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 int ext4_mark_recovery_complete(struct super_block *sb,
  70                                         struct ext4_super_block *es);
  71 static int 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_lock -> 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_lock
 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_lock
 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 static inline void __ext4_read_bh(struct buffer_head *bh, int op_flags,
 146                                   bh_end_io_t *end_io)
 147 {
 148         /*
 149          * buffer's verified bit is no longer valid after reading from
 150          * disk again due to write out error, clear it to make sure we
 151          * recheck the buffer contents.
 152          */
 153         clear_buffer_verified(bh);
 154
 155         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
 156         get_bh(bh);
 157         submit_bh(REQ_OP_READ, op_flags, bh);
 158 }
 159
 160 void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
 161                          bh_end_io_t *end_io)
 162 {
 163         BUG_ON(!buffer_locked(bh));
 164
 165         if (ext4_buffer_uptodate(bh)) {
 166                 unlock_buffer(bh);
 167                 return;
 168         }
 169         __ext4_read_bh(bh, op_flags, end_io);
 170 }
 171
 172 int ext4_read_bh(struct buffer_head *bh, int op_flags, bh_end_io_t *end_io)
 173 {
 174         BUG_ON(!buffer_locked(bh));
 175
 176         if (ext4_buffer_uptodate(bh)) {
 177                 unlock_buffer(bh);
 178                 return 0;
 179         }
 180
 181         __ext4_read_bh(bh, op_flags, end_io);
 182
 183         wait_on_buffer(bh);
 184         if (buffer_uptodate(bh))
 185                 return 0;
 186         return -EIO;
 187 }
 188
 189 int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait)
 190 {
 191         if (trylock_buffer(bh)) {
 192                 if (wait)
 193                         return ext4_read_bh(bh, op_flags, NULL);
 194                 ext4_read_bh_nowait(bh, op_flags, NULL);
 195                 return 0;
 196         }
 197         if (wait) {
 198                 wait_on_buffer(bh);
 199                 if (buffer_uptodate(bh))
 200                         return 0;
 201                 return -EIO;
 202         }
 203         return 0;
 204 }
 205
 206 /*
 207  * This works like __bread_gfp() except it uses ERR_PTR for error
 208  * returns.  Currently with sb_bread it's impossible to distinguish
 209  * between ENOMEM and EIO situations (since both result in a NULL
 210  * return.
 211  */
 212 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 213                                                sector_t block, int op_flags,
 214                                                gfp_t gfp)
 215 {
 216         struct buffer_head *bh;
 217         int ret;
 218
 219         bh = sb_getblk_gfp(sb, block, gfp);
 220         if (bh == NULL)
 221                 return ERR_PTR(-ENOMEM);
 222         if (ext4_buffer_uptodate(bh))
 223                 return bh;
 224
 225         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
 226         if (ret) {
 227                 put_bh(bh);
 228                 return ERR_PTR(ret);
 229         }
 230         return bh;
 231 }
 232
 233 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 234                                    int op_flags)
 235 {
 236         return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
 237 }
 238
 239 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 240                                             sector_t block)
 241 {
 242         return __ext4_sb_bread_gfp(sb, block, 0, 0);
 243 }
 244
 245 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
 246 {
 247         struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
 248
 249         if (likely(bh)) {
 250                 ext4_read_bh_lock(bh, REQ_RAHEAD, false);
 251                 brelse(bh);
 252         }
 253 }
 254
 255 static int ext4_verify_csum_type(struct super_block *sb,
 256                                  struct ext4_super_block *es)
 257 {
 258         if (!ext4_has_feature_metadata_csum(sb))
 259                 return 1;
 260
 261         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 262 }
 263
 264 static __le32 ext4_superblock_csum(struct super_block *sb,
 265                                    struct ext4_super_block *es)
 266 {
 267         struct ext4_sb_info *sbi = EXT4_SB(sb);
 268         int offset = offsetof(struct ext4_super_block, s_checksum);
 269         __u32 csum;
 270
 271         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 272
 273         return cpu_to_le32(csum);
 274 }
 275
 276 static int ext4_superblock_csum_verify(struct super_block *sb,
 277                                        struct ext4_super_block *es)
 278 {
 279         if (!ext4_has_metadata_csum(sb))
 280                 return 1;
 281
 282         return es->s_checksum == ext4_superblock_csum(sb, es);
 283 }
 284
 285 void ext4_superblock_csum_set(struct super_block *sb)
 286 {
 287         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 288
 289         if (!ext4_has_metadata_csum(sb))
 290                 return;
 291
 292         es->s_checksum = ext4_superblock_csum(sb, es);
 293 }
 294
 295 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 296                                struct ext4_group_desc *bg)
 297 {
 298         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 299                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 300                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 301 }
 302
 303 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 304                                struct ext4_group_desc *bg)
 305 {
 306         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 307                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 308                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 309 }
 310
 311 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 312                               struct ext4_group_desc *bg)
 313 {
 314         return le32_to_cpu(bg->bg_inode_table_lo) |
 315                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 316                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 317 }
 318
 319 __u32 ext4_free_group_clusters(struct super_block *sb,
 320                                struct ext4_group_desc *bg)
 321 {
 322         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 323                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 324                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 325 }
 326
 327 __u32 ext4_free_inodes_count(struct super_block *sb,
 328                               struct ext4_group_desc *bg)
 329 {
 330         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 331                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 332                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 333 }
 334
 335 __u32 ext4_used_dirs_count(struct super_block *sb,
 336                               struct ext4_group_desc *bg)
 337 {
 338         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 339                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 340                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 341 }
 342
 343 __u32 ext4_itable_unused_count(struct super_block *sb,
 344                               struct ext4_group_desc *bg)
 345 {
 346         return le16_to_cpu(bg->bg_itable_unused_lo) |
 347                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 348                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 349 }
 350
 351 void ext4_block_bitmap_set(struct super_block *sb,
 352                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 353 {
 354         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 355         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 356                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 357 }
 358
 359 void ext4_inode_bitmap_set(struct super_block *sb,
 360                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 361 {
 362         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 363         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 364                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 365 }
 366
 367 void ext4_inode_table_set(struct super_block *sb,
 368                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 369 {
 370         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 371         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 372                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 373 }
 374
 375 void ext4_free_group_clusters_set(struct super_block *sb,
 376                                   struct ext4_group_desc *bg, __u32 count)
 377 {
 378         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 379         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 380                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 381 }
 382
 383 void ext4_free_inodes_set(struct super_block *sb,
 384                           struct ext4_group_desc *bg, __u32 count)
 385 {
 386         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 387         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 388                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 389 }
 390
 391 void ext4_used_dirs_set(struct super_block *sb,
 392                           struct ext4_group_desc *bg, __u32 count)
 393 {
 394         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 395         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 396                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 397 }
 398
 399 void ext4_itable_unused_set(struct super_block *sb,
 400                           struct ext4_group_desc *bg, __u32 count)
 401 {
 402         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 403         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 404                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 405 }
 406
 407 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
 408 {
 409         time64_t now = ktime_get_real_seconds();
 410
 411         now = clamp_val(now, 0, (1ull << 40) - 1);
 412
 413         *lo = cpu_to_le32(lower_32_bits(now));
 414         *hi = upper_32_bits(now);
 415 }
 416
 417 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 418 {
 419         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 420 }
 421 #define ext4_update_tstamp(es, tstamp) \
 422         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 423 #define ext4_get_tstamp(es, tstamp) \
 424         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 425
 426 static void __save_error_info(struct super_block *sb, int error,
 427                               __u32 ino, __u64 block,
 428                               const char *func, unsigned int line)
 429 {
 430         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 431         int err;
 432
 433         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 434         if (bdev_read_only(sb->s_bdev))
 435                 return;
 436         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 437         ext4_update_tstamp(es, s_last_error_time);
 438         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 439         es->s_last_error_line = cpu_to_le32(line);
 440         es->s_last_error_ino = cpu_to_le32(ino);
 441         es->s_last_error_block = cpu_to_le64(block);
 442         switch (error) {
 443         case EIO:
 444                 err = EXT4_ERR_EIO;
 445                 break;
 446         case ENOMEM:
 447                 err = EXT4_ERR_ENOMEM;
 448                 break;
 449         case EFSBADCRC:
 450                 err = EXT4_ERR_EFSBADCRC;
 451                 break;
 452         case 0:
 453         case EFSCORRUPTED:
 454                 err = EXT4_ERR_EFSCORRUPTED;
 455                 break;
 456         case ENOSPC:
 457                 err = EXT4_ERR_ENOSPC;
 458                 break;
 459         case ENOKEY:
 460                 err = EXT4_ERR_ENOKEY;
 461                 break;
 462         case EROFS:
 463                 err = EXT4_ERR_EROFS;
 464                 break;
 465         case EFBIG:
 466                 err = EXT4_ERR_EFBIG;
 467                 break;
 468         case EEXIST:
 469                 err = EXT4_ERR_EEXIST;
 470                 break;
 471         case ERANGE:
 472                 err = EXT4_ERR_ERANGE;
 473                 break;
 474         case EOVERFLOW:
 475                 err = EXT4_ERR_EOVERFLOW;
 476                 break;
 477         case EBUSY:
 478                 err = EXT4_ERR_EBUSY;
 479                 break;
 480         case ENOTDIR:
 481                 err = EXT4_ERR_ENOTDIR;
 482                 break;
 483         case ENOTEMPTY:
 484                 err = EXT4_ERR_ENOTEMPTY;
 485                 break;
 486         case ESHUTDOWN:
 487                 err = EXT4_ERR_ESHUTDOWN;
 488                 break;
 489         case EFAULT:
 490                 err = EXT4_ERR_EFAULT;
 491                 break;
 492         default:
 493                 err = EXT4_ERR_UNKNOWN;
 494         }
 495         es->s_last_error_errcode = err;
 496         if (!es->s_first_error_time) {
 497                 es->s_first_error_time = es->s_last_error_time;
 498                 es->s_first_error_time_hi = es->s_last_error_time_hi;
 499                 strncpy(es->s_first_error_func, func,
 500                         sizeof(es->s_first_error_func));
 501                 es->s_first_error_line = cpu_to_le32(line);
 502                 es->s_first_error_ino = es->s_last_error_ino;
 503                 es->s_first_error_block = es->s_last_error_block;
 504                 es->s_first_error_errcode = es->s_last_error_errcode;
 505         }
 506         /*
 507          * Start the daily error reporting function if it hasn't been
 508          * started already
 509          */
 510         if (!es->s_error_count)
 511                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 512         le32_add_cpu(&es->s_error_count, 1);
 513 }
 514
 515 static void save_error_info(struct super_block *sb, int error,
 516                             __u32 ino, __u64 block,
 517                             const char *func, unsigned int line)
 518 {
 519         __save_error_info(sb, error, ino, block, func, line);
 520         if (!bdev_read_only(sb->s_bdev))
 521                 ext4_commit_super(sb, 1);
 522 }
 523
 524 /*
 525  * The del_gendisk() function uninitializes the disk-specific data
 526  * structures, including the bdi structure, without telling anyone
 527  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 528  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 529  * This is a kludge to prevent these oops until we can put in a proper
 530  * hook in del_gendisk() to inform the VFS and file system layers.
 531  */
 532 static int block_device_ejected(struct super_block *sb)
 533 {
 534         struct inode *bd_inode = sb->s_bdev->bd_inode;
 535         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 536
 537         return bdi->dev == NULL;
 538 }
 539
 540 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 541 {
 542         struct super_block              *sb = journal->j_private;
 543         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 544         int                             error = is_journal_aborted(journal);
 545         struct ext4_journal_cb_entry    *jce;
 546
 547         BUG_ON(txn->t_state == T_FINISHED);
 548
 549         ext4_process_freed_data(sb, txn->t_tid);
 550
 551         spin_lock(&sbi->s_md_lock);
 552         while (!list_empty(&txn->t_private_list)) {
 553                 jce = list_entry(txn->t_private_list.next,
 554                                  struct ext4_journal_cb_entry, jce_list);
 555                 list_del_init(&jce->jce_list);
 556                 spin_unlock(&sbi->s_md_lock);
 557                 jce->jce_func(sb, jce, error);
 558                 spin_lock(&sbi->s_md_lock);
 559         }
 560         spin_unlock(&sbi->s_md_lock);
 561 }
 562
 563 /*
 564  * This writepage callback for write_cache_pages()
 565  * takes care of a few cases after page cleaning.
 566  *
 567  * write_cache_pages() already checks for dirty pages
 568  * and calls clear_page_dirty_for_io(), which we want,
 569  * to write protect the pages.
 570  *
 571  * However, we may have to redirty a page (see below.)
 572  */
 573 static int ext4_journalled_writepage_callback(struct page *page,
 574                                               struct writeback_control *wbc,
 575                                               void *data)
 576 {
 577         transaction_t *transaction = (transaction_t *) data;
 578         struct buffer_head *bh, *head;
 579         struct journal_head *jh;
 580
 581         bh = head = page_buffers(page);
 582         do {
 583                 /*
 584                  * We have to redirty a page in these cases:
 585                  * 1) If buffer is dirty, it means the page was dirty because it
 586                  * contains a buffer that needs checkpointing. So the dirty bit
 587                  * needs to be preserved so that checkpointing writes the buffer
 588                  * properly.
 589                  * 2) If buffer is not part of the committing transaction
 590                  * (we may have just accidentally come across this buffer because
 591                  * inode range tracking is not exact) or if the currently running
 592                  * transaction already contains this buffer as well, dirty bit
 593                  * needs to be preserved so that the buffer gets writeprotected
 594                  * properly on running transaction's commit.
 595                  */
 596                 jh = bh2jh(bh);
 597                 if (buffer_dirty(bh) ||
 598                     (jh && (jh->b_transaction != transaction ||
 599                             jh->b_next_transaction))) {
 600                         redirty_page_for_writepage(wbc, page);
 601                         goto out;
 602                 }
 603         } while ((bh = bh->b_this_page) != head);
 604
 605 out:
 606         return AOP_WRITEPAGE_ACTIVATE;
 607 }
 608
 609 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
 610 {
 611         struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
 612         struct writeback_control wbc = {
 613                 .sync_mode =  WB_SYNC_ALL,
 614                 .nr_to_write = LONG_MAX,
 615                 .range_start = jinode->i_dirty_start,
 616                 .range_end = jinode->i_dirty_end,
 617         };
 618
 619         return write_cache_pages(mapping, &wbc,
 620                                  ext4_journalled_writepage_callback,
 621                                  jinode->i_transaction);
 622 }
 623
 624 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
 625 {
 626         int ret;
 627
 628         if (ext4_should_journal_data(jinode->i_vfs_inode))
 629                 ret = ext4_journalled_submit_inode_data_buffers(jinode);
 630         else
 631                 ret = jbd2_journal_submit_inode_data_buffers(jinode);
 632
 633         return ret;
 634 }
 635
 636 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
 637 {
 638         int ret = 0;
 639
 640         if (!ext4_should_journal_data(jinode->i_vfs_inode))
 641                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
 642
 643         return ret;
 644 }
 645
 646 static bool system_going_down(void)
 647 {
 648         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 649                 || system_state == SYSTEM_RESTART;
 650 }
 651
 652 /* Deal with the reporting of failure conditions on a filesystem such as
 653  * inconsistencies detected or read IO failures.
 654  *
 655  * On ext2, we can store the error state of the filesystem in the
 656  * superblock.  That is not possible on ext4, because we may have other
 657  * write ordering constraints on the superblock which prevent us from
 658  * writing it out straight away; and given that the journal is about to
 659  * be aborted, we can't rely on the current, or future, transactions to
 660  * write out the superblock safely.
 661  *
 662  * We'll just use the jbd2_journal_abort() error code to record an error in
 663  * the journal instead.  On recovery, the journal will complain about
 664  * that error until we've noted it down and cleared it.
 665  */
 666
 667 static void ext4_handle_error(struct super_block *sb)
 668 {
 669         if (test_opt(sb, WARN_ON_ERROR))
 670                 WARN_ON_ONCE(1);
 671
 672         if (sb_rdonly(sb))
 673                 return;
 674
 675         if (!test_opt(sb, ERRORS_CONT)) {
 676                 journal_t *journal = EXT4_SB(sb)->s_journal;
 677
 678                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
 679                 if (journal)
 680                         jbd2_journal_abort(journal, -EIO);
 681         }
 682         /*
 683          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 684          * could panic during 'reboot -f' as the underlying device got already
 685          * disabled.
 686          */
 687         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
 688                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 689                 /*
 690                  * Make sure updated value of ->s_mount_flags will be visible
 691                  * before ->s_flags update
 692                  */
 693                 smp_wmb();
 694                 sb->s_flags |= SB_RDONLY;
 695         } else if (test_opt(sb, ERRORS_PANIC)) {
 696                 panic("EXT4-fs (device %s): panic forced after error\n",
 697                         sb->s_id);
 698         }
 699 }
 700
 701 #define ext4_error_ratelimit(sb)                                        \
 702                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 703                              "EXT4-fs error")
 704
 705 void __ext4_error(struct super_block *sb, const char *function,
 706                   unsigned int line, int error, __u64 block,
 707                   const char *fmt, ...)
 708 {
 709         struct va_format vaf;
 710         va_list args;
 711
 712         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 713                 return;
 714
 715         trace_ext4_error(sb, function, line);
 716         if (ext4_error_ratelimit(sb)) {
 717                 va_start(args, fmt);
 718                 vaf.fmt = fmt;
 719                 vaf.va = &args;
 720                 printk(KERN_CRIT
 721                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 722                        sb->s_id, function, line, current->comm, &vaf);
 723                 va_end(args);
 724         }
 725         save_error_info(sb, error, 0, block, function, line);
 726         ext4_handle_error(sb);
 727 }
 728
 729 void __ext4_error_inode(struct inode *inode, const char *function,
 730                         unsigned int line, ext4_fsblk_t block, int error,
 731                         const char *fmt, ...)
 732 {
 733         va_list args;
 734         struct va_format vaf;
 735
 736         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 737                 return;
 738
 739         trace_ext4_error(inode->i_sb, function, line);
 740         if (ext4_error_ratelimit(inode->i_sb)) {
 741                 va_start(args, fmt);
 742                 vaf.fmt = fmt;
 743                 vaf.va = &args;
 744                 if (block)
 745                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 746                                "inode #%lu: block %llu: comm %s: %pV\n",
 747                                inode->i_sb->s_id, function, line, inode->i_ino,
 748                                block, current->comm, &vaf);
 749                 else
 750                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 751                                "inode #%lu: comm %s: %pV\n",
 752                                inode->i_sb->s_id, function, line, inode->i_ino,
 753                                current->comm, &vaf);
 754                 va_end(args);
 755         }
 756         save_error_info(inode->i_sb, error, inode->i_ino, block,
 757                         function, line);
 758         ext4_handle_error(inode->i_sb);
 759 }
 760
 761 void __ext4_error_file(struct file *file, const char *function,
 762                        unsigned int line, ext4_fsblk_t block,
 763                        const char *fmt, ...)
 764 {
 765         va_list args;
 766         struct va_format vaf;
 767         struct inode *inode = file_inode(file);
 768         char pathname[80], *path;
 769
 770         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 771                 return;
 772
 773         trace_ext4_error(inode->i_sb, function, line);
 774         if (ext4_error_ratelimit(inode->i_sb)) {
 775                 path = file_path(file, pathname, sizeof(pathname));
 776                 if (IS_ERR(path))
 777                         path = "(unknown)";
 778                 va_start(args, fmt);
 779                 vaf.fmt = fmt;
 780                 vaf.va = &args;
 781                 if (block)
 782                         printk(KERN_CRIT
 783                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 784                                "block %llu: comm %s: path %s: %pV\n",
 785                                inode->i_sb->s_id, function, line, inode->i_ino,
 786                                block, current->comm, path, &vaf);
 787                 else
 788                         printk(KERN_CRIT
 789                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 790                                "comm %s: path %s: %pV\n",
 791                                inode->i_sb->s_id, function, line, inode->i_ino,
 792                                current->comm, path, &vaf);
 793                 va_end(args);
 794         }
 795         save_error_info(inode->i_sb, EFSCORRUPTED, inode->i_ino, block,
 796                         function, line);
 797         ext4_handle_error(inode->i_sb);
 798 }
 799
 800 const char *ext4_decode_error(struct super_block *sb, int errno,
 801                               char nbuf[16])
 802 {
 803         char *errstr = NULL;
 804
 805         switch (errno) {
 806         case -EFSCORRUPTED:
 807                 errstr = "Corrupt filesystem";
 808                 break;
 809         case -EFSBADCRC:
 810                 errstr = "Filesystem failed CRC";
 811                 break;
 812         case -EIO:
 813                 errstr = "IO failure";
 814                 break;
 815         case -ENOMEM:
 816                 errstr = "Out of memory";
 817                 break;
 818         case -EROFS:
 819                 if (!sb || (EXT4_SB(sb)->s_journal &&
 820                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 821                         errstr = "Journal has aborted";
 822                 else
 823                         errstr = "Readonly filesystem";
 824                 break;
 825         default:
 826                 /* If the caller passed in an extra buffer for unknown
 827                  * errors, textualise them now.  Else we just return
 828                  * NULL. */
 829                 if (nbuf) {
 830                         /* Check for truncated error codes... */
 831                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 832                                 errstr = nbuf;
 833                 }
 834                 break;
 835         }
 836
 837         return errstr;
 838 }
 839
 840 /* __ext4_std_error decodes expected errors from journaling functions
 841  * automatically and invokes the appropriate error response.  */
 842
 843 void __ext4_std_error(struct super_block *sb, const char *function,
 844                       unsigned int line, int errno)
 845 {
 846         char nbuf[16];
 847         const char *errstr;
 848
 849         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 850                 return;
 851
 852         /* Special case: if the error is EROFS, and we're not already
 853          * inside a transaction, then there's really no point in logging
 854          * an error. */
 855         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 856                 return;
 857
 858         if (ext4_error_ratelimit(sb)) {
 859                 errstr = ext4_decode_error(sb, errno, nbuf);
 860                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 861                        sb->s_id, function, line, errstr);
 862         }
 863
 864         save_error_info(sb, -errno, 0, 0, function, line);
 865         ext4_handle_error(sb);
 866 }
 867
 868 /*
 869  * ext4_abort is a much stronger failure handler than ext4_error.  The
 870  * abort function may be used to deal with unrecoverable failures such
 871  * as journal IO errors or ENOMEM at a critical moment in log management.
 872  *
 873  * We unconditionally force the filesystem into an ABORT|READONLY state,
 874  * unless the error response on the fs has been set to panic in which
 875  * case we take the easy way out and panic immediately.
 876  */
 877
 878 void __ext4_abort(struct super_block *sb, const char *function,
 879                   unsigned int line, int error, const char *fmt, ...)
 880 {
 881         struct va_format vaf;
 882         va_list args;
 883
 884         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 885                 return;
 886
 887         save_error_info(sb, error, 0, 0, function, line);
 888         va_start(args, fmt);
 889         vaf.fmt = fmt;
 890         vaf.va = &args;
 891         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 892                sb->s_id, function, line, &vaf);
 893         va_end(args);
 894
 895         if (sb_rdonly(sb) == 0) {
 896                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
 897                 if (EXT4_SB(sb)->s_journal)
 898                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 899
 900                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 901                 /*
 902                  * Make sure updated value of ->s_mount_flags will be visible
 903                  * before ->s_flags update
 904                  */
 905                 smp_wmb();
 906                 sb->s_flags |= SB_RDONLY;
 907         }
 908         if (test_opt(sb, ERRORS_PANIC) && !system_going_down())
 909                 panic("EXT4-fs panic from previous error\n");
 910 }
 911
 912 void __ext4_msg(struct super_block *sb,
 913                 const char *prefix, const char *fmt, ...)
 914 {
 915         struct va_format vaf;
 916         va_list args;
 917
 918         atomic_inc(&EXT4_SB(sb)->s_msg_count);
 919         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 920                 return;
 921
 922         va_start(args, fmt);
 923         vaf.fmt = fmt;
 924         vaf.va = &args;
 925         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 926         va_end(args);
 927 }
 928
 929 static int ext4_warning_ratelimit(struct super_block *sb)
 930 {
 931         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 932         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 933                             "EXT4-fs warning");
 934 }
 935
 936 void __ext4_warning(struct super_block *sb, const char *function,
 937                     unsigned int line, const char *fmt, ...)
 938 {
 939         struct va_format vaf;
 940         va_list args;
 941
 942         if (!ext4_warning_ratelimit(sb))
 943                 return;
 944
 945         va_start(args, fmt);
 946         vaf.fmt = fmt;
 947         vaf.va = &args;
 948         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 949                sb->s_id, function, line, &vaf);
 950         va_end(args);
 951 }
 952
 953 void __ext4_warning_inode(const struct inode *inode, const char *function,
 954                           unsigned int line, const char *fmt, ...)
 955 {
 956         struct va_format vaf;
 957         va_list args;
 958
 959         if (!ext4_warning_ratelimit(inode->i_sb))
 960                 return;
 961
 962         va_start(args, fmt);
 963         vaf.fmt = fmt;
 964         vaf.va = &args;
 965         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 966                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 967                function, line, inode->i_ino, current->comm, &vaf);
 968         va_end(args);
 969 }
 970
 971 void __ext4_grp_locked_error(const char *function, unsigned int line,
 972                              struct super_block *sb, ext4_group_t grp,
 973                              unsigned long ino, ext4_fsblk_t block,
 974                              const char *fmt, ...)
 975 __releases(bitlock)
 976 __acquires(bitlock)
 977 {
 978         struct va_format vaf;
 979         va_list args;
 980
 981         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 982                 return;
 983
 984         trace_ext4_error(sb, function, line);
 985         __save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
 986
 987         if (ext4_error_ratelimit(sb)) {
 988                 va_start(args, fmt);
 989                 vaf.fmt = fmt;
 990                 vaf.va = &args;
 991                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 992                        sb->s_id, function, line, grp);
 993                 if (ino)
 994                         printk(KERN_CONT "inode %lu: ", ino);
 995                 if (block)
 996                         printk(KERN_CONT "block %llu:",
 997                                (unsigned long long) block);
 998                 printk(KERN_CONT "%pV\n", &vaf);
 999                 va_end(args);
1000         }
1001
1002         if (test_opt(sb, WARN_ON_ERROR))
1003                 WARN_ON_ONCE(1);
1004
1005         if (test_opt(sb, ERRORS_CONT)) {
1006                 ext4_commit_super(sb, 0);
1007                 return;
1008         }
1009
1010         ext4_unlock_group(sb, grp);
1011         ext4_commit_super(sb, 1);
1012         ext4_handle_error(sb);
1013         /*
1014          * We only get here in the ERRORS_RO case; relocking the group
1015          * may be dangerous, but nothing bad will happen since the
1016          * filesystem will have already been marked read/only and the
1017          * journal has been aborted.  We return 1 as a hint to callers
1018          * who might what to use the return value from
1019          * ext4_grp_locked_error() to distinguish between the
1020          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1021          * aggressively from the ext4 function in question, with a
1022          * more appropriate error code.
1023          */
1024         ext4_lock_group(sb, grp);
1025         return;
1026 }
1027
1028 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1029                                      ext4_group_t group,
1030                                      unsigned int flags)
1031 {
1032         struct ext4_sb_info *sbi = EXT4_SB(sb);
1033         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1034         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1035         int ret;
1036
1037         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1038                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1039                                             &grp->bb_state);
1040                 if (!ret)
1041                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1042                                            grp->bb_free);
1043         }
1044
1045         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1046                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1047                                             &grp->bb_state);
1048                 if (!ret && gdp) {
1049                         int count;
1050
1051                         count = ext4_free_inodes_count(sb, gdp);
1052                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1053                                            count);
1054                 }
1055         }
1056 }
1057
1058 void ext4_update_dynamic_rev(struct super_block *sb)
1059 {
1060         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1061
1062         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1063                 return;
1064
1065         ext4_warning(sb,
1066                      "updating to rev %d because of new feature flag, "
1067                      "running e2fsck is recommended",
1068                      EXT4_DYNAMIC_REV);
1069
1070         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1071         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1072         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1073         /* leave es->s_feature_*compat flags alone */
1074         /* es->s_uuid will be set by e2fsck if empty */
1075
1076         /*
1077          * The rest of the superblock fields should be zero, and if not it
1078          * means they are likely already in use, so leave them alone.  We
1079          * can leave it up to e2fsck to clean up any inconsistencies there.
1080          */
1081 }
1082
1083 /*
1084  * Open the external journal device
1085  */
1086 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1087 {
1088         struct block_device *bdev;
1089
1090         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1091         if (IS_ERR(bdev))
1092                 goto fail;
1093         return bdev;
1094
1095 fail:
1096         ext4_msg(sb, KERN_ERR,
1097                  "failed to open journal device unknown-block(%u,%u) %ld",
1098                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1099         return NULL;
1100 }
1101
1102 /*
1103  * Release the journal device
1104  */
1105 static void ext4_blkdev_put(struct block_device *bdev)
1106 {
1107         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1108 }
1109
1110 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1111 {
1112         struct block_device *bdev;
1113         bdev = sbi->s_journal_bdev;
1114         if (bdev) {
1115                 ext4_blkdev_put(bdev);
1116                 sbi->s_journal_bdev = NULL;
1117         }
1118 }
1119
1120 static inline struct inode *orphan_list_entry(struct list_head *l)
1121 {
1122         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1123 }
1124
1125 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1126 {
1127         struct list_head *l;
1128
1129         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1130                  le32_to_cpu(sbi->s_es->s_last_orphan));
1131
1132         printk(KERN_ERR "sb_info orphan list:\n");
1133         list_for_each(l, &sbi->s_orphan) {
1134                 struct inode *inode = orphan_list_entry(l);
1135                 printk(KERN_ERR "  "
1136                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1137                        inode->i_sb->s_id, inode->i_ino, inode,
1138                        inode->i_mode, inode->i_nlink,
1139                        NEXT_ORPHAN(inode));
1140         }
1141 }
1142
1143 #ifdef CONFIG_QUOTA
1144 static int ext4_quota_off(struct super_block *sb, int type);
1145
1146 static inline void ext4_quota_off_umount(struct super_block *sb)
1147 {
1148         int type;
1149
1150         /* Use our quota_off function to clear inode flags etc. */
1151         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1152                 ext4_quota_off(sb, type);
1153 }
1154
1155 /*
1156  * This is a helper function which is used in the mount/remount
1157  * codepaths (which holds s_umount) to fetch the quota file name.
1158  */
1159 static inline char *get_qf_name(struct super_block *sb,
1160                                 struct ext4_sb_info *sbi,
1161                                 int type)
1162 {
1163         return rcu_dereference_protected(sbi->s_qf_names[type],
1164                                          lockdep_is_held(&sb->s_umount));
1165 }
1166 #else
1167 static inline void ext4_quota_off_umount(struct super_block *sb)
1168 {
1169 }
1170 #endif
1171
1172 static void ext4_put_super(struct super_block *sb)
1173 {
1174         struct ext4_sb_info *sbi = EXT4_SB(sb);
1175         struct ext4_super_block *es = sbi->s_es;
1176         struct buffer_head **group_desc;
1177         struct flex_groups **flex_groups;
1178         int aborted = 0;
1179         int i, err;
1180
1181         ext4_unregister_li_request(sb);
1182         ext4_quota_off_umount(sb);
1183
1184         destroy_workqueue(sbi->rsv_conversion_wq);
1185
1186         /*
1187          * Unregister sysfs before destroying jbd2 journal.
1188          * Since we could still access attr_journal_task attribute via sysfs
1189          * path which could have sbi->s_journal->j_task as NULL
1190          */
1191         ext4_unregister_sysfs(sb);
1192
1193         if (sbi->s_journal) {
1194                 aborted = is_journal_aborted(sbi->s_journal);
1195                 err = jbd2_journal_destroy(sbi->s_journal);
1196                 sbi->s_journal = NULL;
1197                 if ((err < 0) && !aborted) {
1198                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1199                 }
1200         }
1201
1202         ext4_es_unregister_shrinker(sbi);
1203         del_timer_sync(&sbi->s_err_report);
1204         ext4_release_system_zone(sb);
1205         ext4_mb_release(sb);
1206         ext4_ext_release(sb);
1207
1208         if (!sb_rdonly(sb) && !aborted) {
1209                 ext4_clear_feature_journal_needs_recovery(sb);
1210                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1211         }
1212         if (!sb_rdonly(sb))
1213                 ext4_commit_super(sb, 1);
1214
1215         rcu_read_lock();
1216         group_desc = rcu_dereference(sbi->s_group_desc);
1217         for (i = 0; i < sbi->s_gdb_count; i++)
1218                 brelse(group_desc[i]);
1219         kvfree(group_desc);
1220         flex_groups = rcu_dereference(sbi->s_flex_groups);
1221         if (flex_groups) {
1222                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1223                         kvfree(flex_groups[i]);
1224                 kvfree(flex_groups);
1225         }
1226         rcu_read_unlock();
1227         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1228         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1229         percpu_counter_destroy(&sbi->s_dirs_counter);
1230         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1231         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1232 #ifdef CONFIG_QUOTA
1233         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1234                 kfree(get_qf_name(sb, sbi, i));
1235 #endif
1236
1237         /* Debugging code just in case the in-memory inode orphan list
1238          * isn't empty.  The on-disk one can be non-empty if we've
1239          * detected an error and taken the fs readonly, but the
1240          * in-memory list had better be clean by this point. */
1241         if (!list_empty(&sbi->s_orphan))
1242                 dump_orphan_list(sb, sbi);
1243         ASSERT(list_empty(&sbi->s_orphan));
1244
1245         sync_blockdev(sb->s_bdev);
1246         invalidate_bdev(sb->s_bdev);
1247         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1248                 /*
1249                  * Invalidate the journal device's buffers.  We don't want them
1250                  * floating about in memory - the physical journal device may
1251                  * hotswapped, and it breaks the `ro-after' testing code.
1252                  */
1253                 sync_blockdev(sbi->s_journal_bdev);
1254                 invalidate_bdev(sbi->s_journal_bdev);
1255                 ext4_blkdev_remove(sbi);
1256         }
1257
1258         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1259         sbi->s_ea_inode_cache = NULL;
1260
1261         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1262         sbi->s_ea_block_cache = NULL;
1263
1264         if (sbi->s_mmp_tsk)
1265                 kthread_stop(sbi->s_mmp_tsk);
1266         brelse(sbi->s_sbh);
1267         sb->s_fs_info = NULL;
1268         /*
1269          * Now that we are completely done shutting down the
1270          * superblock, we need to actually destroy the kobject.
1271          */
1272         kobject_put(&sbi->s_kobj);
1273         wait_for_completion(&sbi->s_kobj_unregister);
1274         if (sbi->s_chksum_driver)
1275                 crypto_free_shash(sbi->s_chksum_driver);
1276         kfree(sbi->s_blockgroup_lock);
1277         fs_put_dax(sbi->s_daxdev);
1278         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1279 #ifdef CONFIG_UNICODE
1280         utf8_unload(sb->s_encoding);
1281 #endif
1282         kfree(sbi);
1283 }
1284
1285 static struct kmem_cache *ext4_inode_cachep;
1286
1287 /*
1288  * Called inside transaction, so use GFP_NOFS
1289  */
1290 static struct inode *ext4_alloc_inode(struct super_block *sb)
1291 {
1292         struct ext4_inode_info *ei;
1293
1294         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1295         if (!ei)
1296                 return NULL;
1297
1298         inode_set_iversion(&ei->vfs_inode, 1);
1299         spin_lock_init(&ei->i_raw_lock);
1300         INIT_LIST_HEAD(&ei->i_prealloc_list);
1301         atomic_set(&ei->i_prealloc_active, 0);
1302         spin_lock_init(&ei->i_prealloc_lock);
1303         ext4_es_init_tree(&ei->i_es_tree);
1304         rwlock_init(&ei->i_es_lock);
1305         INIT_LIST_HEAD(&ei->i_es_list);
1306         ei->i_es_all_nr = 0;
1307         ei->i_es_shk_nr = 0;
1308         ei->i_es_shrink_lblk = 0;
1309         ei->i_reserved_data_blocks = 0;
1310         spin_lock_init(&(ei->i_block_reservation_lock));
1311         ext4_init_pending_tree(&ei->i_pending_tree);
1312 #ifdef CONFIG_QUOTA
1313         ei->i_reserved_quota = 0;
1314         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1315 #endif
1316         ei->jinode = NULL;
1317         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1318         spin_lock_init(&ei->i_completed_io_lock);
1319         ei->i_sync_tid = 0;
1320         ei->i_datasync_tid = 0;
1321         atomic_set(&ei->i_unwritten, 0);
1322         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1323         ext4_fc_init_inode(&ei->vfs_inode);
1324         mutex_init(&ei->i_fc_lock);
1325         return &ei->vfs_inode;
1326 }
1327
1328 static int ext4_drop_inode(struct inode *inode)
1329 {
1330         int drop = generic_drop_inode(inode);
1331
1332         if (!drop)
1333                 drop = fscrypt_drop_inode(inode);
1334
1335         trace_ext4_drop_inode(inode, drop);
1336         return drop;
1337 }
1338
1339 static void ext4_free_in_core_inode(struct inode *inode)
1340 {
1341         fscrypt_free_inode(inode);
1342         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1343                 pr_warn("%s: inode %ld still in fc list",
1344                         __func__, inode->i_ino);
1345         }
1346         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1347 }
1348
1349 static void ext4_destroy_inode(struct inode *inode)
1350 {
1351         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1352                 ext4_msg(inode->i_sb, KERN_ERR,
1353                          "Inode %lu (%p): orphan list check failed!",
1354                          inode->i_ino, EXT4_I(inode));
1355                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1356                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1357                                 true);
1358                 dump_stack();
1359         }
1360 }
1361
1362 static void init_once(void *foo)
1363 {
1364         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1365
1366         INIT_LIST_HEAD(&ei->i_orphan);
1367         init_rwsem(&ei->xattr_sem);
1368         init_rwsem(&ei->i_data_sem);
1369         init_rwsem(&ei->i_mmap_sem);
1370         inode_init_once(&ei->vfs_inode);
1371         ext4_fc_init_inode(&ei->vfs_inode);
1372 }
1373
1374 static int __init init_inodecache(void)
1375 {
1376         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1377                                 sizeof(struct ext4_inode_info), 0,
1378                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1379                                         SLAB_ACCOUNT),
1380                                 offsetof(struct ext4_inode_info, i_data),
1381                                 sizeof_field(struct ext4_inode_info, i_data),
1382                                 init_once);
1383         if (ext4_inode_cachep == NULL)
1384                 return -ENOMEM;
1385         return 0;
1386 }
1387
1388 static void destroy_inodecache(void)
1389 {
1390         /*
1391          * Make sure all delayed rcu free inodes are flushed before we
1392          * destroy cache.
1393          */
1394         rcu_barrier();
1395         kmem_cache_destroy(ext4_inode_cachep);
1396 }
1397
1398 void ext4_clear_inode(struct inode *inode)
1399 {
1400         ext4_fc_del(inode);
1401         invalidate_inode_buffers(inode);
1402         clear_inode(inode);
1403         ext4_discard_preallocations(inode, 0);
1404         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1405         dquot_drop(inode);
1406         if (EXT4_I(inode)->jinode) {
1407                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1408                                                EXT4_I(inode)->jinode);
1409                 jbd2_free_inode(EXT4_I(inode)->jinode);
1410                 EXT4_I(inode)->jinode = NULL;
1411         }
1412         fscrypt_put_encryption_info(inode);
1413         fsverity_cleanup_inode(inode);
1414 }
1415
1416 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1417                                         u64 ino, u32 generation)
1418 {
1419         struct inode *inode;
1420
1421         /*
1422          * Currently we don't know the generation for parent directory, so
1423          * a generation of 0 means "accept any"
1424          */
1425         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1426         if (IS_ERR(inode))
1427                 return ERR_CAST(inode);
1428         if (generation && inode->i_generation != generation) {
1429                 iput(inode);
1430                 return ERR_PTR(-ESTALE);
1431         }
1432
1433         return inode;
1434 }
1435
1436 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1437                                         int fh_len, int fh_type)
1438 {
1439         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1440                                     ext4_nfs_get_inode);
1441 }
1442
1443 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1444                                         int fh_len, int fh_type)
1445 {
1446         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1447                                     ext4_nfs_get_inode);
1448 }
1449
1450 static int ext4_nfs_commit_metadata(struct inode *inode)
1451 {
1452         struct writeback_control wbc = {
1453                 .sync_mode = WB_SYNC_ALL
1454         };
1455
1456         trace_ext4_nfs_commit_metadata(inode);
1457         return ext4_write_inode(inode, &wbc);
1458 }
1459
1460 /*
1461  * Try to release metadata pages (indirect blocks, directories) which are
1462  * mapped via the block device.  Since these pages could have journal heads
1463  * which would prevent try_to_free_buffers() from freeing them, we must use
1464  * jbd2 layer's try_to_free_buffers() function to release them.
1465  */
1466 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1467                                  gfp_t wait)
1468 {
1469         journal_t *journal = EXT4_SB(sb)->s_journal;
1470
1471         WARN_ON(PageChecked(page));
1472         if (!page_has_buffers(page))
1473                 return 0;
1474         if (journal)
1475                 return jbd2_journal_try_to_free_buffers(journal, page);
1476
1477         return try_to_free_buffers(page);
1478 }
1479
1480 #ifdef CONFIG_FS_ENCRYPTION
1481 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1482 {
1483         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1484                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1485 }
1486
1487 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1488                                                         void *fs_data)
1489 {
1490         handle_t *handle = fs_data;
1491         int res, res2, credits, retries = 0;
1492
1493         /*
1494          * Encrypting the root directory is not allowed because e2fsck expects
1495          * lost+found to exist and be unencrypted, and encrypting the root
1496          * directory would imply encrypting the lost+found directory as well as
1497          * the filename "lost+found" itself.
1498          */
1499         if (inode->i_ino == EXT4_ROOT_INO)
1500                 return -EPERM;
1501
1502         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1503                 return -EINVAL;
1504
1505         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1506                 return -EOPNOTSUPP;
1507
1508         res = ext4_convert_inline_data(inode);
1509         if (res)
1510                 return res;
1511
1512         /*
1513          * If a journal handle was specified, then the encryption context is
1514          * being set on a new inode via inheritance and is part of a larger
1515          * transaction to create the inode.  Otherwise the encryption context is
1516          * being set on an existing inode in its own transaction.  Only in the
1517          * latter case should the "retry on ENOSPC" logic be used.
1518          */
1519
1520         if (handle) {
1521                 res = ext4_xattr_set_handle(handle, inode,
1522                                             EXT4_XATTR_INDEX_ENCRYPTION,
1523                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1524                                             ctx, len, 0);
1525                 if (!res) {
1526                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1527                         ext4_clear_inode_state(inode,
1528                                         EXT4_STATE_MAY_INLINE_DATA);
1529                         /*
1530                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1531                          * S_DAX may be disabled
1532                          */
1533                         ext4_set_inode_flags(inode, false);
1534                 }
1535                 return res;
1536         }
1537
1538         res = dquot_initialize(inode);
1539         if (res)
1540                 return res;
1541 retry:
1542         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1543                                      &credits);
1544         if (res)
1545                 return res;
1546
1547         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1548         if (IS_ERR(handle))
1549                 return PTR_ERR(handle);
1550
1551         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1552                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1553                                     ctx, len, 0);
1554         if (!res) {
1555                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1556                 /*
1557                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1558                  * S_DAX may be disabled
1559                  */
1560                 ext4_set_inode_flags(inode, false);
1561                 res = ext4_mark_inode_dirty(handle, inode);
1562                 if (res)
1563                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1564         }
1565         res2 = ext4_journal_stop(handle);
1566
1567         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1568                 goto retry;
1569         if (!res)
1570                 res = res2;
1571         return res;
1572 }
1573
1574 static const union fscrypt_policy *ext4_get_dummy_policy(struct super_block *sb)
1575 {
1576         return EXT4_SB(sb)->s_dummy_enc_policy.policy;
1577 }
1578
1579 static bool ext4_has_stable_inodes(struct super_block *sb)
1580 {
1581         return ext4_has_feature_stable_inodes(sb);
1582 }
1583
1584 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1585                                        int *ino_bits_ret, int *lblk_bits_ret)
1586 {
1587         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1588         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1589 }
1590
1591 static const struct fscrypt_operations ext4_cryptops = {
1592         .key_prefix             = "ext4:",
1593         .get_context            = ext4_get_context,
1594         .set_context            = ext4_set_context,
1595         .get_dummy_policy       = ext4_get_dummy_policy,
1596         .empty_dir              = ext4_empty_dir,
1597         .max_namelen            = EXT4_NAME_LEN,
1598         .has_stable_inodes      = ext4_has_stable_inodes,
1599         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1600 };
1601 #endif
1602
1603 #ifdef CONFIG_QUOTA
1604 static const char * const quotatypes[] = INITQFNAMES;
1605 #define QTYPE2NAME(t) (quotatypes[t])
1606
1607 static int ext4_write_dquot(struct dquot *dquot);
1608 static int ext4_acquire_dquot(struct dquot *dquot);
1609 static int ext4_release_dquot(struct dquot *dquot);
1610 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1611 static int ext4_write_info(struct super_block *sb, int type);
1612 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1613                          const struct path *path);
1614 static int ext4_quota_on_mount(struct super_block *sb, int type);
1615 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1616                                size_t len, loff_t off);
1617 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1618                                 const char *data, size_t len, loff_t off);
1619 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1620                              unsigned int flags);
1621 static int ext4_enable_quotas(struct super_block *sb);
1622
1623 static struct dquot **ext4_get_dquots(struct inode *inode)
1624 {
1625         return EXT4_I(inode)->i_dquot;
1626 }
1627
1628 static const struct dquot_operations ext4_quota_operations = {
1629         .get_reserved_space     = ext4_get_reserved_space,
1630         .write_dquot            = ext4_write_dquot,
1631         .acquire_dquot          = ext4_acquire_dquot,
1632         .release_dquot          = ext4_release_dquot,
1633         .mark_dirty             = ext4_mark_dquot_dirty,
1634         .write_info             = ext4_write_info,
1635         .alloc_dquot            = dquot_alloc,
1636         .destroy_dquot          = dquot_destroy,
1637         .get_projid             = ext4_get_projid,
1638         .get_inode_usage        = ext4_get_inode_usage,
1639         .get_next_id            = dquot_get_next_id,
1640 };
1641
1642 static const struct quotactl_ops ext4_qctl_operations = {
1643         .quota_on       = ext4_quota_on,
1644         .quota_off      = ext4_quota_off,
1645         .quota_sync     = dquot_quota_sync,
1646         .get_state      = dquot_get_state,
1647         .set_info       = dquot_set_dqinfo,
1648         .get_dqblk      = dquot_get_dqblk,
1649         .set_dqblk      = dquot_set_dqblk,
1650         .get_nextdqblk  = dquot_get_next_dqblk,
1651 };
1652 #endif
1653
1654 static const struct super_operations ext4_sops = {
1655         .alloc_inode    = ext4_alloc_inode,
1656         .free_inode     = ext4_free_in_core_inode,
1657         .destroy_inode  = ext4_destroy_inode,
1658         .write_inode    = ext4_write_inode,
1659         .dirty_inode    = ext4_dirty_inode,
1660         .drop_inode     = ext4_drop_inode,
1661         .evict_inode    = ext4_evict_inode,
1662         .put_super      = ext4_put_super,
1663         .sync_fs        = ext4_sync_fs,
1664         .freeze_fs      = ext4_freeze,
1665         .unfreeze_fs    = ext4_unfreeze,
1666         .statfs         = ext4_statfs,
1667         .remount_fs     = ext4_remount,
1668         .show_options   = ext4_show_options,
1669 #ifdef CONFIG_QUOTA
1670         .quota_read     = ext4_quota_read,
1671         .quota_write    = ext4_quota_write,
1672         .get_dquots     = ext4_get_dquots,
1673 #endif
1674         .bdev_try_to_free_page = bdev_try_to_free_page,
1675 };
1676
1677 static const struct export_operations ext4_export_ops = {
1678         .fh_to_dentry = ext4_fh_to_dentry,
1679         .fh_to_parent = ext4_fh_to_parent,
1680         .get_parent = ext4_get_parent,
1681         .commit_metadata = ext4_nfs_commit_metadata,
1682 };
1683
1684 enum {
1685         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1686         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1687         Opt_nouid32, Opt_debug, Opt_removed,
1688         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1689         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1690         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1691         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1692         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1693         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1694         Opt_inlinecrypt,
1695         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1696         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1697         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1698         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1699         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1700         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1701         Opt_nowarn_on_error, Opt_mblk_io_submit,
1702         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1703         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1704         Opt_inode_readahead_blks, Opt_journal_ioprio,
1705         Opt_dioread_nolock, Opt_dioread_lock,
1706         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1707         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1708         Opt_prefetch_block_bitmaps,
1709 #ifdef CONFIG_EXT4_DEBUG
1710         Opt_fc_debug_max_replay, Opt_fc_debug_force
1711 #endif
1712 };
1713
1714 static const match_table_t tokens = {
1715         {Opt_bsd_df, "bsddf"},
1716         {Opt_minix_df, "minixdf"},
1717         {Opt_grpid, "grpid"},
1718         {Opt_grpid, "bsdgroups"},
1719         {Opt_nogrpid, "nogrpid"},
1720         {Opt_nogrpid, "sysvgroups"},
1721         {Opt_resgid, "resgid=%u"},
1722         {Opt_resuid, "resuid=%u"},
1723         {Opt_sb, "sb=%u"},
1724         {Opt_err_cont, "errors=continue"},
1725         {Opt_err_panic, "errors=panic"},
1726         {Opt_err_ro, "errors=remount-ro"},
1727         {Opt_nouid32, "nouid32"},
1728         {Opt_debug, "debug"},
1729         {Opt_removed, "oldalloc"},
1730         {Opt_removed, "orlov"},
1731         {Opt_user_xattr, "user_xattr"},
1732         {Opt_nouser_xattr, "nouser_xattr"},
1733         {Opt_acl, "acl"},
1734         {Opt_noacl, "noacl"},
1735         {Opt_noload, "norecovery"},
1736         {Opt_noload, "noload"},
1737         {Opt_removed, "nobh"},
1738         {Opt_removed, "bh"},
1739         {Opt_commit, "commit=%u"},
1740         {Opt_min_batch_time, "min_batch_time=%u"},
1741         {Opt_max_batch_time, "max_batch_time=%u"},
1742         {Opt_journal_dev, "journal_dev=%u"},
1743         {Opt_journal_path, "journal_path=%s"},
1744         {Opt_journal_checksum, "journal_checksum"},
1745         {Opt_nojournal_checksum, "nojournal_checksum"},
1746         {Opt_journal_async_commit, "journal_async_commit"},
1747         {Opt_abort, "abort"},
1748         {Opt_data_journal, "data=journal"},
1749         {Opt_data_ordered, "data=ordered"},
1750         {Opt_data_writeback, "data=writeback"},
1751         {Opt_data_err_abort, "data_err=abort"},
1752         {Opt_data_err_ignore, "data_err=ignore"},
1753         {Opt_offusrjquota, "usrjquota="},
1754         {Opt_usrjquota, "usrjquota=%s"},
1755         {Opt_offgrpjquota, "grpjquota="},
1756         {Opt_grpjquota, "grpjquota=%s"},
1757         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1758         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1759         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1760         {Opt_grpquota, "grpquota"},
1761         {Opt_noquota, "noquota"},
1762         {Opt_quota, "quota"},
1763         {Opt_usrquota, "usrquota"},
1764         {Opt_prjquota, "prjquota"},
1765         {Opt_barrier, "barrier=%u"},
1766         {Opt_barrier, "barrier"},
1767         {Opt_nobarrier, "nobarrier"},
1768         {Opt_i_version, "i_version"},
1769         {Opt_dax, "dax"},
1770         {Opt_dax_always, "dax=always"},
1771         {Opt_dax_inode, "dax=inode"},
1772         {Opt_dax_never, "dax=never"},
1773         {Opt_stripe, "stripe=%u"},
1774         {Opt_delalloc, "delalloc"},
1775         {Opt_warn_on_error, "warn_on_error"},
1776         {Opt_nowarn_on_error, "nowarn_on_error"},
1777         {Opt_lazytime, "lazytime"},
1778         {Opt_nolazytime, "nolazytime"},
1779         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1780         {Opt_nodelalloc, "nodelalloc"},
1781         {Opt_removed, "mblk_io_submit"},
1782         {Opt_removed, "nomblk_io_submit"},
1783         {Opt_block_validity, "block_validity"},
1784         {Opt_noblock_validity, "noblock_validity"},
1785         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1786         {Opt_journal_ioprio, "journal_ioprio=%u"},
1787         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1788         {Opt_auto_da_alloc, "auto_da_alloc"},
1789         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1790         {Opt_dioread_nolock, "dioread_nolock"},
1791         {Opt_dioread_lock, "nodioread_nolock"},
1792         {Opt_dioread_lock, "dioread_lock"},
1793         {Opt_discard, "discard"},
1794         {Opt_nodiscard, "nodiscard"},
1795         {Opt_init_itable, "init_itable=%u"},
1796         {Opt_init_itable, "init_itable"},
1797         {Opt_noinit_itable, "noinit_itable"},
1798 #ifdef CONFIG_EXT4_DEBUG
1799         {Opt_fc_debug_force, "fc_debug_force"},
1800         {Opt_fc_debug_max_replay, "fc_debug_max_replay=%u"},
1801 #endif
1802         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1803         {Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1804         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1805         {Opt_inlinecrypt, "inlinecrypt"},
1806         {Opt_nombcache, "nombcache"},
1807         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1808         {Opt_prefetch_block_bitmaps, "prefetch_block_bitmaps"},
1809         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1810         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1811         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1812         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1813         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1814         {Opt_err, NULL},
1815 };
1816
1817 static ext4_fsblk_t get_sb_block(void **data)
1818 {
1819         ext4_fsblk_t    sb_block;
1820         char            *options = (char *) *data;
1821
1822         if (!options || strncmp(options, "sb=", 3) != 0)
1823                 return 1;       /* Default location */
1824
1825         options += 3;
1826         /* TODO: use simple_strtoll with >32bit ext4 */
1827         sb_block = simple_strtoul(options, &options, 0);
1828         if (*options && *options != ',') {
1829                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1830                        (char *) *data);
1831                 return 1;
1832         }
1833         if (*options == ',')
1834                 options++;
1835         *data = (void *) options;
1836
1837         return sb_block;
1838 }
1839
1840 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1841 static const char deprecated_msg[] =
1842         "Mount option \"%s\" will be removed by %s\n"
1843         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1844
1845 #ifdef CONFIG_QUOTA
1846 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1847 {
1848         struct ext4_sb_info *sbi = EXT4_SB(sb);
1849         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1850         int ret = -1;
1851
1852         if (sb_any_quota_loaded(sb) && !old_qname) {
1853                 ext4_msg(sb, KERN_ERR,
1854                         "Cannot change journaled "
1855                         "quota options when quota turned on");
1856                 return -1;
1857         }
1858         if (ext4_has_feature_quota(sb)) {
1859                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1860                          "ignored when QUOTA feature is enabled");
1861                 return 1;
1862         }
1863         qname = match_strdup(args);
1864         if (!qname) {
1865                 ext4_msg(sb, KERN_ERR,
1866                         "Not enough memory for storing quotafile name");
1867                 return -1;
1868         }
1869         if (old_qname) {
1870                 if (strcmp(old_qname, qname) == 0)
1871                         ret = 1;
1872                 else
1873                         ext4_msg(sb, KERN_ERR,
1874                                  "%s quota file already specified",
1875                                  QTYPE2NAME(qtype));
1876                 goto errout;
1877         }
1878         if (strchr(qname, '/')) {
1879                 ext4_msg(sb, KERN_ERR,
1880                         "quotafile must be on filesystem root");
1881                 goto errout;
1882         }
1883         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1884         set_opt(sb, QUOTA);
1885         return 1;
1886 errout:
1887         kfree(qname);
1888         return ret;
1889 }
1890
1891 static int clear_qf_name(struct super_block *sb, int qtype)
1892 {
1893
1894         struct ext4_sb_info *sbi = EXT4_SB(sb);
1895         char *old_qname = get_qf_name(sb, sbi, qtype);
1896
1897         if (sb_any_quota_loaded(sb) && old_qname) {
1898                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1899                         " when quota turned on");
1900                 return -1;
1901         }
1902         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1903         synchronize_rcu();
1904         kfree(old_qname);
1905         return 1;
1906 }
1907 #endif
1908
1909 #define MOPT_SET        0x0001
1910 #define MOPT_CLEAR      0x0002
1911 #define MOPT_NOSUPPORT  0x0004
1912 #define MOPT_EXPLICIT   0x0008
1913 #define MOPT_CLEAR_ERR  0x0010
1914 #define MOPT_GTE0       0x0020
1915 #ifdef CONFIG_QUOTA
1916 #define MOPT_Q          0
1917 #define MOPT_QFMT       0x0040
1918 #else
1919 #define MOPT_Q          MOPT_NOSUPPORT
1920 #define MOPT_QFMT       MOPT_NOSUPPORT
1921 #endif
1922 #define MOPT_DATAJ      0x0080
1923 #define MOPT_NO_EXT2    0x0100
1924 #define MOPT_NO_EXT3    0x0200
1925 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1926 #define MOPT_STRING     0x0400
1927 #define MOPT_SKIP       0x0800
1928 #define MOPT_2          0x1000
1929
1930 static const struct mount_opts {
1931         int     token;
1932         int     mount_opt;
1933         int     flags;
1934 } ext4_mount_opts[] = {
1935         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1936         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1937         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1938         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1939         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1940         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1941         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1942          MOPT_EXT4_ONLY | MOPT_SET},
1943         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1944          MOPT_EXT4_ONLY | MOPT_CLEAR},
1945         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1946         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1947         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1948          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1949         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1950          MOPT_EXT4_ONLY | MOPT_CLEAR},
1951         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1952         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1953         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1954          MOPT_EXT4_ONLY | MOPT_CLEAR},
1955         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1956          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1957         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1958                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1959          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1960         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1961         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1962         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1963         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1964         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1965          MOPT_NO_EXT2},
1966         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1967          MOPT_NO_EXT2},
1968         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1969         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1970         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1971         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1972         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1973         {Opt_commit, 0, MOPT_GTE0},
1974         {Opt_max_batch_time, 0, MOPT_GTE0},
1975         {Opt_min_batch_time, 0, MOPT_GTE0},
1976         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1977         {Opt_init_itable, 0, MOPT_GTE0},
1978         {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1979         {Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1980                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1981         {Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1982                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1983         {Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1984                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1985         {Opt_stripe, 0, MOPT_GTE0},
1986         {Opt_resuid, 0, MOPT_GTE0},
1987         {Opt_resgid, 0, MOPT_GTE0},
1988         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1989         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1990         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1991         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1992         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1993         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1994          MOPT_NO_EXT2 | MOPT_DATAJ},
1995         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1996         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1997 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1998         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1999         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
2000 #else
2001         {Opt_acl, 0, MOPT_NOSUPPORT},
2002         {Opt_noacl, 0, MOPT_NOSUPPORT},
2003 #endif
2004         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
2005         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
2006         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
2007         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
2008         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
2009                                                         MOPT_SET | MOPT_Q},
2010         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
2011                                                         MOPT_SET | MOPT_Q},
2012         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
2013                                                         MOPT_SET | MOPT_Q},
2014         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2015                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
2016                                                         MOPT_CLEAR | MOPT_Q},
2017         {Opt_usrjquota, 0, MOPT_Q | MOPT_STRING},
2018         {Opt_grpjquota, 0, MOPT_Q | MOPT_STRING},
2019         {Opt_offusrjquota, 0, MOPT_Q},
2020         {Opt_offgrpjquota, 0, MOPT_Q},
2021         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
2022         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
2023         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
2024         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
2025         {Opt_test_dummy_encryption, 0, MOPT_STRING},
2026         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
2027         {Opt_prefetch_block_bitmaps, EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS,
2028          MOPT_SET},
2029 #ifdef CONFIG_EXT4_DEBUG
2030         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
2031          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
2032         {Opt_fc_debug_max_replay, 0, MOPT_GTE0},
2033 #endif
2034         {Opt_err, 0, 0}
2035 };
2036
2037 #ifdef CONFIG_UNICODE
2038 static const struct ext4_sb_encodings {
2039         __u16 magic;
2040         char *name;
2041         char *version;
2042 } ext4_sb_encoding_map[] = {
2043         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
2044 };
2045
2046 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
2047                                  const struct ext4_sb_encodings **encoding,
2048                                  __u16 *flags)
2049 {
2050         __u16 magic = le16_to_cpu(es->s_encoding);
2051         int i;
2052
2053         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
2054                 if (magic == ext4_sb_encoding_map[i].magic)
2055                         break;
2056
2057         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
2058                 return -EINVAL;
2059
2060         *encoding = &ext4_sb_encoding_map[i];
2061         *flags = le16_to_cpu(es->s_encoding_flags);
2062
2063         return 0;
2064 }
2065 #endif
2066
2067 static int ext4_set_test_dummy_encryption(struct super_block *sb,
2068                                           const char *opt,
2069                                           const substring_t *arg,
2070                                           bool is_remount)
2071 {
2072 #ifdef CONFIG_FS_ENCRYPTION
2073         struct ext4_sb_info *sbi = EXT4_SB(sb);
2074         int err;
2075
2076         /*
2077          * This mount option is just for testing, and it's not worthwhile to
2078          * implement the extra complexity (e.g. RCU protection) that would be
2079          * needed to allow it to be set or changed during remount.  We do allow
2080          * it to be specified during remount, but only if there is no change.
2081          */
2082         if (is_remount && !sbi->s_dummy_enc_policy.policy) {
2083                 ext4_msg(sb, KERN_WARNING,
2084                          "Can't set test_dummy_encryption on remount");
2085                 return -1;
2086         }
2087         err = fscrypt_set_test_dummy_encryption(sb, arg->from,
2088                                                 &sbi->s_dummy_enc_policy);
2089         if (err) {
2090                 if (err == -EEXIST)
2091                         ext4_msg(sb, KERN_WARNING,
2092                                  "Can't change test_dummy_encryption on remount");
2093                 else if (err == -EINVAL)
2094                         ext4_msg(sb, KERN_WARNING,
2095                                  "Value of option \"%s\" is unrecognized", opt);
2096                 else
2097                         ext4_msg(sb, KERN_WARNING,
2098                                  "Error processing option \"%s\" [%d]",
2099                                  opt, err);
2100                 return -1;
2101         }
2102         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2103 #else
2104         ext4_msg(sb, KERN_WARNING,
2105                  "Test dummy encryption mount option ignored");
2106 #endif
2107         return 1;
2108 }
2109
2110 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
2111                             substring_t *args, unsigned long *journal_devnum,
2112                             unsigned int *journal_ioprio, int is_remount)
2113 {
2114         struct ext4_sb_info *sbi = EXT4_SB(sb);
2115         const struct mount_opts *m;
2116         kuid_t uid;
2117         kgid_t gid;
2118         int arg = 0;
2119
2120 #ifdef CONFIG_QUOTA
2121         if (token == Opt_usrjquota)
2122                 return set_qf_name(sb, USRQUOTA, &args[0]);
2123         else if (token == Opt_grpjquota)
2124                 return set_qf_name(sb, GRPQUOTA, &args[0]);
2125         else if (token == Opt_offusrjquota)
2126                 return clear_qf_name(sb, USRQUOTA);
2127         else if (token == Opt_offgrpjquota)
2128                 return clear_qf_name(sb, GRPQUOTA);
2129 #endif
2130         switch (token) {
2131         case Opt_noacl:
2132         case Opt_nouser_xattr:
2133                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
2134                 break;
2135         case Opt_sb:
2136                 return 1;       /* handled by get_sb_block() */
2137         case Opt_removed:
2138                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
2139                 return 1;
2140         case Opt_abort:
2141                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
2142                 return 1;
2143         case Opt_i_version:
2144                 sb->s_flags |= SB_I_VERSION;
2145                 return 1;
2146         case Opt_lazytime:
2147                 sb->s_flags |= SB_LAZYTIME;
2148                 return 1;
2149         case Opt_nolazytime:
2150                 sb->s_flags &= ~SB_LAZYTIME;
2151                 return 1;
2152         case Opt_inlinecrypt:
2153 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2154                 sb->s_flags |= SB_INLINECRYPT;
2155 #else
2156                 ext4_msg(sb, KERN_ERR, "inline encryption not supported");
2157 #endif
2158                 return 1;
2159         }
2160
2161         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2162                 if (token == m->token)
2163                         break;
2164
2165         if (m->token == Opt_err) {
2166                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
2167                          "or missing value", opt);
2168                 return -1;
2169         }
2170
2171         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2172                 ext4_msg(sb, KERN_ERR,
2173                          "Mount option \"%s\" incompatible with ext2", opt);
2174                 return -1;
2175         }
2176         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2177                 ext4_msg(sb, KERN_ERR,
2178                          "Mount option \"%s\" incompatible with ext3", opt);
2179                 return -1;
2180         }
2181
2182         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
2183                 return -1;
2184         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
2185                 return -1;
2186         if (m->flags & MOPT_EXPLICIT) {
2187                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2188                         set_opt2(sb, EXPLICIT_DELALLOC);
2189                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2190                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
2191                 } else
2192                         return -1;
2193         }
2194         if (m->flags & MOPT_CLEAR_ERR)
2195                 clear_opt(sb, ERRORS_MASK);
2196         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
2197                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
2198                          "options when quota turned on");
2199                 return -1;
2200         }
2201
2202         if (m->flags & MOPT_NOSUPPORT) {
2203                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
2204         } else if (token == Opt_commit) {
2205                 if (arg == 0)
2206                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2207                 else if (arg > INT_MAX / HZ) {
2208                         ext4_msg(sb, KERN_ERR,
2209                                  "Invalid commit interval %d, "
2210                                  "must be smaller than %d",
2211                                  arg, INT_MAX / HZ);
2212                         return -1;
2213                 }
2214                 sbi->s_commit_interval = HZ * arg;
2215         } else if (token == Opt_debug_want_extra_isize) {
2216                 if ((arg & 1) ||
2217                     (arg < 4) ||
2218                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2219                         ext4_msg(sb, KERN_ERR,
2220                                  "Invalid want_extra_isize %d", arg);
2221                         return -1;
2222                 }
2223                 sbi->s_want_extra_isize = arg;
2224         } else if (token == Opt_max_batch_time) {
2225                 sbi->s_max_batch_time = arg;
2226         } else if (token == Opt_min_batch_time) {
2227                 sbi->s_min_batch_time = arg;
2228         } else if (token == Opt_inode_readahead_blks) {
2229                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2230                         ext4_msg(sb, KERN_ERR,
2231                                  "EXT4-fs: inode_readahead_blks must be "
2232                                  "0 or a power of 2 smaller than 2^31");
2233                         return -1;
2234                 }
2235                 sbi->s_inode_readahead_blks = arg;
2236         } else if (token == Opt_init_itable) {
2237                 set_opt(sb, INIT_INODE_TABLE);
2238                 if (!args->from)
2239                         arg = EXT4_DEF_LI_WAIT_MULT;
2240                 sbi->s_li_wait_mult = arg;
2241         } else if (token == Opt_max_dir_size_kb) {
2242                 sbi->s_max_dir_size_kb = arg;
2243 #ifdef CONFIG_EXT4_DEBUG
2244         } else if (token == Opt_fc_debug_max_replay) {
2245                 sbi->s_fc_debug_max_replay = arg;
2246 #endif
2247         } else if (token == Opt_stripe) {
2248                 sbi->s_stripe = arg;
2249         } else if (token == Opt_resuid) {
2250                 uid = make_kuid(current_user_ns(), arg);
2251                 if (!uid_valid(uid)) {
2252                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2253                         return -1;
2254                 }
2255                 sbi->s_resuid = uid;
2256         } else if (token == Opt_resgid) {
2257                 gid = make_kgid(current_user_ns(), arg);
2258                 if (!gid_valid(gid)) {
2259                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2260                         return -1;
2261                 }
2262                 sbi->s_resgid = gid;
2263         } else if (token == Opt_journal_dev) {
2264                 if (is_remount) {
2265                         ext4_msg(sb, KERN_ERR,
2266                                  "Cannot specify journal on remount");
2267                         return -1;
2268                 }
2269                 *journal_devnum = arg;
2270         } else if (token == Opt_journal_path) {
2271                 char *journal_path;
2272                 struct inode *journal_inode;
2273                 struct path path;
2274                 int error;
2275
2276                 if (is_remount) {
2277                         ext4_msg(sb, KERN_ERR,
2278                                  "Cannot specify journal on remount");
2279                         return -1;
2280                 }
2281                 journal_path = match_strdup(&args[0]);
2282                 if (!journal_path) {
2283                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2284                                 "journal device string");
2285                         return -1;
2286                 }
2287
2288                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2289                 if (error) {
2290                         ext4_msg(sb, KERN_ERR, "error: could not find "
2291                                 "journal device path: error %d", error);
2292                         kfree(journal_path);
2293                         return -1;
2294                 }
2295
2296                 journal_inode = d_inode(path.dentry);
2297                 if (!S_ISBLK(journal_inode->i_mode)) {
2298                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2299                                 "is not a block device", journal_path);
2300                         path_put(&path);
2301                         kfree(journal_path);
2302                         return -1;
2303                 }
2304
2305                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
2306                 path_put(&path);
2307                 kfree(journal_path);
2308         } else if (token == Opt_journal_ioprio) {
2309                 if (arg > 7) {
2310                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2311                                  " (must be 0-7)");
2312                         return -1;
2313                 }
2314                 *journal_ioprio =
2315                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2316         } else if (token == Opt_test_dummy_encryption) {
2317                 return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2318                                                       is_remount);
2319         } else if (m->flags & MOPT_DATAJ) {
2320                 if (is_remount) {
2321                         if (!sbi->s_journal)
2322                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2323                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2324                                 ext4_msg(sb, KERN_ERR,
2325                                          "Cannot change data mode on remount");
2326                                 return -1;
2327                         }
2328                 } else {
2329                         clear_opt(sb, DATA_FLAGS);
2330                         sbi->s_mount_opt |= m->mount_opt;
2331                 }
2332 #ifdef CONFIG_QUOTA
2333         } else if (m->flags & MOPT_QFMT) {
2334                 if (sb_any_quota_loaded(sb) &&
2335                     sbi->s_jquota_fmt != m->mount_opt) {
2336                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2337                                  "quota options when quota turned on");
2338                         return -1;
2339                 }
2340                 if (ext4_has_feature_quota(sb)) {
2341                         ext4_msg(sb, KERN_INFO,
2342                                  "Quota format mount options ignored "
2343                                  "when QUOTA feature is enabled");
2344                         return 1;
2345                 }
2346                 sbi->s_jquota_fmt = m->mount_opt;
2347 #endif
2348         } else if (token == Opt_dax || token == Opt_dax_always ||
2349                    token == Opt_dax_inode || token == Opt_dax_never) {
2350 #ifdef CONFIG_FS_DAX
2351                 switch (token) {
2352                 case Opt_dax:
2353                 case Opt_dax_always:
2354                         if (is_remount &&
2355                             (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2356                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2357                         fail_dax_change_remount:
2358                                 ext4_msg(sb, KERN_ERR, "can't change "
2359                                          "dax mount option while remounting");
2360                                 return -1;
2361                         }
2362                         if (is_remount &&
2363                             (test_opt(sb, DATA_FLAGS) ==
2364                              EXT4_MOUNT_JOURNAL_DATA)) {
2365                                     ext4_msg(sb, KERN_ERR, "can't mount with "
2366                                              "both data=journal and dax");
2367                                     return -1;
2368                         }
2369                         ext4_msg(sb, KERN_WARNING,
2370                                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2371                         sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2372                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2373                         break;
2374                 case Opt_dax_never:
2375                         if (is_remount &&
2376                             (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2377                              (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2378                                 goto fail_dax_change_remount;
2379                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2380                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2381                         break;
2382                 case Opt_dax_inode:
2383                         if (is_remount &&
2384                             ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2385                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2386                              !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2387                                 goto fail_dax_change_remount;
2388                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2389                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2390                         /* Strictly for printing options */
2391                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2392                         break;
2393                 }
2394 #else
2395                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2396                 sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2397                 sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2398                 return -1;
2399 #endif
2400         } else if (token == Opt_data_err_abort) {
2401                 sbi->s_mount_opt |= m->mount_opt;
2402         } else if (token == Opt_data_err_ignore) {
2403                 sbi->s_mount_opt &= ~m->mount_opt;
2404         } else {
2405                 if (!args->from)
2406                         arg = 1;
2407                 if (m->flags & MOPT_CLEAR)
2408                         arg = !arg;
2409                 else if (unlikely(!(m->flags & MOPT_SET))) {
2410                         ext4_msg(sb, KERN_WARNING,
2411                                  "buggy handling of option %s", opt);
2412                         WARN_ON(1);
2413                         return -1;
2414                 }
2415                 if (m->flags & MOPT_2) {
2416                         if (arg != 0)
2417                                 sbi->s_mount_opt2 |= m->mount_opt;
2418                         else
2419                                 sbi->s_mount_opt2 &= ~m->mount_opt;
2420                 } else {
2421                         if (arg != 0)
2422                                 sbi->s_mount_opt |= m->mount_opt;
2423                         else
2424                                 sbi->s_mount_opt &= ~m->mount_opt;
2425                 }
2426         }
2427         return 1;
2428 }
2429
2430 static int parse_options(char *options, struct super_block *sb,
2431                          unsigned long *journal_devnum,
2432                          unsigned int *journal_ioprio,
2433                          int is_remount)
2434 {
2435         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2436         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2437         substring_t args[MAX_OPT_ARGS];
2438         int token;
2439
2440         if (!options)
2441                 return 1;
2442
2443         while ((p = strsep(&options, ",")) != NULL) {
2444                 if (!*p)
2445                         continue;
2446                 /*
2447                  * Initialize args struct so we know whether arg was
2448                  * found; some options take optional arguments.
2449                  */
2450                 args[0].to = args[0].from = NULL;
2451                 token = match_token(p, tokens, args);
2452                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2453                                      journal_ioprio, is_remount) < 0)
2454                         return 0;
2455         }
2456 #ifdef CONFIG_QUOTA
2457         /*
2458          * We do the test below only for project quotas. 'usrquota' and
2459          * 'grpquota' mount options are allowed even without quota feature
2460          * to support legacy quotas in quota files.
2461          */
2462         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2463                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2464                          "Cannot enable project quota enforcement.");
2465                 return 0;
2466         }
2467         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2468         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2469         if (usr_qf_name || grp_qf_name) {
2470                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2471                         clear_opt(sb, USRQUOTA);
2472
2473                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2474                         clear_opt(sb, GRPQUOTA);
2475
2476                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2477                         ext4_msg(sb, KERN_ERR, "old and new quota "
2478                                         "format mixing");
2479                         return 0;
2480                 }
2481
2482                 if (!sbi->s_jquota_fmt) {
2483                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2484                                         "not specified");
2485                         return 0;
2486                 }
2487         }
2488 #endif
2489         if (test_opt(sb, DIOREAD_NOLOCK)) {
2490                 int blocksize =
2491                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2492                 if (blocksize < PAGE_SIZE)
2493                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2494                                  "experimental mount option 'dioread_nolock' "
2495                                  "for blocksize < PAGE_SIZE");
2496         }
2497         return 1;
2498 }
2499
2500 static inline void ext4_show_quota_options(struct seq_file *seq,
2501                                            struct super_block *sb)
2502 {
2503 #if defined(CONFIG_QUOTA)
2504         struct ext4_sb_info *sbi = EXT4_SB(sb);
2505         char *usr_qf_name, *grp_qf_name;
2506
2507         if (sbi->s_jquota_fmt) {
2508                 char *fmtname = "";
2509
2510                 switch (sbi->s_jquota_fmt) {
2511                 case QFMT_VFS_OLD:
2512                         fmtname = "vfsold";
2513                         break;
2514                 case QFMT_VFS_V0:
2515                         fmtname = "vfsv0";
2516                         break;
2517                 case QFMT_VFS_V1:
2518                         fmtname = "vfsv1";
2519                         break;
2520                 }
2521                 seq_printf(seq, ",jqfmt=%s", fmtname);
2522         }
2523
2524         rcu_read_lock();
2525         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2526         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2527         if (usr_qf_name)
2528                 seq_show_option(seq, "usrjquota", usr_qf_name);
2529         if (grp_qf_name)
2530                 seq_show_option(seq, "grpjquota", grp_qf_name);
2531         rcu_read_unlock();
2532 #endif
2533 }
2534
2535 static const char *token2str(int token)
2536 {
2537         const struct match_token *t;
2538
2539         for (t = tokens; t->token != Opt_err; t++)
2540                 if (t->token == token && !strchr(t->pattern, '='))
2541                         break;
2542         return t->pattern;
2543 }
2544
2545 /*
2546  * Show an option if
2547  *  - it's set to a non-default value OR
2548  *  - if the per-sb default is different from the global default
2549  */
2550 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2551                               int nodefs)
2552 {
2553         struct ext4_sb_info *sbi = EXT4_SB(sb);
2554         struct ext4_super_block *es = sbi->s_es;
2555         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2556         const struct mount_opts *m;
2557         char sep = nodefs ? '\n' : ',';
2558
2559 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2560 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2561
2562         if (sbi->s_sb_block != 1)
2563                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2564
2565         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2566                 int want_set = m->flags & MOPT_SET;
2567                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2568                     (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2569                         continue;
2570                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2571                         continue; /* skip if same as the default */
2572                 if ((want_set &&
2573                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2574                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2575                         continue; /* select Opt_noFoo vs Opt_Foo */
2576                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2577         }
2578
2579         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2580             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2581                 SEQ_OPTS_PRINT("resuid=%u",
2582                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2583         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2584             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2585                 SEQ_OPTS_PRINT("resgid=%u",
2586                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2587         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2588         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2589                 SEQ_OPTS_PUTS("errors=remount-ro");
2590         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2591                 SEQ_OPTS_PUTS("errors=continue");
2592         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2593                 SEQ_OPTS_PUTS("errors=panic");
2594         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2595                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2596         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2597                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2598         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2599                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2600         if (sb->s_flags & SB_I_VERSION)
2601                 SEQ_OPTS_PUTS("i_version");
2602         if (nodefs || sbi->s_stripe)
2603                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2604         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2605                         (sbi->s_mount_opt ^ def_mount_opt)) {
2606                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2607                         SEQ_OPTS_PUTS("data=journal");
2608                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2609                         SEQ_OPTS_PUTS("data=ordered");
2610                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2611                         SEQ_OPTS_PUTS("data=writeback");
2612         }
2613         if (nodefs ||
2614             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2615                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2616                                sbi->s_inode_readahead_blks);
2617
2618         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2619                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2620                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2621         if (nodefs || sbi->s_max_dir_size_kb)
2622                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2623         if (test_opt(sb, DATA_ERR_ABORT))
2624                 SEQ_OPTS_PUTS("data_err=abort");
2625
2626         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2627
2628         if (sb->s_flags & SB_INLINECRYPT)
2629                 SEQ_OPTS_PUTS("inlinecrypt");
2630
2631         if (test_opt(sb, DAX_ALWAYS)) {
2632                 if (IS_EXT2_SB(sb))
2633                         SEQ_OPTS_PUTS("dax");
2634                 else
2635                         SEQ_OPTS_PUTS("dax=always");
2636         } else if (test_opt2(sb, DAX_NEVER)) {
2637                 SEQ_OPTS_PUTS("dax=never");
2638         } else if (test_opt2(sb, DAX_INODE)) {
2639                 SEQ_OPTS_PUTS("dax=inode");
2640         }
2641         ext4_show_quota_options(seq, sb);
2642         return 0;
2643 }
2644
2645 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2646 {
2647         return _ext4_show_options(seq, root->d_sb, 0);
2648 }
2649
2650 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2651 {
2652         struct super_block *sb = seq->private;
2653         int rc;
2654
2655         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2656         rc = _ext4_show_options(seq, sb, 1);
2657         seq_puts(seq, "\n");
2658         return rc;
2659 }
2660
2661 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2662                             int read_only)
2663 {
2664         struct ext4_sb_info *sbi = EXT4_SB(sb);
2665         int err = 0;
2666
2667         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2668                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2669                          "forcing read-only mode");
2670                 err = -EROFS;
2671                 goto done;
2672         }
2673         if (read_only)
2674                 goto done;
2675         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2676                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2677                          "running e2fsck is recommended");
2678         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2679                 ext4_msg(sb, KERN_WARNING,
2680                          "warning: mounting fs with errors, "
2681                          "running e2fsck is recommended");
2682         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2683                  le16_to_cpu(es->s_mnt_count) >=
2684                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2685                 ext4_msg(sb, KERN_WARNING,
2686                          "warning: maximal mount count reached, "
2687                          "running e2fsck is recommended");
2688         else if (le32_to_cpu(es->s_checkinterval) &&
2689                  (ext4_get_tstamp(es, s_lastcheck) +
2690                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2691                 ext4_msg(sb, KERN_WARNING,
2692                          "warning: checktime reached, "
2693                          "running e2fsck is recommended");
2694         if (!sbi->s_journal)
2695                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2696         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2697                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2698         le16_add_cpu(&es->s_mnt_count, 1);
2699         ext4_update_tstamp(es, s_mtime);
2700         if (sbi->s_journal)
2701                 ext4_set_feature_journal_needs_recovery(sb);
2702
2703         err = ext4_commit_super(sb, 1);
2704 done:
2705         if (test_opt(sb, DEBUG))
2706                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2707                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2708                         sb->s_blocksize,
2709                         sbi->s_groups_count,
2710                         EXT4_BLOCKS_PER_GROUP(sb),
2711                         EXT4_INODES_PER_GROUP(sb),
2712                         sbi->s_mount_opt, sbi->s_mount_opt2);
2713
2714         cleancache_init_fs(sb);
2715         return err;
2716 }
2717
2718 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2719 {
2720         struct ext4_sb_info *sbi = EXT4_SB(sb);
2721         struct flex_groups **old_groups, **new_groups;
2722         int size, i, j;
2723
2724         if (!sbi->s_log_groups_per_flex)
2725                 return 0;
2726
2727         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2728         if (size <= sbi->s_flex_groups_allocated)
2729                 return 0;
2730
2731         new_groups = kvzalloc(roundup_pow_of_two(size *
2732                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2733         if (!new_groups) {
2734                 ext4_msg(sb, KERN_ERR,
2735                          "not enough memory for %d flex group pointers", size);
2736                 return -ENOMEM;
2737         }
2738         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2739                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2740                                          sizeof(struct flex_groups)),
2741                                          GFP_KERNEL);
2742                 if (!new_groups[i]) {
2743                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2744                                 kvfree(new_groups[j]);
2745                         kvfree(new_groups);
2746                         ext4_msg(sb, KERN_ERR,
2747                                  "not enough memory for %d flex groups", size);
2748                         return -ENOMEM;
2749                 }
2750         }
2751         rcu_read_lock();
2752         old_groups = rcu_dereference(sbi->s_flex_groups);
2753         if (old_groups)
2754                 memcpy(new_groups, old_groups,
2755                        (sbi->s_flex_groups_allocated *
2756                         sizeof(struct flex_groups *)));
2757         rcu_read_unlock();
2758         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2759         sbi->s_flex_groups_allocated = size;
2760         if (old_groups)
2761                 ext4_kvfree_array_rcu(old_groups);
2762         return 0;
2763 }
2764
2765 static int ext4_fill_flex_info(struct super_block *sb)
2766 {
2767         struct ext4_sb_info *sbi = EXT4_SB(sb);
2768         struct ext4_group_desc *gdp = NULL;
2769         struct flex_groups *fg;
2770         ext4_group_t flex_group;
2771         int i, err;
2772
2773         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2774         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2775                 sbi->s_log_groups_per_flex = 0;
2776                 return 1;
2777         }
2778
2779         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2780         if (err)
2781                 goto failed;
2782
2783         for (i = 0; i < sbi->s_groups_count; i++) {
2784                 gdp = ext4_get_group_desc(sb, i, NULL);
2785
2786                 flex_group = ext4_flex_group(sbi, i);
2787                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2788                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2789                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2790                              &fg->free_clusters);
2791                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2792         }
2793
2794         return 1;
2795 failed:
2796         return 0;
2797 }
2798
2799 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2800                                    struct ext4_group_desc *gdp)
2801 {
2802         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2803         __u16 crc = 0;
2804         __le32 le_group = cpu_to_le32(block_group);
2805         struct ext4_sb_info *sbi = EXT4_SB(sb);
2806
2807         if (ext4_has_metadata_csum(sbi->s_sb)) {
2808                 /* Use new metadata_csum algorithm */
2809                 __u32 csum32;
2810                 __u16 dummy_csum = 0;
2811
2812                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2813                                      sizeof(le_group));
2814                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2815                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2816                                      sizeof(dummy_csum));
2817                 offset += sizeof(dummy_csum);
2818                 if (offset < sbi->s_desc_size)
2819                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2820                                              sbi->s_desc_size - offset);
2821
2822                 crc = csum32 & 0xFFFF;
2823                 goto out;
2824         }
2825
2826         /* old crc16 code */
2827         if (!ext4_has_feature_gdt_csum(sb))
2828                 return 0;
2829
2830         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2831         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2832         crc = crc16(crc, (__u8 *)gdp, offset);
2833         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2834         /* for checksum of struct ext4_group_desc do the rest...*/
2835         if (ext4_has_feature_64bit(sb) &&
2836             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2837                 crc = crc16(crc, (__u8 *)gdp + offset,
2838                             le16_to_cpu(sbi->s_es->s_desc_size) -
2839                                 offset);
2840
2841 out:
2842         return cpu_to_le16(crc);
2843 }
2844
2845 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2846                                 struct ext4_group_desc *gdp)
2847 {
2848         if (ext4_has_group_desc_csum(sb) &&
2849             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2850                 return 0;
2851
2852         return 1;
2853 }
2854
2855 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2856                               struct ext4_group_desc *gdp)
2857 {
2858         if (!ext4_has_group_desc_csum(sb))
2859                 return;
2860         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2861 }
2862
2863 /* Called at mount-time, super-block is locked */
2864 static int ext4_check_descriptors(struct super_block *sb,
2865                                   ext4_fsblk_t sb_block,
2866                                   ext4_group_t *first_not_zeroed)
2867 {
2868         struct ext4_sb_info *sbi = EXT4_SB(sb);
2869         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2870         ext4_fsblk_t last_block;
2871         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2872         ext4_fsblk_t block_bitmap;
2873         ext4_fsblk_t inode_bitmap;
2874         ext4_fsblk_t inode_table;
2875         int flexbg_flag = 0;
2876         ext4_group_t i, grp = sbi->s_groups_count;
2877
2878         if (ext4_has_feature_flex_bg(sb))
2879                 flexbg_flag = 1;
2880
2881         ext4_debug("Checking group descriptors");
2882
2883         for (i = 0; i < sbi->s_groups_count; i++) {
2884                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2885
2886                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2887                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2888                 else
2889                         last_block = first_block +
2890                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2891
2892                 if ((grp == sbi->s_groups_count) &&
2893                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2894                         grp = i;
2895
2896                 block_bitmap = ext4_block_bitmap(sb, gdp);
2897                 if (block_bitmap == sb_block) {
2898                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2899                                  "Block bitmap for group %u overlaps "
2900                                  "superblock", i);
2901                         if (!sb_rdonly(sb))
2902                                 return 0;
2903                 }
2904                 if (block_bitmap >= sb_block + 1 &&
2905                     block_bitmap <= last_bg_block) {
2906                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2907                                  "Block bitmap for group %u overlaps "
2908                                  "block group descriptors", i);
2909                         if (!sb_rdonly(sb))
2910                                 return 0;
2911                 }
2912                 if (block_bitmap < first_block || block_bitmap > last_block) {
2913                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2914                                "Block bitmap for group %u not in group "
2915                                "(block %llu)!", i, block_bitmap);
2916                         return 0;
2917                 }
2918                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2919                 if (inode_bitmap == sb_block) {
2920                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2921                                  "Inode bitmap for group %u overlaps "
2922                                  "superblock", i);
2923                         if (!sb_rdonly(sb))
2924                                 return 0;
2925                 }
2926                 if (inode_bitmap >= sb_block + 1 &&
2927                     inode_bitmap <= last_bg_block) {
2928                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2929                                  "Inode bitmap for group %u overlaps "
2930                                  "block group descriptors", i);
2931                         if (!sb_rdonly(sb))
2932                                 return 0;
2933                 }
2934                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2935                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2936                                "Inode bitmap for group %u not in group "
2937                                "(block %llu)!", i, inode_bitmap);
2938                         return 0;
2939                 }
2940                 inode_table = ext4_inode_table(sb, gdp);
2941                 if (inode_table == sb_block) {
2942                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2943                                  "Inode table for group %u overlaps "
2944                                  "superblock", i);
2945                         if (!sb_rdonly(sb))
2946                                 return 0;
2947                 }
2948                 if (inode_table >= sb_block + 1 &&
2949                     inode_table <= last_bg_block) {
2950                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2951                                  "Inode table for group %u overlaps "
2952                                  "block group descriptors", i);
2953                         if (!sb_rdonly(sb))
2954                                 return 0;
2955                 }
2956                 if (inode_table < first_block ||
2957                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2958                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2959                                "Inode table for group %u not in group "
2960                                "(block %llu)!", i, inode_table);
2961                         return 0;
2962                 }
2963                 ext4_lock_group(sb, i);
2964                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2965                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2966                                  "Checksum for group %u failed (%u!=%u)",
2967                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2968                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2969                         if (!sb_rdonly(sb)) {
2970                                 ext4_unlock_group(sb, i);
2971                                 return 0;
2972                         }
2973                 }
2974                 ext4_unlock_group(sb, i);
2975                 if (!flexbg_flag)
2976                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2977         }
2978         if (NULL != first_not_zeroed)
2979                 *first_not_zeroed = grp;
2980         return 1;
2981 }
2982
2983 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2984  * the superblock) which were deleted from all directories, but held open by
2985  * a process at the time of a crash.  We walk the list and try to delete these
2986  * inodes at recovery time (only with a read-write filesystem).
2987  *
2988  * In order to keep the orphan inode chain consistent during traversal (in
2989  * case of crash during recovery), we link each inode into the superblock
2990  * orphan list_head and handle it the same way as an inode deletion during
2991  * normal operation (which journals the operations for us).
2992  *
2993  * We only do an iget() and an iput() on each inode, which is very safe if we
2994  * accidentally point at an in-use or already deleted inode.  The worst that
2995  * can happen in this case is that we get a "bit already cleared" message from
2996  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2997  * e2fsck was run on this filesystem, and it must have already done the orphan
2998  * inode cleanup for us, so we can safely abort without any further action.
2999  */
3000 static void ext4_orphan_cleanup(struct super_block *sb,
3001                                 struct ext4_super_block *es)
3002 {
3003         unsigned int s_flags = sb->s_flags;
3004         int ret, nr_orphans = 0, nr_truncates = 0;
3005 #ifdef CONFIG_QUOTA
3006         int quota_update = 0;
3007         int i;
3008 #endif
3009         if (!es->s_last_orphan) {
3010                 jbd_debug(4, "no orphan inodes to clean up\n");
3011                 return;
3012         }
3013
3014         if (bdev_read_only(sb->s_bdev)) {
3015                 ext4_msg(sb, KERN_ERR, "write access "
3016                         "unavailable, skipping orphan cleanup");
3017                 return;
3018         }
3019
3020         /* Check if feature set would not allow a r/w mount */
3021         if (!ext4_feature_set_ok(sb, 0)) {
3022                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
3023                          "unknown ROCOMPAT features");
3024                 return;
3025         }
3026
3027         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3028                 /* don't clear list on RO mount w/ errors */
3029                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
3030                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
3031                                   "clearing orphan list.\n");
3032                         es->s_last_orphan = 0;
3033                 }
3034                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3035                 return;
3036         }
3037
3038         if (s_flags & SB_RDONLY) {
3039                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
3040                 sb->s_flags &= ~SB_RDONLY;
3041         }
3042 #ifdef CONFIG_QUOTA
3043         /* Needed for iput() to work correctly and not trash data */
3044         sb->s_flags |= SB_ACTIVE;
3045
3046         /*
3047          * Turn on quotas which were not enabled for read-only mounts if
3048          * filesystem has quota feature, so that they are updated correctly.
3049          */
3050         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
3051                 int ret = ext4_enable_quotas(sb);
3052
3053                 if (!ret)
3054                         quota_update = 1;
3055                 else
3056                         ext4_msg(sb, KERN_ERR,
3057                                 "Cannot turn on quotas: error %d", ret);
3058         }
3059
3060         /* Turn on journaled quotas used for old sytle */
3061         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3062                 if (EXT4_SB(sb)->s_qf_names[i]) {
3063                         int ret = ext4_quota_on_mount(sb, i);
3064
3065                         if (!ret)
3066                                 quota_update = 1;
3067                         else
3068                                 ext4_msg(sb, KERN_ERR,
3069                                         "Cannot turn on journaled "
3070                                         "quota: type %d: error %d", i, ret);
3071                 }
3072         }
3073 #endif
3074
3075         while (es->s_last_orphan) {
3076                 struct inode *inode;
3077
3078                 /*
3079                  * We may have encountered an error during cleanup; if
3080                  * so, skip the rest.
3081                  */
3082                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3083                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3084                         es->s_last_orphan = 0;
3085                         break;
3086                 }
3087
3088                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
3089                 if (IS_ERR(inode)) {
3090                         es->s_last_orphan = 0;
3091                         break;
3092                 }
3093
3094                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
3095                 dquot_initialize(inode);
3096                 if (inode->i_nlink) {
3097                         if (test_opt(sb, DEBUG))
3098                                 ext4_msg(sb, KERN_DEBUG,
3099                                         "%s: truncating inode %lu to %lld bytes",
3100                                         __func__, inode->i_ino, inode->i_size);
3101                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
3102                                   inode->i_ino, inode->i_size);
3103                         inode_lock(inode);
3104                         truncate_inode_pages(inode->i_mapping, inode->i_size);
3105                         ret = ext4_truncate(inode);
3106                         if (ret)
3107                                 ext4_std_error(inode->i_sb, ret);
3108                         inode_unlock(inode);
3109                         nr_truncates++;
3110                 } else {
3111                         if (test_opt(sb, DEBUG))
3112                                 ext4_msg(sb, KERN_DEBUG,
3113                                         "%s: deleting unreferenced inode %lu",
3114                                         __func__, inode->i_ino);
3115                         jbd_debug(2, "deleting unreferenced inode %lu\n",
3116                                   inode->i_ino);
3117                         nr_orphans++;
3118                 }
3119                 iput(inode);  /* The delete magic happens here! */
3120         }
3121
3122 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
3123
3124         if (nr_orphans)
3125                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
3126                        PLURAL(nr_orphans));
3127         if (nr_truncates)
3128                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
3129                        PLURAL(nr_truncates));
3130 #ifdef CONFIG_QUOTA
3131         /* Turn off quotas if they were enabled for orphan cleanup */
3132         if (quota_update) {
3133                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3134                         if (sb_dqopt(sb)->files[i])
3135                                 dquot_quota_off(sb, i);
3136                 }
3137         }
3138 #endif
3139         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
3140 }
3141
3142 /*
3143  * Maximal extent format file size.
3144  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3145  * extent format containers, within a sector_t, and within i_blocks
3146  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3147  * so that won't be a limiting factor.
3148  *
3149  * However there is other limiting factor. We do store extents in the form
3150  * of starting block and length, hence the resulting length of the extent
3151  * covering maximum file size must fit into on-disk format containers as
3152  * well. Given that length is always by 1 unit bigger than max unit (because
3153  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3154  *
3155  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3156  */
3157 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3158 {
3159         loff_t res;
3160         loff_t upper_limit = MAX_LFS_FILESIZE;
3161
3162         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3163
3164         if (!has_huge_files) {
3165                 upper_limit = (1LL << 32) - 1;
3166
3167                 /* total blocks in file system block size */
3168                 upper_limit >>= (blkbits - 9);
3169                 upper_limit <<= blkbits;
3170         }
3171
3172         /*
3173          * 32-bit extent-start container, ee_block. We lower the maxbytes
3174          * by one fs block, so ee_len can cover the extent of maximum file
3175          * size
3176          */
3177         res = (1LL << 32) - 1;
3178         res <<= blkbits;
3179
3180         /* Sanity check against vm- & vfs- imposed limits */
3181         if (res > upper_limit)
3182                 res = upper_limit;
3183
3184         return res;
3185 }
3186
3187 /*
3188  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3189  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3190  * We need to be 1 filesystem block less than the 2^48 sector limit.
3191  */
3192 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3193 {
3194         loff_t res = EXT4_NDIR_BLOCKS;
3195         int meta_blocks;
3196         loff_t upper_limit;
3197         /* This is calculated to be the largest file size for a dense, block
3198          * mapped file such that the file's total number of 512-byte sectors,
3199          * including data and all indirect blocks, does not exceed (2^48 - 1).
3200          *
3201          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3202          * number of 512-byte sectors of the file.
3203          */
3204
3205         if (!has_huge_files) {
3206                 /*
3207                  * !has_huge_files or implies that the inode i_block field
3208                  * represents total file blocks in 2^32 512-byte sectors ==
3209                  * size of vfs inode i_blocks * 8
3210                  */
3211                 upper_limit = (1LL << 32) - 1;
3212
3213                 /* total blocks in file system block size */
3214                 upper_limit >>= (bits - 9);
3215
3216         } else {
3217                 /*
3218                  * We use 48 bit ext4_inode i_blocks
3219                  * With EXT4_HUGE_FILE_FL set the i_blocks
3220                  * represent total number of blocks in
3221                  * file system block size
3222                  */
3223                 upper_limit = (1LL << 48) - 1;
3224
3225         }
3226
3227         /* indirect blocks */
3228         meta_blocks = 1;
3229         /* double indirect blocks */
3230         meta_blocks += 1 + (1LL << (bits-2));
3231         /* tripple indirect blocks */
3232         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3233
3234         upper_limit -= meta_blocks;
3235         upper_limit <<= bits;
3236
3237         res += 1LL << (bits-2);
3238         res += 1LL << (2*(bits-2));
3239         res += 1LL << (3*(bits-2));
3240         res <<= bits;
3241         if (res > upper_limit)
3242                 res = upper_limit;
3243
3244         if (res > MAX_LFS_FILESIZE)
3245                 res = MAX_LFS_FILESIZE;
3246
3247         return res;
3248 }
3249
3250 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3251                                    ext4_fsblk_t logical_sb_block, int nr)
3252 {
3253         struct ext4_sb_info *sbi = EXT4_SB(sb);
3254         ext4_group_t bg, first_meta_bg;
3255         int has_super = 0;
3256
3257         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3258
3259         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3260                 return logical_sb_block + nr + 1;
3261         bg = sbi->s_desc_per_block * nr;
3262         if (ext4_bg_has_super(sb, bg))
3263                 has_super = 1;
3264
3265         /*
3266          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3267          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3268          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3269          * compensate.
3270          */
3271         if (sb->s_blocksize == 1024 && nr == 0 &&
3272             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3273                 has_super++;
3274
3275         return (has_super + ext4_group_first_block_no(sb, bg));
3276 }
3277
3278 /**
3279  * ext4_get_stripe_size: Get the stripe size.
3280  * @sbi: In memory super block info
3281  *
3282  * If we have specified it via mount option, then
3283  * use the mount option value. If the value specified at mount time is
3284  * greater than the blocks per group use the super block value.
3285  * If the super block value is greater than blocks per group return 0.
3286  * Allocator needs it be less than blocks per group.
3287  *
3288  */
3289 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3290 {
3291         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3292         unsigned long stripe_width =
3293                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3294         int ret;
3295
3296         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3297                 ret = sbi->s_stripe;
3298         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3299                 ret = stripe_width;
3300         else if (stride && stride <= sbi->s_blocks_per_group)
3301                 ret = stride;
3302         else
3303                 ret = 0;
3304
3305         /*
3306          * If the stripe width is 1, this makes no sense and
3307          * we set it to 0 to turn off stripe handling code.
3308          */
3309         if (ret <= 1)
3310                 ret = 0;
3311
3312         return ret;
3313 }
3314
3315 /*
3316  * Check whether this filesystem can be mounted based on
3317  * the features present and the RDONLY/RDWR mount requested.
3318  * Returns 1 if this filesystem can be mounted as requested,
3319  * 0 if it cannot be.
3320  */
3321 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3322 {
3323         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3324                 ext4_msg(sb, KERN_ERR,
3325                         "Couldn't mount because of "
3326                         "unsupported optional features (%x)",
3327                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3328                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3329                 return 0;
3330         }
3331
3332 #ifndef CONFIG_UNICODE
3333         if (ext4_has_feature_casefold(sb)) {
3334                 ext4_msg(sb, KERN_ERR,
3335                          "Filesystem with casefold feature cannot be "
3336                          "mounted without CONFIG_UNICODE");
3337                 return 0;
3338         }
3339 #endif
3340
3341         if (readonly)
3342                 return 1;
3343
3344         if (ext4_has_feature_readonly(sb)) {
3345                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3346                 sb->s_flags |= SB_RDONLY;
3347                 return 1;
3348         }
3349
3350         /* Check that feature set is OK for a read-write mount */
3351         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3352                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3353                          "unsupported optional features (%x)",
3354                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3355                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3356                 return 0;
3357         }
3358         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3359                 ext4_msg(sb, KERN_ERR,
3360                          "Can't support bigalloc feature without "
3361                          "extents feature\n");
3362                 return 0;
3363         }
3364
3365 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3366         if (!readonly && (ext4_has_feature_quota(sb) ||
3367                           ext4_has_feature_project(sb))) {
3368                 ext4_msg(sb, KERN_ERR,
3369                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3370                 return 0;
3371         }
3372 #endif  /* CONFIG_QUOTA */
3373         return 1;
3374 }
3375
3376 /*
3377  * This function is called once a day if we have errors logged
3378  * on the file system
3379  */
3380 static void print_daily_error_info(struct timer_list *t)
3381 {
3382         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3383         struct super_block *sb = sbi->s_sb;
3384         struct ext4_super_block *es = sbi->s_es;
3385
3386         if (es->s_error_count)
3387                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3388                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3389                          le32_to_cpu(es->s_error_count));
3390         if (es->s_first_error_time) {
3391                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3392                        sb->s_id,
3393                        ext4_get_tstamp(es, s_first_error_time),
3394                        (int) sizeof(es->s_first_error_func),
3395                        es->s_first_error_func,
3396                        le32_to_cpu(es->s_first_error_line));
3397                 if (es->s_first_error_ino)
3398                         printk(KERN_CONT ": inode %u",
3399                                le32_to_cpu(es->s_first_error_ino));
3400                 if (es->s_first_error_block)
3401                         printk(KERN_CONT ": block %llu", (unsigned long long)
3402                                le64_to_cpu(es->s_first_error_block));
3403                 printk(KERN_CONT "\n");
3404         }
3405         if (es->s_last_error_time) {
3406                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3407                        sb->s_id,
3408                        ext4_get_tstamp(es, s_last_error_time),
3409                        (int) sizeof(es->s_last_error_func),
3410                        es->s_last_error_func,
3411                        le32_to_cpu(es->s_last_error_line));
3412                 if (es->s_last_error_ino)
3413                         printk(KERN_CONT ": inode %u",
3414                                le32_to_cpu(es->s_last_error_ino));
3415                 if (es->s_last_error_block)
3416                         printk(KERN_CONT ": block %llu", (unsigned long long)
3417                                le64_to_cpu(es->s_last_error_block));
3418                 printk(KERN_CONT "\n");
3419         }
3420         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3421 }
3422
3423 /* Find next suitable group and run ext4_init_inode_table */
3424 static int ext4_run_li_request(struct ext4_li_request *elr)
3425 {
3426         struct ext4_group_desc *gdp = NULL;
3427         struct super_block *sb = elr->lr_super;
3428         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3429         ext4_group_t group = elr->lr_next_group;
3430         unsigned long timeout = 0;
3431         unsigned int prefetch_ios = 0;
3432         int ret = 0;
3433
3434         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3435                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3436                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3437                 if (prefetch_ios)
3438                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3439                                               prefetch_ios);
3440                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3441                                             prefetch_ios);
3442                 if (group >= elr->lr_next_group) {
3443                         ret = 1;
3444                         if (elr->lr_first_not_zeroed != ngroups &&
3445                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3446                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3447                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3448                                 ret = 0;
3449                         }
3450                 }
3451                 return ret;
3452         }
3453
3454         for (; group < ngroups; group++) {
3455                 gdp = ext4_get_group_desc(sb, group, NULL);
3456                 if (!gdp) {
3457                         ret = 1;
3458                         break;
3459                 }
3460
3461                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3462                         break;
3463         }
3464
3465         if (group >= ngroups)
3466                 ret = 1;
3467
3468         if (!ret) {
3469                 timeout = jiffies;
3470                 ret = ext4_init_inode_table(sb, group,
3471                                             elr->lr_timeout ? 0 : 1);
3472                 trace_ext4_lazy_itable_init(sb, group);
3473                 if (elr->lr_timeout == 0) {
3474                         timeout = (jiffies - timeout) *
3475                                 EXT4_SB(elr->lr_super)->s_li_wait_mult;
3476                         elr->lr_timeout = timeout;
3477                 }
3478                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3479                 elr->lr_next_group = group + 1;
3480         }
3481         return ret;
3482 }
3483
3484 /*
3485  * Remove lr_request from the list_request and free the
3486  * request structure. Should be called with li_list_mtx held
3487  */
3488 static void ext4_remove_li_request(struct ext4_li_request *elr)
3489 {
3490         if (!elr)
3491                 return;
3492
3493         list_del(&elr->lr_request);
3494         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3495         kfree(elr);
3496 }
3497
3498 static void ext4_unregister_li_request(struct super_block *sb)
3499 {
3500         mutex_lock(&ext4_li_mtx);
3501         if (!ext4_li_info) {
3502                 mutex_unlock(&ext4_li_mtx);
3503                 return;
3504         }
3505
3506         mutex_lock(&ext4_li_info->li_list_mtx);
3507         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3508         mutex_unlock(&ext4_li_info->li_list_mtx);
3509         mutex_unlock(&ext4_li_mtx);
3510 }
3511
3512 static struct task_struct *ext4_lazyinit_task;
3513
3514 /*
3515  * This is the function where ext4lazyinit thread lives. It walks
3516  * through the request list searching for next scheduled filesystem.
3517  * When such a fs is found, run the lazy initialization request
3518  * (ext4_rn_li_request) and keep track of the time spend in this
3519  * function. Based on that time we compute next schedule time of
3520  * the request. When walking through the list is complete, compute
3521  * next waking time and put itself into sleep.
3522  */
3523 static int ext4_lazyinit_thread(void *arg)
3524 {
3525         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3526         struct list_head *pos, *n;
3527         struct ext4_li_request *elr;
3528         unsigned long next_wakeup, cur;
3529
3530         BUG_ON(NULL == eli);
3531
3532 cont_thread:
3533         while (true) {
3534                 next_wakeup = MAX_JIFFY_OFFSET;
3535
3536                 mutex_lock(&eli->li_list_mtx);
3537                 if (list_empty(&eli->li_request_list)) {
3538                         mutex_unlock(&eli->li_list_mtx);
3539                         goto exit_thread;
3540                 }
3541                 list_for_each_safe(pos, n, &eli->li_request_list) {
3542                         int err = 0;
3543                         int progress = 0;
3544                         elr = list_entry(pos, struct ext4_li_request,
3545                                          lr_request);
3546
3547                         if (time_before(jiffies, elr->lr_next_sched)) {
3548                                 if (time_before(elr->lr_next_sched, next_wakeup))
3549                                         next_wakeup = elr->lr_next_sched;
3550                                 continue;
3551                         }
3552                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3553                                 if (sb_start_write_trylock(elr->lr_super)) {
3554                                         progress = 1;
3555                                         /*
3556                                          * We hold sb->s_umount, sb can not
3557                                          * be removed from the list, it is
3558                                          * now safe to drop li_list_mtx
3559                                          */
3560                                         mutex_unlock(&eli->li_list_mtx);
3561                                         err = ext4_run_li_request(elr);
3562                                         sb_end_write(elr->lr_super);
3563                                         mutex_lock(&eli->li_list_mtx);
3564                                         n = pos->next;
3565                                 }
3566                                 up_read((&elr->lr_super->s_umount));
3567                         }
3568                         /* error, remove the lazy_init job */
3569                         if (err) {
3570                                 ext4_remove_li_request(elr);
3571                                 continue;
3572                         }
3573                         if (!progress) {
3574                                 elr->lr_next_sched = jiffies +
3575                                         (prandom_u32()
3576                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3577                         }
3578                         if (time_before(elr->lr_next_sched, next_wakeup))
3579                                 next_wakeup = elr->lr_next_sched;
3580                 }
3581                 mutex_unlock(&eli->li_list_mtx);
3582
3583                 try_to_freeze();
3584
3585                 cur = jiffies;
3586                 if ((time_after_eq(cur, next_wakeup)) ||
3587                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3588                         cond_resched();
3589                         continue;
3590                 }
3591
3592                 schedule_timeout_interruptible(next_wakeup - cur);
3593
3594                 if (kthread_should_stop()) {
3595                         ext4_clear_request_list();
3596                         goto exit_thread;
3597                 }
3598         }
3599
3600 exit_thread:
3601         /*
3602          * It looks like the request list is empty, but we need
3603          * to check it under the li_list_mtx lock, to prevent any
3604          * additions into it, and of course we should lock ext4_li_mtx
3605          * to atomically free the list and ext4_li_info, because at
3606          * this point another ext4 filesystem could be registering
3607          * new one.
3608          */
3609         mutex_lock(&ext4_li_mtx);
3610         mutex_lock(&eli->li_list_mtx);
3611         if (!list_empty(&eli->li_request_list)) {
3612                 mutex_unlock(&eli->li_list_mtx);
3613                 mutex_unlock(&ext4_li_mtx);
3614                 goto cont_thread;
3615         }
3616         mutex_unlock(&eli->li_list_mtx);
3617         kfree(ext4_li_info);
3618         ext4_li_info = NULL;
3619         mutex_unlock(&ext4_li_mtx);
3620
3621         return 0;
3622 }
3623
3624 static void ext4_clear_request_list(void)
3625 {
3626         struct list_head *pos, *n;
3627         struct ext4_li_request *elr;
3628
3629         mutex_lock(&ext4_li_info->li_list_mtx);
3630         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3631                 elr = list_entry(pos, struct ext4_li_request,
3632                                  lr_request);
3633                 ext4_remove_li_request(elr);
3634         }
3635         mutex_unlock(&ext4_li_info->li_list_mtx);
3636 }
3637
3638 static int ext4_run_lazyinit_thread(void)
3639 {
3640         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3641                                          ext4_li_info, "ext4lazyinit");
3642         if (IS_ERR(ext4_lazyinit_task)) {
3643                 int err = PTR_ERR(ext4_lazyinit_task);
3644                 ext4_clear_request_list();
3645                 kfree(ext4_li_info);
3646                 ext4_li_info = NULL;
3647                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3648                                  "initialization thread\n",
3649                                  err);
3650                 return err;
3651         }
3652         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3653         return 0;
3654 }
3655
3656 /*
3657  * Check whether it make sense to run itable init. thread or not.
3658  * If there is at least one uninitialized inode table, return
3659  * corresponding group number, else the loop goes through all
3660  * groups and return total number of groups.
3661  */
3662 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3663 {
3664         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3665         struct ext4_group_desc *gdp = NULL;
3666
3667         if (!ext4_has_group_desc_csum(sb))
3668                 return ngroups;
3669
3670         for (group = 0; group < ngroups; group++) {
3671                 gdp = ext4_get_group_desc(sb, group, NULL);
3672                 if (!gdp)
3673                         continue;
3674
3675                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3676                         break;
3677         }
3678
3679         return group;
3680 }
3681
3682 static int ext4_li_info_new(void)
3683 {
3684         struct ext4_lazy_init *eli = NULL;
3685
3686         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3687         if (!eli)
3688                 return -ENOMEM;
3689
3690         INIT_LIST_HEAD(&eli->li_request_list);
3691         mutex_init(&eli->li_list_mtx);
3692
3693         eli->li_state |= EXT4_LAZYINIT_QUIT;
3694
3695         ext4_li_info = eli;
3696
3697         return 0;
3698 }
3699
3700 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3701                                             ext4_group_t start)
3702 {
3703         struct ext4_li_request *elr;
3704
3705         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3706         if (!elr)
3707                 return NULL;
3708
3709         elr->lr_super = sb;
3710         elr->lr_first_not_zeroed = start;
3711         if (test_opt(sb, PREFETCH_BLOCK_BITMAPS))
3712                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3713         else {
3714                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3715                 elr->lr_next_group = start;
3716         }
3717
3718         /*
3719          * Randomize first schedule time of the request to
3720          * spread the inode table initialization requests
3721          * better.
3722          */
3723         elr->lr_next_sched = jiffies + (prandom_u32() %
3724                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3725         return elr;
3726 }
3727
3728 int ext4_register_li_request(struct super_block *sb,
3729                              ext4_group_t first_not_zeroed)
3730 {
3731         struct ext4_sb_info *sbi = EXT4_SB(sb);
3732         struct ext4_li_request *elr = NULL;
3733         ext4_group_t ngroups = sbi->s_groups_count;
3734         int ret = 0;
3735
3736         mutex_lock(&ext4_li_mtx);
3737         if (sbi->s_li_request != NULL) {
3738                 /*
3739                  * Reset timeout so it can be computed again, because
3740                  * s_li_wait_mult might have changed.
3741                  */
3742                 sbi->s_li_request->lr_timeout = 0;
3743                 goto out;
3744         }
3745
3746         if (!test_opt(sb, PREFETCH_BLOCK_BITMAPS) &&
3747             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3748              !test_opt(sb, INIT_INODE_TABLE)))
3749                 goto out;
3750
3751         elr = ext4_li_request_new(sb, first_not_zeroed);
3752         if (!elr) {
3753                 ret = -ENOMEM;
3754                 goto out;
3755         }
3756
3757         if (NULL == ext4_li_info) {
3758                 ret = ext4_li_info_new();
3759                 if (ret)
3760                         goto out;
3761         }
3762
3763         mutex_lock(&ext4_li_info->li_list_mtx);
3764         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3765         mutex_unlock(&ext4_li_info->li_list_mtx);
3766
3767         sbi->s_li_request = elr;
3768         /*
3769          * set elr to NULL here since it has been inserted to
3770          * the request_list and the removal and free of it is
3771          * handled by ext4_clear_request_list from now on.
3772          */
3773         elr = NULL;
3774
3775         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3776                 ret = ext4_run_lazyinit_thread();
3777                 if (ret)
3778                         goto out;
3779         }
3780 out:
3781         mutex_unlock(&ext4_li_mtx);
3782         if (ret)
3783                 kfree(elr);
3784         return ret;
3785 }
3786
3787 /*
3788  * We do not need to lock anything since this is called on
3789  * module unload.
3790  */
3791 static void ext4_destroy_lazyinit_thread(void)
3792 {
3793         /*
3794          * If thread exited earlier
3795          * there's nothing to be done.
3796          */
3797         if (!ext4_li_info || !ext4_lazyinit_task)
3798                 return;
3799
3800         kthread_stop(ext4_lazyinit_task);
3801 }
3802
3803 static int set_journal_csum_feature_set(struct super_block *sb)
3804 {
3805         int ret = 1;
3806         int compat, incompat;
3807         struct ext4_sb_info *sbi = EXT4_SB(sb);
3808
3809         if (ext4_has_metadata_csum(sb)) {
3810                 /* journal checksum v3 */
3811                 compat = 0;
3812                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3813         } else {
3814                 /* journal checksum v1 */
3815                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3816                 incompat = 0;
3817         }
3818
3819         jbd2_journal_clear_features(sbi->s_journal,
3820                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3821                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3822                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3823         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3824                 ret = jbd2_journal_set_features(sbi->s_journal,
3825                                 compat, 0,
3826                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3827                                 incompat);
3828         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3829                 ret = jbd2_journal_set_features(sbi->s_journal,
3830                                 compat, 0,
3831                                 incompat);
3832                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3833                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3834         } else {
3835                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3836                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3837         }
3838
3839         return ret;
3840 }
3841
3842 /*
3843  * Note: calculating the overhead so we can be compatible with
3844  * historical BSD practice is quite difficult in the face of
3845  * clusters/bigalloc.  This is because multiple metadata blocks from
3846  * different block group can end up in the same allocation cluster.
3847  * Calculating the exact overhead in the face of clustered allocation
3848  * requires either O(all block bitmaps) in memory or O(number of block
3849  * groups**2) in time.  We will still calculate the superblock for
3850  * older file systems --- and if we come across with a bigalloc file
3851  * system with zero in s_overhead_clusters the estimate will be close to
3852  * correct especially for very large cluster sizes --- but for newer
3853  * file systems, it's better to calculate this figure once at mkfs
3854  * time, and store it in the superblock.  If the superblock value is
3855  * present (even for non-bigalloc file systems), we will use it.
3856  */
3857 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3858                           char *buf)
3859 {
3860         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3861         struct ext4_group_desc  *gdp;
3862         ext4_fsblk_t            first_block, last_block, b;
3863         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3864         int                     s, j, count = 0;
3865
3866         if (!ext4_has_feature_bigalloc(sb))
3867                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3868                         sbi->s_itb_per_group + 2);
3869
3870         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3871                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3872         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3873         for (i = 0; i < ngroups; i++) {
3874                 gdp = ext4_get_group_desc(sb, i, NULL);
3875                 b = ext4_block_bitmap(sb, gdp);
3876                 if (b >= first_block && b <= last_block) {
3877                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3878                         count++;
3879                 }
3880                 b = ext4_inode_bitmap(sb, gdp);
3881                 if (b >= first_block && b <= last_block) {
3882                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3883                         count++;
3884                 }
3885                 b = ext4_inode_table(sb, gdp);
3886                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3887                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3888                                 int c = EXT4_B2C(sbi, b - first_block);
3889                                 ext4_set_bit(c, buf);
3890                                 count++;
3891                         }
3892                 if (i != grp)
3893                         continue;
3894                 s = 0;
3895                 if (ext4_bg_has_super(sb, grp)) {
3896                         ext4_set_bit(s++, buf);
3897                         count++;
3898                 }
3899                 j = ext4_bg_num_gdb(sb, grp);
3900                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3901                         ext4_error(sb, "Invalid number of block group "
3902                                    "descriptor blocks: %d", j);
3903                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3904                 }
3905                 count += j;
3906                 for (; j > 0; j--)
3907                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3908         }
3909         if (!count)
3910                 return 0;
3911         return EXT4_CLUSTERS_PER_GROUP(sb) -
3912                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3913 }
3914
3915 /*
3916  * Compute the overhead and stash it in sbi->s_overhead
3917  */
3918 int ext4_calculate_overhead(struct super_block *sb)
3919 {
3920         struct ext4_sb_info *sbi = EXT4_SB(sb);
3921         struct ext4_super_block *es = sbi->s_es;
3922         struct inode *j_inode;
3923         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3924         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3925         ext4_fsblk_t overhead = 0;
3926         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3927
3928         if (!buf)
3929                 return -ENOMEM;
3930
3931         /*
3932          * Compute the overhead (FS structures).  This is constant
3933          * for a given filesystem unless the number of block groups
3934          * changes so we cache the previous value until it does.
3935          */
3936
3937         /*
3938          * All of the blocks before first_data_block are overhead
3939          */
3940         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3941
3942         /*
3943          * Add the overhead found in each block group
3944          */
3945         for (i = 0; i < ngroups; i++) {
3946                 int blks;
3947
3948                 blks = count_overhead(sb, i, buf);
3949                 overhead += blks;
3950                 if (blks)
3951                         memset(buf, 0, PAGE_SIZE);
3952                 cond_resched();
3953         }
3954
3955         /*
3956          * Add the internal journal blocks whether the journal has been
3957          * loaded or not
3958          */
3959         if (sbi->s_journal && !sbi->s_journal_bdev)
3960                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
3961         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3962                 /* j_inum for internal journal is non-zero */
3963                 j_inode = ext4_get_journal_inode(sb, j_inum);
3964                 if (j_inode) {
3965                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3966                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3967                         iput(j_inode);
3968                 } else {
3969                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3970                 }
3971         }
3972         sbi->s_overhead = overhead;
3973         smp_wmb();
3974         free_page((unsigned long) buf);
3975         return 0;
3976 }
3977
3978 static void ext4_set_resv_clusters(struct super_block *sb)
3979 {
3980         ext4_fsblk_t resv_clusters;
3981         struct ext4_sb_info *sbi = EXT4_SB(sb);
3982
3983         /*
3984          * There's no need to reserve anything when we aren't using extents.
3985          * The space estimates are exact, there are no unwritten extents,
3986          * hole punching doesn't need new metadata... This is needed especially
3987          * to keep ext2/3 backward compatibility.
3988          */
3989         if (!ext4_has_feature_extents(sb))
3990                 return;
3991         /*
3992          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3993          * This should cover the situations where we can not afford to run
3994          * out of space like for example punch hole, or converting
3995          * unwritten extents in delalloc path. In most cases such
3996          * allocation would require 1, or 2 blocks, higher numbers are
3997          * very rare.
3998          */
3999         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4000                          sbi->s_cluster_bits);
4001
4002         do_div(resv_clusters, 50);
4003         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4004
4005         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4006 }
4007
4008 static const char *ext4_quota_mode(struct super_block *sb)
4009 {
4010 #ifdef CONFIG_QUOTA
4011         if (!ext4_quota_capable(sb))
4012                 return "none";
4013
4014         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4015                 return "journalled";
4016         else
4017                 return "writeback";
4018 #else
4019         return "disabled";
4020 #endif
4021 }
4022
4023 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
4024 {
4025         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
4026         char *orig_data = kstrdup(data, GFP_KERNEL);
4027         struct buffer_head *bh, **group_desc;
4028         struct ext4_super_block *es = NULL;
4029         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4030         struct flex_groups **flex_groups;
4031         ext4_fsblk_t block;
4032         ext4_fsblk_t sb_block = get_sb_block(&data);
4033         ext4_fsblk_t logical_sb_block;
4034         unsigned long offset = 0;
4035         unsigned long journal_devnum = 0;
4036         unsigned long def_mount_opts;
4037         struct inode *root;
4038         const char *descr;
4039         int ret = -ENOMEM;
4040         int blocksize, clustersize;
4041         unsigned int db_count;
4042         unsigned int i;
4043         int needs_recovery, has_huge_files;
4044         __u64 blocks_count;
4045         int err = 0;
4046         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4047         ext4_group_t first_not_zeroed;
4048
4049         if ((data && !orig_data) || !sbi)
4050                 goto out_free_base;
4051
4052         sbi->s_daxdev = dax_dev;
4053         sbi->s_blockgroup_lock =
4054                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4055         if (!sbi->s_blockgroup_lock)
4056                 goto out_free_base;
4057
4058         sb->s_fs_info = sbi;
4059         sbi->s_sb = sb;
4060         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
4061         sbi->s_sb_block = sb_block;
4062         if (sb->s_bdev->bd_part)
4063                 sbi->s_sectors_written_start =
4064                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
4065
4066         /* Cleanup superblock name */
4067         strreplace(sb->s_id, '/', '!');
4068
4069         /* -EINVAL is default */
4070         ret = -EINVAL;
4071         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4072         if (!blocksize) {
4073                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4074                 goto out_fail;
4075         }
4076
4077         /*
4078          * The ext4 superblock will not be buffer aligned for other than 1kB
4079          * block sizes.  We need to calculate the offset from buffer start.
4080          */
4081         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4082                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4083                 offset = do_div(logical_sb_block, blocksize);
4084         } else {
4085                 logical_sb_block = sb_block;
4086         }
4087
4088         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4089         if (IS_ERR(bh)) {
4090                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4091                 ret = PTR_ERR(bh);
4092                 goto out_fail;
4093         }
4094         /*
4095          * Note: s_es must be initialized as soon as possible because
4096          *       some ext4 macro-instructions depend on its value
4097          */
4098         es = (struct ext4_super_block *) (bh->b_data + offset);
4099         sbi->s_es = es;
4100         sb->s_magic = le16_to_cpu(es->s_magic);
4101         if (sb->s_magic != EXT4_SUPER_MAGIC)
4102                 goto cantfind_ext4;
4103         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
4104
4105         /* Warn if metadata_csum and gdt_csum are both set. */
4106         if (ext4_has_feature_metadata_csum(sb) &&
4107             ext4_has_feature_gdt_csum(sb))
4108                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4109                              "redundant flags; please run fsck.");
4110
4111         /* Check for a known checksum algorithm */
4112         if (!ext4_verify_csum_type(sb, es)) {
4113                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4114                          "unknown checksum algorithm.");
4115                 silent = 1;
4116                 goto cantfind_ext4;
4117         }
4118
4119         /* Load the checksum driver */
4120         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4121         if (IS_ERR(sbi->s_chksum_driver)) {
4122                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4123                 ret = PTR_ERR(sbi->s_chksum_driver);
4124                 sbi->s_chksum_driver = NULL;
4125                 goto failed_mount;
4126         }
4127
4128         /* Check superblock checksum */
4129         if (!ext4_superblock_csum_verify(sb, es)) {
4130                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4131                          "invalid superblock checksum.  Run e2fsck?");
4132                 silent = 1;
4133                 ret = -EFSBADCRC;
4134                 goto cantfind_ext4;
4135         }
4136
4137         /* Precompute checksum seed for all metadata */
4138         if (ext4_has_feature_csum_seed(sb))
4139                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4140         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4141                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4142                                                sizeof(es->s_uuid));
4143
4144         /* Set defaults before we parse the mount options */
4145         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4146         set_opt(sb, INIT_INODE_TABLE);
4147         if (def_mount_opts & EXT4_DEFM_DEBUG)
4148                 set_opt(sb, DEBUG);
4149         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4150                 set_opt(sb, GRPID);
4151         if (def_mount_opts & EXT4_DEFM_UID16)
4152                 set_opt(sb, NO_UID32);
4153         /* xattr user namespace & acls are now defaulted on */
4154         set_opt(sb, XATTR_USER);
4155 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4156         set_opt(sb, POSIX_ACL);
4157 #endif
4158         if (ext4_has_feature_fast_commit(sb))
4159                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4160         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4161         if (ext4_has_metadata_csum(sb))
4162                 set_opt(sb, JOURNAL_CHECKSUM);
4163
4164         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4165                 set_opt(sb, JOURNAL_DATA);
4166         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4167                 set_opt(sb, ORDERED_DATA);
4168         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4169                 set_opt(sb, WRITEBACK_DATA);
4170
4171         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4172                 set_opt(sb, ERRORS_PANIC);
4173         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4174                 set_opt(sb, ERRORS_CONT);
4175         else
4176                 set_opt(sb, ERRORS_RO);
4177         /* block_validity enabled by default; disable with noblock_validity */
4178         set_opt(sb, BLOCK_VALIDITY);
4179         if (def_mount_opts & EXT4_DEFM_DISCARD)
4180                 set_opt(sb, DISCARD);
4181
4182         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4183         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4184         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4185         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4186         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4187
4188         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4189                 set_opt(sb, BARRIER);
4190
4191         /*
4192          * enable delayed allocation by default
4193          * Use -o nodelalloc to turn it off
4194          */
4195         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4196             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4197                 set_opt(sb, DELALLOC);
4198
4199         /*
4200          * set default s_li_wait_mult for lazyinit, for the case there is
4201          * no mount option specified.
4202          */
4203         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4204
4205         if (le32_to_cpu(es->s_log_block_size) >
4206             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4207                 ext4_msg(sb, KERN_ERR,
4208                          "Invalid log block size: %u",
4209                          le32_to_cpu(es->s_log_block_size));
4210                 goto failed_mount;
4211         }
4212         if (le32_to_cpu(es->s_log_cluster_size) >
4213             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4214                 ext4_msg(sb, KERN_ERR,
4215                          "Invalid log cluster size: %u",
4216                          le32_to_cpu(es->s_log_cluster_size));
4217                 goto failed_mount;
4218         }
4219
4220         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4221
4222         if (blocksize == PAGE_SIZE)
4223                 set_opt(sb, DIOREAD_NOLOCK);
4224
4225         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4226                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4227                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4228         } else {
4229                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4230                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4231                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4232                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4233                                  sbi->s_first_ino);
4234                         goto failed_mount;
4235                 }
4236                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4237                     (!is_power_of_2(sbi->s_inode_size)) ||
4238                     (sbi->s_inode_size > blocksize)) {
4239                         ext4_msg(sb, KERN_ERR,
4240                                "unsupported inode size: %d",
4241                                sbi->s_inode_size);
4242                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4243                         goto failed_mount;
4244                 }
4245                 /*
4246                  * i_atime_extra is the last extra field available for
4247                  * [acm]times in struct ext4_inode. Checking for that
4248                  * field should suffice to ensure we have extra space
4249                  * for all three.
4250                  */
4251                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4252                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4253                         sb->s_time_gran = 1;
4254                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4255                 } else {
4256                         sb->s_time_gran = NSEC_PER_SEC;
4257                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4258                 }
4259                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4260         }
4261         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4262                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4263                         EXT4_GOOD_OLD_INODE_SIZE;
4264                 if (ext4_has_feature_extra_isize(sb)) {
4265                         unsigned v, max = (sbi->s_inode_size -
4266                                            EXT4_GOOD_OLD_INODE_SIZE);
4267
4268                         v = le16_to_cpu(es->s_want_extra_isize);
4269                         if (v > max) {
4270                                 ext4_msg(sb, KERN_ERR,
4271                                          "bad s_want_extra_isize: %d", v);
4272                                 goto failed_mount;
4273                         }
4274                         if (sbi->s_want_extra_isize < v)
4275                                 sbi->s_want_extra_isize = v;
4276
4277                         v = le16_to_cpu(es->s_min_extra_isize);
4278                         if (v > max) {
4279                                 ext4_msg(sb, KERN_ERR,
4280                                          "bad s_min_extra_isize: %d", v);
4281                                 goto failed_mount;
4282                         }
4283                         if (sbi->s_want_extra_isize < v)
4284                                 sbi->s_want_extra_isize = v;
4285                 }
4286         }
4287
4288         if (sbi->s_es->s_mount_opts[0]) {
4289                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4290                                               sizeof(sbi->s_es->s_mount_opts),
4291                                               GFP_KERNEL);
4292                 if (!s_mount_opts)
4293                         goto failed_mount;
4294                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
4295                                    &journal_ioprio, 0)) {
4296                         ext4_msg(sb, KERN_WARNING,
4297                                  "failed to parse options in superblock: %s",
4298                                  s_mount_opts);
4299                 }
4300                 kfree(s_mount_opts);
4301         }
4302         sbi->s_def_mount_opt = sbi->s_mount_opt;
4303         if (!parse_options((char *) data, sb, &journal_devnum,
4304                            &journal_ioprio, 0))
4305                 goto failed_mount;
4306
4307 #ifdef CONFIG_UNICODE
4308         if (ext4_has_feature_casefold(sb) && !sb->s_encoding) {
4309                 const struct ext4_sb_encodings *encoding_info;
4310                 struct unicode_map *encoding;
4311                 __u16 encoding_flags;
4312
4313                 if (ext4_has_feature_encrypt(sb)) {
4314                         ext4_msg(sb, KERN_ERR,
4315                                  "Can't mount with encoding and encryption");
4316                         goto failed_mount;
4317                 }
4318
4319                 if (ext4_sb_read_encoding(es, &encoding_info,
4320                                           &encoding_flags)) {
4321                         ext4_msg(sb, KERN_ERR,
4322                                  "Encoding requested by superblock is unknown");
4323                         goto failed_mount;
4324                 }
4325
4326                 encoding = utf8_load(encoding_info->version);
4327                 if (IS_ERR(encoding)) {
4328                         ext4_msg(sb, KERN_ERR,
4329                                  "can't mount with superblock charset: %s-%s "
4330                                  "not supported by the kernel. flags: 0x%x.",
4331                                  encoding_info->name, encoding_info->version,
4332                                  encoding_flags);
4333                         goto failed_mount;
4334                 }
4335                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4336                          "%s-%s with flags 0x%hx", encoding_info->name,
4337                          encoding_info->version?:"\b", encoding_flags);
4338
4339                 sb->s_encoding = encoding;
4340                 sb->s_encoding_flags = encoding_flags;
4341         }
4342 #endif
4343
4344         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4345                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!\n");
4346                 /* can't mount with both data=journal and dioread_nolock. */
4347                 clear_opt(sb, DIOREAD_NOLOCK);
4348                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4349                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4350                         ext4_msg(sb, KERN_ERR, "can't mount with "
4351                                  "both data=journal and delalloc");
4352                         goto failed_mount;
4353                 }
4354                 if (test_opt(sb, DAX_ALWAYS)) {
4355                         ext4_msg(sb, KERN_ERR, "can't mount with "
4356                                  "both data=journal and dax");
4357                         goto failed_mount;
4358                 }
4359                 if (ext4_has_feature_encrypt(sb)) {
4360                         ext4_msg(sb, KERN_WARNING,
4361                                  "encrypted files will use data=ordered "
4362                                  "instead of data journaling mode");
4363                 }
4364                 if (test_opt(sb, DELALLOC))
4365                         clear_opt(sb, DELALLOC);
4366         } else {
4367                 sb->s_iflags |= SB_I_CGROUPWB;
4368         }
4369
4370         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4371                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4372
4373         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4374             (ext4_has_compat_features(sb) ||
4375              ext4_has_ro_compat_features(sb) ||
4376              ext4_has_incompat_features(sb)))
4377                 ext4_msg(sb, KERN_WARNING,
4378                        "feature flags set on rev 0 fs, "
4379                        "running e2fsck is recommended");
4380
4381         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4382                 set_opt2(sb, HURD_COMPAT);
4383                 if (ext4_has_feature_64bit(sb)) {
4384                         ext4_msg(sb, KERN_ERR,
4385                                  "The Hurd can't support 64-bit file systems");
4386                         goto failed_mount;
4387                 }
4388
4389                 /*
4390                  * ea_inode feature uses l_i_version field which is not
4391                  * available in HURD_COMPAT mode.
4392                  */
4393                 if (ext4_has_feature_ea_inode(sb)) {
4394                         ext4_msg(sb, KERN_ERR,
4395                                  "ea_inode feature is not supported for Hurd");
4396                         goto failed_mount;
4397                 }
4398         }
4399
4400         if (IS_EXT2_SB(sb)) {
4401                 if (ext2_feature_set_ok(sb))
4402                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4403                                  "using the ext4 subsystem");
4404                 else {
4405                         /*
4406                          * If we're probing be silent, if this looks like
4407                          * it's actually an ext[34] filesystem.
4408                          */
4409                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4410                                 goto failed_mount;
4411                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4412                                  "to feature incompatibilities");
4413                         goto failed_mount;
4414                 }
4415         }
4416
4417         if (IS_EXT3_SB(sb)) {
4418                 if (ext3_feature_set_ok(sb))
4419                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4420                                  "using the ext4 subsystem");
4421                 else {
4422                         /*
4423                          * If we're probing be silent, if this looks like
4424                          * it's actually an ext4 filesystem.
4425                          */
4426                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4427                                 goto failed_mount;
4428                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4429                                  "to feature incompatibilities");
4430                         goto failed_mount;
4431                 }
4432         }
4433
4434         /*
4435          * Check feature flags regardless of the revision level, since we
4436          * previously didn't change the revision level when setting the flags,
4437          * so there is a chance incompat flags are set on a rev 0 filesystem.
4438          */
4439         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4440                 goto failed_mount;
4441
4442         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4443                 ext4_msg(sb, KERN_ERR,
4444                          "Number of reserved GDT blocks insanely large: %d",
4445                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4446                 goto failed_mount;
4447         }
4448
4449         if (bdev_dax_supported(sb->s_bdev, blocksize))
4450                 set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4451
4452         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4453                 if (ext4_has_feature_inline_data(sb)) {
4454                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4455                                         " that may contain inline data");
4456                         goto failed_mount;
4457                 }
4458                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4459                         ext4_msg(sb, KERN_ERR,
4460                                 "DAX unsupported by block device.");
4461                         goto failed_mount;
4462                 }
4463         }
4464
4465         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4466                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4467                          es->s_encryption_level);
4468                 goto failed_mount;
4469         }
4470
4471         if (sb->s_blocksize != blocksize) {
4472                 /* Validate the filesystem blocksize */
4473                 if (!sb_set_blocksize(sb, blocksize)) {
4474                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4475                                         blocksize);
4476                         goto failed_mount;
4477                 }
4478
4479                 brelse(bh);
4480                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4481                 offset = do_div(logical_sb_block, blocksize);
4482                 bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4483                 if (IS_ERR(bh)) {
4484                         ext4_msg(sb, KERN_ERR,
4485                                "Can't read superblock on 2nd try");
4486                         ret = PTR_ERR(bh);
4487                         bh = NULL;
4488                         goto failed_mount;
4489                 }
4490                 es = (struct ext4_super_block *)(bh->b_data + offset);
4491                 sbi->s_es = es;
4492                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4493                         ext4_msg(sb, KERN_ERR,
4494                                "Magic mismatch, very weird!");
4495                         goto failed_mount;
4496                 }
4497         }
4498
4499         has_huge_files = ext4_has_feature_huge_file(sb);
4500         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4501                                                       has_huge_files);
4502         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4503
4504         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4505         if (ext4_has_feature_64bit(sb)) {
4506                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4507                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4508                     !is_power_of_2(sbi->s_desc_size)) {
4509                         ext4_msg(sb, KERN_ERR,
4510                                "unsupported descriptor size %lu",
4511                                sbi->s_desc_size);
4512                         goto failed_mount;
4513                 }
4514         } else
4515                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4516
4517         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4518         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4519
4520         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4521         if (sbi->s_inodes_per_block == 0)
4522                 goto cantfind_ext4;
4523         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4524             sbi->s_inodes_per_group > blocksize * 8) {
4525                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4526                          sbi->s_inodes_per_group);
4527                 goto failed_mount;
4528         }
4529         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4530                                         sbi->s_inodes_per_block;
4531         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4532         sbi->s_sbh = bh;
4533         sbi->s_mount_state = le16_to_cpu(es->s_state);
4534         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4535         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4536
4537         for (i = 0; i < 4; i++)
4538                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4539         sbi->s_def_hash_version = es->s_def_hash_version;
4540         if (ext4_has_feature_dir_index(sb)) {
4541                 i = le32_to_cpu(es->s_flags);
4542                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4543                         sbi->s_hash_unsigned = 3;
4544                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4545 #ifdef __CHAR_UNSIGNED__
4546                         if (!sb_rdonly(sb))
4547                                 es->s_flags |=
4548                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4549                         sbi->s_hash_unsigned = 3;
4550 #else
4551                         if (!sb_rdonly(sb))
4552                                 es->s_flags |=
4553                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4554 #endif
4555                 }
4556         }
4557
4558         /* Handle clustersize */
4559         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4560         if (ext4_has_feature_bigalloc(sb)) {
4561                 if (clustersize < blocksize) {
4562                         ext4_msg(sb, KERN_ERR,
4563                                  "cluster size (%d) smaller than "
4564                                  "block size (%d)", clustersize, blocksize);
4565                         goto failed_mount;
4566                 }
4567                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4568                         le32_to_cpu(es->s_log_block_size);
4569                 sbi->s_clusters_per_group =
4570                         le32_to_cpu(es->s_clusters_per_group);
4571                 if (sbi->s_clusters_per_group > blocksize * 8) {
4572                         ext4_msg(sb, KERN_ERR,
4573                                  "#clusters per group too big: %lu",
4574                                  sbi->s_clusters_per_group);
4575                         goto failed_mount;
4576                 }
4577                 if (sbi->s_blocks_per_group !=
4578                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4579                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4580                                  "clusters per group (%lu) inconsistent",
4581                                  sbi->s_blocks_per_group,
4582                                  sbi->s_clusters_per_group);
4583                         goto failed_mount;
4584                 }
4585         } else {
4586                 if (clustersize != blocksize) {
4587                         ext4_msg(sb, KERN_ERR,
4588                                  "fragment/cluster size (%d) != "
4589                                  "block size (%d)", clustersize, blocksize);
4590                         goto failed_mount;
4591                 }
4592                 if (sbi->s_blocks_per_group > blocksize * 8) {
4593                         ext4_msg(sb, KERN_ERR,
4594                                  "#blocks per group too big: %lu",
4595                                  sbi->s_blocks_per_group);
4596                         goto failed_mount;
4597                 }
4598                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4599                 sbi->s_cluster_bits = 0;
4600         }
4601         sbi->s_cluster_ratio = clustersize / blocksize;
4602
4603         /* Do we have standard group size of clustersize * 8 blocks ? */
4604         if (sbi->s_blocks_per_group == clustersize << 3)
4605                 set_opt2(sb, STD_GROUP_SIZE);
4606
4607         /*
4608          * Test whether we have more sectors than will fit in sector_t,
4609          * and whether the max offset is addressable by the page cache.
4610          */
4611         err = generic_check_addressable(sb->s_blocksize_bits,
4612                                         ext4_blocks_count(es));
4613         if (err) {
4614                 ext4_msg(sb, KERN_ERR, "filesystem"
4615                          " too large to mount safely on this system");
4616                 goto failed_mount;
4617         }
4618
4619         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4620                 goto cantfind_ext4;
4621
4622         /* check blocks count against device size */
4623         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4624         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4625                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4626                        "exceeds size of device (%llu blocks)",
4627                        ext4_blocks_count(es), blocks_count);
4628                 goto failed_mount;
4629         }
4630
4631         /*
4632          * It makes no sense for the first data block to be beyond the end
4633          * of the filesystem.
4634          */
4635         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4636                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4637                          "block %u is beyond end of filesystem (%llu)",
4638                          le32_to_cpu(es->s_first_data_block),
4639                          ext4_blocks_count(es));
4640                 goto failed_mount;
4641         }
4642         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4643             (sbi->s_cluster_ratio == 1)) {
4644                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4645                          "block is 0 with a 1k block and cluster size");
4646                 goto failed_mount;
4647         }
4648
4649         blocks_count = (ext4_blocks_count(es) -
4650                         le32_to_cpu(es->s_first_data_block) +
4651                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4652         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4653         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4654                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4655                        "(block count %llu, first data block %u, "
4656                        "blocks per group %lu)", blocks_count,
4657                        ext4_blocks_count(es),
4658                        le32_to_cpu(es->s_first_data_block),
4659                        EXT4_BLOCKS_PER_GROUP(sb));
4660                 goto failed_mount;
4661         }
4662         sbi->s_groups_count = blocks_count;
4663         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4664                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4665         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4666             le32_to_cpu(es->s_inodes_count)) {
4667                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4668                          le32_to_cpu(es->s_inodes_count),
4669                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4670                 ret = -EINVAL;
4671                 goto failed_mount;
4672         }
4673         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4674                    EXT4_DESC_PER_BLOCK(sb);
4675         if (ext4_has_feature_meta_bg(sb)) {
4676                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4677                         ext4_msg(sb, KERN_WARNING,
4678                                  "first meta block group too large: %u "
4679                                  "(group descriptor block count %u)",
4680                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4681                         goto failed_mount;
4682                 }
4683         }
4684         rcu_assign_pointer(sbi->s_group_desc,
4685                            kvmalloc_array(db_count,
4686                                           sizeof(struct buffer_head *),
4687                                           GFP_KERNEL));
4688         if (sbi->s_group_desc == NULL) {
4689                 ext4_msg(sb, KERN_ERR, "not enough memory");
4690                 ret = -ENOMEM;
4691                 goto failed_mount;
4692         }
4693
4694         bgl_lock_init(sbi->s_blockgroup_lock);
4695
4696         /* Pre-read the descriptors into the buffer cache */
4697         for (i = 0; i < db_count; i++) {
4698                 block = descriptor_loc(sb, logical_sb_block, i);
4699                 ext4_sb_breadahead_unmovable(sb, block);
4700         }
4701
4702         for (i = 0; i < db_count; i++) {
4703                 struct buffer_head *bh;
4704
4705                 block = descriptor_loc(sb, logical_sb_block, i);
4706                 bh = ext4_sb_bread_unmovable(sb, block);
4707                 if (IS_ERR(bh)) {
4708                         ext4_msg(sb, KERN_ERR,
4709                                "can't read group descriptor %d", i);
4710                         db_count = i;
4711                         ret = PTR_ERR(bh);
4712                         goto failed_mount2;
4713                 }
4714                 rcu_read_lock();
4715                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4716                 rcu_read_unlock();
4717         }
4718         sbi->s_gdb_count = db_count;
4719         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4720                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4721                 ret = -EFSCORRUPTED;
4722                 goto failed_mount2;
4723         }
4724
4725         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4726
4727         /* Register extent status tree shrinker */
4728         if (ext4_es_register_shrinker(sbi))
4729                 goto failed_mount3;
4730
4731         sbi->s_stripe = ext4_get_stripe_size(sbi);
4732         sbi->s_extent_max_zeroout_kb = 32;
4733
4734         /*
4735          * set up enough so that it can read an inode
4736          */
4737         sb->s_op = &ext4_sops;
4738         sb->s_export_op = &ext4_export_ops;
4739         sb->s_xattr = ext4_xattr_handlers;
4740 #ifdef CONFIG_FS_ENCRYPTION
4741         sb->s_cop = &ext4_cryptops;
4742 #endif
4743 #ifdef CONFIG_FS_VERITY
4744         sb->s_vop = &ext4_verityops;
4745 #endif
4746 #ifdef CONFIG_QUOTA
4747         sb->dq_op = &ext4_quota_operations;
4748         if (ext4_has_feature_quota(sb))
4749                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4750         else
4751                 sb->s_qcop = &ext4_qctl_operations;
4752         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4753 #endif
4754         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4755
4756         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4757         mutex_init(&sbi->s_orphan_lock);
4758
4759         /* Initialize fast commit stuff */
4760         atomic_set(&sbi->s_fc_subtid, 0);
4761         atomic_set(&sbi->s_fc_ineligible_updates, 0);
4762         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4763         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4764         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4765         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4766         sbi->s_fc_bytes = 0;
4767         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4768         ext4_clear_mount_flag(sb, EXT4_MF_FC_COMMITTING);
4769         spin_lock_init(&sbi->s_fc_lock);
4770         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4771         sbi->s_fc_replay_state.fc_regions = NULL;
4772         sbi->s_fc_replay_state.fc_regions_size = 0;
4773         sbi->s_fc_replay_state.fc_regions_used = 0;
4774         sbi->s_fc_replay_state.fc_regions_valid = 0;
4775         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4776         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4777         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4778
4779         sb->s_root = NULL;
4780
4781         needs_recovery = (es->s_last_orphan != 0 ||
4782                           ext4_has_feature_journal_needs_recovery(sb));
4783
4784         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4785                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4786                         goto failed_mount3a;
4787
4788         /*
4789          * The first inode we look at is the journal inode.  Don't try
4790          * root first: it may be modified in the journal!
4791          */
4792         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4793                 err = ext4_load_journal(sb, es, journal_devnum);
4794                 if (err)
4795                         goto failed_mount3a;
4796         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4797                    ext4_has_feature_journal_needs_recovery(sb)) {
4798                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4799                        "suppressed and not mounted read-only");
4800                 goto failed_mount_wq;
4801         } else {
4802                 /* Nojournal mode, all journal mount options are illegal */
4803                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4804                         ext4_msg(sb, KERN_ERR, "can't mount with "
4805                                  "journal_checksum, fs mounted w/o journal");
4806                         goto failed_mount_wq;
4807                 }
4808                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4809                         ext4_msg(sb, KERN_ERR, "can't mount with "
4810                                  "journal_async_commit, fs mounted w/o journal");
4811                         goto failed_mount_wq;
4812                 }
4813                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4814                         ext4_msg(sb, KERN_ERR, "can't mount with "
4815                                  "commit=%lu, fs mounted w/o journal",
4816                                  sbi->s_commit_interval / HZ);
4817                         goto failed_mount_wq;
4818                 }
4819                 if (EXT4_MOUNT_DATA_FLAGS &
4820                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4821                         ext4_msg(sb, KERN_ERR, "can't mount with "
4822                                  "data=, fs mounted w/o journal");
4823                         goto failed_mount_wq;
4824                 }
4825                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4826                 clear_opt(sb, JOURNAL_CHECKSUM);
4827                 clear_opt(sb, DATA_FLAGS);
4828                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4829                 sbi->s_journal = NULL;
4830                 needs_recovery = 0;
4831                 goto no_journal;
4832         }
4833
4834         if (ext4_has_feature_64bit(sb) &&
4835             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4836                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4837                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4838                 goto failed_mount_wq;
4839         }
4840
4841         if (!set_journal_csum_feature_set(sb)) {
4842                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4843                          "feature set");
4844                 goto failed_mount_wq;
4845         }
4846
4847         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4848                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4849                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4850                 ext4_msg(sb, KERN_ERR,
4851                         "Failed to set fast commit journal feature");
4852                 goto failed_mount_wq;
4853         }
4854
4855         /* We have now updated the journal if required, so we can
4856          * validate the data journaling mode. */
4857         switch (test_opt(sb, DATA_FLAGS)) {
4858         case 0:
4859                 /* No mode set, assume a default based on the journal
4860                  * capabilities: ORDERED_DATA if the journal can
4861                  * cope, else JOURNAL_DATA
4862                  */
4863                 if (jbd2_journal_check_available_features
4864                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4865                         set_opt(sb, ORDERED_DATA);
4866                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4867                 } else {
4868                         set_opt(sb, JOURNAL_DATA);
4869                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4870                 }
4871                 break;
4872
4873         case EXT4_MOUNT_ORDERED_DATA:
4874         case EXT4_MOUNT_WRITEBACK_DATA:
4875                 if (!jbd2_journal_check_available_features
4876                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4877                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4878                                "requested data journaling mode");
4879                         goto failed_mount_wq;
4880                 }
4881                 break;
4882         default:
4883                 break;
4884         }
4885
4886         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4887             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4888                 ext4_msg(sb, KERN_ERR, "can't mount with "
4889                         "journal_async_commit in data=ordered mode");
4890                 goto failed_mount_wq;
4891         }
4892
4893         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4894
4895         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4896         sbi->s_journal->j_submit_inode_data_buffers =
4897                 ext4_journal_submit_inode_data_buffers;
4898         sbi->s_journal->j_finish_inode_data_buffers =
4899                 ext4_journal_finish_inode_data_buffers;
4900
4901 no_journal:
4902         if (!test_opt(sb, NO_MBCACHE)) {
4903                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4904                 if (!sbi->s_ea_block_cache) {
4905                         ext4_msg(sb, KERN_ERR,
4906                                  "Failed to create ea_block_cache");
4907                         goto failed_mount_wq;
4908                 }
4909
4910                 if (ext4_has_feature_ea_inode(sb)) {
4911                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4912                         if (!sbi->s_ea_inode_cache) {
4913                                 ext4_msg(sb, KERN_ERR,
4914                                          "Failed to create ea_inode_cache");
4915                                 goto failed_mount_wq;
4916                         }
4917                 }
4918         }
4919
4920         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4921                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4922                 goto failed_mount_wq;
4923         }
4924
4925         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4926             !ext4_has_feature_encrypt(sb)) {
4927                 ext4_set_feature_encrypt(sb);
4928                 ext4_commit_super(sb, 1);
4929         }
4930
4931         /*
4932          * Get the # of file system overhead blocks from the
4933          * superblock if present.
4934          */
4935         if (es->s_overhead_clusters)
4936                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4937         else {
4938                 err = ext4_calculate_overhead(sb);
4939                 if (err)
4940                         goto failed_mount_wq;
4941         }
4942
4943         /*
4944          * The maximum number of concurrent works can be high and
4945          * concurrency isn't really necessary.  Limit it to 1.
4946          */
4947         EXT4_SB(sb)->rsv_conversion_wq =
4948                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4949         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4950                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4951                 ret = -ENOMEM;
4952                 goto failed_mount4;
4953         }
4954
4955         /*
4956          * The jbd2_journal_load will have done any necessary log recovery,
4957          * so we can safely mount the rest of the filesystem now.
4958          */
4959
4960         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4961         if (IS_ERR(root)) {
4962                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4963                 ret = PTR_ERR(root);
4964                 root = NULL;
4965                 goto failed_mount4;
4966         }
4967         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4968                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4969                 iput(root);
4970                 goto failed_mount4;
4971         }
4972
4973 #ifdef CONFIG_UNICODE
4974         if (sb->s_encoding)
4975                 sb->s_d_op = &ext4_dentry_ops;
4976 #endif
4977
4978         sb->s_root = d_make_root(root);
4979         if (!sb->s_root) {
4980                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4981                 ret = -ENOMEM;
4982                 goto failed_mount4;
4983         }
4984
4985         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4986         if (ret == -EROFS) {
4987                 sb->s_flags |= SB_RDONLY;
4988                 ret = 0;
4989         } else if (ret)
4990                 goto failed_mount4a;
4991
4992         ext4_set_resv_clusters(sb);
4993
4994         if (test_opt(sb, BLOCK_VALIDITY)) {
4995                 err = ext4_setup_system_zone(sb);
4996                 if (err) {
4997                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
4998                                  "zone (%d)", err);
4999                         goto failed_mount4a;
5000                 }
5001         }
5002         ext4_fc_replay_cleanup(sb);
5003
5004         ext4_ext_init(sb);
5005         err = ext4_mb_init(sb);
5006         if (err) {
5007                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5008                          err);
5009                 goto failed_mount5;
5010         }
5011
5012         block = ext4_count_free_clusters(sb);
5013         ext4_free_blocks_count_set(sbi->s_es,
5014                                    EXT4_C2B(sbi, block));
5015         ext4_superblock_csum_set(sb);
5016         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
5017                                   GFP_KERNEL);
5018         if (!err) {
5019                 unsigned long freei = ext4_count_free_inodes(sb);
5020                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
5021                 ext4_superblock_csum_set(sb);
5022                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
5023                                           GFP_KERNEL);
5024         }
5025         if (!err)
5026                 err = percpu_counter_init(&sbi->s_dirs_counter,
5027                                           ext4_count_dirs(sb), GFP_KERNEL);
5028         if (!err)
5029                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5030                                           GFP_KERNEL);
5031         if (!err)
5032                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5033
5034         if (err) {
5035                 ext4_msg(sb, KERN_ERR, "insufficient memory");
5036                 goto failed_mount6;
5037         }
5038
5039         if (ext4_has_feature_flex_bg(sb))
5040                 if (!ext4_fill_flex_info(sb)) {
5041                         ext4_msg(sb, KERN_ERR,
5042                                "unable to initialize "
5043                                "flex_bg meta info!");
5044                         goto failed_mount6;
5045                 }
5046
5047         err = ext4_register_li_request(sb, first_not_zeroed);
5048         if (err)
5049                 goto failed_mount6;
5050
5051         err = ext4_register_sysfs(sb);
5052         if (err)
5053                 goto failed_mount7;
5054
5055 #ifdef CONFIG_QUOTA
5056         /* Enable quota usage during mount. */
5057         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5058                 err = ext4_enable_quotas(sb);
5059                 if (err)
5060                         goto failed_mount8;
5061         }
5062 #endif  /* CONFIG_QUOTA */
5063
5064         /*
5065          * Save the original bdev mapping's wb_err value which could be
5066          * used to detect the metadata async write error.
5067          */
5068         spin_lock_init(&sbi->s_bdev_wb_lock);
5069         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5070                                  &sbi->s_bdev_wb_err);
5071         sb->s_bdev->bd_super = sb;
5072         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5073         ext4_orphan_cleanup(sb, es);
5074         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5075         if (needs_recovery) {
5076                 ext4_msg(sb, KERN_INFO, "recovery complete");
5077                 err = ext4_mark_recovery_complete(sb, es);
5078                 if (err)
5079                         goto failed_mount8;
5080         }
5081         if (EXT4_SB(sb)->s_journal) {
5082                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5083                         descr = " journalled data mode";
5084                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5085                         descr = " ordered data mode";
5086                 else
5087                         descr = " writeback data mode";
5088         } else
5089                 descr = "out journal";
5090
5091         if (test_opt(sb, DISCARD)) {
5092                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
5093                 if (!blk_queue_discard(q))
5094                         ext4_msg(sb, KERN_WARNING,
5095                                  "mounting with \"discard\" option, but "
5096                                  "the device does not support discard");
5097         }
5098
5099         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5100                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5101                          "Opts: %.*s%s%s. Quota mode: %s.", descr,
5102                          (int) sizeof(sbi->s_es->s_mount_opts),
5103                          sbi->s_es->s_mount_opts,
5104                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data,
5105                          ext4_quota_mode(sb));
5106
5107         if (es->s_error_count)
5108                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5109
5110         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5111         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5112         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5113         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5114         atomic_set(&sbi->s_warning_count, 0);
5115         atomic_set(&sbi->s_msg_count, 0);
5116
5117         kfree(orig_data);
5118         return 0;
5119
5120 cantfind_ext4:
5121         if (!silent)
5122                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5123         goto failed_mount;
5124
5125 failed_mount8:
5126         ext4_unregister_sysfs(sb);
5127         kobject_put(&sbi->s_kobj);
5128 failed_mount7:
5129         ext4_unregister_li_request(sb);
5130 failed_mount6:
5131         ext4_mb_release(sb);
5132         rcu_read_lock();
5133         flex_groups = rcu_dereference(sbi->s_flex_groups);
5134         if (flex_groups) {
5135                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5136                         kvfree(flex_groups[i]);
5137                 kvfree(flex_groups);
5138         }
5139         rcu_read_unlock();
5140         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5141         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5142         percpu_counter_destroy(&sbi->s_dirs_counter);
5143         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5144         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5145 failed_mount5:
5146         ext4_ext_release(sb);
5147         ext4_release_system_zone(sb);
5148 failed_mount4a:
5149         dput(sb->s_root);
5150         sb->s_root = NULL;
5151 failed_mount4:
5152         ext4_msg(sb, KERN_ERR, "mount failed");
5153         if (EXT4_SB(sb)->rsv_conversion_wq)
5154                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5155 failed_mount_wq:
5156         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5157         sbi->s_ea_inode_cache = NULL;
5158
5159         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5160         sbi->s_ea_block_cache = NULL;
5161
5162         if (sbi->s_journal) {
5163                 jbd2_journal_destroy(sbi->s_journal);
5164                 sbi->s_journal = NULL;
5165         }
5166 failed_mount3a:
5167         ext4_es_unregister_shrinker(sbi);
5168 failed_mount3:
5169         del_timer_sync(&sbi->s_err_report);
5170         if (sbi->s_mmp_tsk)
5171                 kthread_stop(sbi->s_mmp_tsk);
5172 failed_mount2:
5173         rcu_read_lock();
5174         group_desc = rcu_dereference(sbi->s_group_desc);
5175         for (i = 0; i < db_count; i++)
5176                 brelse(group_desc[i]);
5177         kvfree(group_desc);
5178         rcu_read_unlock();
5179 failed_mount:
5180         if (sbi->s_chksum_driver)
5181                 crypto_free_shash(sbi->s_chksum_driver);
5182
5183 #ifdef CONFIG_UNICODE
5184         utf8_unload(sb->s_encoding);
5185 #endif
5186
5187 #ifdef CONFIG_QUOTA
5188         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5189                 kfree(get_qf_name(sb, sbi, i));
5190 #endif
5191         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5192         ext4_blkdev_remove(sbi);
5193         brelse(bh);
5194 out_fail:
5195         sb->s_fs_info = NULL;
5196         kfree(sbi->s_blockgroup_lock);
5197 out_free_base:
5198         kfree(sbi);
5199         kfree(orig_data);
5200         fs_put_dax(dax_dev);
5201         return err ? err : ret;
5202 }
5203
5204 /*
5205  * Setup any per-fs journal parameters now.  We'll do this both on
5206  * initial mount, once the journal has been initialised but before we've
5207  * done any recovery; and again on any subsequent remount.
5208  */
5209 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5210 {
5211         struct ext4_sb_info *sbi = EXT4_SB(sb);
5212
5213         journal->j_commit_interval = sbi->s_commit_interval;
5214         journal->j_min_batch_time = sbi->s_min_batch_time;
5215         journal->j_max_batch_time = sbi->s_max_batch_time;
5216         ext4_fc_init(sb, journal);
5217
5218         write_lock(&journal->j_state_lock);
5219         if (test_opt(sb, BARRIER))
5220                 journal->j_flags |= JBD2_BARRIER;
5221         else
5222                 journal->j_flags &= ~JBD2_BARRIER;
5223         if (test_opt(sb, DATA_ERR_ABORT))
5224                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5225         else
5226                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5227         write_unlock(&journal->j_state_lock);
5228 }
5229
5230 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5231                                              unsigned int journal_inum)
5232 {
5233         struct inode *journal_inode;
5234
5235         /*
5236          * Test for the existence of a valid inode on disk.  Bad things
5237          * happen if we iget() an unused inode, as the subsequent iput()
5238          * will try to delete it.
5239          */
5240         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5241         if (IS_ERR(journal_inode)) {
5242                 ext4_msg(sb, KERN_ERR, "no journal found");
5243                 return NULL;
5244         }
5245         if (!journal_inode->i_nlink) {
5246                 make_bad_inode(journal_inode);
5247                 iput(journal_inode);
5248                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5249                 return NULL;
5250         }
5251
5252         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5253                   journal_inode, journal_inode->i_size);
5254         if (!S_ISREG(journal_inode->i_mode)) {
5255                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5256                 iput(journal_inode);
5257                 return NULL;
5258         }
5259         return journal_inode;
5260 }
5261
5262 static journal_t *ext4_get_journal(struct super_block *sb,
5263                                    unsigned int journal_inum)
5264 {
5265         struct inode *journal_inode;
5266         journal_t *journal;
5267
5268         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5269                 return NULL;
5270
5271         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5272         if (!journal_inode)
5273                 return NULL;
5274
5275         journal = jbd2_journal_init_inode(journal_inode);
5276         if (!journal) {
5277                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5278                 iput(journal_inode);
5279                 return NULL;
5280         }
5281         journal->j_private = sb;
5282         ext4_init_journal_params(sb, journal);
5283         return journal;
5284 }
5285
5286 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5287                                        dev_t j_dev)
5288 {
5289         struct buffer_head *bh;
5290         journal_t *journal;
5291         ext4_fsblk_t start;
5292         ext4_fsblk_t len;
5293         int hblock, blocksize;
5294         ext4_fsblk_t sb_block;
5295         unsigned long offset;
5296         struct ext4_super_block *es;
5297         struct block_device *bdev;
5298
5299         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5300                 return NULL;
5301
5302         bdev = ext4_blkdev_get(j_dev, sb);
5303         if (bdev == NULL)
5304                 return NULL;
5305
5306         blocksize = sb->s_blocksize;
5307         hblock = bdev_logical_block_size(bdev);
5308         if (blocksize < hblock) {
5309                 ext4_msg(sb, KERN_ERR,
5310                         "blocksize too small for journal device");
5311                 goto out_bdev;
5312         }
5313
5314         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5315         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5316         set_blocksize(bdev, blocksize);
5317         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5318                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5319                        "external journal");
5320                 goto out_bdev;
5321         }
5322
5323         es = (struct ext4_super_block *) (bh->b_data + offset);
5324         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5325             !(le32_to_cpu(es->s_feature_incompat) &
5326               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5327                 ext4_msg(sb, KERN_ERR, "external journal has "
5328                                         "bad superblock");
5329                 brelse(bh);
5330                 goto out_bdev;
5331         }
5332
5333         if ((le32_to_cpu(es->s_feature_ro_compat) &
5334              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5335             es->s_checksum != ext4_superblock_csum(sb, es)) {
5336                 ext4_msg(sb, KERN_ERR, "external journal has "
5337                                        "corrupt superblock");
5338                 brelse(bh);
5339                 goto out_bdev;
5340         }
5341
5342         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5343                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5344                 brelse(bh);
5345                 goto out_bdev;
5346         }
5347
5348         len = ext4_blocks_count(es);
5349         start = sb_block + 1;
5350         brelse(bh);     /* we're done with the superblock */
5351
5352         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5353                                         start, len, blocksize);
5354         if (!journal) {
5355                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5356                 goto out_bdev;
5357         }
5358         journal->j_private = sb;
5359         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5360                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5361                 goto out_journal;
5362         }
5363         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5364                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5365                                         "user (unsupported) - %d",
5366                         be32_to_cpu(journal->j_superblock->s_nr_users));
5367                 goto out_journal;
5368         }
5369         EXT4_SB(sb)->s_journal_bdev = bdev;
5370         ext4_init_journal_params(sb, journal);
5371         return journal;
5372
5373 out_journal:
5374         jbd2_journal_destroy(journal);
5375 out_bdev:
5376         ext4_blkdev_put(bdev);
5377         return NULL;
5378 }
5379
5380 static int ext4_load_journal(struct super_block *sb,
5381                              struct ext4_super_block *es,
5382                              unsigned long journal_devnum)
5383 {
5384         journal_t *journal;
5385         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5386         dev_t journal_dev;
5387         int err = 0;
5388         int really_read_only;
5389         int journal_dev_ro;
5390
5391         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5392                 return -EFSCORRUPTED;
5393
5394         if (journal_devnum &&
5395             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5396                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5397                         "numbers have changed");
5398                 journal_dev = new_decode_dev(journal_devnum);
5399         } else
5400                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5401
5402         if (journal_inum && journal_dev) {
5403                 ext4_msg(sb, KERN_ERR,
5404                          "filesystem has both journal inode and journal device!");
5405                 return -EINVAL;
5406         }
5407
5408         if (journal_inum) {
5409                 journal = ext4_get_journal(sb, journal_inum);
5410                 if (!journal)
5411                         return -EINVAL;
5412         } else {
5413                 journal = ext4_get_dev_journal(sb, journal_dev);
5414                 if (!journal)
5415                         return -EINVAL;
5416         }
5417
5418         journal_dev_ro = bdev_read_only(journal->j_dev);
5419         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5420
5421         if (journal_dev_ro && !sb_rdonly(sb)) {
5422                 ext4_msg(sb, KERN_ERR,
5423                          "journal device read-only, try mounting with '-o ro'");
5424                 err = -EROFS;
5425                 goto err_out;
5426         }
5427
5428         /*
5429          * Are we loading a blank journal or performing recovery after a
5430          * crash?  For recovery, we need to check in advance whether we
5431          * can get read-write access to the device.
5432          */
5433         if (ext4_has_feature_journal_needs_recovery(sb)) {
5434                 if (sb_rdonly(sb)) {
5435                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5436                                         "required on readonly filesystem");
5437                         if (really_read_only) {
5438                                 ext4_msg(sb, KERN_ERR, "write access "
5439                                         "unavailable, cannot proceed "
5440                                         "(try mounting with noload)");
5441                                 err = -EROFS;
5442                                 goto err_out;
5443                         }
5444                         ext4_msg(sb, KERN_INFO, "write access will "
5445                                "be enabled during recovery");
5446                 }
5447         }
5448
5449         if (!(journal->j_flags & JBD2_BARRIER))
5450                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5451
5452         if (!ext4_has_feature_journal_needs_recovery(sb))
5453                 err = jbd2_journal_wipe(journal, !really_read_only);
5454         if (!err) {
5455                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5456                 if (save)
5457                         memcpy(save, ((char *) es) +
5458                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5459                 err = jbd2_journal_load(journal);
5460                 if (save)
5461                         memcpy(((char *) es) + EXT4_S_ERR_START,
5462                                save, EXT4_S_ERR_LEN);
5463                 kfree(save);
5464         }
5465
5466         if (err) {
5467                 ext4_msg(sb, KERN_ERR, "error loading journal");
5468                 goto err_out;
5469         }
5470
5471         EXT4_SB(sb)->s_journal = journal;
5472         err = ext4_clear_journal_err(sb, es);
5473         if (err) {
5474                 EXT4_SB(sb)->s_journal = NULL;
5475                 jbd2_journal_destroy(journal);
5476                 return err;
5477         }
5478
5479         if (!really_read_only && journal_devnum &&
5480             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5481                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5482
5483                 /* Make sure we flush the recovery flag to disk. */
5484                 ext4_commit_super(sb, 1);
5485         }
5486
5487         return 0;
5488
5489 err_out:
5490         jbd2_journal_destroy(journal);
5491         return err;
5492 }
5493
5494 static int ext4_commit_super(struct super_block *sb, int sync)
5495 {
5496         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5497         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5498         int error = 0;
5499
5500         if (!sbh || block_device_ejected(sb))
5501                 return error;
5502
5503         /*
5504          * If the file system is mounted read-only, don't update the
5505          * superblock write time.  This avoids updating the superblock
5506          * write time when we are mounting the root file system
5507          * read/only but we need to replay the journal; at that point,
5508          * for people who are east of GMT and who make their clock
5509          * tick in localtime for Windows bug-for-bug compatibility,
5510          * the clock is set in the future, and this will cause e2fsck
5511          * to complain and force a full file system check.
5512          */
5513         if (!(sb->s_flags & SB_RDONLY))
5514                 ext4_update_tstamp(es, s_wtime);
5515         if (sb->s_bdev->bd_part)
5516                 es->s_kbytes_written =
5517                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5518                             ((part_stat_read(sb->s_bdev->bd_part,
5519                                              sectors[STAT_WRITE]) -
5520                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5521         else
5522                 es->s_kbytes_written =
5523                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5524         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5525                 ext4_free_blocks_count_set(es,
5526                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5527                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5528         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5529                 es->s_free_inodes_count =
5530                         cpu_to_le32(percpu_counter_sum_positive(
5531                                 &EXT4_SB(sb)->s_freeinodes_counter));
5532         BUFFER_TRACE(sbh, "marking dirty");
5533         ext4_superblock_csum_set(sb);
5534         if (sync)
5535                 lock_buffer(sbh);
5536         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5537                 /*
5538                  * Oh, dear.  A previous attempt to write the
5539                  * superblock failed.  This could happen because the
5540                  * USB device was yanked out.  Or it could happen to
5541                  * be a transient write error and maybe the block will
5542                  * be remapped.  Nothing we can do but to retry the
5543                  * write and hope for the best.
5544                  */
5545                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5546                        "superblock detected");
5547                 clear_buffer_write_io_error(sbh);
5548                 set_buffer_uptodate(sbh);
5549         }
5550         mark_buffer_dirty(sbh);
5551         if (sync) {
5552                 unlock_buffer(sbh);
5553                 error = __sync_dirty_buffer(sbh,
5554                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5555                 if (buffer_write_io_error(sbh)) {
5556                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5557                                "superblock");
5558                         clear_buffer_write_io_error(sbh);
5559                         set_buffer_uptodate(sbh);
5560                 }
5561         }
5562         return error;
5563 }
5564
5565 /*
5566  * Have we just finished recovery?  If so, and if we are mounting (or
5567  * remounting) the filesystem readonly, then we will end up with a
5568  * consistent fs on disk.  Record that fact.
5569  */
5570 static int ext4_mark_recovery_complete(struct super_block *sb,
5571                                        struct ext4_super_block *es)
5572 {
5573         int err;
5574         journal_t *journal = EXT4_SB(sb)->s_journal;
5575
5576         if (!ext4_has_feature_journal(sb)) {
5577                 if (journal != NULL) {
5578                         ext4_error(sb, "Journal got removed while the fs was "
5579                                    "mounted!");
5580                         return -EFSCORRUPTED;
5581                 }
5582                 return 0;
5583         }
5584         jbd2_journal_lock_updates(journal);
5585         err = jbd2_journal_flush(journal);
5586         if (err < 0)
5587                 goto out;
5588
5589         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5590                 ext4_clear_feature_journal_needs_recovery(sb);
5591                 ext4_commit_super(sb, 1);
5592         }
5593 out:
5594         jbd2_journal_unlock_updates(journal);
5595         return err;
5596 }
5597
5598 /*
5599  * If we are mounting (or read-write remounting) a filesystem whose journal
5600  * has recorded an error from a previous lifetime, move that error to the
5601  * main filesystem now.
5602  */
5603 static int ext4_clear_journal_err(struct super_block *sb,
5604                                    struct ext4_super_block *es)
5605 {
5606         journal_t *journal;
5607         int j_errno;
5608         const char *errstr;
5609
5610         if (!ext4_has_feature_journal(sb)) {
5611                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5612                 return -EFSCORRUPTED;
5613         }
5614
5615         journal = EXT4_SB(sb)->s_journal;
5616
5617         /*
5618          * Now check for any error status which may have been recorded in the
5619          * journal by a prior ext4_error() or ext4_abort()
5620          */
5621
5622         j_errno = jbd2_journal_errno(journal);
5623         if (j_errno) {
5624                 char nbuf[16];
5625
5626                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5627                 ext4_warning(sb, "Filesystem error recorded "
5628                              "from previous mount: %s", errstr);
5629                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5630
5631                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5632                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5633                 ext4_commit_super(sb, 1);
5634
5635                 jbd2_journal_clear_err(journal);
5636                 jbd2_journal_update_sb_errno(journal);
5637         }
5638         return 0;
5639 }
5640
5641 /*
5642  * Force the running and committing transactions to commit,
5643  * and wait on the commit.
5644  */
5645 int ext4_force_commit(struct super_block *sb)
5646 {
5647         journal_t *journal;
5648
5649         if (sb_rdonly(sb))
5650                 return 0;
5651
5652         journal = EXT4_SB(sb)->s_journal;
5653         return ext4_journal_force_commit(journal);
5654 }
5655
5656 static int ext4_sync_fs(struct super_block *sb, int wait)
5657 {
5658         int ret = 0;
5659         tid_t target;
5660         bool needs_barrier = false;
5661         struct ext4_sb_info *sbi = EXT4_SB(sb);
5662
5663         if (unlikely(ext4_forced_shutdown(sbi)))
5664                 return 0;
5665
5666         trace_ext4_sync_fs(sb, wait);
5667         flush_workqueue(sbi->rsv_conversion_wq);
5668         /*
5669          * Writeback quota in non-journalled quota case - journalled quota has
5670          * no dirty dquots
5671          */
5672         dquot_writeback_dquots(sb, -1);
5673         /*
5674          * Data writeback is possible w/o journal transaction, so barrier must
5675          * being sent at the end of the function. But we can skip it if
5676          * transaction_commit will do it for us.
5677          */
5678         if (sbi->s_journal) {
5679                 target = jbd2_get_latest_transaction(sbi->s_journal);
5680                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5681                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5682                         needs_barrier = true;
5683
5684                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5685                         if (wait)
5686                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5687                                                            target);
5688                 }
5689         } else if (wait && test_opt(sb, BARRIER))
5690                 needs_barrier = true;
5691         if (needs_barrier) {
5692                 int err;
5693                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL);
5694                 if (!ret)
5695                         ret = err;
5696         }
5697
5698         return ret;
5699 }
5700
5701 /*
5702  * LVM calls this function before a (read-only) snapshot is created.  This
5703  * gives us a chance to flush the journal completely and mark the fs clean.
5704  *
5705  * Note that only this function cannot bring a filesystem to be in a clean
5706  * state independently. It relies on upper layer to stop all data & metadata
5707  * modifications.
5708  */
5709 static int ext4_freeze(struct super_block *sb)
5710 {
5711         int error = 0;
5712         journal_t *journal;
5713
5714         if (sb_rdonly(sb))
5715                 return 0;
5716
5717         journal = EXT4_SB(sb)->s_journal;
5718
5719         if (journal) {
5720                 /* Now we set up the journal barrier. */
5721                 jbd2_journal_lock_updates(journal);
5722
5723                 /*
5724                  * Don't clear the needs_recovery flag if we failed to
5725                  * flush the journal.
5726                  */
5727                 error = jbd2_journal_flush(journal);
5728                 if (error < 0)
5729                         goto out;
5730
5731                 /* Journal blocked and flushed, clear needs_recovery flag. */
5732                 ext4_clear_feature_journal_needs_recovery(sb);
5733         }
5734
5735         error = ext4_commit_super(sb, 1);
5736 out:
5737         if (journal)
5738                 /* we rely on upper layer to stop further updates */
5739                 jbd2_journal_unlock_updates(journal);
5740         return error;
5741 }
5742
5743 /*
5744  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5745  * flag here, even though the filesystem is not technically dirty yet.
5746  */
5747 static int ext4_unfreeze(struct super_block *sb)
5748 {
5749         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5750                 return 0;
5751
5752         if (EXT4_SB(sb)->s_journal) {
5753                 /* Reset the needs_recovery flag before the fs is unlocked. */
5754                 ext4_set_feature_journal_needs_recovery(sb);
5755         }
5756
5757         ext4_commit_super(sb, 1);
5758         return 0;
5759 }
5760
5761 /*
5762  * Structure to save mount options for ext4_remount's benefit
5763  */
5764 struct ext4_mount_options {
5765         unsigned long s_mount_opt;
5766         unsigned long s_mount_opt2;
5767         kuid_t s_resuid;
5768         kgid_t s_resgid;
5769         unsigned long s_commit_interval;
5770         u32 s_min_batch_time, s_max_batch_time;
5771 #ifdef CONFIG_QUOTA
5772         int s_jquota_fmt;
5773         char *s_qf_names[EXT4_MAXQUOTAS];
5774 #endif
5775 };
5776
5777 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5778 {
5779         struct ext4_super_block *es;
5780         struct ext4_sb_info *sbi = EXT4_SB(sb);
5781         unsigned long old_sb_flags, vfs_flags;
5782         struct ext4_mount_options old_opts;
5783         int enable_quota = 0;
5784         ext4_group_t g;
5785         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5786         int err = 0;
5787 #ifdef CONFIG_QUOTA
5788         int i, j;
5789         char *to_free[EXT4_MAXQUOTAS];
5790 #endif
5791         char *orig_data = kstrdup(data, GFP_KERNEL);
5792
5793         if (data && !orig_data)
5794                 return -ENOMEM;
5795
5796         /* Store the original options */
5797         old_sb_flags = sb->s_flags;
5798         old_opts.s_mount_opt = sbi->s_mount_opt;
5799         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5800         old_opts.s_resuid = sbi->s_resuid;
5801         old_opts.s_resgid = sbi->s_resgid;
5802         old_opts.s_commit_interval = sbi->s_commit_interval;
5803         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5804         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5805 #ifdef CONFIG_QUOTA
5806         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5807         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5808                 if (sbi->s_qf_names[i]) {
5809                         char *qf_name = get_qf_name(sb, sbi, i);
5810
5811                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5812                         if (!old_opts.s_qf_names[i]) {
5813                                 for (j = 0; j < i; j++)
5814                                         kfree(old_opts.s_qf_names[j]);
5815                                 kfree(orig_data);
5816                                 return -ENOMEM;
5817                         }
5818                 } else
5819                         old_opts.s_qf_names[i] = NULL;
5820 #endif
5821         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5822                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5823
5824         /*
5825          * Some options can be enabled by ext4 and/or by VFS mount flag
5826          * either way we need to make sure it matches in both *flags and
5827          * s_flags. Copy those selected flags from *flags to s_flags
5828          */
5829         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5830         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5831
5832         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5833                 err = -EINVAL;
5834                 goto restore_opts;
5835         }
5836
5837         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5838             test_opt(sb, JOURNAL_CHECKSUM)) {
5839                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5840                          "during remount not supported; ignoring");
5841                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5842         }
5843
5844         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5845                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5846                         ext4_msg(sb, KERN_ERR, "can't mount with "
5847                                  "both data=journal and delalloc");
5848                         err = -EINVAL;
5849                         goto restore_opts;
5850                 }
5851                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5852                         ext4_msg(sb, KERN_ERR, "can't mount with "
5853                                  "both data=journal and dioread_nolock");
5854                         err = -EINVAL;
5855                         goto restore_opts;
5856                 }
5857         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5858                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5859                         ext4_msg(sb, KERN_ERR, "can't mount with "
5860                                 "journal_async_commit in data=ordered mode");
5861                         err = -EINVAL;
5862                         goto restore_opts;
5863                 }
5864         }
5865
5866         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5867                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5868                 err = -EINVAL;
5869                 goto restore_opts;
5870         }
5871
5872         if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
5873                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5874
5875         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5876                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5877
5878         es = sbi->s_es;
5879
5880         if (sbi->s_journal) {
5881                 ext4_init_journal_params(sb, sbi->s_journal);
5882                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5883         }
5884
5885         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5886                 if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
5887                         err = -EROFS;
5888                         goto restore_opts;
5889                 }
5890
5891                 if (*flags & SB_RDONLY) {
5892                         err = sync_filesystem(sb);
5893                         if (err < 0)
5894                                 goto restore_opts;
5895                         err = dquot_suspend(sb, -1);
5896                         if (err < 0)
5897                                 goto restore_opts;
5898
5899                         /*
5900                          * First of all, the unconditional stuff we have to do
5901                          * to disable replay of the journal when we next remount
5902                          */
5903                         sb->s_flags |= SB_RDONLY;
5904
5905                         /*
5906                          * OK, test if we are remounting a valid rw partition
5907                          * readonly, and if so set the rdonly flag and then
5908                          * mark the partition as valid again.
5909                          */
5910                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5911                             (sbi->s_mount_state & EXT4_VALID_FS))
5912                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5913
5914                         if (sbi->s_journal) {
5915                                 /*
5916                                  * We let remount-ro finish even if marking fs
5917                                  * as clean failed...
5918                                  */
5919                                 ext4_mark_recovery_complete(sb, es);
5920                         }
5921                         if (sbi->s_mmp_tsk)
5922                                 kthread_stop(sbi->s_mmp_tsk);
5923                 } else {
5924                         /* Make sure we can mount this feature set readwrite */
5925                         if (ext4_has_feature_readonly(sb) ||
5926                             !ext4_feature_set_ok(sb, 0)) {
5927                                 err = -EROFS;
5928                                 goto restore_opts;
5929                         }
5930                         /*
5931                          * Make sure the group descriptor checksums
5932                          * are sane.  If they aren't, refuse to remount r/w.
5933                          */
5934                         for (g = 0; g < sbi->s_groups_count; g++) {
5935                                 struct ext4_group_desc *gdp =
5936                                         ext4_get_group_desc(sb, g, NULL);
5937
5938                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5939                                         ext4_msg(sb, KERN_ERR,
5940                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5941                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5942                                                le16_to_cpu(gdp->bg_checksum));
5943                                         err = -EFSBADCRC;
5944                                         goto restore_opts;
5945                                 }
5946                         }
5947
5948                         /*
5949                          * If we have an unprocessed orphan list hanging
5950                          * around from a previously readonly bdev mount,
5951                          * require a full umount/remount for now.
5952                          */
5953                         if (es->s_last_orphan) {
5954                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5955                                        "remount RDWR because of unprocessed "
5956                                        "orphan inode list.  Please "
5957                                        "umount/remount instead");
5958                                 err = -EINVAL;
5959                                 goto restore_opts;
5960                         }
5961
5962                         /*
5963                          * Mounting a RDONLY partition read-write, so reread
5964                          * and store the current valid flag.  (It may have
5965                          * been changed by e2fsck since we originally mounted
5966                          * the partition.)
5967                          */
5968                         if (sbi->s_journal) {
5969                                 err = ext4_clear_journal_err(sb, es);
5970                                 if (err)
5971                                         goto restore_opts;
5972                         }
5973                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5974
5975                         err = ext4_setup_super(sb, es, 0);
5976                         if (err)
5977                                 goto restore_opts;
5978
5979                         sb->s_flags &= ~SB_RDONLY;
5980                         if (ext4_has_feature_mmp(sb))
5981                                 if (ext4_multi_mount_protect(sb,
5982                                                 le64_to_cpu(es->s_mmp_block))) {
5983                                         err = -EROFS;
5984                                         goto restore_opts;
5985                                 }
5986                         enable_quota = 1;
5987                 }
5988         }
5989
5990         /*
5991          * Reinitialize lazy itable initialization thread based on
5992          * current settings
5993          */
5994         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5995                 ext4_unregister_li_request(sb);
5996         else {
5997                 ext4_group_t first_not_zeroed;
5998                 first_not_zeroed = ext4_has_uninit_itable(sb);
5999                 ext4_register_li_request(sb, first_not_zeroed);
6000         }
6001
6002         /*
6003          * Handle creation of system zone data early because it can fail.
6004          * Releasing of existing data is done when we are sure remount will
6005          * succeed.
6006          */
6007         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6008                 err = ext4_setup_system_zone(sb);
6009                 if (err)
6010                         goto restore_opts;
6011         }
6012
6013         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6014                 err = ext4_commit_super(sb, 1);
6015                 if (err)
6016                         goto restore_opts;
6017         }
6018
6019 #ifdef CONFIG_QUOTA
6020         /* Release old quota file names */
6021         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6022                 kfree(old_opts.s_qf_names[i]);
6023         if (enable_quota) {
6024                 if (sb_any_quota_suspended(sb))
6025                         dquot_resume(sb, -1);
6026                 else if (ext4_has_feature_quota(sb)) {
6027                         err = ext4_enable_quotas(sb);
6028                         if (err)
6029                                 goto restore_opts;
6030                 }
6031         }
6032 #endif
6033         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6034                 ext4_release_system_zone(sb);
6035
6036         /*
6037          * Some options can be enabled by ext4 and/or by VFS mount flag
6038          * either way we need to make sure it matches in both *flags and
6039          * s_flags. Copy those selected flags from s_flags to *flags
6040          */
6041         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
6042
6043         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s. Quota mode: %s.",
6044                  orig_data, ext4_quota_mode(sb));
6045         kfree(orig_data);
6046         return 0;
6047
6048 restore_opts:
6049         sb->s_flags = old_sb_flags;
6050         sbi->s_mount_opt = old_opts.s_mount_opt;
6051         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6052         sbi->s_resuid = old_opts.s_resuid;
6053         sbi->s_resgid = old_opts.s_resgid;
6054         sbi->s_commit_interval = old_opts.s_commit_interval;
6055         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6056         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6057         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6058                 ext4_release_system_zone(sb);
6059 #ifdef CONFIG_QUOTA
6060         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6061         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6062                 to_free[i] = get_qf_name(sb, sbi, i);
6063                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6064         }
6065         synchronize_rcu();
6066         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6067                 kfree(to_free[i]);
6068 #endif
6069         kfree(orig_data);
6070         return err;
6071 }
6072
6073 #ifdef CONFIG_QUOTA
6074 static int ext4_statfs_project(struct super_block *sb,
6075                                kprojid_t projid, struct kstatfs *buf)
6076 {
6077         struct kqid qid;
6078         struct dquot *dquot;
6079         u64 limit;
6080         u64 curblock;
6081
6082         qid = make_kqid_projid(projid);
6083         dquot = dqget(sb, qid);
6084         if (IS_ERR(dquot))
6085                 return PTR_ERR(dquot);
6086         spin_lock(&dquot->dq_dqb_lock);
6087
6088         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6089                              dquot->dq_dqb.dqb_bhardlimit);
6090         limit >>= sb->s_blocksize_bits;
6091
6092         if (limit && buf->f_blocks > limit) {
6093                 curblock = (dquot->dq_dqb.dqb_curspace +
6094                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6095                 buf->f_blocks = limit;
6096                 buf->f_bfree = buf->f_bavail =
6097                         (buf->f_blocks > curblock) ?
6098                          (buf->f_blocks - curblock) : 0;
6099         }
6100
6101         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6102                              dquot->dq_dqb.dqb_ihardlimit);
6103         if (limit && buf->f_files > limit) {
6104                 buf->f_files = limit;
6105                 buf->f_ffree =
6106                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6107                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6108         }
6109
6110         spin_unlock(&dquot->dq_dqb_lock);
6111         dqput(dquot);
6112         return 0;
6113 }
6114 #endif
6115
6116 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6117 {
6118         struct super_block *sb = dentry->d_sb;
6119         struct ext4_sb_info *sbi = EXT4_SB(sb);
6120         struct ext4_super_block *es = sbi->s_es;
6121         ext4_fsblk_t overhead = 0, resv_blocks;
6122         u64 fsid;
6123         s64 bfree;
6124         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6125
6126         if (!test_opt(sb, MINIX_DF))
6127                 overhead = sbi->s_overhead;
6128
6129         buf->f_type = EXT4_SUPER_MAGIC;
6130         buf->f_bsize = sb->s_blocksize;
6131         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6132         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6133                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6134         /* prevent underflow in case that few free space is available */
6135         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6136         buf->f_bavail = buf->f_bfree -
6137                         (ext4_r_blocks_count(es) + resv_blocks);
6138         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6139                 buf->f_bavail = 0;
6140         buf->f_files = le32_to_cpu(es->s_inodes_count);
6141         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6142         buf->f_namelen = EXT4_NAME_LEN;
6143         fsid = le64_to_cpup((void *)es->s_uuid) ^
6144                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
6145         buf->f_fsid = u64_to_fsid(fsid);
6146
6147 #ifdef CONFIG_QUOTA
6148         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6149             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6150                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6151 #endif
6152         return 0;
6153 }
6154
6155
6156 #ifdef CONFIG_QUOTA
6157
6158 /*
6159  * Helper functions so that transaction is started before we acquire dqio_sem
6160  * to keep correct lock ordering of transaction > dqio_sem
6161  */
6162 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6163 {
6164         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6165 }
6166
6167 static int ext4_write_dquot(struct dquot *dquot)
6168 {
6169         int ret, err;
6170         handle_t *handle;
6171         struct inode *inode;
6172
6173         inode = dquot_to_inode(dquot);
6174         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6175                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6176         if (IS_ERR(handle))
6177                 return PTR_ERR(handle);
6178         ret = dquot_commit(dquot);
6179         err = ext4_journal_stop(handle);
6180         if (!ret)
6181                 ret = err;
6182         return ret;
6183 }
6184
6185 static int ext4_acquire_dquot(struct dquot *dquot)
6186 {
6187         int ret, err;
6188         handle_t *handle;
6189
6190         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6191                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6192         if (IS_ERR(handle))
6193                 return PTR_ERR(handle);
6194         ret = dquot_acquire(dquot);
6195         err = ext4_journal_stop(handle);
6196         if (!ret)
6197                 ret = err;
6198         return ret;
6199 }
6200
6201 static int ext4_release_dquot(struct dquot *dquot)
6202 {
6203         int ret, err;
6204         handle_t *handle;
6205
6206         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6207                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6208         if (IS_ERR(handle)) {
6209                 /* Release dquot anyway to avoid endless cycle in dqput() */
6210                 dquot_release(dquot);
6211                 return PTR_ERR(handle);
6212         }
6213         ret = dquot_release(dquot);
6214         err = ext4_journal_stop(handle);
6215         if (!ret)
6216                 ret = err;
6217         return ret;
6218 }
6219
6220 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6221 {
6222         struct super_block *sb = dquot->dq_sb;
6223
6224         if (ext4_is_quota_journalled(sb)) {
6225                 dquot_mark_dquot_dirty(dquot);
6226                 return ext4_write_dquot(dquot);
6227         } else {
6228                 return dquot_mark_dquot_dirty(dquot);
6229         }
6230 }
6231
6232 static int ext4_write_info(struct super_block *sb, int type)
6233 {
6234         int ret, err;
6235         handle_t *handle;
6236
6237         /* Data block + inode block */
6238         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6239         if (IS_ERR(handle))
6240                 return PTR_ERR(handle);
6241         ret = dquot_commit_info(sb, type);
6242         err = ext4_journal_stop(handle);
6243         if (!ret)
6244                 ret = err;
6245         return ret;
6246 }
6247
6248 /*
6249  * Turn on quotas during mount time - we need to find
6250  * the quota file and such...
6251  */
6252 static int ext4_quota_on_mount(struct super_block *sb, int type)
6253 {
6254         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
6255                                         EXT4_SB(sb)->s_jquota_fmt, type);
6256 }
6257
6258 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6259 {
6260         struct ext4_inode_info *ei = EXT4_I(inode);
6261
6262         /* The first argument of lockdep_set_subclass has to be
6263          * *exactly* the same as the argument to init_rwsem() --- in
6264          * this case, in init_once() --- or lockdep gets unhappy
6265          * because the name of the lock is set using the
6266          * stringification of the argument to init_rwsem().
6267          */
6268         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6269         lockdep_set_subclass(&ei->i_data_sem, subclass);
6270 }
6271
6272 /*
6273  * Standard function to be called on quota_on
6274  */
6275 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6276                          const struct path *path)
6277 {
6278         int err;
6279
6280         if (!test_opt(sb, QUOTA))
6281                 return -EINVAL;
6282
6283         /* Quotafile not on the same filesystem? */
6284         if (path->dentry->d_sb != sb)
6285                 return -EXDEV;
6286
6287         /* Quota already enabled for this file? */
6288         if (IS_NOQUOTA(d_inode(path->dentry)))
6289                 return -EBUSY;
6290
6291         /* Journaling quota? */
6292         if (EXT4_SB(sb)->s_qf_names[type]) {
6293                 /* Quotafile not in fs root? */
6294                 if (path->dentry->d_parent != sb->s_root)
6295                         ext4_msg(sb, KERN_WARNING,
6296                                 "Quota file not on filesystem root. "
6297                                 "Journaled quota will not work");
6298                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6299         } else {
6300                 /*
6301                  * Clear the flag just in case mount options changed since
6302                  * last time.
6303                  */
6304                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6305         }
6306
6307         /*
6308          * When we journal data on quota file, we have to flush journal to see
6309          * all updates to the file when we bypass pagecache...
6310          */
6311         if (EXT4_SB(sb)->s_journal &&
6312             ext4_should_journal_data(d_inode(path->dentry))) {
6313                 /*
6314                  * We don't need to lock updates but journal_flush() could
6315                  * otherwise be livelocked...
6316                  */
6317                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6318                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
6319                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6320                 if (err)
6321                         return err;
6322         }
6323
6324         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6325         err = dquot_quota_on(sb, type, format_id, path);
6326         if (err) {
6327                 lockdep_set_quota_inode(path->dentry->d_inode,
6328                                              I_DATA_SEM_NORMAL);
6329         } else {
6330                 struct inode *inode = d_inode(path->dentry);
6331                 handle_t *handle;
6332
6333                 /*
6334                  * Set inode flags to prevent userspace from messing with quota
6335                  * files. If this fails, we return success anyway since quotas
6336                  * are already enabled and this is not a hard failure.
6337                  */
6338                 inode_lock(inode);
6339                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6340                 if (IS_ERR(handle))
6341                         goto unlock_inode;
6342                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6343                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6344                                 S_NOATIME | S_IMMUTABLE);
6345                 err = ext4_mark_inode_dirty(handle, inode);
6346                 ext4_journal_stop(handle);
6347         unlock_inode:
6348                 inode_unlock(inode);
6349         }
6350         return err;
6351 }
6352
6353 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6354                              unsigned int flags)
6355 {
6356         int err;
6357         struct inode *qf_inode;
6358         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6359                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6360                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6361                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6362         };
6363
6364         BUG_ON(!ext4_has_feature_quota(sb));
6365
6366         if (!qf_inums[type])
6367                 return -EPERM;
6368
6369         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6370         if (IS_ERR(qf_inode)) {
6371                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6372                 return PTR_ERR(qf_inode);
6373         }
6374
6375         /* Don't account quota for quota files to avoid recursion */
6376         qf_inode->i_flags |= S_NOQUOTA;
6377         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6378         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6379         if (err)
6380                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6381         iput(qf_inode);
6382
6383         return err;
6384 }
6385
6386 /* Enable usage tracking for all quota types. */
6387 static int ext4_enable_quotas(struct super_block *sb)
6388 {
6389         int type, err = 0;
6390         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6391                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6392                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6393                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6394         };
6395         bool quota_mopt[EXT4_MAXQUOTAS] = {
6396                 test_opt(sb, USRQUOTA),
6397                 test_opt(sb, GRPQUOTA),
6398                 test_opt(sb, PRJQUOTA),
6399         };
6400
6401         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6402         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6403                 if (qf_inums[type]) {
6404                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6405                                 DQUOT_USAGE_ENABLED |
6406                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6407                         if (err) {
6408                                 ext4_warning(sb,
6409                                         "Failed to enable quota tracking "
6410                                         "(type=%d, err=%d). Please run "
6411                                         "e2fsck to fix.", type, err);
6412                                 for (type--; type >= 0; type--)
6413                                         dquot_quota_off(sb, type);
6414
6415                                 return err;
6416                         }
6417                 }
6418         }
6419         return 0;
6420 }
6421
6422 static int ext4_quota_off(struct super_block *sb, int type)
6423 {
6424         struct inode *inode = sb_dqopt(sb)->files[type];
6425         handle_t *handle;
6426         int err;
6427
6428         /* Force all delayed allocation blocks to be allocated.
6429          * Caller already holds s_umount sem */
6430         if (test_opt(sb, DELALLOC))
6431                 sync_filesystem(sb);
6432
6433         if (!inode || !igrab(inode))
6434                 goto out;
6435
6436         err = dquot_quota_off(sb, type);
6437         if (err || ext4_has_feature_quota(sb))
6438                 goto out_put;
6439
6440         inode_lock(inode);
6441         /*
6442          * Update modification times of quota files when userspace can
6443          * start looking at them. If we fail, we return success anyway since
6444          * this is not a hard failure and quotas are already disabled.
6445          */
6446         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6447         if (IS_ERR(handle)) {
6448                 err = PTR_ERR(handle);
6449                 goto out_unlock;
6450         }
6451         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6452         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6453         inode->i_mtime = inode->i_ctime = current_time(inode);
6454         err = ext4_mark_inode_dirty(handle, inode);
6455         ext4_journal_stop(handle);
6456 out_unlock:
6457         inode_unlock(inode);
6458 out_put:
6459         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6460         iput(inode);
6461         return err;
6462 out:
6463         return dquot_quota_off(sb, type);
6464 }
6465
6466 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6467  * acquiring the locks... As quota files are never truncated and quota code
6468  * itself serializes the operations (and no one else should touch the files)
6469  * we don't have to be afraid of races */
6470 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6471                                size_t len, loff_t off)
6472 {
6473         struct inode *inode = sb_dqopt(sb)->files[type];
6474         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6475         int offset = off & (sb->s_blocksize - 1);
6476         int tocopy;
6477         size_t toread;
6478         struct buffer_head *bh;
6479         loff_t i_size = i_size_read(inode);
6480
6481         if (off > i_size)
6482                 return 0;
6483         if (off+len > i_size)
6484                 len = i_size-off;
6485         toread = len;
6486         while (toread > 0) {
6487                 tocopy = sb->s_blocksize - offset < toread ?
6488                                 sb->s_blocksize - offset : toread;
6489                 bh = ext4_bread(NULL, inode, blk, 0);
6490                 if (IS_ERR(bh))
6491                         return PTR_ERR(bh);
6492                 if (!bh)        /* A hole? */
6493                         memset(data, 0, tocopy);
6494                 else
6495                         memcpy(data, bh->b_data+offset, tocopy);
6496                 brelse(bh);
6497                 offset = 0;
6498                 toread -= tocopy;
6499                 data += tocopy;
6500                 blk++;
6501         }
6502         return len;
6503 }
6504
6505 /* Write to quotafile (we know the transaction is already started and has
6506  * enough credits) */
6507 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6508                                 const char *data, size_t len, loff_t off)
6509 {
6510         struct inode *inode = sb_dqopt(sb)->files[type];
6511         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6512         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6513         int retries = 0;
6514         struct buffer_head *bh;
6515         handle_t *handle = journal_current_handle();
6516
6517         if (EXT4_SB(sb)->s_journal && !handle) {
6518                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6519                         " cancelled because transaction is not started",
6520                         (unsigned long long)off, (unsigned long long)len);
6521                 return -EIO;
6522         }
6523         /*
6524          * Since we account only one data block in transaction credits,
6525          * then it is impossible to cross a block boundary.
6526          */
6527         if (sb->s_blocksize - offset < len) {
6528                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6529                         " cancelled because not block aligned",
6530                         (unsigned long long)off, (unsigned long long)len);
6531                 return -EIO;
6532         }
6533
6534         do {
6535                 bh = ext4_bread(handle, inode, blk,
6536                                 EXT4_GET_BLOCKS_CREATE |
6537                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6538         } while (PTR_ERR(bh) == -ENOSPC &&
6539                  ext4_should_retry_alloc(inode->i_sb, &retries));
6540         if (IS_ERR(bh))
6541                 return PTR_ERR(bh);
6542         if (!bh)
6543                 goto out;
6544         BUFFER_TRACE(bh, "get write access");
6545         err = ext4_journal_get_write_access(handle, bh);
6546         if (err) {
6547                 brelse(bh);
6548                 return err;
6549         }
6550         lock_buffer(bh);
6551         memcpy(bh->b_data+offset, data, len);
6552         flush_dcache_page(bh->b_page);
6553         unlock_buffer(bh);
6554         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6555         brelse(bh);
6556 out:
6557         if (inode->i_size < off + len) {
6558                 i_size_write(inode, off + len);
6559                 EXT4_I(inode)->i_disksize = inode->i_size;
6560                 err2 = ext4_mark_inode_dirty(handle, inode);
6561                 if (unlikely(err2 && !err))
6562                         err = err2;
6563         }
6564         return err ? err : len;
6565 }
6566 #endif
6567
6568 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6569                        const char *dev_name, void *data)
6570 {
6571         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6572 }
6573
6574 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6575 static inline void register_as_ext2(void)
6576 {
6577         int err = register_filesystem(&ext2_fs_type);
6578         if (err)
6579                 printk(KERN_WARNING
6580                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6581 }
6582
6583 static inline void unregister_as_ext2(void)
6584 {
6585         unregister_filesystem(&ext2_fs_type);
6586 }
6587
6588 static inline int ext2_feature_set_ok(struct super_block *sb)
6589 {
6590         if (ext4_has_unknown_ext2_incompat_features(sb))
6591                 return 0;
6592         if (sb_rdonly(sb))
6593                 return 1;
6594         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6595                 return 0;
6596         return 1;
6597 }
6598 #else
6599 static inline void register_as_ext2(void) { }
6600 static inline void unregister_as_ext2(void) { }
6601 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6602 #endif
6603
6604 static inline void register_as_ext3(void)
6605 {
6606         int err = register_filesystem(&ext3_fs_type);
6607         if (err)
6608                 printk(KERN_WARNING
6609                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6610 }
6611
6612 static inline void unregister_as_ext3(void)
6613 {
6614         unregister_filesystem(&ext3_fs_type);
6615 }
6616
6617 static inline int ext3_feature_set_ok(struct super_block *sb)
6618 {
6619         if (ext4_has_unknown_ext3_incompat_features(sb))
6620                 return 0;
6621         if (!ext4_has_feature_journal(sb))
6622                 return 0;
6623         if (sb_rdonly(sb))
6624                 return 1;
6625         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6626                 return 0;
6627         return 1;
6628 }
6629
6630 static struct file_system_type ext4_fs_type = {
6631         .owner          = THIS_MODULE,
6632         .name           = "ext4",
6633         .mount          = ext4_mount,
6634         .kill_sb        = kill_block_super,
6635         .fs_flags       = FS_REQUIRES_DEV,
6636 };
6637 MODULE_ALIAS_FS("ext4");
6638
6639 /* Shared across all ext4 file systems */
6640 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6641
6642 static int __init ext4_init_fs(void)
6643 {
6644         int i, err;
6645
6646         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6647         ext4_li_info = NULL;
6648         mutex_init(&ext4_li_mtx);
6649
6650         /* Build-time check for flags consistency */
6651         ext4_check_flag_values();
6652
6653         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6654                 init_waitqueue_head(&ext4__ioend_wq[i]);
6655
6656         err = ext4_init_es();
6657         if (err)
6658                 return err;
6659
6660         err = ext4_init_pending();
6661         if (err)
6662                 goto out7;
6663
6664         err = ext4_init_post_read_processing();
6665         if (err)
6666                 goto out6;
6667
6668         err = ext4_init_pageio();
6669         if (err)
6670                 goto out5;
6671
6672         err = ext4_init_system_zone();
6673         if (err)
6674                 goto out4;
6675
6676         err = ext4_init_sysfs();
6677         if (err)
6678                 goto out3;
6679
6680         err = ext4_init_mballoc();
6681         if (err)
6682                 goto out2;
6683         err = init_inodecache();
6684         if (err)
6685                 goto out1;
6686
6687         err = ext4_fc_init_dentry_cache();
6688         if (err)
6689                 goto out05;
6690
6691         register_as_ext3();
6692         register_as_ext2();
6693         err = register_filesystem(&ext4_fs_type);
6694         if (err)
6695                 goto out;
6696
6697         return 0;
6698 out:
6699         unregister_as_ext2();
6700         unregister_as_ext3();
6701 out05:
6702         destroy_inodecache();
6703 out1:
6704         ext4_exit_mballoc();
6705 out2:
6706         ext4_exit_sysfs();
6707 out3:
6708         ext4_exit_system_zone();
6709 out4:
6710         ext4_exit_pageio();
6711 out5:
6712         ext4_exit_post_read_processing();
6713 out6:
6714         ext4_exit_pending();
6715 out7:
6716         ext4_exit_es();
6717
6718         return err;
6719 }
6720
6721 static void __exit ext4_exit_fs(void)
6722 {
6723         ext4_destroy_lazyinit_thread();
6724         unregister_as_ext2();
6725         unregister_as_ext3();
6726         unregister_filesystem(&ext4_fs_type);
6727         destroy_inodecache();
6728         ext4_exit_mballoc();
6729         ext4_exit_sysfs();
6730         ext4_exit_system_zone();
6731         ext4_exit_pageio();
6732         ext4_exit_post_read_processing();
6733         ext4_exit_es();
6734         ext4_exit_pending();
6735 }
6736
6737 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6738 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6739 MODULE_LICENSE("GPL");
6740 MODULE_SOFTDEP("pre: crc32c");
6741 module_init(ext4_init_fs)
6742 module_exit(ext4_exit_fs)