN_ERR, "external journal has "
4927                                        "corrupt superblock");
4928                 brelse(bh);
4929                 goto out_bdev;
4930         }
4931
4932         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4933                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4934                 brelse(bh);
4935                 goto out_bdev;
4936         }
4937
4938         len = ext4_blocks_count(es);
4939         start = sb_block + 1;
4940         brelse(bh);     /* we're done with the superblock */
4941
4942         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4943                                         start, len, blocksize);
4944         if (!journal) {
4945                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4946                 goto out_bdev;
4947         }
4948         journal->j_private = sb;
4949         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4950         wait_on_buffer(journal->j_sb_buffer);
4951         if (!buffer_uptodate(journal->j_sb_buffer)) {
4952                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4953                 goto out_journal;
4954         }
4955         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4956                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4957                                         "user (unsupported) - %d",
4958                         be32_to_cpu(journal->j_superblock->s_nr_users));
4959                 goto out_journal;
4960         }
4961         EXT4_SB(sb)->journal_bdev = bdev;
4962         ext4_init_journal_params(sb, journal);
4963         return journal;
4964
4965 out_journal:
4966         jbd2_journal_destroy(journal);
4967 out_bdev:
4968         ext4_blkdev_put(bdev);
4969         return NULL;
4970 }
4971
4972 static int ext4_load_journal(struct super_block *sb,
4973                              struct ext4_super_block *es,
4974                              unsigned long journal_devnum)
4975 {
4976         journal_t *journal;
4977         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4978         dev_t journal_dev;
4979         int err = 0;
4980         int really_read_only;
4981
4982         BUG_ON(!ext4_has_feature_journal(sb));
4983
4984         if (journal_devnum &&
4985             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4986                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4987                         "numbers have changed");
4988                 journal_dev = new_decode_dev(journal_devnum);
4989         } else
4990                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4991
4992         really_read_only = bdev_read_only(sb->s_bdev);
4993
4994         /*
4995          * Are we loading a blank journal or performing recovery after a
4996          * crash?  For recovery, we need to check in advance whether we
4997          * can get read-write access to the device.
4998          */
4999         if (ext4_has_feature_journal_needs_recovery(sb)) {
5000                 if (sb_rdonly(sb)) {
5001                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5002                                         "required on readonly filesystem");
5003                         if (really_read_only) {
5004                                 ext4_msg(sb, KERN_ERR, "write access "
5005                                         "unavailable, cannot proceed "
5006                                         "(try mounting with noload)");
5007                                 return -EROFS;
5008                         }
5009                         ext4_msg(sb, KERN_INFO, "write access will "
5010                                "be enabled during recovery");
5011                 }
5012         }
5013
5014         if (journal_inum && journal_dev) {
5015                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
5016                        "and inode journals!");
5017                 return -EINVAL;
5018         }
5019
5020         if (journal_inum) {
5021                 if (!(journal = ext4_get_journal(sb, journal_inum)))
5022                         return -EINVAL;
5023         } else {
5024                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
5025                         return -EINVAL;
5026         }
5027
5028         if (!(journal->j_flags & JBD2_BARRIER))
5029                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5030
5031         if (!ext4_has_feature_journal_needs_recovery(sb))
5032                 err = jbd2_journal_wipe(journal, !really_read_only);
5033         if (!err) {
5034                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5035                 if (save)
5036                         memcpy(save, ((char *) es) +
5037                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5038                 err = jbd2_journal_load(journal);
5039                 if (save)
5040                         memcpy(((char *) es) + EXT4_S_ERR_START,
5041                                save, EXT4_S_ERR_LEN);
5042                 kfree(save);
5043         }
5044
5045         if (err) {
5046                 ext4_msg(sb, KERN_ERR, "error loading journal");
5047                 jbd2_journal_destroy(journal);
5048                 return err;
5049         }
5050
5051         EXT4_SB(sb)->s_journal = journal;
5052         ext4_clear_journal_err(sb, es);
5053
5054         if (!really_read_only && journal_devnum &&
5055             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5056                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5057
5058                 /* Make sure we flush the recovery flag to disk. */
5059                 ext4_commit_super(sb, 1);
5060         }
5061
5062         return 0;
5063 }
5064
5065 static int ext4_commit_super(struct super_block *sb, int sync)
5066 {
5067         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5068         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5069         int error = 0;
5070
5071         if (!sbh || block_device_ejected(sb))
5072                 return error;
5073
5074         /*
5075          * The superblock bh should be mapped, but it might not be if the
5076          * device was hot-removed. Not much we can do but fail the I/O.
5077          */
5078         if (!buffer_mapped(sbh))
5079                 return error;
5080
5081         /*
5082          * If the file system is mounted read-only, don't update the
5083          * superblock write time.  This avoids updating the superblock
5084          * write time when we are mounting the root file system
5085          * read/only but we need to replay the journal; at that point,
5086          * for people who are east of GMT and who make their clock
5087          * tick in localtime for Windows bug-for-bug compatibility,
5088          * the clock is set in the future, and this will cause e2fsck
5089          * to complain and force a full file system check.
5090          */
5091         if (!(sb->s_flags & SB_RDONLY))
5092                 ext4_update_tstamp(es, s_wtime);
5093         if (sb->s_bdev->bd_part)
5094                 es->s_kbytes_written =
5095                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5096                             ((part_stat_read(sb->s_bdev->bd_part,
5097                                              sectors[STAT_WRITE]) -
5098                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5099         else
5100                 es->s_kbytes_written =
5101                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5102         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5103                 ext4_free_blocks_count_set(es,
5104                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5105                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5106         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5107                 es->s_free_inodes_count =
5108                         cpu_to_le32(percpu_counter_sum_positive(
5109                                 &EXT4_SB(sb)->s_freeinodes_counter));
5110         BUFFER_TRACE(sbh, "marking dirty");
5111         ext4_superblock_csum_set(sb);
5112         if (sync)
5113                 lock_buffer(sbh);
5114         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5115                 /*
5116                  * Oh, dear.  A previous attempt to write the
5117                  * superblock failed.  This could happen because the
5118                  * USB device was yanked out.  Or it could happen to
5119                  * be a transient write error and maybe the block will
5120                  * be remapped.  Nothing we can do but to retry the
5121                  * write and hope for the best.
5122                  */
5123                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5124                        "superblock detected");
5125                 clear_buffer_write_io_error(sbh);
5126                 set_buffer_uptodate(sbh);
5127         }
5128         mark_buffer_dirty(sbh);
5129         if (sync) {
5130                 unlock_buffer(sbh);
5131                 error = __sync_dirty_buffer(sbh,
5132                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5133                 if (buffer_write_io_error(sbh)) {
5134                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5135                                "superblock");
5136                         clear_buffer_write_io_error(sbh);
5137                         set_buffer_uptodate(sbh);
5138                 }
5139         }
5140         return error;
5141 }
5142
5143 /*
5144  * Have we just finished recovery?  If so, and if we are mounting (or
5145  * remounting) the filesystem readonly, then we will end up with a
5146  * consistent fs on disk.  Record that fact.
5147  */
5148 static void ext4_mark_recovery_complete(struct super_block *sb,
5149                                         struct ext4_super_block *es)
5150 {
5151         journal_t *journal = EXT4_SB(sb)->s_journal;
5152
5153         if (!ext4_has_feature_journal(sb)) {
5154                 BUG_ON(journal != NULL);
5155                 return;
5156         }
5157         jbd2_journal_lock_updates(journal);
5158         if (jbd2_journal_flush(journal) < 0)
5159                 goto out;
5160
5161         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5162                 ext4_clear_feature_journal_needs_recovery(sb);
5163                 ext4_commit_super(sb, 1);
5164         }
5165
5166 out:
5167         jbd2_journal_unlock_updates(journal);
5168 }
5169
5170 /*
5171  * If we are mounting (or read-write remounting) a filesystem whose journal
5172  * has recorded an error from a previous lifetime, move that error to the
5173  * main filesystem now.
5174  */
5175 static void ext4_clear_journal_err(struct super_block *sb,
5176                                    struct ext4_super_block *es)
5177 {
5178         journal_t *journal;
5179         int j_errno;
5180         const char *errstr;
5181
5182         BUG_ON(!ext4_has_feature_journal(sb));
5183
5184         journal = EXT4_SB(sb)->s_journal;
5185
5186         /*
5187          * Now check for any error status which may have been recorded in the
5188          * journal by a prior ext4_error() or ext4_abort()
5189          */
5190
5191         j_errno = jbd2_journal_errno(journal);
5192         if (j_errno) {
5193                 char nbuf[16];
5194
5195                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5196                 ext4_warning(sb, "Filesystem error recorded "
5197                              "from previous mount: %s", errstr);
5198                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5199
5200                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5201                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5202                 ext4_commit_super(sb, 1);
5203
5204                 jbd2_journal_clear_err(journal);
5205                 jbd2_journal_update_sb_errno(journal);
5206         }
5207 }
5208
5209 /*
5210  * Force the running and committing transactions to commit,
5211  * and wait on the commit.
5212  */
5213 int ext4_force_commit(struct super_block *sb)
5214 {
5215         journal_t *journal;
5216
5217         if (sb_rdonly(sb))
5218                 return 0;
5219
5220         journal = EXT4_SB(sb)->s_journal;
5221         return ext4_journal_force_commit(journal);
5222 }
5223
5224 static int ext4_sync_fs(struct super_block *sb, int wait)
5225 {
5226         int ret = 0;
5227         tid_t target;
5228         bool needs_barrier = false;
5229         struct ext4_sb_info *sbi = EXT4_SB(sb);
5230
5231         if (unlikely(ext4_forced_shutdown(sbi)))
5232                 return 0;
5233
5234         trace_ext4_sync_fs(sb, wait);
5235         flush_workqueue(sbi->rsv_conversion_wq);
5236         /*
5237          * Writeback quota in non-journalled quota case - journalled quota has
5238          * no dirty dquots
5239          */
5240         dquot_writeback_dquots(sb, -1);
5241         /*
5242          * Data writeback is possible w/o journal transaction, so barrier must
5243          * being sent at the end of the function. But we can skip it if
5244          * transaction_commit will do it for us.
5245          */
5246         if (sbi->s_journal) {
5247                 target = jbd2_get_latest_transaction(sbi->s_journal);
5248                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5249                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5250                         needs_barrier = true;
5251
5252                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5253                         if (wait)
5254                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5255                                                            target);
5256                 }
5257         } else if (wait && test_opt(sb, BARRIER))
5258                 needs_barrier = true;
5259         if (needs_barrier) {
5260                 int err;
5261                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
5262                 if (!ret)
5263                         ret = err;
5264         }
5265
5266         return ret;
5267 }
5268
5269 /*
5270  * LVM calls this function before a (read-only) snapshot is created.  This
5271  * gives us a chance to flush the journal completely and mark the fs clean.
5272  *
5273  * Note that only this function cannot bring a filesystem to be in a clean
5274  * state independently. It relies on upper layer to stop all data & metadata
5275  * modifications.
5276  */
5277 static int ext4_freeze(struct super_block *sb)
5278 {
5279         int error = 0;
5280         journal_t *journal;
5281
5282         if (sb_rdonly(sb))
5283                 return 0;
5284
5285         journal = EXT4_SB(sb)->s_journal;
5286
5287         if (journal) {
5288                 /* Now we set up the journal barrier. */
5289                 jbd2_journal_lock_updates(journal);
5290
5291                 /*
5292                  * Don't clear the needs_recovery flag if we failed to
5293                  * flush the journal.
5294                  */
5295                 error = jbd2_journal_flush(journal);
5296                 if (error < 0)
5297                         goto out;
5298
5299                 /* Journal blocked and flushed, clear needs_recovery flag. */
5300                 ext4_clear_feature_journal_needs_recovery(sb);
5301         }
5302
5303         error = ext4_commit_super(sb, 1);
5304 out:
5305         if (journal)
5306                 /* we rely on upper layer to stop further updates */
5307                 jbd2_journal_unlock_updates(journal);
5308         return error;
5309 }
5310
5311 /*
5312  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5313  * flag here, even though the filesystem is not technically dirty yet.
5314  */
5315 static int ext4_unfreeze(struct super_block *sb)
5316 {
5317         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5318                 return 0;
5319
5320         if (EXT4_SB(sb)->s_journal) {
5321                 /* Reset the needs_recovery flag before the fs is unlocked. */
5322                 ext4_set_feature_journal_needs_recovery(sb);
5323         }
5324
5325         ext4_commit_super(sb, 1);
5326         return 0;
5327 }
5328
5329 /*
5330  * Structure to save mount options for ext4_remount's benefit
5331  */
5332 struct ext4_mount_options {
5333         unsigned long s_mount_opt;
5334         unsigned long s_mount_opt2;
5335         kuid_t s_resuid;
5336         kgid_t s_resgid;
5337         unsigned long s_commit_interval;
5338         u32 s_min_batch_time, s_max_batch_time;
5339 #ifdef CONFIG_QUOTA
5340         int s_jquota_fmt;
5341         char *s_qf_names[EXT4_MAXQUOTAS];
5342 #endif
5343 };
5344
5345 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5346 {
5347         struct ext4_super_block *es;
5348         struct ext4_sb_info *sbi = EXT4_SB(sb);
5349         unsigned long old_sb_flags;
5350         struct ext4_mount_options old_opts;
5351         int enable_quota = 0;
5352         ext4_group_t g;
5353         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5354         int err = 0;
5355 #ifdef CONFIG_QUOTA
5356         int i, j;
5357         char *to_free[EXT4_MAXQUOTAS];
5358 #endif
5359         char *orig_data = kstrdup(data, GFP_KERNEL);
5360
5361         if (data && !orig_data)
5362                 return -ENOMEM;
5363
5364         /* Store the original options */
5365         old_sb_flags = sb->s_flags;
5366         old_opts.s_mount_opt = sbi->s_mount_opt;
5367         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5368         old_opts.s_resuid = sbi->s_resuid;
5369         old_opts.s_resgid = sbi->s_resgid;
5370         old_opts.s_commit_interval = sbi->s_commit_interval;
5371         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5372         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5373 #ifdef CONFIG_QUOTA
5374         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5375         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5376                 if (sbi->s_qf_names[i]) {
5377                         char *qf_name = get_qf_name(sb, sbi, i);
5378
5379                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5380                         if (!old_opts.s_qf_names[i]) {
5381                                 for (j = 0; j < i; j++)
5382                                         kfree(old_opts.s_qf_names[j]);
5383                                 kfree(orig_data);
5384                                 return -ENOMEM;
5385                         }
5386                 } else
5387                         old_opts.s_qf_names[i] = NULL;
5388 #endif
5389         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5390                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5391
5392         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5393                 err = -EINVAL;
5394                 goto restore_opts;
5395         }
5396
5397         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5398             test_opt(sb, JOURNAL_CHECKSUM)) {
5399                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5400                          "during remount not supported; ignoring");
5401                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5402         }
5403
5404         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5405                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5406                         ext4_msg(sb, KERN_ERR, "can't mount with "
5407                                  "both data=journal and delalloc");
5408                         err = -EINVAL;
5409                         goto restore_opts;
5410                 }
5411                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5412                         ext4_msg(sb, KERN_ERR, "can't mount with "
5413                                  "both data=journal and dioread_nolock");
5414                         err = -EINVAL;
5415                         goto restore_opts;
5416                 }
5417                 if (test_opt(sb, DAX)) {
5418                         ext4_msg(sb, KERN_ERR, "can't mount with "
5419                                  "both data=journal and dax");
5420                         err = -EINVAL;
5421                         goto restore_opts;
5422                 }
5423         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5424                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5425                         ext4_msg(sb, KERN_ERR, "can't mount with "
5426                                 "journal_async_commit in data=ordered mode");
5427                         err = -EINVAL;
5428                         goto restore_opts;
5429                 }
5430         }
5431
5432         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5433                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5434                 err = -EINVAL;
5435                 goto restore_opts;
5436         }
5437
5438         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5439                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5440                         "dax flag with busy inodes while remounting");
5441                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5442         }
5443
5444         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5445                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5446
5447         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5448                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5449
5450         es = sbi->s_es;
5451
5452         if (sbi->s_journal) {
5453                 ext4_init_journal_params(sb, sbi->s_journal);
5454                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5455         }
5456
5457         if (*flags & SB_LAZYTIME)
5458                 sb->s_flags |= SB_LAZYTIME;
5459
5460         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5461                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5462                         err = -EROFS;
5463                         goto restore_opts;
5464                 }
5465
5466                 if (*flags & SB_RDONLY) {
5467                         err = sync_filesystem(sb);
5468                         if (err < 0)
5469                                 goto restore_opts;
5470                         err = dquot_suspend(sb, -1);
5471                         if (err < 0)
5472                                 goto restore_opts;
5473
5474                         /*
5475                          * First of all, the unconditional stuff we have to do
5476                          * to disable replay of the journal when we next remount
5477                          */
5478                         sb->s_flags |= SB_RDONLY;
5479
5480                         /*
5481                          * OK, test if we are remounting a valid rw partition
5482                          * readonly, and if so set the rdonly flag and then
5483                          * mark the partition as valid again.
5484                          */
5485                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5486                             (sbi->s_mount_state & EXT4_VALID_FS))
5487                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5488
5489                         if (sbi->s_journal)
5490                                 ext4_mark_recovery_complete(sb, es);
5491                         if (sbi->s_mmp_tsk)
5492                                 kthread_stop(sbi->s_mmp_tsk);
5493                 } else {
5494                         /* Make sure we can mount this feature set readwrite */
5495                         if (ext4_has_feature_readonly(sb) ||
5496                             !ext4_feature_set_ok(sb, 0)) {
5497                                 err = -EROFS;
5498                                 goto restore_opts;
5499                         }
5500                         /*
5501                          * Make sure the group descriptor checksums
5502                          * are sane.  If they aren't, refuse to remount r/w.
5503                          */
5504                         for (g = 0; g < sbi->s_groups_count; g++) {
5505                                 struct ext4_group_desc *gdp =
5506                                         ext4_get_group_desc(sb, g, NULL);
5507
5508                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5509                                         ext4_msg(sb, KERN_ERR,
5510                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5511                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5512                                                le16_to_cpu(gdp->bg_checksum));
5513                                         err = -EFSBADCRC;
5514                                         goto restore_opts;
5515                                 }
5516                         }
5517
5518                         /*
5519                          * If we have an unprocessed orphan list hanging
5520                          * around from a previously readonly bdev mount,
5521                          * require a full umount/remount for now.
5522                          */
5523                         if (es->s_last_orphan) {
5524                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5525                                        "remount RDWR because of unprocessed "
5526                                        "orphan inode list.  Please "
5527                                        "umount/remount instead");
5528                                 err = -EINVAL;
5529                                 goto restore_opts;
5530                         }
5531
5532                         /*
5533                          * Mounting a RDONLY partition read-write, so reread
5534                          * and store the current valid flag.  (It may have
5535                          * been changed by e2fsck since we originally mounted
5536                          * the partition.)
5537                          */
5538                         if (sbi->s_journal)
5539                                 ext4_clear_journal_err(sb, es);
5540                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5541
5542                         err = ext4_setup_super(sb, es, 0);
5543                         if (err)
5544                                 goto restore_opts;
5545
5546                         sb->s_flags &= ~SB_RDONLY;
5547                         if (ext4_has_feature_mmp(sb))
5548                                 if (ext4_multi_mount_protect(sb,
5549                                                 le64_to_cpu(es->s_mmp_block))) {
5550                                         err = -EROFS;
5551                                         goto restore_opts;
5552                                 }
5553                         enable_quota = 1;
5554                 }
5555         }
5556
5557         /*
5558          * Reinitialize lazy itable initialization thread based on
5559          * current settings
5560          */
5561         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5562                 ext4_unregister_li_request(sb);
5563         else {
5564                 ext4_group_t first_not_zeroed;
5565                 first_not_zeroed = ext4_has_uninit_itable(sb);
5566                 ext4_register_li_request(sb, first_not_zeroed);
5567         }
5568
5569         ext4_setup_system_zone(sb);
5570         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5571                 err = ext4_commit_super(sb, 1);
5572                 if (err)
5573                         goto restore_opts;
5574         }
5575
5576 #ifdef CONFIG_QUOTA
5577         /* Release old quota file names */
5578         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5579                 kfree(old_opts.s_qf_names[i]);
5580         if (enable_quota) {
5581                 if (sb_any_quota_suspended(sb))
5582                         dquot_resume(sb, -1);
5583                 else if (ext4_has_feature_quota(sb)) {
5584                         err = ext4_enable_quotas(sb);
5585                         if (err)
5586                                 goto restore_opts;
5587                 }
5588         }
5589 #endif
5590
5591         *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5592         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5593         kfree(orig_data);
5594         return 0;
5595
5596 restore_opts:
5597         sb->s_flags = old_sb_flags;
5598         sbi->s_mount_opt = old_opts.s_mount_opt;
5599         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5600         sbi->s_resuid = old_opts.s_resuid;
5601         sbi->s_resgid = old_opts.s_resgid;
5602         sbi->s_commit_interval = old_opts.s_commit_interval;
5603         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5604         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5605 #ifdef CONFIG_QUOTA
5606         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5607         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5608                 to_free[i] = get_qf_name(sb, sbi, i);
5609                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5610         }
5611         synchronize_rcu();
5612         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5613                 kfree(to_free[i]);
5614 #endif
5615         kfree(orig_data);
5616         return err;
5617 }
5618
5619 #ifdef CONFIG_QUOTA
5620 static int ext4_statfs_project(struct super_block *sb,
5621                                kprojid_t projid, struct kstatfs *buf)
5622 {
5623         struct kqid qid;
5624         struct dquot *dquot;
5625         u64 limit;
5626         u64 curblock;
5627
5628         qid = make_kqid_projid(projid);
5629         dquot = dqget(sb, qid);
5630         if (IS_ERR(dquot))
5631                 return PTR_ERR(dquot);
5632         spin_lock(&dquot->dq_dqb_lock);
5633
5634         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
5635                              dquot->dq_dqb.dqb_bhardlimit);
5636         limit >>= sb->s_blocksize_bits;
5637
5638         if (limit && buf->f_blocks > limit) {
5639                 curblock = (dquot->dq_dqb.dqb_curspace +
5640                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5641                 buf->f_blocks = limit;
5642                 buf->f_bfree = buf->f_bavail =
5643                         (buf->f_blocks > curblock) ?
5644                          (buf->f_blocks - curblock) : 0;
5645         }
5646
5647         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
5648                              dquot->dq_dqb.dqb_ihardlimit);
5649         if (limit && buf->f_files > limit) {
5650                 buf->f_files = limit;
5651                 buf->f_ffree =
5652                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5653                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5654         }
5655
5656         spin_unlock(&dquot->dq_dqb_lock);
5657         dqput(dquot);
5658         return 0;
5659 }
5660 #endif
5661
5662 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5663 {
5664         struct super_block *sb = dentry->d_sb;
5665         struct ext4_sb_info *sbi = EXT4_SB(sb);
5666         struct ext4_super_block *es = sbi->s_es;
5667         ext4_fsblk_t overhead = 0, resv_blocks;
5668         u64 fsid;
5669         s64 bfree;
5670         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5671
5672         if (!test_opt(sb, MINIX_DF))
5673                 overhead = sbi->s_overhead;
5674
5675         buf->f_type = EXT4_SUPER_MAGIC;
5676         buf->f_bsize = sb->s_blocksize;
5677         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5678         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5679                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5680         /* prevent underflow in case that few free space is available */
5681         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5682         buf->f_bavail = buf->f_bfree -
5683                         (ext4_r_blocks_count(es) + resv_blocks);
5684         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5685                 buf->f_bavail = 0;
5686         buf->f_files = le32_to_cpu(es->s_inodes_count);
5687         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5688         buf->f_namelen = EXT4_NAME_LEN;
5689         fsid = le64_to_cpup((void *)es->s_uuid) ^
5690                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5691         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5692         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5693
5694 #ifdef CONFIG_QUOTA
5695         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5696             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5697                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5698 #endif
5699         return 0;
5700 }
5701
5702
5703 #ifdef CONFIG_QUOTA
5704
5705 /*
5706  * Helper functions so that transaction is started before we acquire dqio_sem
5707  * to keep correct lock ordering of transaction > dqio_sem
5708  */
5709 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5710 {
5711         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5712 }
5713
5714 static int ext4_write_dquot(struct dquot *dquot)
5715 {
5716         int ret, err;
5717         handle_t *handle;
5718         struct inode *inode;
5719
5720         inode = dquot_to_inode(dquot);
5721         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5722                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5723         if (IS_ERR(handle))
5724                 return PTR_ERR(handle);
5725         ret = dquot_commit(dquot);
5726         err = ext4_journal_stop(handle);
5727         if (!ret)
5728                 ret = err;
5729         return ret;
5730 }
5731
5732 static int ext4_acquire_dquot(struct dquot *dquot)
5733 {
5734         int ret, err;
5735         handle_t *handle;
5736
5737         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5738                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5739         if (IS_ERR(handle))
5740                 return PTR_ERR(handle);
5741         ret = dquot_acquire(dquot);
5742         err = ext4_journal_stop(handle);
5743         if (!ret)
5744                 ret = err;
5745         return ret;
5746 }
5747
5748 static int ext4_release_dquot(struct dquot *dquot)
5749 {
5750         int ret, err;
5751         handle_t *handle;
5752
5753         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5754                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5755         if (IS_ERR(handle)) {
5756                 /* Release dquot anyway to avoid endless cycle in dqput() */
5757                 dquot_release(dquot);
5758                 return PTR_ERR(handle);
5759         }
5760         ret = dquot_release(dquot);
5761         err = ext4_journal_stop(handle);
5762         if (!ret)
5763                 ret = err;
5764         return ret;
5765 }
5766
5767 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5768 {
5769         struct super_block *sb = dquot->dq_sb;
5770         struct ext4_sb_info *sbi = EXT4_SB(sb);
5771
5772         /* Are we journaling quotas? */
5773         if (ext4_has_feature_quota(sb) ||
5774             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5775                 dquot_mark_dquot_dirty(dquot);
5776                 return ext4_write_dquot(dquot);
5777         } else {
5778                 return dquot_mark_dquot_dirty(dquot);
5779         }
5780 }
5781
5782 static int ext4_write_info(struct super_block *sb, int type)
5783 {
5784         int ret, err;
5785         handle_t *handle;
5786
5787         /* Data block + inode block */
5788         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5789         if (IS_ERR(handle))
5790                 return PTR_ERR(handle);
5791         ret = dquot_commit_info(sb, type);
5792         err = ext4_journal_stop(handle);
5793         if (!ret)
5794                 ret = err;
5795         return ret;
5796 }
5797
5798 /*
5799  * Turn on quotas during mount time - we need to find
5800  * the quota file and such...
5801  */
5802 static int ext4_quota_on_mount(struct super_block *sb, int type)
5803 {
5804         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5805                                         EXT4_SB(sb)->s_jquota_fmt, type);
5806 }
5807
5808 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5809 {
5810         struct ext4_inode_info *ei = EXT4_I(inode);
5811
5812         /* The first argument of lockdep_set_subclass has to be
5813          * *exactly* the same as the argument to init_rwsem() --- in
5814          * this case, in init_once() --- or lockdep gets unhappy
5815          * because the name of the lock is set using the
5816          * stringification of the argument to init_rwsem().
5817          */
5818         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5819         lockdep_set_subclass(&ei->i_data_sem, subclass);
5820 }
5821
5822 /*
5823  * Standard function to be called on quota_on
5824  */
5825 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5826                          const struct path *path)
5827 {
5828         int err;
5829
5830         if (!test_opt(sb, QUOTA))
5831                 return -EINVAL;
5832
5833         /* Quotafile not on the same filesystem? */
5834         if (path->dentry->d_sb != sb)
5835                 return -EXDEV;
5836         /* Journaling quota? */
5837         if (EXT4_SB(sb)->s_qf_names[type]) {
5838                 /* Quotafile not in fs root? */
5839                 if (path->dentry->d_parent != sb->s_root)
5840                         ext4_msg(sb, KERN_WARNING,
5841                                 "Quota file not on filesystem root. "
5842                                 "Journaled quota will not work");
5843                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5844         } else {
5845                 /*
5846                  * Clear the flag just in case mount options changed since
5847                  * last time.
5848                  */
5849                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5850         }
5851
5852         /*
5853          * When we journal data on quota file, we have to flush journal to see
5854          * all updates to the file when we bypass pagecache...
5855          */
5856         if (EXT4_SB(sb)->s_journal &&
5857             ext4_should_journal_data(d_inode(path->dentry))) {
5858                 /*
5859                  * We don't need to lock updates but journal_flush() could
5860                  * otherwise be livelocked...
5861                  */
5862                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5863                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5864                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5865                 if (err)
5866                         return err;
5867         }
5868
5869         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5870         err = dquot_quota_on(sb, type, format_id, path);
5871         if (err) {
5872                 lockdep_set_quota_inode(path->dentry->d_inode,
5873                                              I_DATA_SEM_NORMAL);
5874         } else {
5875                 struct inode *inode = d_inode(path->dentry);
5876                 handle_t *handle;
5877
5878                 /*
5879                  * Set inode flags to prevent userspace from messing with quota
5880                  * files. If this fails, we return success anyway since quotas
5881                  * are already enabled and this is not a hard failure.
5882                  */
5883                 inode_lock(inode);
5884                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5885                 if (IS_ERR(handle))
5886                         goto unlock_inode;
5887                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5888                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5889                                 S_NOATIME | S_IMMUTABLE);
5890                 ext4_mark_inode_dirty(handle, inode);
5891                 ext4_journal_stop(handle);
5892         unlock_inode:
5893                 inode_unlock(inode);
5894         }
5895         return err;
5896 }
5897
5898 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5899                              unsigned int flags)
5900 {
5901         int err;
5902         struct inode *qf_inode;
5903         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5904                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5905                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5906                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5907         };
5908
5909         BUG_ON(!ext4_has_feature_quota(sb));
5910
5911         if (!qf_inums[type])
5912                 return -EPERM;
5913
5914         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5915         if (IS_ERR(qf_inode)) {
5916                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5917                 return PTR_ERR(qf_inode);
5918         }
5919
5920         /* Don't account quota for quota files to avoid recursion */
5921         qf_inode->i_flags |= S_NOQUOTA;
5922         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5923         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
5924         if (err)
5925                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5926         iput(qf_inode);
5927
5928         return err;
5929 }
5930
5931 /* Enable usage tracking for all quota types. */
5932 static int ext4_enable_quotas(struct super_block *sb)
5933 {
5934         int type, err = 0;
5935         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5936                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5937                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5938                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5939         };
5940         bool quota_mopt[EXT4_MAXQUOTAS] = {
5941                 test_opt(sb, USRQUOTA),
5942                 test_opt(sb, GRPQUOTA),
5943                 test_opt(sb, PRJQUOTA),
5944         };
5945
5946         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5947         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5948                 if (qf_inums[type]) {
5949                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5950                                 DQUOT_USAGE_ENABLED |
5951                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5952                         if (err) {
5953                                 ext4_warning(sb,
5954                                         "Failed to enable quota tracking "
5955                                         "(type=%d, err=%d). Please run "
5956                                         "e2fsck to fix.", type, err);
5957                                 for (type--; type >= 0; type--)
5958                                         dquot_quota_off(sb, type);
5959
5960                                 return err;
5961                         }
5962                 }
5963         }
5964         return 0;
5965 }
5966
5967 static int ext4_quota_off(struct super_block *sb, int type)
5968 {
5969         struct inode *inode = sb_dqopt(sb)->files[type];
5970         handle_t *handle;
5971         int err;
5972
5973         /* Force all delayed allocation blocks to be allocated.
5974          * Caller already holds s_umount sem */
5975         if (test_opt(sb, DELALLOC))
5976                 sync_filesystem(sb);
5977
5978         if (!inode || !igrab(inode))
5979                 goto out;
5980
5981         err = dquot_quota_off(sb, type);
5982         if (err || ext4_has_feature_quota(sb))
5983                 goto out_put;
5984
5985         inode_lock(inode);
5986         /*
5987          * Update modification times of quota files when userspace can
5988          * start looking at them. If we fail, we return success anyway since
5989          * this is not a hard failure and quotas are already disabled.
5990          */
5991         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5992         if (IS_ERR(handle))
5993                 goto out_unlock;
5994         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5995         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5996         inode->i_mtime = inode->i_ctime = current_time(inode);
5997         ext4_mark_inode_dirty(handle, inode);
5998         ext4_journal_stop(handle);
5999 out_unlock:
6000         inode_unlock(inode);
6001 out_put:
6002         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6003         iput(inode);
6004         return err;
6005 out:
6006         return dquot_quota_off(sb, type);
6007 }
6008
6009 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6010  * acquiring the locks... As quota files are never truncated and quota code
6011  * itself serializes the operations (and no one else should touch the files)
6012  * we don't have to be afraid of races */
6013 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6014                                size_t len, loff_t off)
6015 {
6016         struct inode *inode = sb_dqopt(sb)->files[type];
6017         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6018         int offset = off & (sb->s_blocksize - 1);
6019         int tocopy;
6020         size_t toread;
6021         struct buffer_head *bh;
6022         loff_t i_size = i_size_read(inode);
6023
6024         if (off > i_size)
6025                 return 0;
6026         if (off+len > i_size)
6027                 len = i_size-off;
6028         toread = len;
6029         while (toread > 0) {
6030                 tocopy = sb->s_blocksize - offset < toread ?
6031                                 sb->s_blocksize - offset : toread;
6032                 bh = ext4_bread(NULL, inode, blk, 0);
6033                 if (IS_ERR(bh))
6034                         return PTR_ERR(bh);
6035                 if (!bh)        /* A hole? */
6036                         memset(data, 0, tocopy);
6037                 else
6038                         memcpy(data, bh->b_data+offset, tocopy);
6039                 brelse(bh);
6040                 offset = 0;
6041                 toread -= tocopy;
6042                 data += tocopy;
6043                 blk++;
6044         }
6045         return len;
6046 }
6047
6048 /* Write to quotafile (we know the transaction is already started and has
6049  * enough credits) */
6050 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6051                                 const char *data, size_t len, loff_t off)
6052 {
6053         struct inode *inode = sb_dqopt(sb)->files[type];
6054         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6055         int err, offset = off & (sb->s_blocksize - 1);
6056         int retries = 0;
6057         struct buffer_head *bh;
6058         handle_t *handle = journal_current_handle();
6059
6060         if (EXT4_SB(sb)->s_journal && !handle) {
6061                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6062                         " cancelled because transaction is not started",
6063                         (unsigned long long)off, (unsigned long long)len);
6064                 return -EIO;
6065         }
6066         /*
6067          * Since we account only one data block in transaction credits,
6068          * then it is impossible to cross a block boundary.
6069          */
6070         if (sb->s_blocksize - offset < len) {
6071                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6072                         " cancelled because not block aligned",
6073                         (unsigned long long)off, (unsigned long long)len);
6074                 return -EIO;
6075         }
6076
6077         do {
6078                 bh = ext4_bread(handle, inode, blk,
6079                                 EXT4_GET_BLOCKS_CREATE |
6080                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6081         } while (PTR_ERR(bh) == -ENOSPC &&
6082                  ext4_should_retry_alloc(inode->i_sb, &retries));
6083         if (IS_ERR(bh))
6084                 return PTR_ERR(bh);
6085         if (!bh)
6086                 goto out;
6087         BUFFER_TRACE(bh, "get write access");
6088         err = ext4_journal_get_write_access(handle, bh);
6089         if (err) {
6090                 brelse(bh);
6091                 return err;
6092         }
6093         lock_buffer(bh);
6094         memcpy(bh->b_data+offset, data, len);
6095         flush_dcache_page(bh->b_page);
6096         unlock_buffer(bh);
6097         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6098         brelse(bh);
6099 out:
6100         if (inode->i_size < off + len) {
6101                 i_size_write(inode, off + len);
6102                 EXT4_I(inode)->i_disksize = inode->i_size;
6103                 ext4_mark_inode_dirty(handle, inode);
6104         }
6105         return len;
6106 }
6107 #endif
6108
6109 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6110                        const char *dev_name, void *data)
6111 {
6112         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6113 }
6114
6115 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6116 static inline void register_as_ext2(void)
6117 {
6118         int err = register_filesystem(&ext2_fs_type);
6119         if (err)
6120                 printk(KERN_WARNING
6121                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6122 }
6123
6124 static inline void unregister_as_ext2(void)
6125 {
6126         unregister_filesystem(&ext2_fs_type);
6127 }
6128
6129 static inline int ext2_feature_set_ok(struct super_block *sb)
6130 {
6131         if (ext4_has_unknown_ext2_incompat_features(sb))
6132                 return 0;
6133         if (sb_rdonly(sb))
6134                 return 1;
6135         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6136                 return 0;
6137         return 1;
6138 }
6139 #else
6140 static inline void register_as_ext2(void) { }
6141 static inline void unregister_as_ext2(void) { }
6142 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6143 #endif
6144
6145 static inline void register_as_ext3(void)
6146 {
6147         int err = register_filesystem(&ext3_fs_type);
6148         if (err)
6149                 printk(KERN_WARNING
6150                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6151 }
6152
6153 static inline void unregister_as_ext3(void)
6154 {
6155         unregister_filesystem(&ext3_fs_type);
6156 }
6157
6158 static inline int ext3_feature_set_ok(struct super_block *sb)
6159 {
6160         if (ext4_has_unknown_ext3_incompat_features(sb))
6161                 return 0;
6162         if (!ext4_has_feature_journal(sb))
6163                 return 0;
6164         if (sb_rdonly(sb))
6165                 return 1;
6166         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6167                 return 0;
6168         return 1;
6169 }
6170
6171 static struct file_system_type ext4_fs_type = {
6172         .owner          = THIS_MODULE,
6173         .name           = "ext4",
6174         .mount          = ext4_mount,
6175         .kill_sb        = kill_block_super,
6176         .fs_flags       = FS_REQUIRES_DEV,
6177 };
6178 MODULE_ALIAS_FS("ext4");
6179
6180 /* Shared across all ext4 file systems */
6181 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6182
6183 static int __init ext4_init_fs(void)
6184 {
6185         int i, err;
6186
6187         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6188         ext4_li_info = NULL;
6189         mutex_init(&ext4_li_mtx);
6190
6191         /* Build-time check for flags consistency */
6192         ext4_check_flag_values();
6193
6194         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6195                 init_waitqueue_head(&ext4__ioend_wq[i]);
6196
6197         err = ext4_init_es();
6198         if (err)
6199                 return err;
6200
6201         err = ext4_init_pending();
6202         if (err)
6203                 goto out7;
6204
6205         err = ext4_init_post_read_processing();
6206         if (err)
6207                 goto out6;
6208
6209         err = ext4_init_pageio();
6210         if (err)
6211                 goto out5;
6212
6213         err = ext4_init_system_zone();
6214         if (err)
6215                 goto out4;
6216
6217         err = ext4_init_sysfs();
6218         if (err)
6219                 goto out3;
6220
6221         err = ext4_init_mballoc();
6222         if (err)
6223                 goto out2;
6224         err = init_inodecache();
6225         if (err)
6226                 goto out1;
6227         register_as_ext3();
6228         register_as_ext2();
6229         err = register_filesystem(&ext4_fs_type);
6230         if (err)
6231                 goto out;
6232
6233         return 0;
6234 out:
6235         unregister_as_ext2();
6236         unregister_as_ext3();
6237         destroy_inodecache();
6238 out1:
6239         ext4_exit_mballoc();
6240 out2:
6241         ext4_exit_sysfs();
6242 out3:
6243         ext4_exit_system_zone();
6244 out4:
6245         ext4_exit_pageio();
6246 out5:
6247         ext4_exit_post_read_processing();
6248 out6:
6249         ext4_exit_pending();
6250 out7:
6251         ext4_exit_es();
6252
6253         return err;
6254 }
6255
6256 static void __exit ext4_exit_fs(void)
6257 {
6258         ext4_destroy_lazyinit_thread();
6259         unregister_as_ext2();
6260         unregister_as_ext3();
6261         unregister_filesystem(&ext4_fs_type);
6262         destroy_inodecache();
6263         ext4_exit_mballoc();
6264         ext4_exit_sysfs();
6265         ext4_exit_system_zone();
6266         ext4_exit_pageio();
6267         ext4_exit_post_read_processing();
6268         ext4_exit_es();
6269         ext4_exit_pending();
6270 }
6271
6272 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6273 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6274 MODULE_LICENSE("GPL");
6275 MODULE_SOFTDEP("pre: crc32c");
6276 module_init(ext4_init_fs)
6277 module_exit(ext4_exit_fs)