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