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 ([email protected])
   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 ([email protected]), 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/uaccess.h>
  43 #include <linux/iversion.h>
  44 #include <linux/unicode.h>
  45 #include <linux/part_stat.h>
  46 #include <linux/kthread.h>
  47 #include <linux/freezer.h>
  48 #include <linux/fsnotify.h>
  49 #include <linux/fs_context.h>
  50 #include <linux/fs_parser.h>
  51
  52 #include "ext4.h"
  53 #include "ext4_extents.h"       /* Needed for trace points definition */
  54 #include "ext4_jbd2.h"
  55 #include "xattr.h"
  56 #include "acl.h"
  57 #include "mballoc.h"
  58 #include "fsmap.h"
  59
  60 #define CREATE_TRACE_POINTS
  61 #include <trace/events/ext4.h>
  62
  63 static struct ext4_lazy_init *ext4_li_info;
  64 static DEFINE_MUTEX(ext4_li_mtx);
  65 static struct ratelimit_state ext4_mount_msg_ratelimit;
  66
  67 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  68                              unsigned long journal_devnum);
  69 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  70 static void ext4_update_super(struct super_block *sb);
  71 static int ext4_commit_super(struct super_block *sb);
  72 static int ext4_mark_recovery_complete(struct super_block *sb,
  73                                         struct ext4_super_block *es);
  74 static int ext4_clear_journal_err(struct super_block *sb,
  75                                   struct ext4_super_block *es);
  76 static int ext4_sync_fs(struct super_block *sb, int wait);
  77 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  78 static int ext4_unfreeze(struct super_block *sb);
  79 static int ext4_freeze(struct super_block *sb);
  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 void ext4_destroy_lazyinit_thread(void);
  83 static void ext4_unregister_li_request(struct super_block *sb);
  84 static void ext4_clear_request_list(void);
  85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  86                                             unsigned int journal_inum);
  87 static int ext4_validate_options(struct fs_context *fc);
  88 static int ext4_check_opt_consistency(struct fs_context *fc,
  89                                       struct super_block *sb);
  90 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb);
  91 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param);
  92 static int ext4_get_tree(struct fs_context *fc);
  93 static int ext4_reconfigure(struct fs_context *fc);
  94 static void ext4_fc_free(struct fs_context *fc);
  95 static int ext4_init_fs_context(struct fs_context *fc);
  96 static void ext4_kill_sb(struct super_block *sb);
  97 static const struct fs_parameter_spec ext4_param_specs[];
  98
  99 /*
 100  * Lock ordering
 101  *
 102  * page fault path:
 103  * mmap_lock -> sb_start_pagefault -> invalidate_lock (r) -> transaction start
 104  *   -> page lock -> i_data_sem (rw)
 105  *
 106  * buffered write path:
 107  * sb_start_write -> i_mutex -> mmap_lock
 108  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 109  *   i_data_sem (rw)
 110  *
 111  * truncate:
 112  * sb_start_write -> i_mutex -> invalidate_lock (w) -> i_mmap_rwsem (w) ->
 113  *   page lock
 114  * sb_start_write -> i_mutex -> invalidate_lock (w) -> transaction start ->
 115  *   i_data_sem (rw)
 116  *
 117  * direct IO:
 118  * sb_start_write -> i_mutex -> mmap_lock
 119  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 120  *
 121  * writepages:
 122  * transaction start -> page lock(s) -> i_data_sem (rw)
 123  */
 124
 125 static const struct fs_context_operations ext4_context_ops = {
 126         .parse_param    = ext4_parse_param,
 127         .get_tree       = ext4_get_tree,
 128         .reconfigure    = ext4_reconfigure,
 129         .free           = ext4_fc_free,
 130 };
 131
 132
 133 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 134 static struct file_system_type ext2_fs_type = {
 135         .owner                  = THIS_MODULE,
 136         .name                   = "ext2",
 137         .init_fs_context        = ext4_init_fs_context,
 138         .parameters             = ext4_param_specs,
 139         .kill_sb                = ext4_kill_sb,
 140         .fs_flags               = FS_REQUIRES_DEV,
 141 };
 142 MODULE_ALIAS_FS("ext2");
 143 MODULE_ALIAS("ext2");
 144 #define IS_EXT2_SB(sb) ((sb)->s_type == &ext2_fs_type)
 145 #else
 146 #define IS_EXT2_SB(sb) (0)
 147 #endif
 148
 149
 150 static struct file_system_type ext3_fs_type = {
 151         .owner                  = THIS_MODULE,
 152         .name                   = "ext3",
 153         .init_fs_context        = ext4_init_fs_context,
 154         .parameters             = ext4_param_specs,
 155         .kill_sb                = ext4_kill_sb,
 156         .fs_flags               = FS_REQUIRES_DEV,
 157 };
 158 MODULE_ALIAS_FS("ext3");
 159 MODULE_ALIAS("ext3");
 160 #define IS_EXT3_SB(sb) ((sb)->s_type == &ext3_fs_type)
 161
 162
 163 static inline void __ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
 164                                   bh_end_io_t *end_io, bool simu_fail)
 165 {
 166         if (simu_fail) {
 167                 clear_buffer_uptodate(bh);
 168                 unlock_buffer(bh);
 169                 return;
 170         }
 171
 172         /*
 173          * buffer's verified bit is no longer valid after reading from
 174          * disk again due to write out error, clear it to make sure we
 175          * recheck the buffer contents.
 176          */
 177         clear_buffer_verified(bh);
 178
 179         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
 180         get_bh(bh);
 181         submit_bh(REQ_OP_READ | op_flags, bh);
 182 }
 183
 184 void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
 185                          bh_end_io_t *end_io, bool simu_fail)
 186 {
 187         BUG_ON(!buffer_locked(bh));
 188
 189         if (ext4_buffer_uptodate(bh)) {
 190                 unlock_buffer(bh);
 191                 return;
 192         }
 193         __ext4_read_bh(bh, op_flags, end_io, simu_fail);
 194 }
 195
 196 int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
 197                  bh_end_io_t *end_io, bool simu_fail)
 198 {
 199         BUG_ON(!buffer_locked(bh));
 200
 201         if (ext4_buffer_uptodate(bh)) {
 202                 unlock_buffer(bh);
 203                 return 0;
 204         }
 205
 206         __ext4_read_bh(bh, op_flags, end_io, simu_fail);
 207
 208         wait_on_buffer(bh);
 209         if (buffer_uptodate(bh))
 210                 return 0;
 211         return -EIO;
 212 }
 213
 214 int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait)
 215 {
 216         lock_buffer(bh);
 217         if (!wait) {
 218                 ext4_read_bh_nowait(bh, op_flags, NULL, false);
 219                 return 0;
 220         }
 221         return ext4_read_bh(bh, op_flags, NULL, false);
 222 }
 223
 224 /*
 225  * This works like __bread_gfp() except it uses ERR_PTR for error
 226  * returns.  Currently with sb_bread it's impossible to distinguish
 227  * between ENOMEM and EIO situations (since both result in a NULL
 228  * return.
 229  */
 230 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 231                                                sector_t block,
 232                                                blk_opf_t op_flags, gfp_t gfp)
 233 {
 234         struct buffer_head *bh;
 235         int ret;
 236
 237         bh = sb_getblk_gfp(sb, block, gfp);
 238         if (bh == NULL)
 239                 return ERR_PTR(-ENOMEM);
 240         if (ext4_buffer_uptodate(bh))
 241                 return bh;
 242
 243         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
 244         if (ret) {
 245                 put_bh(bh);
 246                 return ERR_PTR(ret);
 247         }
 248         return bh;
 249 }
 250
 251 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 252                                    blk_opf_t op_flags)
 253 {
 254         gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_mapping,
 255                         ~__GFP_FS) | __GFP_MOVABLE;
 256
 257         return __ext4_sb_bread_gfp(sb, block, op_flags, gfp);
 258 }
 259
 260 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 261                                             sector_t block)
 262 {
 263         gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_mapping,
 264                         ~__GFP_FS);
 265
 266         return __ext4_sb_bread_gfp(sb, block, 0, gfp);
 267 }
 268
 269 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
 270 {
 271         struct buffer_head *bh = bdev_getblk(sb->s_bdev, block,
 272                         sb->s_blocksize, GFP_NOWAIT | __GFP_NOWARN);
 273
 274         if (likely(bh)) {
 275                 if (trylock_buffer(bh))
 276                         ext4_read_bh_nowait(bh, REQ_RAHEAD, NULL, false);
 277                 brelse(bh);
 278         }
 279 }
 280
 281 static int ext4_verify_csum_type(struct super_block *sb,
 282                                  struct ext4_super_block *es)
 283 {
 284         if (!ext4_has_feature_metadata_csum(sb))
 285                 return 1;
 286
 287         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 288 }
 289
 290 __le32 ext4_superblock_csum(struct super_block *sb,
 291                             struct ext4_super_block *es)
 292 {
 293         struct ext4_sb_info *sbi = EXT4_SB(sb);
 294         int offset = offsetof(struct ext4_super_block, s_checksum);
 295         __u32 csum;
 296
 297         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 298
 299         return cpu_to_le32(csum);
 300 }
 301
 302 static int ext4_superblock_csum_verify(struct super_block *sb,
 303                                        struct ext4_super_block *es)
 304 {
 305         if (!ext4_has_metadata_csum(sb))
 306                 return 1;
 307
 308         return es->s_checksum == ext4_superblock_csum(sb, es);
 309 }
 310
 311 void ext4_superblock_csum_set(struct super_block *sb)
 312 {
 313         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 314
 315         if (!ext4_has_metadata_csum(sb))
 316                 return;
 317
 318         es->s_checksum = ext4_superblock_csum(sb, es);
 319 }
 320
 321 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 322                                struct ext4_group_desc *bg)
 323 {
 324         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 325                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 326                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 327 }
 328
 329 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 330                                struct ext4_group_desc *bg)
 331 {
 332         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 333                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 334                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 335 }
 336
 337 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 338                               struct ext4_group_desc *bg)
 339 {
 340         return le32_to_cpu(bg->bg_inode_table_lo) |
 341                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 342                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 343 }
 344
 345 __u32 ext4_free_group_clusters(struct super_block *sb,
 346                                struct ext4_group_desc *bg)
 347 {
 348         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 349                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 350                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 351 }
 352
 353 __u32 ext4_free_inodes_count(struct super_block *sb,
 354                               struct ext4_group_desc *bg)
 355 {
 356         return le16_to_cpu(READ_ONCE(bg->bg_free_inodes_count_lo)) |
 357                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 358                  (__u32)le16_to_cpu(READ_ONCE(bg->bg_free_inodes_count_hi)) << 16 : 0);
 359 }
 360
 361 __u32 ext4_used_dirs_count(struct super_block *sb,
 362                               struct ext4_group_desc *bg)
 363 {
 364         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 365                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 366                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 367 }
 368
 369 __u32 ext4_itable_unused_count(struct super_block *sb,
 370                               struct ext4_group_desc *bg)
 371 {
 372         return le16_to_cpu(bg->bg_itable_unused_lo) |
 373                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 374                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 375 }
 376
 377 void ext4_block_bitmap_set(struct super_block *sb,
 378                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 379 {
 380         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 381         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 382                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 383 }
 384
 385 void ext4_inode_bitmap_set(struct super_block *sb,
 386                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 387 {
 388         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 389         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 390                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 391 }
 392
 393 void ext4_inode_table_set(struct super_block *sb,
 394                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 395 {
 396         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 397         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 398                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 399 }
 400
 401 void ext4_free_group_clusters_set(struct super_block *sb,
 402                                   struct ext4_group_desc *bg, __u32 count)
 403 {
 404         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 405         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 406                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 407 }
 408
 409 void ext4_free_inodes_set(struct super_block *sb,
 410                           struct ext4_group_desc *bg, __u32 count)
 411 {
 412         WRITE_ONCE(bg->bg_free_inodes_count_lo, cpu_to_le16((__u16)count));
 413         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 414                 WRITE_ONCE(bg->bg_free_inodes_count_hi, cpu_to_le16(count >> 16));
 415 }
 416
 417 void ext4_used_dirs_set(struct super_block *sb,
 418                           struct ext4_group_desc *bg, __u32 count)
 419 {
 420         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 421         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 422                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 423 }
 424
 425 void ext4_itable_unused_set(struct super_block *sb,
 426                           struct ext4_group_desc *bg, __u32 count)
 427 {
 428         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 429         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 430                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 431 }
 432
 433 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi, time64_t now)
 434 {
 435         now = clamp_val(now, 0, (1ull << 40) - 1);
 436
 437         *lo = cpu_to_le32(lower_32_bits(now));
 438         *hi = upper_32_bits(now);
 439 }
 440
 441 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 442 {
 443         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 444 }
 445 #define ext4_update_tstamp(es, tstamp) \
 446         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi, \
 447                              ktime_get_real_seconds())
 448 #define ext4_get_tstamp(es, tstamp) \
 449         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 450
 451 #define EXT4_SB_REFRESH_INTERVAL_SEC (3600) /* seconds (1 hour) */
 452 #define EXT4_SB_REFRESH_INTERVAL_KB (16384) /* kilobytes (16MB) */
 453
 454 /*
 455  * The ext4_maybe_update_superblock() function checks and updates the
 456  * superblock if needed.
 457  *
 458  * This function is designed to update the on-disk superblock only under
 459  * certain conditions to prevent excessive disk writes and unnecessary
 460  * waking of the disk from sleep. The superblock will be updated if:
 461  * 1. More than an hour has passed since the last superblock update, and
 462  * 2. More than 16MB have been written since the last superblock update.
 463  *
 464  * @sb: The superblock
 465  */
 466 static void ext4_maybe_update_superblock(struct super_block *sb)
 467 {
 468         struct ext4_sb_info *sbi = EXT4_SB(sb);
 469         struct ext4_super_block *es = sbi->s_es;
 470         journal_t *journal = sbi->s_journal;
 471         time64_t now;
 472         __u64 last_update;
 473         __u64 lifetime_write_kbytes;
 474         __u64 diff_size;
 475
 476         if (sb_rdonly(sb) || !(sb->s_flags & SB_ACTIVE) ||
 477             !journal || (journal->j_flags & JBD2_UNMOUNT))
 478                 return;
 479
 480         now = ktime_get_real_seconds();
 481         last_update = ext4_get_tstamp(es, s_wtime);
 482
 483         if (likely(now - last_update < EXT4_SB_REFRESH_INTERVAL_SEC))
 484                 return;
 485
 486         lifetime_write_kbytes = sbi->s_kbytes_written +
 487                 ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
 488                   sbi->s_sectors_written_start) >> 1);
 489
 490         /* Get the number of kilobytes not written to disk to account
 491          * for statistics and compare with a multiple of 16 MB. This
 492          * is used to determine when the next superblock commit should
 493          * occur (i.e. not more often than once per 16MB if there was
 494          * less written in an hour).
 495          */
 496         diff_size = lifetime_write_kbytes - le64_to_cpu(es->s_kbytes_written);
 497
 498         if (diff_size > EXT4_SB_REFRESH_INTERVAL_KB)
 499                 schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
 500 }
 501
 502 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 503 {
 504         struct super_block              *sb = journal->j_private;
 505         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 506         int                             error = is_journal_aborted(journal);
 507         struct ext4_journal_cb_entry    *jce;
 508
 509         BUG_ON(txn->t_state == T_FINISHED);
 510
 511         ext4_process_freed_data(sb, txn->t_tid);
 512         ext4_maybe_update_superblock(sb);
 513
 514         spin_lock(&sbi->s_md_lock);
 515         while (!list_empty(&txn->t_private_list)) {
 516                 jce = list_entry(txn->t_private_list.next,
 517                                  struct ext4_journal_cb_entry, jce_list);
 518                 list_del_init(&jce->jce_list);
 519                 spin_unlock(&sbi->s_md_lock);
 520                 jce->jce_func(sb, jce, error);
 521                 spin_lock(&sbi->s_md_lock);
 522         }
 523         spin_unlock(&sbi->s_md_lock);
 524 }
 525
 526 /*
 527  * This writepage callback for write_cache_pages()
 528  * takes care of a few cases after page cleaning.
 529  *
 530  * write_cache_pages() already checks for dirty pages
 531  * and calls clear_page_dirty_for_io(), which we want,
 532  * to write protect the pages.
 533  *
 534  * However, we may have to redirty a page (see below.)
 535  */
 536 static int ext4_journalled_writepage_callback(struct folio *folio,
 537                                               struct writeback_control *wbc,
 538                                               void *data)
 539 {
 540         transaction_t *transaction = (transaction_t *) data;
 541         struct buffer_head *bh, *head;
 542         struct journal_head *jh;
 543
 544         bh = head = folio_buffers(folio);
 545         do {
 546                 /*
 547                  * We have to redirty a page in these cases:
 548                  * 1) If buffer is dirty, it means the page was dirty because it
 549                  * contains a buffer that needs checkpointing. So the dirty bit
 550                  * needs to be preserved so that checkpointing writes the buffer
 551                  * properly.
 552                  * 2) If buffer is not part of the committing transaction
 553                  * (we may have just accidentally come across this buffer because
 554                  * inode range tracking is not exact) or if the currently running
 555                  * transaction already contains this buffer as well, dirty bit
 556                  * needs to be preserved so that the buffer gets writeprotected
 557                  * properly on running transaction's commit.
 558                  */
 559                 jh = bh2jh(bh);
 560                 if (buffer_dirty(bh) ||
 561                     (jh && (jh->b_transaction != transaction ||
 562                             jh->b_next_transaction))) {
 563                         folio_redirty_for_writepage(wbc, folio);
 564                         goto out;
 565                 }
 566         } while ((bh = bh->b_this_page) != head);
 567
 568 out:
 569         return AOP_WRITEPAGE_ACTIVATE;
 570 }
 571
 572 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
 573 {
 574         struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
 575         struct writeback_control wbc = {
 576                 .sync_mode =  WB_SYNC_ALL,
 577                 .nr_to_write = LONG_MAX,
 578                 .range_start = jinode->i_dirty_start,
 579                 .range_end = jinode->i_dirty_end,
 580         };
 581
 582         return write_cache_pages(mapping, &wbc,
 583                                  ext4_journalled_writepage_callback,
 584                                  jinode->i_transaction);
 585 }
 586
 587 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
 588 {
 589         int ret;
 590
 591         if (ext4_should_journal_data(jinode->i_vfs_inode))
 592                 ret = ext4_journalled_submit_inode_data_buffers(jinode);
 593         else
 594                 ret = ext4_normal_submit_inode_data_buffers(jinode);
 595         return ret;
 596 }
 597
 598 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
 599 {
 600         int ret = 0;
 601
 602         if (!ext4_should_journal_data(jinode->i_vfs_inode))
 603                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
 604
 605         return ret;
 606 }
 607
 608 static bool system_going_down(void)
 609 {
 610         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 611                 || system_state == SYSTEM_RESTART;
 612 }
 613
 614 struct ext4_err_translation {
 615         int code;
 616         int errno;
 617 };
 618
 619 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
 620
 621 static struct ext4_err_translation err_translation[] = {
 622         EXT4_ERR_TRANSLATE(EIO),
 623         EXT4_ERR_TRANSLATE(ENOMEM),
 624         EXT4_ERR_TRANSLATE(EFSBADCRC),
 625         EXT4_ERR_TRANSLATE(EFSCORRUPTED),
 626         EXT4_ERR_TRANSLATE(ENOSPC),
 627         EXT4_ERR_TRANSLATE(ENOKEY),
 628         EXT4_ERR_TRANSLATE(EROFS),
 629         EXT4_ERR_TRANSLATE(EFBIG),
 630         EXT4_ERR_TRANSLATE(EEXIST),
 631         EXT4_ERR_TRANSLATE(ERANGE),
 632         EXT4_ERR_TRANSLATE(EOVERFLOW),
 633         EXT4_ERR_TRANSLATE(EBUSY),
 634         EXT4_ERR_TRANSLATE(ENOTDIR),
 635         EXT4_ERR_TRANSLATE(ENOTEMPTY),
 636         EXT4_ERR_TRANSLATE(ESHUTDOWN),
 637         EXT4_ERR_TRANSLATE(EFAULT),
 638 };
 639
 640 static int ext4_errno_to_code(int errno)
 641 {
 642         int i;
 643
 644         for (i = 0; i < ARRAY_SIZE(err_translation); i++)
 645                 if (err_translation[i].errno == errno)
 646                         return err_translation[i].code;
 647         return EXT4_ERR_UNKNOWN;
 648 }
 649
 650 static void save_error_info(struct super_block *sb, int error,
 651                             __u32 ino, __u64 block,
 652                             const char *func, unsigned int line)
 653 {
 654         struct ext4_sb_info *sbi = EXT4_SB(sb);
 655
 656         /* We default to EFSCORRUPTED error... */
 657         if (error == 0)
 658                 error = EFSCORRUPTED;
 659
 660         spin_lock(&sbi->s_error_lock);
 661         sbi->s_add_error_count++;
 662         sbi->s_last_error_code = error;
 663         sbi->s_last_error_line = line;
 664         sbi->s_last_error_ino = ino;
 665         sbi->s_last_error_block = block;
 666         sbi->s_last_error_func = func;
 667         sbi->s_last_error_time = ktime_get_real_seconds();
 668         if (!sbi->s_first_error_time) {
 669                 sbi->s_first_error_code = error;
 670                 sbi->s_first_error_line = line;
 671                 sbi->s_first_error_ino = ino;
 672                 sbi->s_first_error_block = block;
 673                 sbi->s_first_error_func = func;
 674                 sbi->s_first_error_time = sbi->s_last_error_time;
 675         }
 676         spin_unlock(&sbi->s_error_lock);
 677 }
 678
 679 /* Deal with the reporting of failure conditions on a filesystem such as
 680  * inconsistencies detected or read IO failures.
 681  *
 682  * On ext2, we can store the error state of the filesystem in the
 683  * superblock.  That is not possible on ext4, because we may have other
 684  * write ordering constraints on the superblock which prevent us from
 685  * writing it out straight away; and given that the journal is about to
 686  * be aborted, we can't rely on the current, or future, transactions to
 687  * write out the superblock safely.
 688  *
 689  * We'll just use the jbd2_journal_abort() error code to record an error in
 690  * the journal instead.  On recovery, the journal will complain about
 691  * that error until we've noted it down and cleared it.
 692  *
 693  * If force_ro is set, we unconditionally force the filesystem into an
 694  * ABORT|READONLY state, unless the error response on the fs has been set to
 695  * panic in which case we take the easy way out and panic immediately. This is
 696  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
 697  * at a critical moment in log management.
 698  */
 699 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
 700                               __u32 ino, __u64 block,
 701                               const char *func, unsigned int line)
 702 {
 703         journal_t *journal = EXT4_SB(sb)->s_journal;
 704         bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
 705
 706         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 707         if (test_opt(sb, WARN_ON_ERROR))
 708                 WARN_ON_ONCE(1);
 709
 710         if (!continue_fs && !sb_rdonly(sb)) {
 711                 set_bit(EXT4_FLAGS_SHUTDOWN, &EXT4_SB(sb)->s_ext4_flags);
 712                 if (journal)
 713                         jbd2_journal_abort(journal, -EIO);
 714         }
 715
 716         if (!bdev_read_only(sb->s_bdev)) {
 717                 save_error_info(sb, error, ino, block, func, line);
 718                 /*
 719                  * In case the fs should keep running, we need to writeout
 720                  * superblock through the journal. Due to lock ordering
 721                  * constraints, it may not be safe to do it right here so we
 722                  * defer superblock flushing to a workqueue.
 723                  */
 724                 if (continue_fs && journal)
 725                         schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
 726                 else
 727                         ext4_commit_super(sb);
 728         }
 729
 730         /*
 731          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 732          * could panic during 'reboot -f' as the underlying device got already
 733          * disabled.
 734          */
 735         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 736                 panic("EXT4-fs (device %s): panic forced after error\n",
 737                         sb->s_id);
 738         }
 739
 740         if (sb_rdonly(sb) || continue_fs)
 741                 return;
 742
 743         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 744         /*
 745          * EXT4_FLAGS_SHUTDOWN was set which stops all filesystem
 746          * modifications. We don't set SB_RDONLY because that requires
 747          * sb->s_umount semaphore and setting it without proper remount
 748          * procedure is confusing code such as freeze_super() leading to
 749          * deadlocks and other problems.
 750          */
 751 }
 752
 753 static void update_super_work(struct work_struct *work)
 754 {
 755         struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
 756                                                 s_sb_upd_work);
 757         journal_t *journal = sbi->s_journal;
 758         handle_t *handle;
 759
 760         /*
 761          * If the journal is still running, we have to write out superblock
 762          * through the journal to avoid collisions of other journalled sb
 763          * updates.
 764          *
 765          * We use directly jbd2 functions here to avoid recursing back into
 766          * ext4 error handling code during handling of previous errors.
 767          */
 768         if (!sb_rdonly(sbi->s_sb) && journal) {
 769                 struct buffer_head *sbh = sbi->s_sbh;
 770                 bool call_notify_err = false;
 771
 772                 handle = jbd2_journal_start(journal, 1);
 773                 if (IS_ERR(handle))
 774                         goto write_directly;
 775                 if (jbd2_journal_get_write_access(handle, sbh)) {
 776                         jbd2_journal_stop(handle);
 777                         goto write_directly;
 778                 }
 779
 780                 if (sbi->s_add_error_count > 0)
 781                         call_notify_err = true;
 782
 783                 ext4_update_super(sbi->s_sb);
 784                 if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
 785                         ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
 786                                  "superblock detected");
 787                         clear_buffer_write_io_error(sbh);
 788                         set_buffer_uptodate(sbh);
 789                 }
 790
 791                 if (jbd2_journal_dirty_metadata(handle, sbh)) {
 792                         jbd2_journal_stop(handle);
 793                         goto write_directly;
 794                 }
 795                 jbd2_journal_stop(handle);
 796
 797                 if (call_notify_err)
 798                         ext4_notify_error_sysfs(sbi);
 799
 800                 return;
 801         }
 802 write_directly:
 803         /*
 804          * Write through journal failed. Write sb directly to get error info
 805          * out and hope for the best.
 806          */
 807         ext4_commit_super(sbi->s_sb);
 808         ext4_notify_error_sysfs(sbi);
 809 }
 810
 811 #define ext4_error_ratelimit(sb)                                        \
 812                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 813                              "EXT4-fs error")
 814
 815 void __ext4_error(struct super_block *sb, const char *function,
 816                   unsigned int line, bool force_ro, int error, __u64 block,
 817                   const char *fmt, ...)
 818 {
 819         struct va_format vaf;
 820         va_list args;
 821
 822         if (unlikely(ext4_forced_shutdown(sb)))
 823                 return;
 824
 825         trace_ext4_error(sb, function, line);
 826         if (ext4_error_ratelimit(sb)) {
 827                 va_start(args, fmt);
 828                 vaf.fmt = fmt;
 829                 vaf.va = &args;
 830                 printk(KERN_CRIT
 831                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 832                        sb->s_id, function, line, current->comm, &vaf);
 833                 va_end(args);
 834         }
 835         fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
 836
 837         ext4_handle_error(sb, force_ro, error, 0, block, function, line);
 838 }
 839
 840 void __ext4_error_inode(struct inode *inode, const char *function,
 841                         unsigned int line, ext4_fsblk_t block, int error,
 842                         const char *fmt, ...)
 843 {
 844         va_list args;
 845         struct va_format vaf;
 846
 847         if (unlikely(ext4_forced_shutdown(inode->i_sb)))
 848                 return;
 849
 850         trace_ext4_error(inode->i_sb, function, line);
 851         if (ext4_error_ratelimit(inode->i_sb)) {
 852                 va_start(args, fmt);
 853                 vaf.fmt = fmt;
 854                 vaf.va = &args;
 855                 if (block)
 856                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 857                                "inode #%lu: block %llu: comm %s: %pV\n",
 858                                inode->i_sb->s_id, function, line, inode->i_ino,
 859                                block, current->comm, &vaf);
 860                 else
 861                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 862                                "inode #%lu: comm %s: %pV\n",
 863                                inode->i_sb->s_id, function, line, inode->i_ino,
 864                                current->comm, &vaf);
 865                 va_end(args);
 866         }
 867         fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
 868
 869         ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
 870                           function, line);
 871 }
 872
 873 void __ext4_error_file(struct file *file, const char *function,
 874                        unsigned int line, ext4_fsblk_t block,
 875                        const char *fmt, ...)
 876 {
 877         va_list args;
 878         struct va_format vaf;
 879         struct inode *inode = file_inode(file);
 880         char pathname[80], *path;
 881
 882         if (unlikely(ext4_forced_shutdown(inode->i_sb)))
 883                 return;
 884
 885         trace_ext4_error(inode->i_sb, function, line);
 886         if (ext4_error_ratelimit(inode->i_sb)) {
 887                 path = file_path(file, pathname, sizeof(pathname));
 888                 if (IS_ERR(path))
 889                         path = "(unknown)";
 890                 va_start(args, fmt);
 891                 vaf.fmt = fmt;
 892                 vaf.va = &args;
 893                 if (block)
 894                         printk(KERN_CRIT
 895                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 896                                "block %llu: comm %s: path %s: %pV\n",
 897                                inode->i_sb->s_id, function, line, inode->i_ino,
 898                                block, current->comm, path, &vaf);
 899                 else
 900                         printk(KERN_CRIT
 901                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 902                                "comm %s: path %s: %pV\n",
 903                                inode->i_sb->s_id, function, line, inode->i_ino,
 904                                current->comm, path, &vaf);
 905                 va_end(args);
 906         }
 907         fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
 908
 909         ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
 910                           function, line);
 911 }
 912
 913 const char *ext4_decode_error(struct super_block *sb, int errno,
 914                               char nbuf[16])
 915 {
 916         char *errstr = NULL;
 917
 918         switch (errno) {
 919         case -EFSCORRUPTED:
 920                 errstr = "Corrupt filesystem";
 921                 break;
 922         case -EFSBADCRC:
 923                 errstr = "Filesystem failed CRC";
 924                 break;
 925         case -EIO:
 926                 errstr = "IO failure";
 927                 break;
 928         case -ENOMEM:
 929                 errstr = "Out of memory";
 930                 break;
 931         case -EROFS:
 932                 if (!sb || (EXT4_SB(sb)->s_journal &&
 933                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 934                         errstr = "Journal has aborted";
 935                 else
 936                         errstr = "Readonly filesystem";
 937                 break;
 938         default:
 939                 /* If the caller passed in an extra buffer for unknown
 940                  * errors, textualise them now.  Else we just return
 941                  * NULL. */
 942                 if (nbuf) {
 943                         /* Check for truncated error codes... */
 944                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 945                                 errstr = nbuf;
 946                 }
 947                 break;
 948         }
 949
 950         return errstr;
 951 }
 952
 953 /* __ext4_std_error decodes expected errors from journaling functions
 954  * automatically and invokes the appropriate error response.  */
 955
 956 void __ext4_std_error(struct super_block *sb, const char *function,
 957                       unsigned int line, int errno)
 958 {
 959         char nbuf[16];
 960         const char *errstr;
 961
 962         if (unlikely(ext4_forced_shutdown(sb)))
 963                 return;
 964
 965         /* Special case: if the error is EROFS, and we're not already
 966          * inside a transaction, then there's really no point in logging
 967          * an error. */
 968         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 969                 return;
 970
 971         if (ext4_error_ratelimit(sb)) {
 972                 errstr = ext4_decode_error(sb, errno, nbuf);
 973                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 974                        sb->s_id, function, line, errstr);
 975         }
 976         fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
 977
 978         ext4_handle_error(sb, false, -errno, 0, 0, function, line);
 979 }
 980
 981 void __ext4_msg(struct super_block *sb,
 982                 const char *prefix, const char *fmt, ...)
 983 {
 984         struct va_format vaf;
 985         va_list args;
 986
 987         if (sb) {
 988                 atomic_inc(&EXT4_SB(sb)->s_msg_count);
 989                 if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state),
 990                                   "EXT4-fs"))
 991                         return;
 992         }
 993
 994         va_start(args, fmt);
 995         vaf.fmt = fmt;
 996         vaf.va = &args;
 997         if (sb)
 998                 printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 999         else
1000                 printk("%sEXT4-fs: %pV\n", prefix, &vaf);
1001         va_end(args);
1002 }
1003
1004 static int ext4_warning_ratelimit(struct super_block *sb)
1005 {
1006         atomic_inc(&EXT4_SB(sb)->s_warning_count);
1007         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
1008                             "EXT4-fs warning");
1009 }
1010
1011 void __ext4_warning(struct super_block *sb, const char *function,
1012                     unsigned int line, const char *fmt, ...)
1013 {
1014         struct va_format vaf;
1015         va_list args;
1016
1017         if (!ext4_warning_ratelimit(sb))
1018                 return;
1019
1020         va_start(args, fmt);
1021         vaf.fmt = fmt;
1022         vaf.va = &args;
1023         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
1024                sb->s_id, function, line, &vaf);
1025         va_end(args);
1026 }
1027
1028 void __ext4_warning_inode(const struct inode *inode, const char *function,
1029                           unsigned int line, const char *fmt, ...)
1030 {
1031         struct va_format vaf;
1032         va_list args;
1033
1034         if (!ext4_warning_ratelimit(inode->i_sb))
1035                 return;
1036
1037         va_start(args, fmt);
1038         vaf.fmt = fmt;
1039         vaf.va = &args;
1040         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
1041                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
1042                function, line, inode->i_ino, current->comm, &vaf);
1043         va_end(args);
1044 }
1045
1046 void __ext4_grp_locked_error(const char *function, unsigned int line,
1047                              struct super_block *sb, ext4_group_t grp,
1048                              unsigned long ino, ext4_fsblk_t block,
1049                              const char *fmt, ...)
1050 __releases(bitlock)
1051 __acquires(bitlock)
1052 {
1053         struct va_format vaf;
1054         va_list args;
1055
1056         if (unlikely(ext4_forced_shutdown(sb)))
1057                 return;
1058
1059         trace_ext4_error(sb, function, line);
1060         if (ext4_error_ratelimit(sb)) {
1061                 va_start(args, fmt);
1062                 vaf.fmt = fmt;
1063                 vaf.va = &args;
1064                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1065                        sb->s_id, function, line, grp);
1066                 if (ino)
1067                         printk(KERN_CONT "inode %lu: ", ino);
1068                 if (block)
1069                         printk(KERN_CONT "block %llu:",
1070                                (unsigned long long) block);
1071                 printk(KERN_CONT "%pV\n", &vaf);
1072                 va_end(args);
1073         }
1074
1075         if (test_opt(sb, ERRORS_CONT)) {
1076                 if (test_opt(sb, WARN_ON_ERROR))
1077                         WARN_ON_ONCE(1);
1078                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
1079                 if (!bdev_read_only(sb->s_bdev)) {
1080                         save_error_info(sb, EFSCORRUPTED, ino, block, function,
1081                                         line);
1082                         schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
1083                 }
1084                 return;
1085         }
1086         ext4_unlock_group(sb, grp);
1087         ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1088         /*
1089          * We only get here in the ERRORS_RO case; relocking the group
1090          * may be dangerous, but nothing bad will happen since the
1091          * filesystem will have already been marked read/only and the
1092          * journal has been aborted.  We return 1 as a hint to callers
1093          * who might what to use the return value from
1094          * ext4_grp_locked_error() to distinguish between the
1095          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1096          * aggressively from the ext4 function in question, with a
1097          * more appropriate error code.
1098          */
1099         ext4_lock_group(sb, grp);
1100         return;
1101 }
1102
1103 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1104                                      ext4_group_t group,
1105                                      unsigned int flags)
1106 {
1107         struct ext4_sb_info *sbi = EXT4_SB(sb);
1108         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1109         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1110         int ret;
1111
1112         if (!grp || !gdp)
1113                 return;
1114         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1115                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1116                                             &grp->bb_state);
1117                 if (!ret)
1118                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1119                                            grp->bb_free);
1120         }
1121
1122         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1123                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1124                                             &grp->bb_state);
1125                 if (!ret && gdp) {
1126                         int count;
1127
1128                         count = ext4_free_inodes_count(sb, gdp);
1129                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1130                                            count);
1131                 }
1132         }
1133 }
1134
1135 void ext4_update_dynamic_rev(struct super_block *sb)
1136 {
1137         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1138
1139         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1140                 return;
1141
1142         ext4_warning(sb,
1143                      "updating to rev %d because of new feature flag, "
1144                      "running e2fsck is recommended",
1145                      EXT4_DYNAMIC_REV);
1146
1147         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1148         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1149         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1150         /* leave es->s_feature_*compat flags alone */
1151         /* es->s_uuid will be set by e2fsck if empty */
1152
1153         /*
1154          * The rest of the superblock fields should be zero, and if not it
1155          * means they are likely already in use, so leave them alone.  We
1156          * can leave it up to e2fsck to clean up any inconsistencies there.
1157          */
1158 }
1159
1160 static inline struct inode *orphan_list_entry(struct list_head *l)
1161 {
1162         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1163 }
1164
1165 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1166 {
1167         struct list_head *l;
1168
1169         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1170                  le32_to_cpu(sbi->s_es->s_last_orphan));
1171
1172         printk(KERN_ERR "sb_info orphan list:\n");
1173         list_for_each(l, &sbi->s_orphan) {
1174                 struct inode *inode = orphan_list_entry(l);
1175                 printk(KERN_ERR "  "
1176                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1177                        inode->i_sb->s_id, inode->i_ino, inode,
1178                        inode->i_mode, inode->i_nlink,
1179                        NEXT_ORPHAN(inode));
1180         }
1181 }
1182
1183 #ifdef CONFIG_QUOTA
1184 static int ext4_quota_off(struct super_block *sb, int type);
1185
1186 static inline void ext4_quotas_off(struct super_block *sb, int type)
1187 {
1188         BUG_ON(type > EXT4_MAXQUOTAS);
1189
1190         /* Use our quota_off function to clear inode flags etc. */
1191         for (type--; type >= 0; type--)
1192                 ext4_quota_off(sb, type);
1193 }
1194
1195 /*
1196  * This is a helper function which is used in the mount/remount
1197  * codepaths (which holds s_umount) to fetch the quota file name.
1198  */
1199 static inline char *get_qf_name(struct super_block *sb,
1200                                 struct ext4_sb_info *sbi,
1201                                 int type)
1202 {
1203         return rcu_dereference_protected(sbi->s_qf_names[type],
1204                                          lockdep_is_held(&sb->s_umount));
1205 }
1206 #else
1207 static inline void ext4_quotas_off(struct super_block *sb, int type)
1208 {
1209 }
1210 #endif
1211
1212 static int ext4_percpu_param_init(struct ext4_sb_info *sbi)
1213 {
1214         ext4_fsblk_t block;
1215         int err;
1216
1217         block = ext4_count_free_clusters(sbi->s_sb);
1218         ext4_free_blocks_count_set(sbi->s_es, EXT4_C2B(sbi, block));
1219         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
1220                                   GFP_KERNEL);
1221         if (!err) {
1222                 unsigned long freei = ext4_count_free_inodes(sbi->s_sb);
1223                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
1224                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
1225                                           GFP_KERNEL);
1226         }
1227         if (!err)
1228                 err = percpu_counter_init(&sbi->s_dirs_counter,
1229                                           ext4_count_dirs(sbi->s_sb), GFP_KERNEL);
1230         if (!err)
1231                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
1232                                           GFP_KERNEL);
1233         if (!err)
1234                 err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
1235                                           GFP_KERNEL);
1236         if (!err)
1237                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
1238
1239         if (err)
1240                 ext4_msg(sbi->s_sb, KERN_ERR, "insufficient memory");
1241
1242         return err;
1243 }
1244
1245 static void ext4_percpu_param_destroy(struct ext4_sb_info *sbi)
1246 {
1247         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1248         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1249         percpu_counter_destroy(&sbi->s_dirs_counter);
1250         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1251         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1252         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1253 }
1254
1255 static void ext4_group_desc_free(struct ext4_sb_info *sbi)
1256 {
1257         struct buffer_head **group_desc;
1258         int i;
1259
1260         rcu_read_lock();
1261         group_desc = rcu_dereference(sbi->s_group_desc);
1262         for (i = 0; i < sbi->s_gdb_count; i++)
1263                 brelse(group_desc[i]);
1264         kvfree(group_desc);
1265         rcu_read_unlock();
1266 }
1267
1268 static void ext4_flex_groups_free(struct ext4_sb_info *sbi)
1269 {
1270         struct flex_groups **flex_groups;
1271         int i;
1272
1273         rcu_read_lock();
1274         flex_groups = rcu_dereference(sbi->s_flex_groups);
1275         if (flex_groups) {
1276                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1277                         kvfree(flex_groups[i]);
1278                 kvfree(flex_groups);
1279         }
1280         rcu_read_unlock();
1281 }
1282
1283 static void ext4_put_super(struct super_block *sb)
1284 {
1285         struct ext4_sb_info *sbi = EXT4_SB(sb);
1286         struct ext4_super_block *es = sbi->s_es;
1287         int aborted = 0;
1288         int err;
1289
1290         /*
1291          * Unregister sysfs before destroying jbd2 journal.
1292          * Since we could still access attr_journal_task attribute via sysfs
1293          * path which could have sbi->s_journal->j_task as NULL
1294          * Unregister sysfs before flush sbi->s_sb_upd_work.
1295          * Since user may read /proc/fs/ext4/xx/mb_groups during umount, If
1296          * read metadata verify failed then will queue error work.
1297          * update_super_work will call start_this_handle may trigger
1298          * BUG_ON.
1299          */
1300         ext4_unregister_sysfs(sb);
1301
1302         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs unmount"))
1303                 ext4_msg(sb, KERN_INFO, "unmounting filesystem %pU.",
1304                          &sb->s_uuid);
1305
1306         ext4_unregister_li_request(sb);
1307         ext4_quotas_off(sb, EXT4_MAXQUOTAS);
1308
1309         flush_work(&sbi->s_sb_upd_work);
1310         destroy_workqueue(sbi->rsv_conversion_wq);
1311         ext4_release_orphan_info(sb);
1312
1313         if (sbi->s_journal) {
1314                 aborted = is_journal_aborted(sbi->s_journal);
1315                 err = jbd2_journal_destroy(sbi->s_journal);
1316                 sbi->s_journal = NULL;
1317                 if ((err < 0) && !aborted) {
1318                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1319                 }
1320         }
1321
1322         ext4_es_unregister_shrinker(sbi);
1323         timer_shutdown_sync(&sbi->s_err_report);
1324         ext4_release_system_zone(sb);
1325         ext4_mb_release(sb);
1326         ext4_ext_release(sb);
1327
1328         if (!sb_rdonly(sb) && !aborted) {
1329                 ext4_clear_feature_journal_needs_recovery(sb);
1330                 ext4_clear_feature_orphan_present(sb);
1331                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1332         }
1333         if (!sb_rdonly(sb))
1334                 ext4_commit_super(sb);
1335
1336         ext4_group_desc_free(sbi);
1337         ext4_flex_groups_free(sbi);
1338
1339         WARN_ON_ONCE(!(sbi->s_mount_state & EXT4_ERROR_FS) &&
1340                      percpu_counter_sum(&sbi->s_dirtyclusters_counter));
1341         ext4_percpu_param_destroy(sbi);
1342 #ifdef CONFIG_QUOTA
1343         for (int i = 0; i < EXT4_MAXQUOTAS; i++)
1344                 kfree(get_qf_name(sb, sbi, i));
1345 #endif
1346
1347         /* Debugging code just in case the in-memory inode orphan list
1348          * isn't empty.  The on-disk one can be non-empty if we've
1349          * detected an error and taken the fs readonly, but the
1350          * in-memory list had better be clean by this point. */
1351         if (!list_empty(&sbi->s_orphan))
1352                 dump_orphan_list(sb, sbi);
1353         ASSERT(list_empty(&sbi->s_orphan));
1354
1355         sync_blockdev(sb->s_bdev);
1356         invalidate_bdev(sb->s_bdev);
1357         if (sbi->s_journal_bdev_file) {
1358                 /*
1359                  * Invalidate the journal device's buffers.  We don't want them
1360                  * floating about in memory - the physical journal device may
1361                  * hotswapped, and it breaks the `ro-after' testing code.
1362                  */
1363                 sync_blockdev(file_bdev(sbi->s_journal_bdev_file));
1364                 invalidate_bdev(file_bdev(sbi->s_journal_bdev_file));
1365         }
1366
1367         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1368         sbi->s_ea_inode_cache = NULL;
1369
1370         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1371         sbi->s_ea_block_cache = NULL;
1372
1373         ext4_stop_mmpd(sbi);
1374
1375         brelse(sbi->s_sbh);
1376         sb->s_fs_info = NULL;
1377         /*
1378          * Now that we are completely done shutting down the
1379          * superblock, we need to actually destroy the kobject.
1380          */
1381         kobject_put(&sbi->s_kobj);
1382         wait_for_completion(&sbi->s_kobj_unregister);
1383         if (sbi->s_chksum_driver)
1384                 crypto_free_shash(sbi->s_chksum_driver);
1385         kfree(sbi->s_blockgroup_lock);
1386         fs_put_dax(sbi->s_daxdev, NULL);
1387         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1388 #if IS_ENABLED(CONFIG_UNICODE)
1389         utf8_unload(sb->s_encoding);
1390 #endif
1391         kfree(sbi);
1392 }
1393
1394 static struct kmem_cache *ext4_inode_cachep;
1395
1396 /*
1397  * Called inside transaction, so use GFP_NOFS
1398  */
1399 static struct inode *ext4_alloc_inode(struct super_block *sb)
1400 {
1401         struct ext4_inode_info *ei;
1402
1403         ei = alloc_inode_sb(sb, ext4_inode_cachep, GFP_NOFS);
1404         if (!ei)
1405                 return NULL;
1406
1407         inode_set_iversion(&ei->vfs_inode, 1);
1408         ei->i_flags = 0;
1409         spin_lock_init(&ei->i_raw_lock);
1410         ei->i_prealloc_node = RB_ROOT;
1411         atomic_set(&ei->i_prealloc_active, 0);
1412         rwlock_init(&ei->i_prealloc_lock);
1413         ext4_es_init_tree(&ei->i_es_tree);
1414         rwlock_init(&ei->i_es_lock);
1415         INIT_LIST_HEAD(&ei->i_es_list);
1416         ei->i_es_all_nr = 0;
1417         ei->i_es_shk_nr = 0;
1418         ei->i_es_shrink_lblk = 0;
1419         ei->i_reserved_data_blocks = 0;
1420         spin_lock_init(&(ei->i_block_reservation_lock));
1421         ext4_init_pending_tree(&ei->i_pending_tree);
1422 #ifdef CONFIG_QUOTA
1423         ei->i_reserved_quota = 0;
1424         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1425 #endif
1426         ei->jinode = NULL;
1427         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1428         spin_lock_init(&ei->i_completed_io_lock);
1429         ei->i_sync_tid = 0;
1430         ei->i_datasync_tid = 0;
1431         atomic_set(&ei->i_unwritten, 0);
1432         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1433         ext4_fc_init_inode(&ei->vfs_inode);
1434         mutex_init(&ei->i_fc_lock);
1435         return &ei->vfs_inode;
1436 }
1437
1438 static int ext4_drop_inode(struct inode *inode)
1439 {
1440         int drop = generic_drop_inode(inode);
1441
1442         if (!drop)
1443                 drop = fscrypt_drop_inode(inode);
1444
1445         trace_ext4_drop_inode(inode, drop);
1446         return drop;
1447 }
1448
1449 static void ext4_free_in_core_inode(struct inode *inode)
1450 {
1451         fscrypt_free_inode(inode);
1452         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1453                 pr_warn("%s: inode %ld still in fc list",
1454                         __func__, inode->i_ino);
1455         }
1456         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1457 }
1458
1459 static void ext4_destroy_inode(struct inode *inode)
1460 {
1461         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1462                 ext4_msg(inode->i_sb, KERN_ERR,
1463                          "Inode %lu (%p): orphan list check failed!",
1464                          inode->i_ino, EXT4_I(inode));
1465                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1466                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1467                                 true);
1468                 dump_stack();
1469         }
1470
1471         if (!(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ERROR_FS) &&
1472             WARN_ON_ONCE(EXT4_I(inode)->i_reserved_data_blocks))
1473                 ext4_msg(inode->i_sb, KERN_ERR,
1474                          "Inode %lu (%p): i_reserved_data_blocks (%u) not cleared!",
1475                          inode->i_ino, EXT4_I(inode),
1476                          EXT4_I(inode)->i_reserved_data_blocks);
1477 }
1478
1479 static void ext4_shutdown(struct super_block *sb)
1480 {
1481        ext4_force_shutdown(sb, EXT4_GOING_FLAGS_NOLOGFLUSH);
1482 }
1483
1484 static void init_once(void *foo)
1485 {
1486         struct ext4_inode_info *ei = foo;
1487
1488         INIT_LIST_HEAD(&ei->i_orphan);
1489         init_rwsem(&ei->xattr_sem);
1490         init_rwsem(&ei->i_data_sem);
1491         inode_init_once(&ei->vfs_inode);
1492         ext4_fc_init_inode(&ei->vfs_inode);
1493 }
1494
1495 static int __init init_inodecache(void)
1496 {
1497         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1498                                 sizeof(struct ext4_inode_info), 0,
1499                                 SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,
1500                                 offsetof(struct ext4_inode_info, i_data),
1501                                 sizeof_field(struct ext4_inode_info, i_data),
1502                                 init_once);
1503         if (ext4_inode_cachep == NULL)
1504                 return -ENOMEM;
1505         return 0;
1506 }
1507
1508 static void destroy_inodecache(void)
1509 {
1510         /*
1511          * Make sure all delayed rcu free inodes are flushed before we
1512          * destroy cache.
1513          */
1514         rcu_barrier();
1515         kmem_cache_destroy(ext4_inode_cachep);
1516 }
1517
1518 void ext4_clear_inode(struct inode *inode)
1519 {
1520         ext4_fc_del(inode);
1521         invalidate_inode_buffers(inode);
1522         clear_inode(inode);
1523         ext4_discard_preallocations(inode);
1524         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1525         dquot_drop(inode);
1526         if (EXT4_I(inode)->jinode) {
1527                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1528                                                EXT4_I(inode)->jinode);
1529                 jbd2_free_inode(EXT4_I(inode)->jinode);
1530                 EXT4_I(inode)->jinode = NULL;
1531         }
1532         fscrypt_put_encryption_info(inode);
1533         fsverity_cleanup_inode(inode);
1534 }
1535
1536 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1537                                         u64 ino, u32 generation)
1538 {
1539         struct inode *inode;
1540
1541         /*
1542          * Currently we don't know the generation for parent directory, so
1543          * a generation of 0 means "accept any"
1544          */
1545         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1546         if (IS_ERR(inode))
1547                 return ERR_CAST(inode);
1548         if (generation && inode->i_generation != generation) {
1549                 iput(inode);
1550                 return ERR_PTR(-ESTALE);
1551         }
1552
1553         return inode;
1554 }
1555
1556 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1557                                         int fh_len, int fh_type)
1558 {
1559         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1560                                     ext4_nfs_get_inode);
1561 }
1562
1563 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1564                                         int fh_len, int fh_type)
1565 {
1566         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1567                                     ext4_nfs_get_inode);
1568 }
1569
1570 static int ext4_nfs_commit_metadata(struct inode *inode)
1571 {
1572         struct writeback_control wbc = {
1573                 .sync_mode = WB_SYNC_ALL
1574         };
1575
1576         trace_ext4_nfs_commit_metadata(inode);
1577         return ext4_write_inode(inode, &wbc);
1578 }
1579
1580 #ifdef CONFIG_QUOTA
1581 static const char * const quotatypes[] = INITQFNAMES;
1582 #define QTYPE2NAME(t) (quotatypes[t])
1583
1584 static int ext4_write_dquot(struct dquot *dquot);
1585 static int ext4_acquire_dquot(struct dquot *dquot);
1586 static int ext4_release_dquot(struct dquot *dquot);
1587 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1588 static int ext4_write_info(struct super_block *sb, int type);
1589 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1590                          const struct path *path);
1591 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1592                                size_t len, loff_t off);
1593 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1594                                 const char *data, size_t len, loff_t off);
1595 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1596                              unsigned int flags);
1597
1598 static struct dquot __rcu **ext4_get_dquots(struct inode *inode)
1599 {
1600         return EXT4_I(inode)->i_dquot;
1601 }
1602
1603 static const struct dquot_operations ext4_quota_operations = {
1604         .get_reserved_space     = ext4_get_reserved_space,
1605         .write_dquot            = ext4_write_dquot,
1606         .acquire_dquot          = ext4_acquire_dquot,
1607         .release_dquot          = ext4_release_dquot,
1608         .mark_dirty             = ext4_mark_dquot_dirty,
1609         .write_info             = ext4_write_info,
1610         .alloc_dquot            = dquot_alloc,
1611         .destroy_dquot          = dquot_destroy,
1612         .get_projid             = ext4_get_projid,
1613         .get_inode_usage        = ext4_get_inode_usage,
1614         .get_next_id            = dquot_get_next_id,
1615 };
1616
1617 static const struct quotactl_ops ext4_qctl_operations = {
1618         .quota_on       = ext4_quota_on,
1619         .quota_off      = ext4_quota_off,
1620         .quota_sync     = dquot_quota_sync,
1621         .get_state      = dquot_get_state,
1622         .set_info       = dquot_set_dqinfo,
1623         .get_dqblk      = dquot_get_dqblk,
1624         .set_dqblk      = dquot_set_dqblk,
1625         .get_nextdqblk  = dquot_get_next_dqblk,
1626 };
1627 #endif
1628
1629 static const struct super_operations ext4_sops = {
1630         .alloc_inode    = ext4_alloc_inode,
1631         .free_inode     = ext4_free_in_core_inode,
1632         .destroy_inode  = ext4_destroy_inode,
1633         .write_inode    = ext4_write_inode,
1634         .dirty_inode    = ext4_dirty_inode,
1635         .drop_inode     = ext4_drop_inode,
1636         .evict_inode    = ext4_evict_inode,
1637         .put_super      = ext4_put_super,
1638         .sync_fs        = ext4_sync_fs,
1639         .freeze_fs      = ext4_freeze,
1640         .unfreeze_fs    = ext4_unfreeze,
1641         .statfs         = ext4_statfs,
1642         .show_options   = ext4_show_options,
1643         .shutdown       = ext4_shutdown,
1644 #ifdef CONFIG_QUOTA
1645         .quota_read     = ext4_quota_read,
1646         .quota_write    = ext4_quota_write,
1647         .get_dquots     = ext4_get_dquots,
1648 #endif
1649 };
1650
1651 static const struct export_operations ext4_export_ops = {
1652         .encode_fh = generic_encode_ino32_fh,
1653         .fh_to_dentry = ext4_fh_to_dentry,
1654         .fh_to_parent = ext4_fh_to_parent,
1655         .get_parent = ext4_get_parent,
1656         .commit_metadata = ext4_nfs_commit_metadata,
1657 };
1658
1659 enum {
1660         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1661         Opt_resgid, Opt_resuid, Opt_sb,
1662         Opt_nouid32, Opt_debug, Opt_removed,
1663         Opt_user_xattr, Opt_acl,
1664         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1665         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1666         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1667         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1668         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1669         Opt_inlinecrypt,
1670         Opt_usrjquota, Opt_grpjquota, Opt_quota,
1671         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1672         Opt_usrquota, Opt_grpquota, Opt_prjquota,
1673         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1674         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1675         Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
1676         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1677         Opt_inode_readahead_blks, Opt_journal_ioprio,
1678         Opt_dioread_nolock, Opt_dioread_lock,
1679         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1680         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1681         Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1682         Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
1683 #ifdef CONFIG_EXT4_DEBUG
1684         Opt_fc_debug_max_replay, Opt_fc_debug_force
1685 #endif
1686 };
1687
1688 static const struct constant_table ext4_param_errors[] = {
1689         {"continue",    EXT4_MOUNT_ERRORS_CONT},
1690         {"panic",       EXT4_MOUNT_ERRORS_PANIC},
1691         {"remount-ro",  EXT4_MOUNT_ERRORS_RO},
1692         {}
1693 };
1694
1695 static const struct constant_table ext4_param_data[] = {
1696         {"journal",     EXT4_MOUNT_JOURNAL_DATA},
1697         {"ordered",     EXT4_MOUNT_ORDERED_DATA},
1698         {"writeback",   EXT4_MOUNT_WRITEBACK_DATA},
1699         {}
1700 };
1701
1702 static const struct constant_table ext4_param_data_err[] = {
1703         {"abort",       Opt_data_err_abort},
1704         {"ignore",      Opt_data_err_ignore},
1705         {}
1706 };
1707
1708 static const struct constant_table ext4_param_jqfmt[] = {
1709         {"vfsold",      QFMT_VFS_OLD},
1710         {"vfsv0",       QFMT_VFS_V0},
1711         {"vfsv1",       QFMT_VFS_V1},
1712         {}
1713 };
1714
1715 static const struct constant_table ext4_param_dax[] = {
1716         {"always",      Opt_dax_always},
1717         {"inode",       Opt_dax_inode},
1718         {"never",       Opt_dax_never},
1719         {}
1720 };
1721
1722 /*
1723  * Mount option specification
1724  * We don't use fsparam_flag_no because of the way we set the
1725  * options and the way we show them in _ext4_show_options(). To
1726  * keep the changes to a minimum, let's keep the negative options
1727  * separate for now.
1728  */
1729 static const struct fs_parameter_spec ext4_param_specs[] = {
1730         fsparam_flag    ("bsddf",               Opt_bsd_df),
1731         fsparam_flag    ("minixdf",             Opt_minix_df),
1732         fsparam_flag    ("grpid",               Opt_grpid),
1733         fsparam_flag    ("bsdgroups",           Opt_grpid),
1734         fsparam_flag    ("nogrpid",             Opt_nogrpid),
1735         fsparam_flag    ("sysvgroups",          Opt_nogrpid),
1736         fsparam_gid     ("resgid",              Opt_resgid),
1737         fsparam_uid     ("resuid",              Opt_resuid),
1738         fsparam_u32     ("sb",                  Opt_sb),
1739         fsparam_enum    ("errors",              Opt_errors, ext4_param_errors),
1740         fsparam_flag    ("nouid32",             Opt_nouid32),
1741         fsparam_flag    ("debug",               Opt_debug),
1742         fsparam_flag    ("oldalloc",            Opt_removed),
1743         fsparam_flag    ("orlov",               Opt_removed),
1744         fsparam_flag    ("user_xattr",          Opt_user_xattr),
1745         fsparam_flag    ("acl",                 Opt_acl),
1746         fsparam_flag    ("norecovery",          Opt_noload),
1747         fsparam_flag    ("noload",              Opt_noload),
1748         fsparam_flag    ("bh",                  Opt_removed),
1749         fsparam_flag    ("nobh",                Opt_removed),
1750         fsparam_u32     ("commit",              Opt_commit),
1751         fsparam_u32     ("min_batch_time",      Opt_min_batch_time),
1752         fsparam_u32     ("max_batch_time",      Opt_max_batch_time),
1753         fsparam_u32     ("journal_dev",         Opt_journal_dev),
1754         fsparam_bdev    ("journal_path",        Opt_journal_path),
1755         fsparam_flag    ("journal_checksum",    Opt_journal_checksum),
1756         fsparam_flag    ("nojournal_checksum",  Opt_nojournal_checksum),
1757         fsparam_flag    ("journal_async_commit",Opt_journal_async_commit),
1758         fsparam_flag    ("abort",               Opt_abort),
1759         fsparam_enum    ("data",                Opt_data, ext4_param_data),
1760         fsparam_enum    ("data_err",            Opt_data_err,
1761                                                 ext4_param_data_err),
1762         fsparam_string_empty
1763                         ("usrjquota",           Opt_usrjquota),
1764         fsparam_string_empty
1765                         ("grpjquota",           Opt_grpjquota),
1766         fsparam_enum    ("jqfmt",               Opt_jqfmt, ext4_param_jqfmt),
1767         fsparam_flag    ("grpquota",            Opt_grpquota),
1768         fsparam_flag    ("quota",               Opt_quota),
1769         fsparam_flag    ("noquota",             Opt_noquota),
1770         fsparam_flag    ("usrquota",            Opt_usrquota),
1771         fsparam_flag    ("prjquota",            Opt_prjquota),
1772         fsparam_flag    ("barrier",             Opt_barrier),
1773         fsparam_u32     ("barrier",             Opt_barrier),
1774         fsparam_flag    ("nobarrier",           Opt_nobarrier),
1775         fsparam_flag    ("i_version",           Opt_removed),
1776         fsparam_flag    ("dax",                 Opt_dax),
1777         fsparam_enum    ("dax",                 Opt_dax_type, ext4_param_dax),
1778         fsparam_u32     ("stripe",              Opt_stripe),
1779         fsparam_flag    ("delalloc",            Opt_delalloc),
1780         fsparam_flag    ("nodelalloc",          Opt_nodelalloc),
1781         fsparam_flag    ("warn_on_error",       Opt_warn_on_error),
1782         fsparam_flag    ("nowarn_on_error",     Opt_nowarn_on_error),
1783         fsparam_u32     ("debug_want_extra_isize",
1784                                                 Opt_debug_want_extra_isize),
1785         fsparam_flag    ("mblk_io_submit",      Opt_removed),
1786         fsparam_flag    ("nomblk_io_submit",    Opt_removed),
1787         fsparam_flag    ("block_validity",      Opt_block_validity),
1788         fsparam_flag    ("noblock_validity",    Opt_noblock_validity),
1789         fsparam_u32     ("inode_readahead_blks",
1790                                                 Opt_inode_readahead_blks),
1791         fsparam_u32     ("journal_ioprio",      Opt_journal_ioprio),
1792         fsparam_u32     ("auto_da_alloc",       Opt_auto_da_alloc),
1793         fsparam_flag    ("auto_da_alloc",       Opt_auto_da_alloc),
1794         fsparam_flag    ("noauto_da_alloc",     Opt_noauto_da_alloc),
1795         fsparam_flag    ("dioread_nolock",      Opt_dioread_nolock),
1796         fsparam_flag    ("nodioread_nolock",    Opt_dioread_lock),
1797         fsparam_flag    ("dioread_lock",        Opt_dioread_lock),
1798         fsparam_flag    ("discard",             Opt_discard),
1799         fsparam_flag    ("nodiscard",           Opt_nodiscard),
1800         fsparam_u32     ("init_itable",         Opt_init_itable),
1801         fsparam_flag    ("init_itable",         Opt_init_itable),
1802         fsparam_flag    ("noinit_itable",       Opt_noinit_itable),
1803 #ifdef CONFIG_EXT4_DEBUG
1804         fsparam_flag    ("fc_debug_force",      Opt_fc_debug_force),
1805         fsparam_u32     ("fc_debug_max_replay", Opt_fc_debug_max_replay),
1806 #endif
1807         fsparam_u32     ("max_dir_size_kb",     Opt_max_dir_size_kb),
1808         fsparam_flag    ("test_dummy_encryption",
1809                                                 Opt_test_dummy_encryption),
1810         fsparam_string  ("test_dummy_encryption",
1811                                                 Opt_test_dummy_encryption),
1812         fsparam_flag    ("inlinecrypt",         Opt_inlinecrypt),
1813         fsparam_flag    ("nombcache",           Opt_nombcache),
1814         fsparam_flag    ("no_mbcache",          Opt_nombcache), /* for backward compatibility */
1815         fsparam_flag    ("prefetch_block_bitmaps",
1816                                                 Opt_removed),
1817         fsparam_flag    ("no_prefetch_block_bitmaps",
1818                                                 Opt_no_prefetch_block_bitmaps),
1819         fsparam_s32     ("mb_optimize_scan",    Opt_mb_optimize_scan),
1820         fsparam_string  ("check",               Opt_removed),   /* mount option from ext2/3 */
1821         fsparam_flag    ("nocheck",             Opt_removed),   /* mount option from ext2/3 */
1822         fsparam_flag    ("reservation",         Opt_removed),   /* mount option from ext2/3 */
1823         fsparam_flag    ("noreservation",       Opt_removed),   /* mount option from ext2/3 */
1824         fsparam_u32     ("journal",             Opt_removed),   /* mount option from ext2/3 */
1825         {}
1826 };
1827
1828 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1829
1830 #define MOPT_SET        0x0001
1831 #define MOPT_CLEAR      0x0002
1832 #define MOPT_NOSUPPORT  0x0004
1833 #define MOPT_EXPLICIT   0x0008
1834 #ifdef CONFIG_QUOTA
1835 #define MOPT_Q          0
1836 #define MOPT_QFMT       0x0010
1837 #else
1838 #define MOPT_Q          MOPT_NOSUPPORT
1839 #define MOPT_QFMT       MOPT_NOSUPPORT
1840 #endif
1841 #define MOPT_NO_EXT2    0x0020
1842 #define MOPT_NO_EXT3    0x0040
1843 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1844 #define MOPT_SKIP       0x0080
1845 #define MOPT_2          0x0100
1846
1847 static const struct mount_opts {
1848         int     token;
1849         int     mount_opt;
1850         int     flags;
1851 } ext4_mount_opts[] = {
1852         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1853         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1854         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1855         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1856         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1857         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1858         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1859          MOPT_EXT4_ONLY | MOPT_SET},
1860         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1861          MOPT_EXT4_ONLY | MOPT_CLEAR},
1862         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1863         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1864         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1865          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1866         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1867          MOPT_EXT4_ONLY | MOPT_CLEAR},
1868         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1869         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1870         {Opt_commit, 0, MOPT_NO_EXT2},
1871         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1872          MOPT_EXT4_ONLY | MOPT_CLEAR},
1873         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1874          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1875         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1876                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1877          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1878         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1879         {Opt_data_err, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_NO_EXT2},
1880         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1881         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1882         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1883         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1884         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1885         {Opt_dax_type, 0, MOPT_EXT4_ONLY},
1886         {Opt_journal_dev, 0, MOPT_NO_EXT2},
1887         {Opt_journal_path, 0, MOPT_NO_EXT2},
1888         {Opt_journal_ioprio, 0, MOPT_NO_EXT2},
1889         {Opt_data, 0, MOPT_NO_EXT2},
1890         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1891 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1892         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1893 #else
1894         {Opt_acl, 0, MOPT_NOSUPPORT},
1895 #endif
1896         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1897         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1898         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1899         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1900                                                         MOPT_SET | MOPT_Q},
1901         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1902                                                         MOPT_SET | MOPT_Q},
1903         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1904                                                         MOPT_SET | MOPT_Q},
1905         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1906                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1907                                                         MOPT_CLEAR | MOPT_Q},
1908         {Opt_usrjquota, 0, MOPT_Q},
1909         {Opt_grpjquota, 0, MOPT_Q},
1910         {Opt_jqfmt, 0, MOPT_QFMT},
1911         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1912         {Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
1913          MOPT_SET},
1914 #ifdef CONFIG_EXT4_DEBUG
1915         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1916          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1917 #endif
1918         {Opt_abort, EXT4_MOUNT2_ABORT, MOPT_SET | MOPT_2},
1919         {Opt_err, 0, 0}
1920 };
1921
1922 #if IS_ENABLED(CONFIG_UNICODE)
1923 static const struct ext4_sb_encodings {
1924         __u16 magic;
1925         char *name;
1926         unsigned int version;
1927 } ext4_sb_encoding_map[] = {
1928         {EXT4_ENC_UTF8_12_1, "utf8", UNICODE_AGE(12, 1, 0)},
1929 };
1930
1931 static const struct ext4_sb_encodings *
1932 ext4_sb_read_encoding(const struct ext4_super_block *es)
1933 {
1934         __u16 magic = le16_to_cpu(es->s_encoding);
1935         int i;
1936
1937         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1938                 if (magic == ext4_sb_encoding_map[i].magic)
1939                         return &ext4_sb_encoding_map[i];
1940
1941         return NULL;
1942 }
1943 #endif
1944
1945 #define EXT4_SPEC_JQUOTA                        (1 <<  0)
1946 #define EXT4_SPEC_JQFMT                         (1 <<  1)
1947 #define EXT4_SPEC_DATAJ                         (1 <<  2)
1948 #define EXT4_SPEC_SB_BLOCK                      (1 <<  3)
1949 #define EXT4_SPEC_JOURNAL_DEV                   (1 <<  4)
1950 #define EXT4_SPEC_JOURNAL_IOPRIO                (1 <<  5)
1951 #define EXT4_SPEC_s_want_extra_isize            (1 <<  7)
1952 #define EXT4_SPEC_s_max_batch_time              (1 <<  8)
1953 #define EXT4_SPEC_s_min_batch_time              (1 <<  9)
1954 #define EXT4_SPEC_s_inode_readahead_blks        (1 << 10)
1955 #define EXT4_SPEC_s_li_wait_mult                (1 << 11)
1956 #define EXT4_SPEC_s_max_dir_size_kb             (1 << 12)
1957 #define EXT4_SPEC_s_stripe                      (1 << 13)
1958 #define EXT4_SPEC_s_resuid                      (1 << 14)
1959 #define EXT4_SPEC_s_resgid                      (1 << 15)
1960 #define EXT4_SPEC_s_commit_interval             (1 << 16)
1961 #define EXT4_SPEC_s_fc_debug_max_replay         (1 << 17)
1962 #define EXT4_SPEC_s_sb_block                    (1 << 18)
1963 #define EXT4_SPEC_mb_optimize_scan              (1 << 19)
1964
1965 struct ext4_fs_context {
1966         char            *s_qf_names[EXT4_MAXQUOTAS];
1967         struct fscrypt_dummy_policy dummy_enc_policy;
1968         int             s_jquota_fmt;   /* Format of quota to use */
1969 #ifdef CONFIG_EXT4_DEBUG
1970         int s_fc_debug_max_replay;
1971 #endif
1972         unsigned short  qname_spec;
1973         unsigned long   vals_s_flags;   /* Bits to set in s_flags */
1974         unsigned long   mask_s_flags;   /* Bits changed in s_flags */
1975         unsigned long   journal_devnum;
1976         unsigned long   s_commit_interval;
1977         unsigned long   s_stripe;
1978         unsigned int    s_inode_readahead_blks;
1979         unsigned int    s_want_extra_isize;
1980         unsigned int    s_li_wait_mult;
1981         unsigned int    s_max_dir_size_kb;
1982         unsigned int    journal_ioprio;
1983         unsigned int    vals_s_mount_opt;
1984         unsigned int    mask_s_mount_opt;
1985         unsigned int    vals_s_mount_opt2;
1986         unsigned int    mask_s_mount_opt2;
1987         unsigned int    opt_flags;      /* MOPT flags */
1988         unsigned int    spec;
1989         u32             s_max_batch_time;
1990         u32             s_min_batch_time;
1991         kuid_t          s_resuid;
1992         kgid_t          s_resgid;
1993         ext4_fsblk_t    s_sb_block;
1994 };
1995
1996 static void ext4_fc_free(struct fs_context *fc)
1997 {
1998         struct ext4_fs_context *ctx = fc->fs_private;
1999         int i;
2000
2001         if (!ctx)
2002                 return;
2003
2004         for (i = 0; i < EXT4_MAXQUOTAS; i++)
2005                 kfree(ctx->s_qf_names[i]);
2006
2007         fscrypt_free_dummy_policy(&ctx->dummy_enc_policy);
2008         kfree(ctx);
2009 }
2010
2011 int ext4_init_fs_context(struct fs_context *fc)
2012 {
2013         struct ext4_fs_context *ctx;
2014
2015         ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2016         if (!ctx)
2017                 return -ENOMEM;
2018
2019         fc->fs_private = ctx;
2020         fc->ops = &ext4_context_ops;
2021
2022         return 0;
2023 }
2024
2025 #ifdef CONFIG_QUOTA
2026 /*
2027  * Note the name of the specified quota file.
2028  */
2029 static int note_qf_name(struct fs_context *fc, int qtype,
2030                        struct fs_parameter *param)
2031 {
2032         struct ext4_fs_context *ctx = fc->fs_private;
2033         char *qname;
2034
2035         if (param->size < 1) {
2036                 ext4_msg(NULL, KERN_ERR, "Missing quota name");
2037                 return -EINVAL;
2038         }
2039         if (strchr(param->string, '/')) {
2040                 ext4_msg(NULL, KERN_ERR,
2041                          "quotafile must be on filesystem root");
2042                 return -EINVAL;
2043         }
2044         if (ctx->s_qf_names[qtype]) {
2045                 if (strcmp(ctx->s_qf_names[qtype], param->string) != 0) {
2046                         ext4_msg(NULL, KERN_ERR,
2047                                  "%s quota file already specified",
2048                                  QTYPE2NAME(qtype));
2049                         return -EINVAL;
2050                 }
2051                 return 0;
2052         }
2053
2054         qname = kmemdup_nul(param->string, param->size, GFP_KERNEL);
2055         if (!qname) {
2056                 ext4_msg(NULL, KERN_ERR,
2057                          "Not enough memory for storing quotafile name");
2058                 return -ENOMEM;
2059         }
2060         ctx->s_qf_names[qtype] = qname;
2061         ctx->qname_spec |= 1 << qtype;
2062         ctx->spec |= EXT4_SPEC_JQUOTA;
2063         return 0;
2064 }
2065
2066 /*
2067  * Clear the name of the specified quota file.
2068  */
2069 static int unnote_qf_name(struct fs_context *fc, int qtype)
2070 {
2071         struct ext4_fs_context *ctx = fc->fs_private;
2072
2073         kfree(ctx->s_qf_names[qtype]);
2074
2075         ctx->s_qf_names[qtype] = NULL;
2076         ctx->qname_spec |= 1 << qtype;
2077         ctx->spec |= EXT4_SPEC_JQUOTA;
2078         return 0;
2079 }
2080 #endif
2081
2082 static int ext4_parse_test_dummy_encryption(const struct fs_parameter *param,
2083                                             struct ext4_fs_context *ctx)
2084 {
2085         int err;
2086
2087         if (!IS_ENABLED(CONFIG_FS_ENCRYPTION)) {
2088                 ext4_msg(NULL, KERN_WARNING,
2089                          "test_dummy_encryption option not supported");
2090                 return -EINVAL;
2091         }
2092         err = fscrypt_parse_test_dummy_encryption(param,
2093                                                   &ctx->dummy_enc_policy);
2094         if (err == -EINVAL) {
2095                 ext4_msg(NULL, KERN_WARNING,
2096                          "Value of option \"%s\" is unrecognized", param->key);
2097         } else if (err == -EEXIST) {
2098                 ext4_msg(NULL, KERN_WARNING,
2099                          "Conflicting test_dummy_encryption options");
2100                 return -EINVAL;
2101         }
2102         return err;
2103 }
2104
2105 #define EXT4_SET_CTX(name)                                              \
2106 static inline __maybe_unused                                            \
2107 void ctx_set_##name(struct ext4_fs_context *ctx, unsigned long flag)    \
2108 {                                                                       \
2109         ctx->mask_s_##name |= flag;                                     \
2110         ctx->vals_s_##name |= flag;                                     \
2111 }
2112
2113 #define EXT4_CLEAR_CTX(name)                                            \
2114 static inline __maybe_unused                                            \
2115 void ctx_clear_##name(struct ext4_fs_context *ctx, unsigned long flag)  \
2116 {                                                                       \
2117         ctx->mask_s_##name |= flag;                                     \
2118         ctx->vals_s_##name &= ~flag;                                    \
2119 }
2120
2121 #define EXT4_TEST_CTX(name)                                             \
2122 static inline unsigned long                                             \
2123 ctx_test_##name(struct ext4_fs_context *ctx, unsigned long flag)        \
2124 {                                                                       \
2125         return (ctx->vals_s_##name & flag);                             \
2126 }
2127
2128 EXT4_SET_CTX(flags); /* set only */
2129 EXT4_SET_CTX(mount_opt);
2130 EXT4_CLEAR_CTX(mount_opt);
2131 EXT4_TEST_CTX(mount_opt);
2132 EXT4_SET_CTX(mount_opt2);
2133 EXT4_CLEAR_CTX(mount_opt2);
2134 EXT4_TEST_CTX(mount_opt2);
2135
2136 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
2137 {
2138         struct ext4_fs_context *ctx = fc->fs_private;
2139         struct fs_parse_result result;
2140         const struct mount_opts *m;
2141         int is_remount;
2142         int token;
2143
2144         token = fs_parse(fc, ext4_param_specs, param, &result);
2145         if (token < 0)
2146                 return token;
2147         is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2148
2149         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2150                 if (token == m->token)
2151                         break;
2152
2153         ctx->opt_flags |= m->flags;
2154
2155         if (m->flags & MOPT_EXPLICIT) {
2156                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2157                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_EXPLICIT_DELALLOC);
2158                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2159                         ctx_set_mount_opt2(ctx,
2160                                        EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM);
2161                 } else
2162                         return -EINVAL;
2163         }
2164
2165         if (m->flags & MOPT_NOSUPPORT) {
2166                 ext4_msg(NULL, KERN_ERR, "%s option not supported",
2167                          param->key);
2168                 return 0;
2169         }
2170
2171         switch (token) {
2172 #ifdef CONFIG_QUOTA
2173         case Opt_usrjquota:
2174                 if (!*param->string)
2175                         return unnote_qf_name(fc, USRQUOTA);
2176                 else
2177                         return note_qf_name(fc, USRQUOTA, param);
2178         case Opt_grpjquota:
2179                 if (!*param->string)
2180                         return unnote_qf_name(fc, GRPQUOTA);
2181                 else
2182                         return note_qf_name(fc, GRPQUOTA, param);
2183 #endif
2184         case Opt_sb:
2185                 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2186                         ext4_msg(NULL, KERN_WARNING,
2187                                  "Ignoring %s option on remount", param->key);
2188                 } else {
2189                         ctx->s_sb_block = result.uint_32;
2190                         ctx->spec |= EXT4_SPEC_s_sb_block;
2191                 }
2192                 return 0;
2193         case Opt_removed:
2194                 ext4_msg(NULL, KERN_WARNING, "Ignoring removed %s option",
2195                          param->key);
2196                 return 0;
2197         case Opt_inlinecrypt:
2198 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2199                 ctx_set_flags(ctx, SB_INLINECRYPT);
2200 #else
2201                 ext4_msg(NULL, KERN_ERR, "inline encryption not supported");
2202 #endif
2203                 return 0;
2204         case Opt_errors:
2205                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_ERRORS_MASK);
2206                 ctx_set_mount_opt(ctx, result.uint_32);
2207                 return 0;
2208 #ifdef CONFIG_QUOTA
2209         case Opt_jqfmt:
2210                 ctx->s_jquota_fmt = result.uint_32;
2211                 ctx->spec |= EXT4_SPEC_JQFMT;
2212                 return 0;
2213 #endif
2214         case Opt_data:
2215                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2216                 ctx_set_mount_opt(ctx, result.uint_32);
2217                 ctx->spec |= EXT4_SPEC_DATAJ;
2218                 return 0;
2219         case Opt_commit:
2220                 if (result.uint_32 == 0)
2221                         result.uint_32 = JBD2_DEFAULT_MAX_COMMIT_AGE;
2222                 else if (result.uint_32 > INT_MAX / HZ) {
2223                         ext4_msg(NULL, KERN_ERR,
2224                                  "Invalid commit interval %d, "
2225                                  "must be smaller than %d",
2226                                  result.uint_32, INT_MAX / HZ);
2227                         return -EINVAL;
2228                 }
2229                 ctx->s_commit_interval = HZ * result.uint_32;
2230                 ctx->spec |= EXT4_SPEC_s_commit_interval;
2231                 return 0;
2232         case Opt_debug_want_extra_isize:
2233                 if ((result.uint_32 & 1) || (result.uint_32 < 4)) {
2234                         ext4_msg(NULL, KERN_ERR,
2235                                  "Invalid want_extra_isize %d", result.uint_32);
2236                         return -EINVAL;
2237                 }
2238                 ctx->s_want_extra_isize = result.uint_32;
2239                 ctx->spec |= EXT4_SPEC_s_want_extra_isize;
2240                 return 0;
2241         case Opt_max_batch_time:
2242                 ctx->s_max_batch_time = result.uint_32;
2243                 ctx->spec |= EXT4_SPEC_s_max_batch_time;
2244                 return 0;
2245         case Opt_min_batch_time:
2246                 ctx->s_min_batch_time = result.uint_32;
2247                 ctx->spec |= EXT4_SPEC_s_min_batch_time;
2248                 return 0;
2249         case Opt_inode_readahead_blks:
2250                 if (result.uint_32 &&
2251                     (result.uint_32 > (1 << 30) ||
2252                      !is_power_of_2(result.uint_32))) {
2253                         ext4_msg(NULL, KERN_ERR,
2254                                  "EXT4-fs: inode_readahead_blks must be "
2255                                  "0 or a power of 2 smaller than 2^31");
2256                         return -EINVAL;
2257                 }
2258                 ctx->s_inode_readahead_blks = result.uint_32;
2259                 ctx->spec |= EXT4_SPEC_s_inode_readahead_blks;
2260                 return 0;
2261         case Opt_init_itable:
2262                 ctx_set_mount_opt(ctx, EXT4_MOUNT_INIT_INODE_TABLE);
2263                 ctx->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
2264                 if (param->type == fs_value_is_string)
2265                         ctx->s_li_wait_mult = result.uint_32;
2266                 ctx->spec |= EXT4_SPEC_s_li_wait_mult;
2267                 return 0;
2268         case Opt_max_dir_size_kb:
2269                 ctx->s_max_dir_size_kb = result.uint_32;
2270                 ctx->spec |= EXT4_SPEC_s_max_dir_size_kb;
2271                 return 0;
2272 #ifdef CONFIG_EXT4_DEBUG
2273         case Opt_fc_debug_max_replay:
2274                 ctx->s_fc_debug_max_replay = result.uint_32;
2275                 ctx->spec |= EXT4_SPEC_s_fc_debug_max_replay;
2276                 return 0;
2277 #endif
2278         case Opt_stripe:
2279                 ctx->s_stripe = result.uint_32;
2280                 ctx->spec |= EXT4_SPEC_s_stripe;
2281                 return 0;
2282         case Opt_resuid:
2283                 ctx->s_resuid = result.uid;
2284                 ctx->spec |= EXT4_SPEC_s_resuid;
2285                 return 0;
2286         case Opt_resgid:
2287                 ctx->s_resgid = result.gid;
2288                 ctx->spec |= EXT4_SPEC_s_resgid;
2289                 return 0;
2290         case Opt_journal_dev:
2291                 if (is_remount) {
2292                         ext4_msg(NULL, KERN_ERR,
2293                                  "Cannot specify journal on remount");
2294                         return -EINVAL;
2295                 }
2296                 ctx->journal_devnum = result.uint_32;
2297                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2298                 return 0;
2299         case Opt_journal_path:
2300         {
2301                 struct inode *journal_inode;
2302                 struct path path;
2303                 int error;
2304
2305                 if (is_remount) {
2306                         ext4_msg(NULL, KERN_ERR,
2307                                  "Cannot specify journal on remount");
2308                         return -EINVAL;
2309                 }
2310
2311                 error = fs_lookup_param(fc, param, 1, LOOKUP_FOLLOW, &path);
2312                 if (error) {
2313                         ext4_msg(NULL, KERN_ERR, "error: could not find "
2314                                  "journal device path");
2315                         return -EINVAL;
2316                 }
2317
2318                 journal_inode = d_inode(path.dentry);
2319                 ctx->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2320                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2321                 path_put(&path);
2322                 return 0;
2323         }
2324         case Opt_journal_ioprio:
2325                 if (result.uint_32 > 7) {
2326                         ext4_msg(NULL, KERN_ERR, "Invalid journal IO priority"
2327                                  " (must be 0-7)");
2328                         return -EINVAL;
2329                 }
2330                 ctx->journal_ioprio =
2331                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, result.uint_32);
2332                 ctx->spec |= EXT4_SPEC_JOURNAL_IOPRIO;
2333                 return 0;
2334         case Opt_test_dummy_encryption:
2335                 return ext4_parse_test_dummy_encryption(param, ctx);
2336         case Opt_dax:
2337         case Opt_dax_type:
2338 #ifdef CONFIG_FS_DAX
2339         {
2340                 int type = (token == Opt_dax) ?
2341                            Opt_dax : result.uint_32;
2342
2343                 switch (type) {
2344                 case Opt_dax:
2345                 case Opt_dax_always:
2346                         ctx_set_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2347                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2348                         break;
2349                 case Opt_dax_never:
2350                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2351                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2352                         break;
2353                 case Opt_dax_inode:
2354                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2355                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2356                         /* Strictly for printing options */
2357                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE);
2358                         break;
2359                 }
2360                 return 0;
2361         }
2362 #else
2363                 ext4_msg(NULL, KERN_INFO, "dax option not supported");
2364                 return -EINVAL;
2365 #endif
2366         case Opt_data_err:
2367                 if (result.uint_32 == Opt_data_err_abort)
2368                         ctx_set_mount_opt(ctx, m->mount_opt);
2369                 else if (result.uint_32 == Opt_data_err_ignore)
2370                         ctx_clear_mount_opt(ctx, m->mount_opt);
2371                 return 0;
2372         case Opt_mb_optimize_scan:
2373                 if (result.int_32 == 1) {
2374                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2375                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2376                 } else if (result.int_32 == 0) {
2377                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2378                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2379                 } else {
2380                         ext4_msg(NULL, KERN_WARNING,
2381                                  "mb_optimize_scan should be set to 0 or 1.");
2382                         return -EINVAL;
2383                 }
2384                 return 0;
2385         }
2386
2387         /*
2388          * At this point we should only be getting options requiring MOPT_SET,
2389          * or MOPT_CLEAR. Anything else is a bug
2390          */
2391         if (m->token == Opt_err) {
2392                 ext4_msg(NULL, KERN_WARNING, "buggy handling of option %s",
2393                          param->key);
2394                 WARN_ON(1);
2395                 return -EINVAL;
2396         }
2397
2398         else {
2399                 unsigned int set = 0;
2400
2401                 if ((param->type == fs_value_is_flag) ||
2402                     result.uint_32 > 0)
2403                         set = 1;
2404
2405                 if (m->flags & MOPT_CLEAR)
2406                         set = !set;
2407                 else if (unlikely(!(m->flags & MOPT_SET))) {
2408                         ext4_msg(NULL, KERN_WARNING,
2409                                  "buggy handling of option %s",
2410                                  param->key);
2411                         WARN_ON(1);
2412                         return -EINVAL;
2413                 }
2414                 if (m->flags & MOPT_2) {
2415                         if (set != 0)
2416                                 ctx_set_mount_opt2(ctx, m->mount_opt);
2417                         else
2418                                 ctx_clear_mount_opt2(ctx, m->mount_opt);
2419                 } else {
2420                         if (set != 0)
2421                                 ctx_set_mount_opt(ctx, m->mount_opt);
2422                         else
2423                                 ctx_clear_mount_opt(ctx, m->mount_opt);
2424                 }
2425         }
2426
2427         return 0;
2428 }
2429
2430 static int parse_options(struct fs_context *fc, char *options)
2431 {
2432         struct fs_parameter param;
2433         int ret;
2434         char *key;
2435
2436         if (!options)
2437                 return 0;
2438
2439         while ((key = strsep(&options, ",")) != NULL) {
2440                 if (*key) {
2441                         size_t v_len = 0;
2442                         char *value = strchr(key, '=');
2443
2444                         param.type = fs_value_is_flag;
2445                         param.string = NULL;
2446
2447                         if (value) {
2448                                 if (value == key)
2449                                         continue;
2450
2451                                 *value++ = 0;
2452                                 v_len = strlen(value);
2453                                 param.string = kmemdup_nul(value, v_len,
2454                                                            GFP_KERNEL);
2455                                 if (!param.string)
2456                                         return -ENOMEM;
2457                                 param.type = fs_value_is_string;
2458                         }
2459
2460                         param.key = key;
2461                         param.size = v_len;
2462
2463                         ret = ext4_parse_param(fc, &param);
2464                         kfree(param.string);
2465                         if (ret < 0)
2466                                 return ret;
2467                 }
2468         }
2469
2470         ret = ext4_validate_options(fc);
2471         if (ret < 0)
2472                 return ret;
2473
2474         return 0;
2475 }
2476
2477 static int parse_apply_sb_mount_options(struct super_block *sb,
2478                                         struct ext4_fs_context *m_ctx)
2479 {
2480         struct ext4_sb_info *sbi = EXT4_SB(sb);
2481         char *s_mount_opts = NULL;
2482         struct ext4_fs_context *s_ctx = NULL;
2483         struct fs_context *fc = NULL;
2484         int ret = -ENOMEM;
2485
2486         if (!sbi->s_es->s_mount_opts[0])
2487                 return 0;
2488
2489         s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
2490                                 sizeof(sbi->s_es->s_mount_opts),
2491                                 GFP_KERNEL);
2492         if (!s_mount_opts)
2493                 return ret;
2494
2495         fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
2496         if (!fc)
2497                 goto out_free;
2498
2499         s_ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2500         if (!s_ctx)
2501                 goto out_free;
2502
2503         fc->fs_private = s_ctx;
2504         fc->s_fs_info = sbi;
2505
2506         ret = parse_options(fc, s_mount_opts);
2507         if (ret < 0)
2508                 goto parse_failed;
2509
2510         ret = ext4_check_opt_consistency(fc, sb);
2511         if (ret < 0) {
2512 parse_failed:
2513                 ext4_msg(sb, KERN_WARNING,
2514                          "failed to parse options in superblock: %s",
2515                          s_mount_opts);
2516                 ret = 0;
2517                 goto out_free;
2518         }
2519
2520         if (s_ctx->spec & EXT4_SPEC_JOURNAL_DEV)
2521                 m_ctx->journal_devnum = s_ctx->journal_devnum;
2522         if (s_ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)
2523                 m_ctx->journal_ioprio = s_ctx->journal_ioprio;
2524
2525         ext4_apply_options(fc, sb);
2526         ret = 0;
2527
2528 out_free:
2529         if (fc) {
2530                 ext4_fc_free(fc);
2531                 kfree(fc);
2532         }
2533         kfree(s_mount_opts);
2534         return ret;
2535 }
2536
2537 static void ext4_apply_quota_options(struct fs_context *fc,
2538                                      struct super_block *sb)
2539 {
2540 #ifdef CONFIG_QUOTA
2541         bool quota_feature = ext4_has_feature_quota(sb);
2542         struct ext4_fs_context *ctx = fc->fs_private;
2543         struct ext4_sb_info *sbi = EXT4_SB(sb);
2544         char *qname;
2545         int i;
2546
2547         if (quota_feature)
2548                 return;
2549
2550         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2551                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2552                         if (!(ctx->qname_spec & (1 << i)))
2553                                 continue;
2554
2555                         qname = ctx->s_qf_names[i]; /* May be NULL */
2556                         if (qname)
2557                                 set_opt(sb, QUOTA);
2558                         ctx->s_qf_names[i] = NULL;
2559                         qname = rcu_replace_pointer(sbi->s_qf_names[i], qname,
2560                                                 lockdep_is_held(&sb->s_umount));
2561                         if (qname)
2562                                 kfree_rcu_mightsleep(qname);
2563                 }
2564         }
2565
2566         if (ctx->spec & EXT4_SPEC_JQFMT)
2567                 sbi->s_jquota_fmt = ctx->s_jquota_fmt;
2568 #endif
2569 }
2570
2571 /*
2572  * Check quota settings consistency.
2573  */
2574 static int ext4_check_quota_consistency(struct fs_context *fc,
2575                                         struct super_block *sb)
2576 {
2577 #ifdef CONFIG_QUOTA
2578         struct ext4_fs_context *ctx = fc->fs_private;
2579         struct ext4_sb_info *sbi = EXT4_SB(sb);
2580         bool quota_feature = ext4_has_feature_quota(sb);
2581         bool quota_loaded = sb_any_quota_loaded(sb);
2582         bool usr_qf_name, grp_qf_name, usrquota, grpquota;
2583         int quota_flags, i;
2584
2585         /*
2586          * We do the test below only for project quotas. 'usrquota' and
2587          * 'grpquota' mount options are allowed even without quota feature
2588          * to support legacy quotas in quota files.
2589          */
2590         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_PRJQUOTA) &&
2591             !ext4_has_feature_project(sb)) {
2592                 ext4_msg(NULL, KERN_ERR, "Project quota feature not enabled. "
2593                          "Cannot enable project quota enforcement.");
2594                 return -EINVAL;
2595         }
2596
2597         quota_flags = EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2598                       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA;
2599         if (quota_loaded &&
2600             ctx->mask_s_mount_opt & quota_flags &&
2601             !ctx_test_mount_opt(ctx, quota_flags))
2602                 goto err_quota_change;
2603
2604         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2605
2606                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2607                         if (!(ctx->qname_spec & (1 << i)))
2608                                 continue;
2609
2610                         if (quota_loaded &&
2611                             !!sbi->s_qf_names[i] != !!ctx->s_qf_names[i])
2612                                 goto err_jquota_change;
2613
2614                         if (sbi->s_qf_names[i] && ctx->s_qf_names[i] &&
2615                             strcmp(get_qf_name(sb, sbi, i),
2616                                    ctx->s_qf_names[i]) != 0)
2617                                 goto err_jquota_specified;
2618                 }
2619
2620                 if (quota_feature) {
2621                         ext4_msg(NULL, KERN_INFO,
2622                                  "Journaled quota options ignored when "
2623                                  "QUOTA feature is enabled");
2624                         return 0;
2625                 }
2626         }
2627
2628         if (ctx->spec & EXT4_SPEC_JQFMT) {
2629                 if (sbi->s_jquota_fmt != ctx->s_jquota_fmt && quota_loaded)
2630                         goto err_jquota_change;
2631                 if (quota_feature) {
2632                         ext4_msg(NULL, KERN_INFO, "Quota format mount options "
2633                                  "ignored when QUOTA feature is enabled");
2634                         return 0;
2635                 }
2636         }
2637
2638         /* Make sure we don't mix old and new quota format */
2639         usr_qf_name = (get_qf_name(sb, sbi, USRQUOTA) ||
2640                        ctx->s_qf_names[USRQUOTA]);
2641         grp_qf_name = (get_qf_name(sb, sbi, GRPQUOTA) ||
2642                        ctx->s_qf_names[GRPQUOTA]);
2643
2644         usrquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2645                     test_opt(sb, USRQUOTA));
2646
2647         grpquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) ||
2648                     test_opt(sb, GRPQUOTA));
2649
2650         if (usr_qf_name) {
2651                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2652                 usrquota = false;
2653         }
2654         if (grp_qf_name) {
2655                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2656                 grpquota = false;
2657         }
2658
2659         if (usr_qf_name || grp_qf_name) {
2660                 if (usrquota || grpquota) {
2661                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2662                                  "format mixing");
2663                         return -EINVAL;
2664                 }
2665
2666                 if (!(ctx->spec & EXT4_SPEC_JQFMT || sbi->s_jquota_fmt)) {
2667                         ext4_msg(NULL, KERN_ERR, "journaled quota format "
2668                                  "not specified");
2669                         return -EINVAL;
2670                 }
2671         }
2672
2673         return 0;
2674
2675 err_quota_change:
2676         ext4_msg(NULL, KERN_ERR,
2677                  "Cannot change quota options when quota turned on");
2678         return -EINVAL;
2679 err_jquota_change:
2680         ext4_msg(NULL, KERN_ERR, "Cannot change journaled quota "
2681                  "options when quota turned on");
2682         return -EINVAL;
2683 err_jquota_specified:
2684         ext4_msg(NULL, KERN_ERR, "%s quota file already specified",
2685                  QTYPE2NAME(i));
2686         return -EINVAL;
2687 #else
2688         return 0;
2689 #endif
2690 }
2691
2692 static int ext4_check_test_dummy_encryption(const struct fs_context *fc,
2693                                             struct super_block *sb)
2694 {
2695         const struct ext4_fs_context *ctx = fc->fs_private;
2696         const struct ext4_sb_info *sbi = EXT4_SB(sb);
2697
2698         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy))
2699                 return 0;
2700
2701         if (!ext4_has_feature_encrypt(sb)) {
2702                 ext4_msg(NULL, KERN_WARNING,
2703                          "test_dummy_encryption requires encrypt feature");
2704                 return -EINVAL;
2705         }
2706         /*
2707          * This mount option is just for testing, and it's not worthwhile to
2708          * implement the extra complexity (e.g. RCU protection) that would be
2709          * needed to allow it to be set or changed during remount.  We do allow
2710          * it to be specified during remount, but only if there is no change.
2711          */
2712         if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2713                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2714                                                  &ctx->dummy_enc_policy))
2715                         return 0;
2716                 ext4_msg(NULL, KERN_WARNING,
2717                          "Can't set or change test_dummy_encryption on remount");
2718                 return -EINVAL;
2719         }
2720         /* Also make sure s_mount_opts didn't contain a conflicting value. */
2721         if (fscrypt_is_dummy_policy_set(&sbi->s_dummy_enc_policy)) {
2722                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2723                                                  &ctx->dummy_enc_policy))
2724                         return 0;
2725                 ext4_msg(NULL, KERN_WARNING,
2726                          "Conflicting test_dummy_encryption options");
2727                 return -EINVAL;
2728         }
2729         return 0;
2730 }
2731
2732 static void ext4_apply_test_dummy_encryption(struct ext4_fs_context *ctx,
2733                                              struct super_block *sb)
2734 {
2735         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy) ||
2736             /* if already set, it was already verified to be the same */
2737             fscrypt_is_dummy_policy_set(&EXT4_SB(sb)->s_dummy_enc_policy))
2738                 return;
2739         EXT4_SB(sb)->s_dummy_enc_policy = ctx->dummy_enc_policy;
2740         memset(&ctx->dummy_enc_policy, 0, sizeof(ctx->dummy_enc_policy));
2741         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2742 }
2743
2744 static int ext4_check_opt_consistency(struct fs_context *fc,
2745                                       struct super_block *sb)
2746 {
2747         struct ext4_fs_context *ctx = fc->fs_private;
2748         struct ext4_sb_info *sbi = fc->s_fs_info;
2749         int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2750         int err;
2751
2752         if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2753                 ext4_msg(NULL, KERN_ERR,
2754                          "Mount option(s) incompatible with ext2");
2755                 return -EINVAL;
2756         }
2757         if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2758                 ext4_msg(NULL, KERN_ERR,
2759                          "Mount option(s) incompatible with ext3");
2760                 return -EINVAL;
2761         }
2762
2763         if (ctx->s_want_extra_isize >
2764             (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2765                 ext4_msg(NULL, KERN_ERR,
2766                          "Invalid want_extra_isize %d",
2767                          ctx->s_want_extra_isize);
2768                 return -EINVAL;
2769         }
2770
2771         err = ext4_check_test_dummy_encryption(fc, sb);
2772         if (err)
2773                 return err;
2774
2775         if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2776                 if (!sbi->s_journal) {
2777                         ext4_msg(NULL, KERN_WARNING,
2778                                  "Remounting file system with no journal "
2779                                  "so ignoring journalled data option");
2780                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2781                 } else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2782                            test_opt(sb, DATA_FLAGS)) {
2783                         ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2784                                  "on remount");
2785                         return -EINVAL;
2786                 }
2787         }
2788
2789         if (is_remount) {
2790                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2791                     (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2792                         ext4_msg(NULL, KERN_ERR, "can't mount with "
2793                                  "both data=journal and dax");
2794                         return -EINVAL;
2795                 }
2796
2797                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2798                     (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2799                      (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2800 fail_dax_change_remount:
2801                         ext4_msg(NULL, KERN_ERR, "can't change "
2802                                  "dax mount option while remounting");
2803                         return -EINVAL;
2804                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2805                          (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2806                           (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2807                         goto fail_dax_change_remount;
2808                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2809                            ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2810                             (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2811                             !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2812                         goto fail_dax_change_remount;
2813                 }
2814         }
2815
2816         return ext4_check_quota_consistency(fc, sb);
2817 }
2818
2819 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2820 {
2821         struct ext4_fs_context *ctx = fc->fs_private;
2822         struct ext4_sb_info *sbi = fc->s_fs_info;
2823
2824         sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2825         sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2826         sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2827         sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2828         sb->s_flags &= ~ctx->mask_s_flags;
2829         sb->s_flags |= ctx->vals_s_flags;
2830
2831 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2832         APPLY(s_commit_interval);
2833         APPLY(s_stripe);
2834         APPLY(s_max_batch_time);
2835         APPLY(s_min_batch_time);
2836         APPLY(s_want_extra_isize);
2837         APPLY(s_inode_readahead_blks);
2838         APPLY(s_max_dir_size_kb);
2839         APPLY(s_li_wait_mult);
2840         APPLY(s_resgid);
2841         APPLY(s_resuid);
2842
2843 #ifdef CONFIG_EXT4_DEBUG
2844         APPLY(s_fc_debug_max_replay);
2845 #endif
2846
2847         ext4_apply_quota_options(fc, sb);
2848         ext4_apply_test_dummy_encryption(ctx, sb);
2849 }
2850
2851
2852 static int ext4_validate_options(struct fs_context *fc)
2853 {
2854 #ifdef CONFIG_QUOTA
2855         struct ext4_fs_context *ctx = fc->fs_private;
2856         char *usr_qf_name, *grp_qf_name;
2857
2858         usr_qf_name = ctx->s_qf_names[USRQUOTA];
2859         grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2860
2861         if (usr_qf_name || grp_qf_name) {
2862                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2863                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2864
2865                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2866                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2867
2868                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2869                     ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2870                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2871                                  "format mixing");
2872                         return -EINVAL;
2873                 }
2874         }
2875 #endif
2876         return 1;
2877 }
2878
2879 static inline void ext4_show_quota_options(struct seq_file *seq,
2880                                            struct super_block *sb)
2881 {
2882 #if defined(CONFIG_QUOTA)
2883         struct ext4_sb_info *sbi = EXT4_SB(sb);
2884         char *usr_qf_name, *grp_qf_name;
2885
2886         if (sbi->s_jquota_fmt) {
2887                 char *fmtname = "";
2888
2889                 switch (sbi->s_jquota_fmt) {
2890                 case QFMT_VFS_OLD:
2891                         fmtname = "vfsold";
2892                         break;
2893                 case QFMT_VFS_V0:
2894                         fmtname = "vfsv0";
2895                         break;
2896                 case QFMT_VFS_V1:
2897                         fmtname = "vfsv1";
2898                         break;
2899                 }
2900                 seq_printf(seq, ",jqfmt=%s", fmtname);
2901         }
2902
2903         rcu_read_lock();
2904         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2905         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2906         if (usr_qf_name)
2907                 seq_show_option(seq, "usrjquota", usr_qf_name);
2908         if (grp_qf_name)
2909                 seq_show_option(seq, "grpjquota", grp_qf_name);
2910         rcu_read_unlock();
2911 #endif
2912 }
2913
2914 static const char *token2str(int token)
2915 {
2916         const struct fs_parameter_spec *spec;
2917
2918         for (spec = ext4_param_specs; spec->name != NULL; spec++)
2919                 if (spec->opt == token && !spec->type)
2920                         break;
2921         return spec->name;
2922 }
2923
2924 /*
2925  * Show an option if
2926  *  - it's set to a non-default value OR
2927  *  - if the per-sb default is different from the global default
2928  */
2929 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2930                               int nodefs)
2931 {
2932         struct ext4_sb_info *sbi = EXT4_SB(sb);
2933         struct ext4_super_block *es = sbi->s_es;
2934         int def_errors;
2935         const struct mount_opts *m;
2936         char sep = nodefs ? '\n' : ',';
2937
2938 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2939 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2940
2941         if (sbi->s_sb_block != 1)
2942                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2943
2944         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2945                 int want_set = m->flags & MOPT_SET;
2946                 int opt_2 = m->flags & MOPT_2;
2947                 unsigned int mount_opt, def_mount_opt;
2948
2949                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2950                     m->flags & MOPT_SKIP)
2951                         continue;
2952
2953                 if (opt_2) {
2954                         mount_opt = sbi->s_mount_opt2;
2955                         def_mount_opt = sbi->s_def_mount_opt2;
2956                 } else {
2957                         mount_opt = sbi->s_mount_opt;
2958                         def_mount_opt = sbi->s_def_mount_opt;
2959                 }
2960                 /* skip if same as the default */
2961                 if (!nodefs && !(m->mount_opt & (mount_opt ^ def_mount_opt)))
2962                         continue;
2963                 /* select Opt_noFoo vs Opt_Foo */
2964                 if ((want_set &&
2965                      (mount_opt & m->mount_opt) != m->mount_opt) ||
2966                     (!want_set && (mount_opt & m->mount_opt)))
2967                         continue;
2968                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2969         }
2970
2971         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2972             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2973                 SEQ_OPTS_PRINT("resuid=%u",
2974                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2975         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2976             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2977                 SEQ_OPTS_PRINT("resgid=%u",
2978                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2979         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2980         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2981                 SEQ_OPTS_PUTS("errors=remount-ro");
2982         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2983                 SEQ_OPTS_PUTS("errors=continue");
2984         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2985                 SEQ_OPTS_PUTS("errors=panic");
2986         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2987                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2988         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2989                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2990         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2991                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2992         if (nodefs || sbi->s_stripe)
2993                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2994         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2995                         (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
2996                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2997                         SEQ_OPTS_PUTS("data=journal");
2998                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2999                         SEQ_OPTS_PUTS("data=ordered");
3000                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
3001                         SEQ_OPTS_PUTS("data=writeback");
3002         }
3003         if (nodefs ||
3004             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
3005                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
3006                                sbi->s_inode_readahead_blks);
3007
3008         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
3009                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
3010                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
3011         if (nodefs || sbi->s_max_dir_size_kb)
3012                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
3013         if (test_opt(sb, DATA_ERR_ABORT))
3014                 SEQ_OPTS_PUTS("data_err=abort");
3015
3016         fscrypt_show_test_dummy_encryption(seq, sep, sb);
3017
3018         if (sb->s_flags & SB_INLINECRYPT)
3019                 SEQ_OPTS_PUTS("inlinecrypt");
3020
3021         if (test_opt(sb, DAX_ALWAYS)) {
3022                 if (IS_EXT2_SB(sb))
3023                         SEQ_OPTS_PUTS("dax");
3024                 else
3025                         SEQ_OPTS_PUTS("dax=always");
3026         } else if (test_opt2(sb, DAX_NEVER)) {
3027                 SEQ_OPTS_PUTS("dax=never");
3028         } else if (test_opt2(sb, DAX_INODE)) {
3029                 SEQ_OPTS_PUTS("dax=inode");
3030         }
3031
3032         if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3033                         !test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3034                 SEQ_OPTS_PUTS("mb_optimize_scan=0");
3035         } else if (sbi->s_groups_count < MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3036                         test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3037                 SEQ_OPTS_PUTS("mb_optimize_scan=1");
3038         }
3039
3040         if (nodefs && !test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS))
3041                 SEQ_OPTS_PUTS("prefetch_block_bitmaps");
3042
3043         ext4_show_quota_options(seq, sb);
3044         return 0;
3045 }
3046
3047 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
3048 {
3049         return _ext4_show_options(seq, root->d_sb, 0);
3050 }
3051
3052 int ext4_seq_options_show(struct seq_file *seq, void *offset)
3053 {
3054         struct super_block *sb = seq->private;
3055         int rc;
3056
3057         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
3058         rc = _ext4_show_options(seq, sb, 1);
3059         seq_putc(seq, '\n');
3060         return rc;
3061 }
3062
3063 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3064                             int read_only)
3065 {
3066         struct ext4_sb_info *sbi = EXT4_SB(sb);
3067         int err = 0;
3068
3069         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3070                 ext4_msg(sb, KERN_ERR, "revision level too high, "
3071                          "forcing read-only mode");
3072                 err = -EROFS;
3073                 goto done;
3074         }
3075         if (read_only)
3076                 goto done;
3077         if (!(sbi->s_mount_state & EXT4_VALID_FS))
3078                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3079                          "running e2fsck is recommended");
3080         else if (sbi->s_mount_state & EXT4_ERROR_FS)
3081                 ext4_msg(sb, KERN_WARNING,
3082                          "warning: mounting fs with errors, "
3083                          "running e2fsck is recommended");
3084         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3085                  le16_to_cpu(es->s_mnt_count) >=
3086                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3087                 ext4_msg(sb, KERN_WARNING,
3088                          "warning: maximal mount count reached, "
3089                          "running e2fsck is recommended");
3090         else if (le32_to_cpu(es->s_checkinterval) &&
3091                  (ext4_get_tstamp(es, s_lastcheck) +
3092                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3093                 ext4_msg(sb, KERN_WARNING,
3094                          "warning: checktime reached, "
3095                          "running e2fsck is recommended");
3096         if (!sbi->s_journal)
3097                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3098         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3099                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3100         le16_add_cpu(&es->s_mnt_count, 1);
3101         ext4_update_tstamp(es, s_mtime);
3102         if (sbi->s_journal) {
3103                 ext4_set_feature_journal_needs_recovery(sb);
3104                 if (ext4_has_feature_orphan_file(sb))
3105                         ext4_set_feature_orphan_present(sb);
3106         }
3107
3108         err = ext4_commit_super(sb);
3109 done:
3110         if (test_opt(sb, DEBUG))
3111                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3112                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3113                         sb->s_blocksize,
3114                         sbi->s_groups_count,
3115                         EXT4_BLOCKS_PER_GROUP(sb),
3116                         EXT4_INODES_PER_GROUP(sb),
3117                         sbi->s_mount_opt, sbi->s_mount_opt2);
3118         return err;
3119 }
3120
3121 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3122 {
3123         struct ext4_sb_info *sbi = EXT4_SB(sb);
3124         struct flex_groups **old_groups, **new_groups;
3125         int size, i, j;
3126
3127         if (!sbi->s_log_groups_per_flex)
3128                 return 0;
3129
3130         size = ext4_flex_group(sbi, ngroup - 1) + 1;
3131         if (size <= sbi->s_flex_groups_allocated)
3132                 return 0;
3133
3134         new_groups = kvzalloc(roundup_pow_of_two(size *
3135                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3136         if (!new_groups) {
3137                 ext4_msg(sb, KERN_ERR,
3138                          "not enough memory for %d flex group pointers", size);
3139                 return -ENOMEM;
3140         }
3141         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3142                 new_groups[i] = kvzalloc(roundup_pow_of_two(
3143                                          sizeof(struct flex_groups)),
3144                                          GFP_KERNEL);
3145                 if (!new_groups[i]) {
3146                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
3147                                 kvfree(new_groups[j]);
3148                         kvfree(new_groups);
3149                         ext4_msg(sb, KERN_ERR,
3150                                  "not enough memory for %d flex groups", size);
3151                         return -ENOMEM;
3152                 }
3153         }
3154         rcu_read_lock();
3155         old_groups = rcu_dereference(sbi->s_flex_groups);
3156         if (old_groups)
3157                 memcpy(new_groups, old_groups,
3158                        (sbi->s_flex_groups_allocated *
3159                         sizeof(struct flex_groups *)));
3160         rcu_read_unlock();
3161         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3162         sbi->s_flex_groups_allocated = size;
3163         if (old_groups)
3164                 ext4_kvfree_array_rcu(old_groups);
3165         return 0;
3166 }
3167
3168 static int ext4_fill_flex_info(struct super_block *sb)
3169 {
3170         struct ext4_sb_info *sbi = EXT4_SB(sb);
3171         struct ext4_group_desc *gdp = NULL;
3172         struct flex_groups *fg;
3173         ext4_group_t flex_group;
3174         int i, err;
3175
3176         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3177         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3178                 sbi->s_log_groups_per_flex = 0;
3179                 return 1;
3180         }
3181
3182         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3183         if (err)
3184                 goto failed;
3185
3186         for (i = 0; i < sbi->s_groups_count; i++) {
3187                 gdp = ext4_get_group_desc(sb, i, NULL);
3188
3189                 flex_group = ext4_flex_group(sbi, i);
3190                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3191                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3192                 atomic64_add(ext4_free_group_clusters(sb, gdp),
3193                              &fg->free_clusters);
3194                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3195         }
3196
3197         return 1;
3198 failed:
3199         return 0;
3200 }
3201
3202 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3203                                    struct ext4_group_desc *gdp)
3204 {
3205         int offset = offsetof(struct ext4_group_desc, bg_checksum);
3206         __u16 crc = 0;
3207         __le32 le_group = cpu_to_le32(block_group);
3208         struct ext4_sb_info *sbi = EXT4_SB(sb);
3209
3210         if (ext4_has_metadata_csum(sbi->s_sb)) {
3211                 /* Use new metadata_csum algorithm */
3212                 __u32 csum32;
3213                 __u16 dummy_csum = 0;
3214
3215                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
3216                                      sizeof(le_group));
3217                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
3218                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
3219                                      sizeof(dummy_csum));
3220                 offset += sizeof(dummy_csum);
3221                 if (offset < sbi->s_desc_size)
3222                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
3223                                              sbi->s_desc_size - offset);
3224
3225                 crc = csum32 & 0xFFFF;
3226                 goto out;
3227         }
3228
3229         /* old crc16 code */
3230         if (!ext4_has_feature_gdt_csum(sb))
3231                 return 0;
3232
3233         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3234         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3235         crc = crc16(crc, (__u8 *)gdp, offset);
3236         offset += sizeof(gdp->bg_checksum); /* skip checksum */
3237         /* for checksum of struct ext4_group_desc do the rest...*/
3238         if (ext4_has_feature_64bit(sb) && offset < sbi->s_desc_size)
3239                 crc = crc16(crc, (__u8 *)gdp + offset,
3240                             sbi->s_desc_size - offset);
3241
3242 out:
3243         return cpu_to_le16(crc);
3244 }
3245
3246 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3247                                 struct ext4_group_desc *gdp)
3248 {
3249         if (ext4_has_group_desc_csum(sb) &&
3250             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3251                 return 0;
3252
3253         return 1;
3254 }
3255
3256 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3257                               struct ext4_group_desc *gdp)
3258 {
3259         if (!ext4_has_group_desc_csum(sb))
3260                 return;
3261         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3262 }
3263
3264 /* Called at mount-time, super-block is locked */
3265 static int ext4_check_descriptors(struct super_block *sb,
3266                                   ext4_fsblk_t sb_block,
3267                                   ext4_group_t *first_not_zeroed)
3268 {
3269         struct ext4_sb_info *sbi = EXT4_SB(sb);
3270         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3271         ext4_fsblk_t last_block;
3272         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3273         ext4_fsblk_t block_bitmap;
3274         ext4_fsblk_t inode_bitmap;
3275         ext4_fsblk_t inode_table;
3276         int flexbg_flag = 0;
3277         ext4_group_t i, grp = sbi->s_groups_count;
3278
3279         if (ext4_has_feature_flex_bg(sb))
3280                 flexbg_flag = 1;
3281
3282         ext4_debug("Checking group descriptors");
3283
3284         for (i = 0; i < sbi->s_groups_count; i++) {
3285                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3286
3287                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
3288                         last_block = ext4_blocks_count(sbi->s_es) - 1;
3289                 else
3290                         last_block = first_block +
3291                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
3292
3293                 if ((grp == sbi->s_groups_count) &&
3294                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3295                         grp = i;
3296
3297                 block_bitmap = ext4_block_bitmap(sb, gdp);
3298                 if (block_bitmap == sb_block) {
3299                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3300                                  "Block bitmap for group %u overlaps "
3301                                  "superblock", i);
3302                         if (!sb_rdonly(sb))
3303                                 return 0;
3304                 }
3305                 if (block_bitmap >= sb_block + 1 &&
3306                     block_bitmap <= last_bg_block) {
3307                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3308                                  "Block bitmap for group %u overlaps "
3309                                  "block group descriptors", i);
3310                         if (!sb_rdonly(sb))
3311                                 return 0;
3312                 }
3313                 if (block_bitmap < first_block || block_bitmap > last_block) {
3314                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3315                                "Block bitmap for group %u not in group "
3316                                "(block %llu)!", i, block_bitmap);
3317                         return 0;
3318                 }
3319                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
3320                 if (inode_bitmap == sb_block) {
3321                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3322                                  "Inode bitmap for group %u overlaps "
3323                                  "superblock", i);
3324                         if (!sb_rdonly(sb))
3325                                 return 0;
3326                 }
3327                 if (inode_bitmap >= sb_block + 1 &&
3328                     inode_bitmap <= last_bg_block) {
3329                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3330                                  "Inode bitmap for group %u overlaps "
3331                                  "block group descriptors", i);
3332                         if (!sb_rdonly(sb))
3333                                 return 0;
3334                 }
3335                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
3336                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3337                                "Inode bitmap for group %u not in group "
3338                                "(block %llu)!", i, inode_bitmap);
3339                         return 0;
3340                 }
3341                 inode_table = ext4_inode_table(sb, gdp);
3342                 if (inode_table == sb_block) {
3343                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3344                                  "Inode table for group %u overlaps "
3345                                  "superblock", i);
3346                         if (!sb_rdonly(sb))
3347                                 return 0;
3348                 }
3349                 if (inode_table >= sb_block + 1 &&
3350                     inode_table <= last_bg_block) {
3351                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3352                                  "Inode table for group %u overlaps "
3353                                  "block group descriptors", i);
3354                         if (!sb_rdonly(sb))
3355                                 return 0;
3356                 }
3357                 if (inode_table < first_block ||
3358                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
3359                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3360                                "Inode table for group %u not in group "
3361                                "(block %llu)!", i, inode_table);
3362                         return 0;
3363                 }
3364                 ext4_lock_group(sb, i);
3365                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3366                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3367                                  "Checksum for group %u failed (%u!=%u)",
3368                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3369                                      gdp)), le16_to_cpu(gdp->bg_checksum));
3370                         if (!sb_rdonly(sb)) {
3371                                 ext4_unlock_group(sb, i);
3372                                 return 0;
3373                         }
3374                 }
3375                 ext4_unlock_group(sb, i);
3376                 if (!flexbg_flag)
3377                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
3378         }
3379         if (NULL != first_not_zeroed)
3380                 *first_not_zeroed = grp;
3381         return 1;
3382 }
3383
3384 /*
3385  * Maximal extent format file size.
3386  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3387  * extent format containers, within a sector_t, and within i_blocks
3388  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3389  * so that won't be a limiting factor.
3390  *
3391  * However there is other limiting factor. We do store extents in the form
3392  * of starting block and length, hence the resulting length of the extent
3393  * covering maximum file size must fit into on-disk format containers as
3394  * well. Given that length is always by 1 unit bigger than max unit (because
3395  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3396  *
3397  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3398  */
3399 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3400 {
3401         loff_t res;
3402         loff_t upper_limit = MAX_LFS_FILESIZE;
3403
3404         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3405
3406         if (!has_huge_files) {
3407                 upper_limit = (1LL << 32) - 1;
3408
3409                 /* total blocks in file system block size */
3410                 upper_limit >>= (blkbits - 9);
3411                 upper_limit <<= blkbits;
3412         }
3413
3414         /*
3415          * 32-bit extent-start container, ee_block. We lower the maxbytes
3416          * by one fs block, so ee_len can cover the extent of maximum file
3417          * size
3418          */
3419         res = (1LL << 32) - 1;
3420         res <<= blkbits;
3421
3422         /* Sanity check against vm- & vfs- imposed limits */
3423         if (res > upper_limit)
3424                 res = upper_limit;
3425
3426         return res;
3427 }
3428
3429 /*
3430  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3431  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3432  * We need to be 1 filesystem block less than the 2^48 sector limit.
3433  */
3434 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3435 {
3436         loff_t upper_limit, res = EXT4_NDIR_BLOCKS;
3437         int meta_blocks;
3438         unsigned int ppb = 1 << (bits - 2);
3439
3440         /*
3441          * This is calculated to be the largest file size for a dense, block
3442          * mapped file such that the file's total number of 512-byte sectors,
3443          * including data and all indirect blocks, does not exceed (2^48 - 1).
3444          *
3445          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3446          * number of 512-byte sectors of the file.
3447          */
3448         if (!has_huge_files) {
3449                 /*
3450                  * !has_huge_files or implies that the inode i_block field
3451                  * represents total file blocks in 2^32 512-byte sectors ==
3452                  * size of vfs inode i_blocks * 8
3453                  */
3454                 upper_limit = (1LL << 32) - 1;
3455
3456                 /* total blocks in file system block size */
3457                 upper_limit >>= (bits - 9);
3458
3459         } else {
3460                 /*
3461                  * We use 48 bit ext4_inode i_blocks
3462                  * With EXT4_HUGE_FILE_FL set the i_blocks
3463                  * represent total number of blocks in
3464                  * file system block size
3465                  */
3466                 upper_limit = (1LL << 48) - 1;
3467
3468         }
3469
3470         /* Compute how many blocks we can address by block tree */
3471         res += ppb;
3472         res += ppb * ppb;
3473         res += ((loff_t)ppb) * ppb * ppb;
3474         /* Compute how many metadata blocks are needed */
3475         meta_blocks = 1;
3476         meta_blocks += 1 + ppb;
3477         meta_blocks += 1 + ppb + ppb * ppb;
3478         /* Does block tree limit file size? */
3479         if (res + meta_blocks <= upper_limit)
3480                 goto check_lfs;
3481
3482         res = upper_limit;
3483         /* How many metadata blocks are needed for addressing upper_limit? */
3484         upper_limit -= EXT4_NDIR_BLOCKS;
3485         /* indirect blocks */
3486         meta_blocks = 1;
3487         upper_limit -= ppb;
3488         /* double indirect blocks */
3489         if (upper_limit < ppb * ppb) {
3490                 meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb);
3491                 res -= meta_blocks;
3492                 goto check_lfs;
3493         }
3494         meta_blocks += 1 + ppb;
3495         upper_limit -= ppb * ppb;
3496         /* tripple indirect blocks for the rest */
3497         meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb) +
3498                 DIV_ROUND_UP_ULL(upper_limit, ppb*ppb);
3499         res -= meta_blocks;
3500 check_lfs:
3501         res <<= bits;
3502         if (res > MAX_LFS_FILESIZE)
3503                 res = MAX_LFS_FILESIZE;
3504
3505         return res;
3506 }
3507
3508 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3509                                    ext4_fsblk_t logical_sb_block, int nr)
3510 {
3511         struct ext4_sb_info *sbi = EXT4_SB(sb);
3512         ext4_group_t bg, first_meta_bg;
3513         int has_super = 0;
3514
3515         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3516
3517         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3518                 return logical_sb_block + nr + 1;
3519         bg = sbi->s_desc_per_block * nr;
3520         if (ext4_bg_has_super(sb, bg))
3521                 has_super = 1;
3522
3523         /*
3524          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3525          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3526          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3527          * compensate.
3528          */
3529         if (sb->s_blocksize == 1024 && nr == 0 &&
3530             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3531                 has_super++;
3532
3533         return (has_super + ext4_group_first_block_no(sb, bg));
3534 }
3535
3536 /**
3537  * ext4_get_stripe_size: Get the stripe size.
3538  * @sbi: In memory super block info
3539  *
3540  * If we have specified it via mount option, then
3541  * use the mount option value. If the value specified at mount time is
3542  * greater than the blocks per group use the super block value.
3543  * If the super block value is greater than blocks per group return 0.
3544  * Allocator needs it be less than blocks per group.
3545  *
3546  */
3547 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3548 {
3549         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3550         unsigned long stripe_width =
3551                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3552         int ret;
3553
3554         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3555                 ret = sbi->s_stripe;
3556         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3557                 ret = stripe_width;
3558         else if (stride && stride <= sbi->s_blocks_per_group)
3559                 ret = stride;
3560         else
3561                 ret = 0;
3562
3563         /*
3564          * If the stripe width is 1, this makes no sense and
3565          * we set it to 0 to turn off stripe handling code.
3566          */
3567         if (ret <= 1)
3568                 ret = 0;
3569
3570         return ret;
3571 }
3572
3573 /*
3574  * Check whether this filesystem can be mounted based on
3575  * the features present and the RDONLY/RDWR mount requested.
3576  * Returns 1 if this filesystem can be mounted as requested,
3577  * 0 if it cannot be.
3578  */
3579 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3580 {
3581         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3582                 ext4_msg(sb, KERN_ERR,
3583                         "Couldn't mount because of "
3584                         "unsupported optional features (%x)",
3585                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3586                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3587                 return 0;
3588         }
3589
3590         if (!IS_ENABLED(CONFIG_UNICODE) && ext4_has_feature_casefold(sb)) {
3591                 ext4_msg(sb, KERN_ERR,
3592                          "Filesystem with casefold feature cannot be "
3593                          "mounted without CONFIG_UNICODE");
3594                 return 0;
3595         }
3596
3597         if (readonly)
3598                 return 1;
3599
3600         if (ext4_has_feature_readonly(sb)) {
3601                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3602                 sb->s_flags |= SB_RDONLY;
3603                 return 1;
3604         }
3605
3606         /* Check that feature set is OK for a read-write mount */
3607         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3608                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3609                          "unsupported optional features (%x)",
3610                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3611                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3612                 return 0;
3613         }
3614         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3615                 ext4_msg(sb, KERN_ERR,
3616                          "Can't support bigalloc feature without "
3617                          "extents feature\n");
3618                 return 0;
3619         }
3620
3621 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3622         if (!readonly && (ext4_has_feature_quota(sb) ||
3623                           ext4_has_feature_project(sb))) {
3624                 ext4_msg(sb, KERN_ERR,
3625                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3626                 return 0;
3627         }
3628 #endif  /* CONFIG_QUOTA */
3629         return 1;
3630 }
3631
3632 /*
3633  * This function is called once a day if we have errors logged
3634  * on the file system
3635  */
3636 static void print_daily_error_info(struct timer_list *t)
3637 {
3638         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3639         struct super_block *sb = sbi->s_sb;
3640         struct ext4_super_block *es = sbi->s_es;
3641
3642         if (es->s_error_count)
3643                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3644                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3645                          le32_to_cpu(es->s_error_count));
3646         if (es->s_first_error_time) {
3647                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3648                        sb->s_id,
3649                        ext4_get_tstamp(es, s_first_error_time),
3650                        (int) sizeof(es->s_first_error_func),
3651                        es->s_first_error_func,
3652                        le32_to_cpu(es->s_first_error_line));
3653                 if (es->s_first_error_ino)
3654                         printk(KERN_CONT ": inode %u",
3655                                le32_to_cpu(es->s_first_error_ino));
3656                 if (es->s_first_error_block)
3657                         printk(KERN_CONT ": block %llu", (unsigned long long)
3658                                le64_to_cpu(es->s_first_error_block));
3659                 printk(KERN_CONT "\n");
3660         }
3661         if (es->s_last_error_time) {
3662                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3663                        sb->s_id,
3664                        ext4_get_tstamp(es, s_last_error_time),
3665                        (int) sizeof(es->s_last_error_func),
3666                        es->s_last_error_func,
3667                        le32_to_cpu(es->s_last_error_line));
3668                 if (es->s_last_error_ino)
3669                         printk(KERN_CONT ": inode %u",
3670                                le32_to_cpu(es->s_last_error_ino));
3671                 if (es->s_last_error_block)
3672                         printk(KERN_CONT ": block %llu", (unsigned long long)
3673                                le64_to_cpu(es->s_last_error_block));
3674                 printk(KERN_CONT "\n");
3675         }
3676         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3677 }
3678
3679 /* Find next suitable group and run ext4_init_inode_table */
3680 static int ext4_run_li_request(struct ext4_li_request *elr)
3681 {
3682         struct ext4_group_desc *gdp = NULL;
3683         struct super_block *sb = elr->lr_super;
3684         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3685         ext4_group_t group = elr->lr_next_group;
3686         unsigned int prefetch_ios = 0;
3687         int ret = 0;
3688         int nr = EXT4_SB(sb)->s_mb_prefetch;
3689         u64 start_time;
3690
3691         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3692                 elr->lr_next_group = ext4_mb_prefetch(sb, group, nr, &prefetch_ios);
3693                 ext4_mb_prefetch_fini(sb, elr->lr_next_group, nr);
3694                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group, nr);
3695                 if (group >= elr->lr_next_group) {
3696                         ret = 1;
3697                         if (elr->lr_first_not_zeroed != ngroups &&
3698                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3699                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3700                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3701                                 ret = 0;
3702                         }
3703                 }
3704                 return ret;
3705         }
3706
3707         for (; group < ngroups; group++) {
3708                 gdp = ext4_get_group_desc(sb, group, NULL);
3709                 if (!gdp) {
3710                         ret = 1;
3711                         break;
3712                 }
3713
3714                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3715                         break;
3716         }
3717
3718         if (group >= ngroups)
3719                 ret = 1;
3720
3721         if (!ret) {
3722                 start_time = ktime_get_ns();
3723                 ret = ext4_init_inode_table(sb, group,
3724                                             elr->lr_timeout ? 0 : 1);
3725                 trace_ext4_lazy_itable_init(sb, group);
3726                 if (elr->lr_timeout == 0) {
3727                         elr->lr_timeout = nsecs_to_jiffies((ktime_get_ns() - start_time) *
3728                                 EXT4_SB(elr->lr_super)->s_li_wait_mult);
3729                 }
3730                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3731                 elr->lr_next_group = group + 1;
3732         }
3733         return ret;
3734 }
3735
3736 /*
3737  * Remove lr_request from the list_request and free the
3738  * request structure. Should be called with li_list_mtx held
3739  */
3740 static void ext4_remove_li_request(struct ext4_li_request *elr)
3741 {
3742         if (!elr)
3743                 return;
3744
3745         list_del(&elr->lr_request);
3746         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3747         kfree(elr);
3748 }
3749
3750 static void ext4_unregister_li_request(struct super_block *sb)
3751 {
3752         mutex_lock(&ext4_li_mtx);
3753         if (!ext4_li_info) {
3754                 mutex_unlock(&ext4_li_mtx);
3755                 return;
3756         }
3757
3758         mutex_lock(&ext4_li_info->li_list_mtx);
3759         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3760         mutex_unlock(&ext4_li_info->li_list_mtx);
3761         mutex_unlock(&ext4_li_mtx);
3762 }
3763
3764 static struct task_struct *ext4_lazyinit_task;
3765
3766 /*
3767  * This is the function where ext4lazyinit thread lives. It walks
3768  * through the request list searching for next scheduled filesystem.
3769  * When such a fs is found, run the lazy initialization request
3770  * (ext4_rn_li_request) and keep track of the time spend in this
3771  * function. Based on that time we compute next schedule time of
3772  * the request. When walking through the list is complete, compute
3773  * next waking time and put itself into sleep.
3774  */
3775 static int ext4_lazyinit_thread(void *arg)
3776 {
3777         struct ext4_lazy_init *eli = arg;
3778         struct list_head *pos, *n;
3779         struct ext4_li_request *elr;
3780         unsigned long next_wakeup, cur;
3781
3782         BUG_ON(NULL == eli);
3783         set_freezable();
3784
3785 cont_thread:
3786         while (true) {
3787                 bool next_wakeup_initialized = false;
3788
3789                 next_wakeup = 0;
3790                 mutex_lock(&eli->li_list_mtx);
3791                 if (list_empty(&eli->li_request_list)) {
3792                         mutex_unlock(&eli->li_list_mtx);
3793                         goto exit_thread;
3794                 }
3795                 list_for_each_safe(pos, n, &eli->li_request_list) {
3796                         int err = 0;
3797                         int progress = 0;
3798                         elr = list_entry(pos, struct ext4_li_request,
3799                                          lr_request);
3800
3801                         if (time_before(jiffies, elr->lr_next_sched)) {
3802                                 if (!next_wakeup_initialized ||
3803                                     time_before(elr->lr_next_sched, next_wakeup)) {
3804                                         next_wakeup = elr->lr_next_sched;
3805                                         next_wakeup_initialized = true;
3806                                 }
3807                                 continue;
3808                         }
3809                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3810                                 if (sb_start_write_trylock(elr->lr_super)) {
3811                                         progress = 1;
3812                                         /*
3813                                          * We hold sb->s_umount, sb can not
3814                                          * be removed from the list, it is
3815                                          * now safe to drop li_list_mtx
3816                                          */
3817                                         mutex_unlock(&eli->li_list_mtx);
3818                                         err = ext4_run_li_request(elr);
3819                                         sb_end_write(elr->lr_super);
3820                                         mutex_lock(&eli->li_list_mtx);
3821                                         n = pos->next;
3822                                 }
3823                                 up_read((&elr->lr_super->s_umount));
3824                         }
3825                         /* error, remove the lazy_init job */
3826                         if (err) {
3827                                 ext4_remove_li_request(elr);
3828                                 continue;
3829                         }
3830                         if (!progress) {
3831                                 elr->lr_next_sched = jiffies +
3832                                         get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3833                         }
3834                         if (!next_wakeup_initialized ||
3835                             time_before(elr->lr_next_sched, next_wakeup)) {
3836                                 next_wakeup = elr->lr_next_sched;
3837                                 next_wakeup_initialized = true;
3838                         }
3839                 }
3840                 mutex_unlock(&eli->li_list_mtx);
3841
3842                 try_to_freeze();
3843
3844                 cur = jiffies;
3845                 if (!next_wakeup_initialized || time_after_eq(cur, next_wakeup)) {
3846                         cond_resched();
3847                         continue;
3848                 }
3849
3850                 schedule_timeout_interruptible(next_wakeup - cur);
3851
3852                 if (kthread_should_stop()) {
3853                         ext4_clear_request_list();
3854                         goto exit_thread;
3855                 }
3856         }
3857
3858 exit_thread:
3859         /*
3860          * It looks like the request list is empty, but we need
3861          * to check it under the li_list_mtx lock, to prevent any
3862          * additions into it, and of course we should lock ext4_li_mtx
3863          * to atomically free the list and ext4_li_info, because at
3864          * this point another ext4 filesystem could be registering
3865          * new one.
3866          */
3867         mutex_lock(&ext4_li_mtx);
3868         mutex_lock(&eli->li_list_mtx);
3869         if (!list_empty(&eli->li_request_list)) {
3870                 mutex_unlock(&eli->li_list_mtx);
3871                 mutex_unlock(&ext4_li_mtx);
3872                 goto cont_thread;
3873         }
3874         mutex_unlock(&eli->li_list_mtx);
3875         kfree(ext4_li_info);
3876         ext4_li_info = NULL;
3877         mutex_unlock(&ext4_li_mtx);
3878
3879         return 0;
3880 }
3881
3882 static void ext4_clear_request_list(void)
3883 {
3884         struct list_head *pos, *n;
3885         struct ext4_li_request *elr;
3886
3887         mutex_lock(&ext4_li_info->li_list_mtx);
3888         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3889                 elr = list_entry(pos, struct ext4_li_request,
3890                                  lr_request);
3891                 ext4_remove_li_request(elr);
3892         }
3893         mutex_unlock(&ext4_li_info->li_list_mtx);
3894 }
3895
3896 static int ext4_run_lazyinit_thread(void)
3897 {
3898         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3899                                          ext4_li_info, "ext4lazyinit");
3900         if (IS_ERR(ext4_lazyinit_task)) {
3901                 int err = PTR_ERR(ext4_lazyinit_task);
3902                 ext4_clear_request_list();
3903                 kfree(ext4_li_info);
3904                 ext4_li_info = NULL;
3905                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3906                                  "initialization thread\n",
3907                                  err);
3908                 return err;
3909         }
3910         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3911         return 0;
3912 }
3913
3914 /*
3915  * Check whether it make sense to run itable init. thread or not.
3916  * If there is at least one uninitialized inode table, return
3917  * corresponding group number, else the loop goes through all
3918  * groups and return total number of groups.
3919  */
3920 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3921 {
3922         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3923         struct ext4_group_desc *gdp = NULL;
3924
3925         if (!ext4_has_group_desc_csum(sb))
3926                 return ngroups;
3927
3928         for (group = 0; group < ngroups; group++) {
3929                 gdp = ext4_get_group_desc(sb, group, NULL);
3930                 if (!gdp)
3931                         continue;
3932
3933                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3934                         break;
3935         }
3936
3937         return group;
3938 }
3939
3940 static int ext4_li_info_new(void)
3941 {
3942         struct ext4_lazy_init *eli = NULL;
3943
3944         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3945         if (!eli)
3946                 return -ENOMEM;
3947
3948         INIT_LIST_HEAD(&eli->li_request_list);
3949         mutex_init(&eli->li_list_mtx);
3950
3951         eli->li_state |= EXT4_LAZYINIT_QUIT;
3952
3953         ext4_li_info = eli;
3954
3955         return 0;
3956 }
3957
3958 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3959                                             ext4_group_t start)
3960 {
3961         struct ext4_li_request *elr;
3962
3963         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3964         if (!elr)
3965                 return NULL;
3966
3967         elr->lr_super = sb;
3968         elr->lr_first_not_zeroed = start;
3969         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3970                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3971                 elr->lr_next_group = start;
3972         } else {
3973                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3974         }
3975
3976         /*
3977          * Randomize first schedule time of the request to
3978          * spread the inode table initialization requests
3979          * better.
3980          */
3981         elr->lr_next_sched = jiffies + get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3982         return elr;
3983 }
3984
3985 int ext4_register_li_request(struct super_block *sb,
3986                              ext4_group_t first_not_zeroed)
3987 {
3988         struct ext4_sb_info *sbi = EXT4_SB(sb);
3989         struct ext4_li_request *elr = NULL;
3990         ext4_group_t ngroups = sbi->s_groups_count;
3991         int ret = 0;
3992
3993         mutex_lock(&ext4_li_mtx);
3994         if (sbi->s_li_request != NULL) {
3995                 /*
3996                  * Reset timeout so it can be computed again, because
3997                  * s_li_wait_mult might have changed.
3998                  */
3999                 sbi->s_li_request->lr_timeout = 0;
4000                 goto out;
4001         }
4002
4003         if (sb_rdonly(sb) ||
4004             (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
4005              (first_not_zeroed == ngroups || !test_opt(sb, INIT_INODE_TABLE))))
4006                 goto out;
4007
4008         elr = ext4_li_request_new(sb, first_not_zeroed);
4009         if (!elr) {
4010                 ret = -ENOMEM;
4011                 goto out;
4012         }
4013
4014         if (NULL == ext4_li_info) {
4015                 ret = ext4_li_info_new();
4016                 if (ret)
4017                         goto out;
4018         }
4019
4020         mutex_lock(&ext4_li_info->li_list_mtx);
4021         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
4022         mutex_unlock(&ext4_li_info->li_list_mtx);
4023
4024         sbi->s_li_request = elr;
4025         /*
4026          * set elr to NULL here since it has been inserted to
4027          * the request_list and the removal and free of it is
4028          * handled by ext4_clear_request_list from now on.
4029          */
4030         elr = NULL;
4031
4032         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
4033                 ret = ext4_run_lazyinit_thread();
4034                 if (ret)
4035                         goto out;
4036         }
4037 out:
4038         mutex_unlock(&ext4_li_mtx);
4039         if (ret)
4040                 kfree(elr);
4041         return ret;
4042 }
4043
4044 /*
4045  * We do not need to lock anything since this is called on
4046  * module unload.
4047  */
4048 static void ext4_destroy_lazyinit_thread(void)
4049 {
4050         /*
4051          * If thread exited earlier
4052          * there's nothing to be done.
4053          */
4054         if (!ext4_li_info || !ext4_lazyinit_task)
4055                 return;
4056
4057         kthread_stop(ext4_lazyinit_task);
4058 }
4059
4060 static int set_journal_csum_feature_set(struct super_block *sb)
4061 {
4062         int ret = 1;
4063         int compat, incompat;
4064         struct ext4_sb_info *sbi = EXT4_SB(sb);
4065
4066         if (ext4_has_metadata_csum(sb)) {
4067                 /* journal checksum v3 */
4068                 compat = 0;
4069                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4070         } else {
4071                 /* journal checksum v1 */
4072                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4073                 incompat = 0;
4074         }
4075
4076         jbd2_journal_clear_features(sbi->s_journal,
4077                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4078                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4079                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
4080         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4081                 ret = jbd2_journal_set_features(sbi->s_journal,
4082                                 compat, 0,
4083                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4084                                 incompat);
4085         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4086                 ret = jbd2_journal_set_features(sbi->s_journal,
4087                                 compat, 0,
4088                                 incompat);
4089                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4090                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4091         } else {
4092                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4093                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4094         }
4095
4096         return ret;
4097 }
4098
4099 /*
4100  * Note: calculating the overhead so we can be compatible with
4101  * historical BSD practice is quite difficult in the face of
4102  * clusters/bigalloc.  This is because multiple metadata blocks from
4103  * different block group can end up in the same allocation cluster.
4104  * Calculating the exact overhead in the face of clustered allocation
4105  * requires either O(all block bitmaps) in memory or O(number of block
4106  * groups**2) in time.  We will still calculate the superblock for
4107  * older file systems --- and if we come across with a bigalloc file
4108  * system with zero in s_overhead_clusters the estimate will be close to
4109  * correct especially for very large cluster sizes --- but for newer
4110  * file systems, it's better to calculate this figure once at mkfs
4111  * time, and store it in the superblock.  If the superblock value is
4112  * present (even for non-bigalloc file systems), we will use it.
4113  */
4114 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4115                           char *buf)
4116 {
4117         struct ext4_sb_info     *sbi = EXT4_SB(sb);
4118         struct ext4_group_desc  *gdp;
4119         ext4_fsblk_t            first_block, last_block, b;
4120         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
4121         int                     s, j, count = 0;
4122         int                     has_super = ext4_bg_has_super(sb, grp);
4123
4124         if (!ext4_has_feature_bigalloc(sb))
4125                 return (has_super + ext4_bg_num_gdb(sb, grp) +
4126                         (has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
4127                         sbi->s_itb_per_group + 2);
4128
4129         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4130                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
4131         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4132         for (i = 0; i < ngroups; i++) {
4133                 gdp = ext4_get_group_desc(sb, i, NULL);
4134                 b = ext4_block_bitmap(sb, gdp);
4135                 if (b >= first_block && b <= last_block) {
4136                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4137                         count++;
4138                 }
4139                 b = ext4_inode_bitmap(sb, gdp);
4140                 if (b >= first_block && b <= last_block) {
4141                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4142                         count++;
4143                 }
4144                 b = ext4_inode_table(sb, gdp);
4145                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4146                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4147                                 int c = EXT4_B2C(sbi, b - first_block);
4148                                 ext4_set_bit(c, buf);
4149                                 count++;
4150                         }
4151                 if (i != grp)
4152                         continue;
4153                 s = 0;
4154                 if (ext4_bg_has_super(sb, grp)) {
4155                         ext4_set_bit(s++, buf);
4156                         count++;
4157                 }
4158                 j = ext4_bg_num_gdb(sb, grp);
4159                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4160                         ext4_error(sb, "Invalid number of block group "
4161                                    "descriptor blocks: %d", j);
4162                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4163                 }
4164                 count += j;
4165                 for (; j > 0; j--)
4166                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4167         }
4168         if (!count)
4169                 return 0;
4170         return EXT4_CLUSTERS_PER_GROUP(sb) -
4171                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4172 }
4173
4174 /*
4175  * Compute the overhead and stash it in sbi->s_overhead
4176  */
4177 int ext4_calculate_overhead(struct super_block *sb)
4178 {
4179         struct ext4_sb_info *sbi = EXT4_SB(sb);
4180         struct ext4_super_block *es = sbi->s_es;
4181         struct inode *j_inode;
4182         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4183         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4184         ext4_fsblk_t overhead = 0;
4185         char *buf = (char *) get_zeroed_page(GFP_NOFS);
4186
4187         if (!buf)
4188                 return -ENOMEM;
4189
4190         /*
4191          * Compute the overhead (FS structures).  This is constant
4192          * for a given filesystem unless the number of block groups
4193          * changes so we cache the previous value until it does.
4194          */
4195
4196         /*
4197          * All of the blocks before first_data_block are overhead
4198          */
4199         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4200
4201         /*
4202          * Add the overhead found in each block group
4203          */
4204         for (i = 0; i < ngroups; i++) {
4205                 int blks;
4206
4207                 blks = count_overhead(sb, i, buf);
4208                 overhead += blks;
4209                 if (blks)
4210                         memset(buf, 0, PAGE_SIZE);
4211                 cond_resched();
4212         }
4213
4214         /*
4215          * Add the internal journal blocks whether the journal has been
4216          * loaded or not
4217          */
4218         if (sbi->s_journal && !sbi->s_journal_bdev_file)
4219                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4220         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4221                 /* j_inum for internal journal is non-zero */
4222                 j_inode = ext4_get_journal_inode(sb, j_inum);
4223                 if (!IS_ERR(j_inode)) {
4224                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4225                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
4226                         iput(j_inode);
4227                 } else {
4228                         ext4_msg(sb, KERN_ERR, "can't get journal size");
4229                 }
4230         }
4231         sbi->s_overhead = overhead;
4232         smp_wmb();
4233         free_page((unsigned long) buf);
4234         return 0;
4235 }
4236
4237 static void ext4_set_resv_clusters(struct super_block *sb)
4238 {
4239         ext4_fsblk_t resv_clusters;
4240         struct ext4_sb_info *sbi = EXT4_SB(sb);
4241
4242         /*
4243          * There's no need to reserve anything when we aren't using extents.
4244          * The space estimates are exact, there are no unwritten extents,
4245          * hole punching doesn't need new metadata... This is needed especially
4246          * to keep ext2/3 backward compatibility.
4247          */
4248         if (!ext4_has_feature_extents(sb))
4249                 return;
4250         /*
4251          * By default we reserve 2% or 4096 clusters, whichever is smaller.
4252          * This should cover the situations where we can not afford to run
4253          * out of space like for example punch hole, or converting
4254          * unwritten extents in delalloc path. In most cases such
4255          * allocation would require 1, or 2 blocks, higher numbers are
4256          * very rare.
4257          */
4258         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4259                          sbi->s_cluster_bits);
4260
4261         do_div(resv_clusters, 50);
4262         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4263
4264         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4265 }
4266
4267 static const char *ext4_quota_mode(struct super_block *sb)
4268 {
4269 #ifdef CONFIG_QUOTA
4270         if (!ext4_quota_capable(sb))
4271                 return "none";
4272
4273         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4274                 return "journalled";
4275         else
4276                 return "writeback";
4277 #else
4278         return "disabled";
4279 #endif
4280 }
4281
4282 static void ext4_setup_csum_trigger(struct super_block *sb,
4283                                     enum ext4_journal_trigger_type type,
4284                                     void (*trigger)(
4285                                         struct jbd2_buffer_trigger_type *type,
4286                                         struct buffer_head *bh,
4287                                         void *mapped_data,
4288                                         size_t size))
4289 {
4290         struct ext4_sb_info *sbi = EXT4_SB(sb);
4291
4292         sbi->s_journal_triggers[type].sb = sb;
4293         sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4294 }
4295
4296 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4297 {
4298         if (!sbi)
4299                 return;
4300
4301         kfree(sbi->s_blockgroup_lock);
4302         fs_put_dax(sbi->s_daxdev, NULL);
4303         kfree(sbi);
4304 }
4305
4306 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4307 {
4308         struct ext4_sb_info *sbi;
4309
4310         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4311         if (!sbi)
4312                 return NULL;
4313
4314         sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
4315                                            NULL, NULL);
4316
4317         sbi->s_blockgroup_lock =
4318                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4319
4320         if (!sbi->s_blockgroup_lock)
4321                 goto err_out;
4322
4323         sb->s_fs_info = sbi;
4324         sbi->s_sb = sb;
4325         return sbi;
4326 err_out:
4327         fs_put_dax(sbi->s_daxdev, NULL);
4328         kfree(sbi);
4329         return NULL;
4330 }
4331
4332 static void ext4_set_def_opts(struct super_block *sb,
4333                               struct ext4_super_block *es)
4334 {
4335         unsigned long def_mount_opts;
4336
4337         /* Set defaults before we parse the mount options */
4338         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4339         set_opt(sb, INIT_INODE_TABLE);
4340         if (def_mount_opts & EXT4_DEFM_DEBUG)
4341                 set_opt(sb, DEBUG);
4342         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4343                 set_opt(sb, GRPID);
4344         if (def_mount_opts & EXT4_DEFM_UID16)
4345                 set_opt(sb, NO_UID32);
4346         /* xattr user namespace & acls are now defaulted on */
4347         set_opt(sb, XATTR_USER);
4348 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4349         set_opt(sb, POSIX_ACL);
4350 #endif
4351         if (ext4_has_feature_fast_commit(sb))
4352                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4353         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4354         if (ext4_has_metadata_csum(sb))
4355                 set_opt(sb, JOURNAL_CHECKSUM);
4356
4357         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4358                 set_opt(sb, JOURNAL_DATA);
4359         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4360                 set_opt(sb, ORDERED_DATA);
4361         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4362                 set_opt(sb, WRITEBACK_DATA);
4363
4364         if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_PANIC)
4365                 set_opt(sb, ERRORS_PANIC);
4366         else if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_CONTINUE)
4367                 set_opt(sb, ERRORS_CONT);
4368         else
4369                 set_opt(sb, ERRORS_RO);
4370         /* block_validity enabled by default; disable with noblock_validity */
4371         set_opt(sb, BLOCK_VALIDITY);
4372         if (def_mount_opts & EXT4_DEFM_DISCARD)
4373                 set_opt(sb, DISCARD);
4374
4375         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4376                 set_opt(sb, BARRIER);
4377
4378         /*
4379          * enable delayed allocation by default
4380          * Use -o nodelalloc to turn it off
4381          */
4382         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4383             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4384                 set_opt(sb, DELALLOC);
4385
4386         if (sb->s_blocksize <= PAGE_SIZE)
4387                 set_opt(sb, DIOREAD_NOLOCK);
4388 }
4389
4390 static int ext4_handle_clustersize(struct super_block *sb)
4391 {
4392         struct ext4_sb_info *sbi = EXT4_SB(sb);
4393         struct ext4_super_block *es = sbi->s_es;
4394         int clustersize;
4395
4396         /* Handle clustersize */
4397         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4398         if (ext4_has_feature_bigalloc(sb)) {
4399                 if (clustersize < sb->s_blocksize) {
4400                         ext4_msg(sb, KERN_ERR,
4401                                  "cluster size (%d) smaller than "
4402                                  "block size (%lu)", clustersize, sb->s_blocksize);
4403                         return -EINVAL;
4404                 }
4405                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4406                         le32_to_cpu(es->s_log_block_size);
4407         } else {
4408                 if (clustersize != sb->s_blocksize) {
4409                         ext4_msg(sb, KERN_ERR,
4410                                  "fragment/cluster size (%d) != "
4411                                  "block size (%lu)", clustersize, sb->s_blocksize);
4412                         return -EINVAL;
4413                 }
4414                 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
4415                         ext4_msg(sb, KERN_ERR,
4416                                  "#blocks per group too big: %lu",
4417                                  sbi->s_blocks_per_group);
4418                         return -EINVAL;
4419                 }
4420                 sbi->s_cluster_bits = 0;
4421         }
4422         sbi->s_clusters_per_group = le32_to_cpu(es->s_clusters_per_group);
4423         if (sbi->s_clusters_per_group > sb->s_blocksize * 8) {
4424                 ext4_msg(sb, KERN_ERR, "#clusters per group too big: %lu",
4425                          sbi->s_clusters_per_group);
4426                 return -EINVAL;
4427         }
4428         if (sbi->s_blocks_per_group !=
4429             (sbi->s_clusters_per_group * (clustersize / sb->s_blocksize))) {
4430                 ext4_msg(sb, KERN_ERR,
4431                          "blocks per group (%lu) and clusters per group (%lu) inconsistent",
4432                          sbi->s_blocks_per_group, sbi->s_clusters_per_group);
4433                 return -EINVAL;
4434         }
4435         sbi->s_cluster_ratio = clustersize / sb->s_blocksize;
4436
4437         /* Do we have standard group size of clustersize * 8 blocks ? */
4438         if (sbi->s_blocks_per_group == clustersize << 3)
4439                 set_opt2(sb, STD_GROUP_SIZE);
4440
4441         return 0;
4442 }
4443
4444 /*
4445  * ext4_atomic_write_init: Initializes filesystem min & max atomic write units.
4446  * @sb: super block
4447  * TODO: Later add support for bigalloc
4448  */
4449 static void ext4_atomic_write_init(struct super_block *sb)
4450 {
4451         struct ext4_sb_info *sbi = EXT4_SB(sb);
4452         struct block_device *bdev = sb->s_bdev;
4453
4454         if (!bdev_can_atomic_write(bdev))
4455                 return;
4456
4457         if (!ext4_has_feature_extents(sb))
4458                 return;
4459
4460         sbi->s_awu_min = max(sb->s_blocksize,
4461                               bdev_atomic_write_unit_min_bytes(bdev));
4462         sbi->s_awu_max = min(sb->s_blocksize,
4463                               bdev_atomic_write_unit_max_bytes(bdev));
4464         if (sbi->s_awu_min && sbi->s_awu_max &&
4465             sbi->s_awu_min <= sbi->s_awu_max) {
4466                 ext4_msg(sb, KERN_NOTICE, "Supports (experimental) DIO atomic writes awu_min: %u, awu_max: %u",
4467                          sbi->s_awu_min, sbi->s_awu_max);
4468         } else {
4469                 sbi->s_awu_min = 0;
4470                 sbi->s_awu_max = 0;
4471         }
4472 }
4473
4474 static void ext4_fast_commit_init(struct super_block *sb)
4475 {
4476         struct ext4_sb_info *sbi = EXT4_SB(sb);
4477
4478         /* Initialize fast commit stuff */
4479         atomic_set(&sbi->s_fc_subtid, 0);
4480         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4481         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4482         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4483         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4484         sbi->s_fc_bytes = 0;
4485         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4486         sbi->s_fc_ineligible_tid = 0;
4487         spin_lock_init(&sbi->s_fc_lock);
4488         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4489         sbi->s_fc_replay_state.fc_regions = NULL;
4490         sbi->s_fc_replay_state.fc_regions_size = 0;
4491         sbi->s_fc_replay_state.fc_regions_used = 0;
4492         sbi->s_fc_replay_state.fc_regions_valid = 0;
4493         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4494         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4495         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4496 }
4497
4498 static int ext4_inode_info_init(struct super_block *sb,
4499                                 struct ext4_super_block *es)
4500 {
4501         struct ext4_sb_info *sbi = EXT4_SB(sb);
4502
4503         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4504                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4505                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4506         } else {
4507                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4508                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4509                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4510                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4511                                  sbi->s_first_ino);
4512                         return -EINVAL;
4513                 }
4514                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4515                     (!is_power_of_2(sbi->s_inode_size)) ||
4516                     (sbi->s_inode_size > sb->s_blocksize)) {
4517                         ext4_msg(sb, KERN_ERR,
4518                                "unsupported inode size: %d",
4519                                sbi->s_inode_size);
4520                         ext4_msg(sb, KERN_ERR, "blocksize: %lu", sb->s_blocksize);
4521                         return -EINVAL;
4522                 }
4523                 /*
4524                  * i_atime_extra is the last extra field available for
4525                  * [acm]times in struct ext4_inode. Checking for that
4526                  * field should suffice to ensure we have extra space
4527                  * for all three.
4528                  */
4529                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4530                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4531                         sb->s_time_gran = 1;
4532                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4533                 } else {
4534                         sb->s_time_gran = NSEC_PER_SEC;
4535                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4536                 }
4537                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4538         }
4539
4540         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4541                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4542                         EXT4_GOOD_OLD_INODE_SIZE;
4543                 if (ext4_has_feature_extra_isize(sb)) {
4544                         unsigned v, max = (sbi->s_inode_size -
4545                                            EXT4_GOOD_OLD_INODE_SIZE);
4546
4547                         v = le16_to_cpu(es->s_want_extra_isize);
4548                         if (v > max) {
4549                                 ext4_msg(sb, KERN_ERR,
4550                                          "bad s_want_extra_isize: %d", v);
4551                                 return -EINVAL;
4552                         }
4553                         if (sbi->s_want_extra_isize < v)
4554                                 sbi->s_want_extra_isize = v;
4555
4556                         v = le16_to_cpu(es->s_min_extra_isize);
4557                         if (v > max) {
4558                                 ext4_msg(sb, KERN_ERR,
4559                                          "bad s_min_extra_isize: %d", v);
4560                                 return -EINVAL;
4561                         }
4562                         if (sbi->s_want_extra_isize < v)
4563                                 sbi->s_want_extra_isize = v;
4564                 }
4565         }
4566
4567         return 0;
4568 }
4569
4570 #if IS_ENABLED(CONFIG_UNICODE)
4571 static int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4572 {
4573         const struct ext4_sb_encodings *encoding_info;
4574         struct unicode_map *encoding;
4575         __u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4576
4577         if (!ext4_has_feature_casefold(sb) || sb->s_encoding)
4578                 return 0;
4579
4580         encoding_info = ext4_sb_read_encoding(es);
4581         if (!encoding_info) {
4582                 ext4_msg(sb, KERN_ERR,
4583                         "Encoding requested by superblock is unknown");
4584                 return -EINVAL;
4585         }
4586
4587         encoding = utf8_load(encoding_info->version);
4588         if (IS_ERR(encoding)) {
4589                 ext4_msg(sb, KERN_ERR,
4590                         "can't mount with superblock charset: %s-%u.%u.%u "
4591                         "not supported by the kernel. flags: 0x%x.",
4592                         encoding_info->name,
4593                         unicode_major(encoding_info->version),
4594                         unicode_minor(encoding_info->version),
4595                         unicode_rev(encoding_info->version),
4596                         encoding_flags);
4597                 return -EINVAL;
4598         }
4599         ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4600                 "%s-%u.%u.%u with flags 0x%hx", encoding_info->name,
4601                 unicode_major(encoding_info->version),
4602                 unicode_minor(encoding_info->version),
4603                 unicode_rev(encoding_info->version),
4604                 encoding_flags);
4605
4606         sb->s_encoding = encoding;
4607         sb->s_encoding_flags = encoding_flags;
4608
4609         return 0;
4610 }
4611 #else
4612 static inline int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4613 {
4614         return 0;
4615 }
4616 #endif
4617
4618 static int ext4_init_metadata_csum(struct super_block *sb, struct ext4_super_block *es)
4619 {
4620         struct ext4_sb_info *sbi = EXT4_SB(sb);
4621
4622         /* Warn if metadata_csum and gdt_csum are both set. */
4623         if (ext4_has_feature_metadata_csum(sb) &&
4624             ext4_has_feature_gdt_csum(sb))
4625                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4626                              "redundant flags; please run fsck.");
4627
4628         /* Check for a known checksum algorithm */
4629         if (!ext4_verify_csum_type(sb, es)) {
4630                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4631                          "unknown checksum algorithm.");
4632                 return -EINVAL;
4633         }
4634         ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4635                                 ext4_orphan_file_block_trigger);
4636
4637         /* Load the checksum driver */
4638         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4639         if (IS_ERR(sbi->s_chksum_driver)) {
4640                 int ret = PTR_ERR(sbi->s_chksum_driver);
4641                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4642                 sbi->s_chksum_driver = NULL;
4643                 return ret;
4644         }
4645
4646         /* Check superblock checksum */
4647         if (!ext4_superblock_csum_verify(sb, es)) {
4648                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4649                          "invalid superblock checksum.  Run e2fsck?");
4650                 return -EFSBADCRC;
4651         }
4652
4653         /* Precompute checksum seed for all metadata */
4654         if (ext4_has_feature_csum_seed(sb))
4655                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4656         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4657                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4658                                                sizeof(es->s_uuid));
4659         return 0;
4660 }
4661
4662 static int ext4_check_feature_compatibility(struct super_block *sb,
4663                                             struct ext4_super_block *es,
4664                                             int silent)
4665 {
4666         struct ext4_sb_info *sbi = EXT4_SB(sb);
4667
4668         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4669             (ext4_has_compat_features(sb) ||
4670              ext4_has_ro_compat_features(sb) ||
4671              ext4_has_incompat_features(sb)))
4672                 ext4_msg(sb, KERN_WARNING,
4673                        "feature flags set on rev 0 fs, "
4674                        "running e2fsck is recommended");
4675
4676         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4677                 set_opt2(sb, HURD_COMPAT);
4678                 if (ext4_has_feature_64bit(sb)) {
4679                         ext4_msg(sb, KERN_ERR,
4680                                  "The Hurd can't support 64-bit file systems");
4681                         return -EINVAL;
4682                 }
4683
4684                 /*
4685                  * ea_inode feature uses l_i_version field which is not
4686                  * available in HURD_COMPAT mode.
4687                  */
4688                 if (ext4_has_feature_ea_inode(sb)) {
4689                         ext4_msg(sb, KERN_ERR,
4690                                  "ea_inode feature is not supported for Hurd");
4691                         return -EINVAL;
4692                 }
4693         }
4694
4695         if (IS_EXT2_SB(sb)) {
4696                 if (ext2_feature_set_ok(sb))
4697                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4698                                  "using the ext4 subsystem");
4699                 else {
4700                         /*
4701                          * If we're probing be silent, if this looks like
4702                          * it's actually an ext[34] filesystem.
4703                          */
4704                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4705                                 return -EINVAL;
4706                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4707                                  "to feature incompatibilities");
4708                         return -EINVAL;
4709                 }
4710         }
4711
4712         if (IS_EXT3_SB(sb)) {
4713                 if (ext3_feature_set_ok(sb))
4714                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4715                                  "using the ext4 subsystem");
4716                 else {
4717                         /*
4718                          * If we're probing be silent, if this looks like
4719                          * it's actually an ext4 filesystem.
4720                          */
4721                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4722                                 return -EINVAL;
4723                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4724                                  "to feature incompatibilities");
4725                         return -EINVAL;
4726                 }
4727         }
4728
4729         /*
4730          * Check feature flags regardless of the revision level, since we
4731          * previously didn't change the revision level when setting the flags,
4732          * so there is a chance incompat flags are set on a rev 0 filesystem.
4733          */
4734         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4735                 return -EINVAL;
4736
4737         if (sbi->s_daxdev) {
4738                 if (sb->s_blocksize == PAGE_SIZE)
4739                         set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4740                 else
4741                         ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
4742         }
4743
4744         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4745                 if (ext4_has_feature_inline_data(sb)) {
4746                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4747                                         " that may contain inline data");
4748                         return -EINVAL;
4749                 }
4750                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4751                         ext4_msg(sb, KERN_ERR,
4752                                 "DAX unsupported by block device.");
4753                         return -EINVAL;
4754                 }
4755         }
4756
4757         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4758                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4759                          es->s_encryption_level);
4760                 return -EINVAL;
4761         }
4762
4763         return 0;
4764 }
4765
4766 static int ext4_check_geometry(struct super_block *sb,
4767                                struct ext4_super_block *es)
4768 {
4769         struct ext4_sb_info *sbi = EXT4_SB(sb);
4770         __u64 blocks_count;
4771         int err;
4772
4773         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (sb->s_blocksize / 4)) {
4774                 ext4_msg(sb, KERN_ERR,
4775                          "Number of reserved GDT blocks insanely large: %d",
4776                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4777                 return -EINVAL;
4778         }
4779         /*
4780          * Test whether we have more sectors than will fit in sector_t,
4781          * and whether the max offset is addressable by the page cache.
4782          */
4783         err = generic_check_addressable(sb->s_blocksize_bits,
4784                                         ext4_blocks_count(es));
4785         if (err) {
4786                 ext4_msg(sb, KERN_ERR, "filesystem"
4787                          " too large to mount safely on this system");
4788                 return err;
4789         }
4790
4791         /* check blocks count against device size */
4792         blocks_count = sb_bdev_nr_blocks(sb);
4793         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4794                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4795                        "exceeds size of device (%llu blocks)",
4796                        ext4_blocks_count(es), blocks_count);
4797                 return -EINVAL;
4798         }
4799
4800         /*
4801          * It makes no sense for the first data block to be beyond the end
4802          * of the filesystem.
4803          */
4804         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4805                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4806                          "block %u is beyond end of filesystem (%llu)",
4807                          le32_to_cpu(es->s_first_data_block),
4808                          ext4_blocks_count(es));
4809                 return -EINVAL;
4810         }
4811         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4812             (sbi->s_cluster_ratio == 1)) {
4813                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4814                          "block is 0 with a 1k block and cluster size");
4815                 return -EINVAL;
4816         }
4817
4818         blocks_count = (ext4_blocks_count(es) -
4819                         le32_to_cpu(es->s_first_data_block) +
4820                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4821         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4822         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4823                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4824                        "(block count %llu, first data block %u, "
4825                        "blocks per group %lu)", blocks_count,
4826                        ext4_blocks_count(es),
4827                        le32_to_cpu(es->s_first_data_block),
4828                        EXT4_BLOCKS_PER_GROUP(sb));
4829                 return -EINVAL;
4830         }
4831         sbi->s_groups_count = blocks_count;
4832         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4833                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4834         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4835             le32_to_cpu(es->s_inodes_count)) {
4836                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4837                          le32_to_cpu(es->s_inodes_count),
4838                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4839                 return -EINVAL;
4840         }
4841
4842         return 0;
4843 }
4844
4845 static int ext4_group_desc_init(struct super_block *sb,
4846                                 struct ext4_super_block *es,
4847                                 ext4_fsblk_t logical_sb_block,
4848                                 ext4_group_t *first_not_zeroed)
4849 {
4850         struct ext4_sb_info *sbi = EXT4_SB(sb);
4851         unsigned int db_count;
4852         ext4_fsblk_t block;
4853         int i;
4854
4855         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4856                    EXT4_DESC_PER_BLOCK(sb);
4857         if (ext4_has_feature_meta_bg(sb)) {
4858                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4859                         ext4_msg(sb, KERN_WARNING,
4860                                  "first meta block group too large: %u "
4861                                  "(group descriptor block count %u)",
4862                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4863                         return -EINVAL;
4864                 }
4865         }
4866         rcu_assign_pointer(sbi->s_group_desc,
4867                            kvmalloc_array(db_count,
4868                                           sizeof(struct buffer_head *),
4869                                           GFP_KERNEL));
4870         if (sbi->s_group_desc == NULL) {
4871                 ext4_msg(sb, KERN_ERR, "not enough memory");
4872                 return -ENOMEM;
4873         }
4874
4875         bgl_lock_init(sbi->s_blockgroup_lock);
4876
4877         /* Pre-read the descriptors into the buffer cache */
4878         for (i = 0; i < db_count; i++) {
4879                 block = descriptor_loc(sb, logical_sb_block, i);
4880                 ext4_sb_breadahead_unmovable(sb, block);
4881         }
4882
4883         for (i = 0; i < db_count; i++) {
4884                 struct buffer_head *bh;
4885
4886                 block = descriptor_loc(sb, logical_sb_block, i);
4887                 bh = ext4_sb_bread_unmovable(sb, block);
4888                 if (IS_ERR(bh)) {
4889                         ext4_msg(sb, KERN_ERR,
4890                                "can't read group descriptor %d", i);
4891                         sbi->s_gdb_count = i;
4892                         return PTR_ERR(bh);
4893                 }
4894                 rcu_read_lock();
4895                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4896                 rcu_read_unlock();
4897         }
4898         sbi->s_gdb_count = db_count;
4899         if (!ext4_check_descriptors(sb, logical_sb_block, first_not_zeroed)) {
4900                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4901                 return -EFSCORRUPTED;
4902         }
4903
4904         return 0;
4905 }
4906
4907 static int ext4_load_and_init_journal(struct super_block *sb,
4908                                       struct ext4_super_block *es,
4909                                       struct ext4_fs_context *ctx)
4910 {
4911         struct ext4_sb_info *sbi = EXT4_SB(sb);
4912         int err;
4913
4914         err = ext4_load_journal(sb, es, ctx->journal_devnum);
4915         if (err)
4916                 return err;
4917
4918         if (ext4_has_feature_64bit(sb) &&
4919             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4920                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4921                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4922                 goto out;
4923         }
4924
4925         if (!set_journal_csum_feature_set(sb)) {
4926                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4927                          "feature set");
4928                 goto out;
4929         }
4930
4931         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4932                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4933                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4934                 ext4_msg(sb, KERN_ERR,
4935                         "Failed to set fast commit journal feature");
4936                 goto out;
4937         }
4938
4939         /* We have now updated the journal if required, so we can
4940          * validate the data journaling mode. */
4941         switch (test_opt(sb, DATA_FLAGS)) {
4942         case 0:
4943                 /* No mode set, assume a default based on the journal
4944                  * capabilities: ORDERED_DATA if the journal can
4945                  * cope, else JOURNAL_DATA
4946                  */
4947                 if (jbd2_journal_check_available_features
4948                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4949                         set_opt(sb, ORDERED_DATA);
4950                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4951                 } else {
4952                         set_opt(sb, JOURNAL_DATA);
4953                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4954                 }
4955                 break;
4956
4957         case EXT4_MOUNT_ORDERED_DATA:
4958         case EXT4_MOUNT_WRITEBACK_DATA:
4959                 if (!jbd2_journal_check_available_features
4960                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4961                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4962                                "requested data journaling mode");
4963                         goto out;
4964                 }
4965                 break;
4966         default:
4967                 break;
4968         }
4969
4970         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4971             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4972                 ext4_msg(sb, KERN_ERR, "can't mount with "
4973                         "journal_async_commit in data=ordered mode");
4974                 goto out;
4975         }
4976
4977         set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
4978
4979         sbi->s_journal->j_submit_inode_data_buffers =
4980                 ext4_journal_submit_inode_data_buffers;
4981         sbi->s_journal->j_finish_inode_data_buffers =
4982                 ext4_journal_finish_inode_data_buffers;
4983
4984         return 0;
4985
4986 out:
4987         /* flush s_sb_upd_work before destroying the journal. */
4988         flush_work(&sbi->s_sb_upd_work);
4989         jbd2_journal_destroy(sbi->s_journal);
4990         sbi->s_journal = NULL;
4991         return -EINVAL;
4992 }
4993
4994 static int ext4_check_journal_data_mode(struct super_block *sb)
4995 {
4996         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4997                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with "
4998                             "data=journal disables delayed allocation, "
4999                             "dioread_nolock, O_DIRECT and fast_commit support!\n");
5000                 /* can't mount with both data=journal and dioread_nolock. */
5001                 clear_opt(sb, DIOREAD_NOLOCK);
5002                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
5003                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5004                         ext4_msg(sb, KERN_ERR, "can't mount with "
5005                                  "both data=journal and delalloc");
5006                         return -EINVAL;
5007                 }
5008                 if (test_opt(sb, DAX_ALWAYS)) {
5009                         ext4_msg(sb, KERN_ERR, "can't mount with "
5010                                  "both data=journal and dax");
5011                         return -EINVAL;
5012                 }
5013                 if (ext4_has_feature_encrypt(sb)) {
5014                         ext4_msg(sb, KERN_WARNING,
5015                                  "encrypted files will use data=ordered "
5016                                  "instead of data journaling mode");
5017                 }
5018                 if (test_opt(sb, DELALLOC))
5019                         clear_opt(sb, DELALLOC);
5020         } else {
5021                 sb->s_iflags |= SB_I_CGROUPWB;
5022         }
5023
5024         return 0;
5025 }
5026
5027 static int ext4_load_super(struct super_block *sb, ext4_fsblk_t *lsb,
5028                            int silent)
5029 {
5030         struct ext4_sb_info *sbi = EXT4_SB(sb);
5031         struct ext4_super_block *es;
5032         ext4_fsblk_t logical_sb_block;
5033         unsigned long offset = 0;
5034         struct buffer_head *bh;
5035         int ret = -EINVAL;
5036         int blocksize;
5037
5038         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
5039         if (!blocksize) {
5040                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
5041                 return -EINVAL;
5042         }
5043
5044         /*
5045          * The ext4 superblock will not be buffer aligned for other than 1kB
5046          * block sizes.  We need to calculate the offset from buffer start.
5047          */
5048         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
5049                 logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5050                 offset = do_div(logical_sb_block, blocksize);
5051         } else {
5052                 logical_sb_block = sbi->s_sb_block;
5053         }
5054
5055         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5056         if (IS_ERR(bh)) {
5057                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
5058                 return PTR_ERR(bh);
5059         }
5060         /*
5061          * Note: s_es must be initialized as soon as possible because
5062          *       some ext4 macro-instructions depend on its value
5063          */
5064         es = (struct ext4_super_block *) (bh->b_data + offset);
5065         sbi->s_es = es;
5066         sb->s_magic = le16_to_cpu(es->s_magic);
5067         if (sb->s_magic != EXT4_SUPER_MAGIC) {
5068                 if (!silent)
5069                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5070                 goto out;
5071         }
5072
5073         if (le32_to_cpu(es->s_log_block_size) >
5074             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5075                 ext4_msg(sb, KERN_ERR,
5076                          "Invalid log block size: %u",
5077                          le32_to_cpu(es->s_log_block_size));
5078                 goto out;
5079         }
5080         if (le32_to_cpu(es->s_log_cluster_size) >
5081             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5082                 ext4_msg(sb, KERN_ERR,
5083                          "Invalid log cluster size: %u",
5084                          le32_to_cpu(es->s_log_cluster_size));
5085                 goto out;
5086         }
5087
5088         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
5089
5090         /*
5091          * If the default block size is not the same as the real block size,
5092          * we need to reload it.
5093          */
5094         if (sb->s_blocksize == blocksize) {
5095                 *lsb = logical_sb_block;
5096                 sbi->s_sbh = bh;
5097                 return 0;
5098         }
5099
5100         /*
5101          * bh must be released before kill_bdev(), otherwise
5102          * it won't be freed and its page also. kill_bdev()
5103          * is called by sb_set_blocksize().
5104          */
5105         brelse(bh);
5106         /* Validate the filesystem blocksize */
5107         if (!sb_set_blocksize(sb, blocksize)) {
5108                 ext4_msg(sb, KERN_ERR, "bad block size %d",
5109                                 blocksize);
5110                 bh = NULL;
5111                 goto out;
5112         }
5113
5114         logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5115         offset = do_div(logical_sb_block, blocksize);
5116         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5117         if (IS_ERR(bh)) {
5118                 ext4_msg(sb, KERN_ERR, "Can't read superblock on 2nd try");
5119                 ret = PTR_ERR(bh);
5120                 bh = NULL;
5121                 goto out;
5122         }
5123         es = (struct ext4_super_block *)(bh->b_data + offset);
5124         sbi->s_es = es;
5125         if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
5126                 ext4_msg(sb, KERN_ERR, "Magic mismatch, very weird!");
5127                 goto out;
5128         }
5129         *lsb = logical_sb_block;
5130         sbi->s_sbh = bh;
5131         return 0;
5132 out:
5133         brelse(bh);
5134         return ret;
5135 }
5136
5137 static int ext4_hash_info_init(struct super_block *sb)
5138 {
5139         struct ext4_sb_info *sbi = EXT4_SB(sb);
5140         struct ext4_super_block *es = sbi->s_es;
5141         unsigned int i;
5142
5143         sbi->s_def_hash_version = es->s_def_hash_version;
5144
5145         if (sbi->s_def_hash_version > DX_HASH_LAST) {
5146                 ext4_msg(sb, KERN_ERR,
5147                          "Invalid default hash set in the superblock");
5148                 return -EINVAL;
5149         } else if (sbi->s_def_hash_version == DX_HASH_SIPHASH) {
5150                 ext4_msg(sb, KERN_ERR,
5151                          "SIPHASH is not a valid default hash value");
5152                 return -EINVAL;
5153         }
5154
5155         for (i = 0; i < 4; i++)
5156                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
5157
5158         if (ext4_has_feature_dir_index(sb)) {
5159                 i = le32_to_cpu(es->s_flags);
5160                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
5161                         sbi->s_hash_unsigned = 3;
5162                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
5163 #ifdef __CHAR_UNSIGNED__
5164                         if (!sb_rdonly(sb))
5165                                 es->s_flags |=
5166                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
5167                         sbi->s_hash_unsigned = 3;
5168 #else
5169                         if (!sb_rdonly(sb))
5170                                 es->s_flags |=
5171                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
5172 #endif
5173                 }
5174         }
5175         return 0;
5176 }
5177
5178 static int ext4_block_group_meta_init(struct super_block *sb, int silent)
5179 {
5180         struct ext4_sb_info *sbi = EXT4_SB(sb);
5181         struct ext4_super_block *es = sbi->s_es;
5182         int has_huge_files;
5183
5184         has_huge_files = ext4_has_feature_huge_file(sb);
5185         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
5186                                                       has_huge_files);
5187         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
5188
5189         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
5190         if (ext4_has_feature_64bit(sb)) {
5191                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
5192                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
5193                     !is_power_of_2(sbi->s_desc_size)) {
5194                         ext4_msg(sb, KERN_ERR,
5195                                "unsupported descriptor size %lu",
5196                                sbi->s_desc_size);
5197                         return -EINVAL;
5198                 }
5199         } else
5200                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
5201
5202         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
5203         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
5204
5205         sbi->s_inodes_per_block = sb->s_blocksize / EXT4_INODE_SIZE(sb);
5206         if (sbi->s_inodes_per_block == 0 || sbi->s_blocks_per_group == 0) {
5207                 if (!silent)
5208                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5209                 return -EINVAL;
5210         }
5211         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
5212             sbi->s_inodes_per_group > sb->s_blocksize * 8) {
5213                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
5214                          sbi->s_inodes_per_group);
5215                 return -EINVAL;
5216         }
5217         sbi->s_itb_per_group = sbi->s_inodes_per_group /
5218                                         sbi->s_inodes_per_block;
5219         sbi->s_desc_per_block = sb->s_blocksize / EXT4_DESC_SIZE(sb);
5220         sbi->s_mount_state = le16_to_cpu(es->s_state) & ~EXT4_FC_REPLAY;
5221         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
5222         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
5223
5224         return 0;
5225 }
5226
5227 /*
5228  * It's hard to get stripe aligned blocks if stripe is not aligned with
5229  * cluster, just disable stripe and alert user to simplify code and avoid
5230  * stripe aligned allocation which will rarely succeed.
5231  */
5232 static bool ext4_is_stripe_incompatible(struct super_block *sb, unsigned long stripe)
5233 {
5234         struct ext4_sb_info *sbi = EXT4_SB(sb);
5235         return (stripe > 0 && sbi->s_cluster_ratio > 1 &&
5236                 stripe % sbi->s_cluster_ratio != 0);
5237 }
5238
5239 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
5240 {
5241         struct ext4_super_block *es = NULL;
5242         struct ext4_sb_info *sbi = EXT4_SB(sb);
5243         ext4_fsblk_t logical_sb_block;
5244         struct inode *root;
5245         int needs_recovery;
5246         int err;
5247         ext4_group_t first_not_zeroed;
5248         struct ext4_fs_context *ctx = fc->fs_private;
5249         int silent = fc->sb_flags & SB_SILENT;
5250
5251         /* Set defaults for the variables that will be set during parsing */
5252         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO))
5253                 ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5254
5255         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
5256         sbi->s_sectors_written_start =
5257                 part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
5258
5259         err = ext4_load_super(sb, &logical_sb_block, silent);
5260         if (err)
5261                 goto out_fail;
5262
5263         es = sbi->s_es;
5264         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
5265
5266         err = ext4_init_metadata_csum(sb, es);
5267         if (err)
5268                 goto failed_mount;
5269
5270         ext4_set_def_opts(sb, es);
5271
5272         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
5273         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
5274         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
5275         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
5276         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
5277
5278         /*
5279          * set default s_li_wait_mult for lazyinit, for the case there is
5280          * no mount option specified.
5281          */
5282         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
5283
5284         err = ext4_inode_info_init(sb, es);
5285         if (err)
5286                 goto failed_mount;
5287
5288         err = parse_apply_sb_mount_options(sb, ctx);
5289         if (err < 0)
5290                 goto failed_mount;
5291
5292         sbi->s_def_mount_opt = sbi->s_mount_opt;
5293         sbi->s_def_mount_opt2 = sbi->s_mount_opt2;
5294
5295         err = ext4_check_opt_consistency(fc, sb);
5296         if (err < 0)
5297                 goto failed_mount;
5298
5299         ext4_apply_options(fc, sb);
5300
5301         err = ext4_encoding_init(sb, es);
5302         if (err)
5303                 goto failed_mount;
5304
5305         err = ext4_check_journal_data_mode(sb);
5306         if (err)
5307                 goto failed_mount;
5308
5309         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5310                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5311
5312         /* i_version is always enabled now */
5313         sb->s_flags |= SB_I_VERSION;
5314
5315         err = ext4_check_feature_compatibility(sb, es, silent);
5316         if (err)
5317                 goto failed_mount;
5318
5319         err = ext4_block_group_meta_init(sb, silent);
5320         if (err)
5321                 goto failed_mount;
5322
5323         err = ext4_hash_info_init(sb);
5324         if (err)
5325                 goto failed_mount;
5326
5327         err = ext4_handle_clustersize(sb);
5328         if (err)
5329                 goto failed_mount;
5330
5331         err = ext4_check_geometry(sb, es);
5332         if (err)
5333                 goto failed_mount;
5334
5335         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5336         spin_lock_init(&sbi->s_error_lock);
5337         INIT_WORK(&sbi->s_sb_upd_work, update_super_work);
5338
5339         err = ext4_group_desc_init(sb, es, logical_sb_block, &first_not_zeroed);
5340         if (err)
5341                 goto failed_mount3;
5342
5343         err = ext4_es_register_shrinker(sbi);
5344         if (err)
5345                 goto failed_mount3;
5346
5347         sbi->s_stripe = ext4_get_stripe_size(sbi);
5348         if (ext4_is_stripe_incompatible(sb, sbi->s_stripe)) {
5349                 ext4_msg(sb, KERN_WARNING,
5350                          "stripe (%lu) is not aligned with cluster size (%u), "
5351                          "stripe is disabled",
5352                          sbi->s_stripe, sbi->s_cluster_ratio);
5353                 sbi->s_stripe = 0;
5354         }
5355         sbi->s_extent_max_zeroout_kb = 32;
5356
5357         /*
5358          * set up enough so that it can read an inode
5359          */
5360         sb->s_op = &ext4_sops;
5361         sb->s_export_op = &ext4_export_ops;
5362         sb->s_xattr = ext4_xattr_handlers;
5363 #ifdef CONFIG_FS_ENCRYPTION
5364         sb->s_cop = &ext4_cryptops;
5365 #endif
5366 #ifdef CONFIG_FS_VERITY
5367         sb->s_vop = &ext4_verityops;
5368 #endif
5369 #ifdef CONFIG_QUOTA
5370         sb->dq_op = &ext4_quota_operations;
5371         if (ext4_has_feature_quota(sb))
5372                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
5373         else
5374                 sb->s_qcop = &ext4_qctl_operations;
5375         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5376 #endif
5377         super_set_uuid(sb, es->s_uuid, sizeof(es->s_uuid));
5378         super_set_sysfs_name_bdev(sb);
5379
5380         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5381         mutex_init(&sbi->s_orphan_lock);
5382
5383         spin_lock_init(&sbi->s_bdev_wb_lock);
5384
5385         ext4_atomic_write_init(sb);
5386         ext4_fast_commit_init(sb);
5387
5388         sb->s_root = NULL;
5389
5390         needs_recovery = (es->s_last_orphan != 0 ||
5391                           ext4_has_feature_orphan_present(sb) ||
5392                           ext4_has_feature_journal_needs_recovery(sb));
5393
5394         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb)) {
5395                 err = ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block));
5396                 if (err)
5397                         goto failed_mount3a;
5398         }
5399
5400         err = -EINVAL;
5401         /*
5402          * The first inode we look at is the journal inode.  Don't try
5403          * root first: it may be modified in the journal!
5404          */
5405         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5406                 err = ext4_load_and_init_journal(sb, es, ctx);
5407                 if (err)
5408                         goto failed_mount3a;
5409         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5410                    ext4_has_feature_journal_needs_recovery(sb)) {
5411                 ext4_msg(sb, KERN_ERR, "required journal recovery "
5412                        "suppressed and not mounted read-only");
5413                 goto failed_mount3a;
5414         } else {
5415                 /* Nojournal mode, all journal mount options are illegal */
5416                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5417                         ext4_msg(sb, KERN_ERR, "can't mount with "
5418                                  "journal_async_commit, fs mounted w/o journal");
5419                         goto failed_mount3a;
5420                 }
5421
5422                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
5423                         ext4_msg(sb, KERN_ERR, "can't mount with "
5424                                  "journal_checksum, fs mounted w/o journal");
5425                         goto failed_mount3a;
5426                 }
5427                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
5428                         ext4_msg(sb, KERN_ERR, "can't mount with "
5429                                  "commit=%lu, fs mounted w/o journal",
5430                                  sbi->s_commit_interval / HZ);
5431                         goto failed_mount3a;
5432                 }
5433                 if (EXT4_MOUNT_DATA_FLAGS &
5434                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
5435                         ext4_msg(sb, KERN_ERR, "can't mount with "
5436                                  "data=, fs mounted w/o journal");
5437                         goto failed_mount3a;
5438                 }
5439                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5440                 clear_opt(sb, JOURNAL_CHECKSUM);
5441                 clear_opt(sb, DATA_FLAGS);
5442                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
5443                 sbi->s_journal = NULL;
5444                 needs_recovery = 0;
5445         }
5446
5447         if (!test_opt(sb, NO_MBCACHE)) {
5448                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
5449                 if (!sbi->s_ea_block_cache) {
5450                         ext4_msg(sb, KERN_ERR,
5451                                  "Failed to create ea_block_cache");
5452                         err = -EINVAL;
5453                         goto failed_mount_wq;
5454                 }
5455
5456                 if (ext4_has_feature_ea_inode(sb)) {
5457                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5458                         if (!sbi->s_ea_inode_cache) {
5459                                 ext4_msg(sb, KERN_ERR,
5460                                          "Failed to create ea_inode_cache");
5461                                 err = -EINVAL;
5462                                 goto failed_mount_wq;
5463                         }
5464                 }
5465         }
5466
5467         /*
5468          * Get the # of file system overhead blocks from the
5469          * superblock if present.
5470          */
5471         sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5472         /* ignore the precalculated value if it is ridiculous */
5473         if (sbi->s_overhead > ext4_blocks_count(es))
5474                 sbi->s_overhead = 0;
5475         /*
5476          * If the bigalloc feature is not enabled recalculating the
5477          * overhead doesn't take long, so we might as well just redo
5478          * it to make sure we are using the correct value.
5479          */
5480         if (!ext4_has_feature_bigalloc(sb))
5481                 sbi->s_overhead = 0;
5482         if (sbi->s_overhead == 0) {
5483                 err = ext4_calculate_overhead(sb);
5484                 if (err)
5485                         goto failed_mount_wq;
5486         }
5487
5488         /*
5489          * The maximum number of concurrent works can be high and
5490          * concurrency isn't really necessary.  Limit it to 1.
5491          */
5492         EXT4_SB(sb)->rsv_conversion_wq =
5493                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5494         if (!EXT4_SB(sb)->rsv_conversion_wq) {
5495                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5496                 err = -ENOMEM;
5497                 goto failed_mount4;
5498         }
5499
5500         /*
5501          * The jbd2_journal_load will have done any necessary log recovery,
5502          * so we can safely mount the rest of the filesystem now.
5503          */
5504
5505         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5506         if (IS_ERR(root)) {
5507                 ext4_msg(sb, KERN_ERR, "get root inode failed");
5508                 err = PTR_ERR(root);
5509                 root = NULL;
5510                 goto failed_mount4;
5511         }
5512         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5513                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5514                 iput(root);
5515                 err = -EFSCORRUPTED;
5516                 goto failed_mount4;
5517         }
5518
5519         generic_set_sb_d_ops(sb);
5520         sb->s_root = d_make_root(root);
5521         if (!sb->s_root) {
5522                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
5523                 err = -ENOMEM;
5524                 goto failed_mount4;
5525         }
5526
5527         err = ext4_setup_super(sb, es, sb_rdonly(sb));
5528         if (err == -EROFS) {
5529                 sb->s_flags |= SB_RDONLY;
5530         } else if (err)
5531                 goto failed_mount4a;
5532
5533         ext4_set_resv_clusters(sb);
5534
5535         if (test_opt(sb, BLOCK_VALIDITY)) {
5536                 err = ext4_setup_system_zone(sb);
5537                 if (err) {
5538                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
5539                                  "zone (%d)", err);
5540                         goto failed_mount4a;
5541                 }
5542         }
5543         ext4_fc_replay_cleanup(sb);
5544
5545         ext4_ext_init(sb);
5546
5547         /*
5548          * Enable optimize_scan if number of groups is > threshold. This can be
5549          * turned off by passing "mb_optimize_scan=0". This can also be
5550          * turned on forcefully by passing "mb_optimize_scan=1".
5551          */
5552         if (!(ctx->spec & EXT4_SPEC_mb_optimize_scan)) {
5553                 if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5554                         set_opt2(sb, MB_OPTIMIZE_SCAN);
5555                 else
5556                         clear_opt2(sb, MB_OPTIMIZE_SCAN);
5557         }
5558
5559         err = ext4_mb_init(sb);
5560         if (err) {
5561                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5562                          err);
5563                 goto failed_mount5;
5564         }
5565
5566         /*
5567          * We can only set up the journal commit callback once
5568          * mballoc is initialized
5569          */
5570         if (sbi->s_journal)
5571                 sbi->s_journal->j_commit_callback =
5572                         ext4_journal_commit_callback;
5573
5574         err = ext4_percpu_param_init(sbi);
5575         if (err)
5576                 goto failed_mount6;
5577
5578         if (ext4_has_feature_flex_bg(sb))
5579                 if (!ext4_fill_flex_info(sb)) {
5580                         ext4_msg(sb, KERN_ERR,
5581                                "unable to initialize "
5582                                "flex_bg meta info!");
5583                         err = -ENOMEM;
5584                         goto failed_mount6;
5585                 }
5586
5587         err = ext4_register_li_request(sb, first_not_zeroed);
5588         if (err)
5589                 goto failed_mount6;
5590
5591         err = ext4_init_orphan_info(sb);
5592         if (err)
5593                 goto failed_mount7;
5594 #ifdef CONFIG_QUOTA
5595         /* Enable quota usage during mount. */
5596         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5597                 err = ext4_enable_quotas(sb);
5598                 if (err)
5599                         goto failed_mount8;
5600         }
5601 #endif  /* CONFIG_QUOTA */
5602
5603         /*
5604          * Save the original bdev mapping's wb_err value which could be
5605          * used to detect the metadata async write error.
5606          */
5607         errseq_check_and_advance(&sb->s_bdev->bd_mapping->wb_err,
5608                                  &sbi->s_bdev_wb_err);
5609         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5610         ext4_orphan_cleanup(sb, es);
5611         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5612         /*
5613          * Update the checksum after updating free space/inode counters and
5614          * ext4_orphan_cleanup. Otherwise the superblock can have an incorrect
5615          * checksum in the buffer cache until it is written out and
5616          * e2fsprogs programs trying to open a file system immediately
5617          * after it is mounted can fail.
5618          */
5619         ext4_superblock_csum_set(sb);
5620         if (needs_recovery) {
5621                 ext4_msg(sb, KERN_INFO, "recovery complete");
5622                 err = ext4_mark_recovery_complete(sb, es);
5623                 if (err)
5624                         goto failed_mount9;
5625         }
5626
5627         if (test_opt(sb, DISCARD) && !bdev_max_discard_sectors(sb->s_bdev))
5628                 ext4_msg(sb, KERN_WARNING,
5629                          "mounting with \"discard\" option, but the device does not support discard");
5630
5631         if (es->s_error_count)
5632                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5633
5634         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5635         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5636         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5637         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5638         atomic_set(&sbi->s_warning_count, 0);
5639         atomic_set(&sbi->s_msg_count, 0);
5640
5641         /* Register sysfs after all initializations are complete. */
5642         err = ext4_register_sysfs(sb);
5643         if (err)
5644                 goto failed_mount9;
5645
5646         return 0;
5647
5648 failed_mount9:
5649         ext4_quotas_off(sb, EXT4_MAXQUOTAS);
5650 failed_mount8: __maybe_unused
5651         ext4_release_orphan_info(sb);
5652 failed_mount7:
5653         ext4_unregister_li_request(sb);
5654 failed_mount6:
5655         ext4_mb_release(sb);
5656         ext4_flex_groups_free(sbi);
5657         ext4_percpu_param_destroy(sbi);
5658 failed_mount5:
5659         ext4_ext_release(sb);
5660         ext4_release_system_zone(sb);
5661 failed_mount4a:
5662         dput(sb->s_root);
5663         sb->s_root = NULL;
5664 failed_mount4:
5665         ext4_msg(sb, KERN_ERR, "mount failed");
5666         if (EXT4_SB(sb)->rsv_conversion_wq)
5667                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5668 failed_mount_wq:
5669         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5670         sbi->s_ea_inode_cache = NULL;
5671
5672         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5673         sbi->s_ea_block_cache = NULL;
5674
5675         if (sbi->s_journal) {
5676                 /* flush s_sb_upd_work before journal destroy. */
5677                 flush_work(&sbi->s_sb_upd_work);
5678                 jbd2_journal_destroy(sbi->s_journal);
5679                 sbi->s_journal = NULL;
5680         }
5681 failed_mount3a:
5682         ext4_es_unregister_shrinker(sbi);
5683 failed_mount3:
5684         /* flush s_sb_upd_work before sbi destroy */
5685         flush_work(&sbi->s_sb_upd_work);
5686         ext4_stop_mmpd(sbi);
5687         del_timer_sync(&sbi->s_err_report);
5688         ext4_group_desc_free(sbi);
5689 failed_mount:
5690         if (sbi->s_chksum_driver)
5691                 crypto_free_shash(sbi->s_chksum_driver);
5692
5693 #if IS_ENABLED(CONFIG_UNICODE)
5694         utf8_unload(sb->s_encoding);
5695 #endif
5696
5697 #ifdef CONFIG_QUOTA
5698         for (unsigned int i = 0; i < EXT4_MAXQUOTAS; i++)
5699                 kfree(get_qf_name(sb, sbi, i));
5700 #endif
5701         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5702         brelse(sbi->s_sbh);
5703         if (sbi->s_journal_bdev_file) {
5704                 invalidate_bdev(file_bdev(sbi->s_journal_bdev_file));
5705                 bdev_fput(sbi->s_journal_bdev_file);
5706         }
5707 out_fail:
5708         invalidate_bdev(sb->s_bdev);
5709         sb->s_fs_info = NULL;
5710         return err;
5711 }
5712
5713 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5714 {
5715         struct ext4_fs_context *ctx = fc->fs_private;
5716         struct ext4_sb_info *sbi;
5717         const char *descr;
5718         int ret;
5719
5720         sbi = ext4_alloc_sbi(sb);
5721         if (!sbi)
5722                 return -ENOMEM;
5723
5724         fc->s_fs_info = sbi;
5725
5726         /* Cleanup superblock name */
5727         strreplace(sb->s_id, '/', '!');
5728
5729         sbi->s_sb_block = 1;    /* Default super block location */
5730         if (ctx->spec & EXT4_SPEC_s_sb_block)
5731                 sbi->s_sb_block = ctx->s_sb_block;
5732
5733         ret = __ext4_fill_super(fc, sb);
5734         if (ret < 0)
5735                 goto free_sbi;
5736
5737         if (sbi->s_journal) {
5738                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5739                         descr = " journalled data mode";
5740                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5741                         descr = " ordered data mode";
5742                 else
5743                         descr = " writeback data mode";
5744         } else
5745                 descr = "out journal";
5746
5747         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5748                 ext4_msg(sb, KERN_INFO, "mounted filesystem %pU %s with%s. "
5749                          "Quota mode: %s.", &sb->s_uuid,
5750                          sb_rdonly(sb) ? "ro" : "r/w", descr,
5751                          ext4_quota_mode(sb));
5752
5753         /* Update the s_overhead_clusters if necessary */
5754         ext4_update_overhead(sb, false);
5755         return 0;
5756
5757 free_sbi:
5758         ext4_free_sbi(sbi);
5759         fc->s_fs_info = NULL;
5760         return ret;
5761 }
5762
5763 static int ext4_get_tree(struct fs_context *fc)
5764 {
5765         return get_tree_bdev(fc, ext4_fill_super);
5766 }
5767
5768 /*
5769  * Setup any per-fs journal parameters now.  We'll do this both on
5770  * initial mount, once the journal has been initialised but before we've
5771  * done any recovery; and again on any subsequent remount.
5772  */
5773 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5774 {
5775         struct ext4_sb_info *sbi = EXT4_SB(sb);
5776
5777         journal->j_commit_interval = sbi->s_commit_interval;
5778         journal->j_min_batch_time = sbi->s_min_batch_time;
5779         journal->j_max_batch_time = sbi->s_max_batch_time;
5780         ext4_fc_init(sb, journal);
5781
5782         write_lock(&journal->j_state_lock);
5783         if (test_opt(sb, BARRIER))
5784                 journal->j_flags |= JBD2_BARRIER;
5785         else
5786                 journal->j_flags &= ~JBD2_BARRIER;
5787         if (test_opt(sb, DATA_ERR_ABORT))
5788                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5789         else
5790                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5791         /*
5792          * Always enable journal cycle record option, letting the journal
5793          * records log transactions continuously between each mount.
5794          */
5795         journal->j_flags |= JBD2_CYCLE_RECORD;
5796         write_unlock(&journal->j_state_lock);
5797 }
5798
5799 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5800                                              unsigned int journal_inum)
5801 {
5802         struct inode *journal_inode;
5803
5804         /*
5805          * Test for the existence of a valid inode on disk.  Bad things
5806          * happen if we iget() an unused inode, as the subsequent iput()
5807          * will try to delete it.
5808          */
5809         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5810         if (IS_ERR(journal_inode)) {
5811                 ext4_msg(sb, KERN_ERR, "no journal found");
5812                 return ERR_CAST(journal_inode);
5813         }
5814         if (!journal_inode->i_nlink) {
5815                 make_bad_inode(journal_inode);
5816                 iput(journal_inode);
5817                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5818                 return ERR_PTR(-EFSCORRUPTED);
5819         }
5820         if (!S_ISREG(journal_inode->i_mode) || IS_ENCRYPTED(journal_inode)) {
5821                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5822                 iput(journal_inode);
5823                 return ERR_PTR(-EFSCORRUPTED);
5824         }
5825
5826         ext4_debug("Journal inode found at %p: %lld bytes\n",
5827                   journal_inode, journal_inode->i_size);
5828         return journal_inode;
5829 }
5830
5831 static int ext4_journal_bmap(journal_t *journal, sector_t *block)
5832 {
5833         struct ext4_map_blocks map;
5834         int ret;
5835
5836         if (journal->j_inode == NULL)
5837                 return 0;
5838
5839         map.m_lblk = *block;
5840         map.m_len = 1;
5841         ret = ext4_map_blocks(NULL, journal->j_inode, &map, 0);
5842         if (ret <= 0) {
5843                 ext4_msg(journal->j_inode->i_sb, KERN_CRIT,
5844                          "journal bmap failed: block %llu ret %d\n",
5845                          *block, ret);
5846                 jbd2_journal_abort(journal, ret ? ret : -EIO);
5847                 return ret;
5848         }
5849         *block = map.m_pblk;
5850         return 0;
5851 }
5852
5853 static journal_t *ext4_open_inode_journal(struct super_block *sb,
5854                                           unsigned int journal_inum)
5855 {
5856         struct inode *journal_inode;
5857         journal_t *journal;
5858
5859         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5860         if (IS_ERR(journal_inode))
5861                 return ERR_CAST(journal_inode);
5862
5863         journal = jbd2_journal_init_inode(journal_inode);
5864         if (IS_ERR(journal)) {
5865                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5866                 iput(journal_inode);
5867                 return ERR_CAST(journal);
5868         }
5869         journal->j_private = sb;
5870         journal->j_bmap = ext4_journal_bmap;
5871         ext4_init_journal_params(sb, journal);
5872         return journal;
5873 }
5874
5875 static struct file *ext4_get_journal_blkdev(struct super_block *sb,
5876                                         dev_t j_dev, ext4_fsblk_t *j_start,
5877                                         ext4_fsblk_t *j_len)
5878 {
5879         struct buffer_head *bh;
5880         struct block_device *bdev;
5881         struct file *bdev_file;
5882         int hblock, blocksize;
5883         ext4_fsblk_t sb_block;
5884         unsigned long offset;
5885         struct ext4_super_block *es;
5886         int errno;
5887
5888         bdev_file = bdev_file_open_by_dev(j_dev,
5889                 BLK_OPEN_READ | BLK_OPEN_WRITE | BLK_OPEN_RESTRICT_WRITES,
5890                 sb, &fs_holder_ops);
5891         if (IS_ERR(bdev_file)) {
5892                 ext4_msg(sb, KERN_ERR,
5893                          "failed to open journal device unknown-block(%u,%u) %ld",
5894                          MAJOR(j_dev), MINOR(j_dev), PTR_ERR(bdev_file));
5895                 return bdev_file;
5896         }
5897
5898         bdev = file_bdev(bdev_file);
5899         blocksize = sb->s_blocksize;
5900         hblock = bdev_logical_block_size(bdev);
5901         if (blocksize < hblock) {
5902                 ext4_msg(sb, KERN_ERR,
5903                         "blocksize too small for journal device");
5904                 errno = -EINVAL;
5905                 goto out_bdev;
5906         }
5907
5908         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5909         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5910         set_blocksize(bdev_file, blocksize);
5911         bh = __bread(bdev, sb_block, blocksize);
5912         if (!bh) {
5913                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5914                        "external journal");
5915                 errno = -EINVAL;
5916                 goto out_bdev;
5917         }
5918
5919         es = (struct ext4_super_block *) (bh->b_data + offset);
5920         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5921             !(le32_to_cpu(es->s_feature_incompat) &
5922               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5923                 ext4_msg(sb, KERN_ERR, "external journal has bad superblock");
5924                 errno = -EFSCORRUPTED;
5925                 goto out_bh;
5926         }
5927
5928         if ((le32_to_cpu(es->s_feature_ro_compat) &
5929              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5930             es->s_checksum != ext4_superblock_csum(sb, es)) {
5931                 ext4_msg(sb, KERN_ERR, "external journal has corrupt superblock");
5932                 errno = -EFSCORRUPTED;
5933                 goto out_bh;
5934         }
5935
5936         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5937                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5938                 errno = -EFSCORRUPTED;
5939                 goto out_bh;
5940         }
5941
5942         *j_start = sb_block + 1;
5943         *j_len = ext4_blocks_count(es);
5944         brelse(bh);
5945         return bdev_file;
5946
5947 out_bh:
5948         brelse(bh);
5949 out_bdev:
5950         bdev_fput(bdev_file);
5951         return ERR_PTR(errno);
5952 }
5953
5954 static journal_t *ext4_open_dev_journal(struct super_block *sb,
5955                                         dev_t j_dev)
5956 {
5957         journal_t *journal;
5958         ext4_fsblk_t j_start;
5959         ext4_fsblk_t j_len;
5960         struct file *bdev_file;
5961         int errno = 0;
5962
5963         bdev_file = ext4_get_journal_blkdev(sb, j_dev, &j_start, &j_len);
5964         if (IS_ERR(bdev_file))
5965                 return ERR_CAST(bdev_file);
5966
5967         journal = jbd2_journal_init_dev(file_bdev(bdev_file), sb->s_bdev, j_start,
5968                                         j_len, sb->s_blocksize);
5969         if (IS_ERR(journal)) {
5970                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5971                 errno = PTR_ERR(journal);
5972                 goto out_bdev;
5973         }
5974         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5975                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5976                                         "user (unsupported) - %d",
5977                         be32_to_cpu(journal->j_superblock->s_nr_users));
5978                 errno = -EINVAL;
5979                 goto out_journal;
5980         }
5981         journal->j_private = sb;
5982         EXT4_SB(sb)->s_journal_bdev_file = bdev_file;
5983         ext4_init_journal_params(sb, journal);
5984         return journal;
5985
5986 out_journal:
5987         jbd2_journal_destroy(journal);
5988 out_bdev:
5989         bdev_fput(bdev_file);
5990         return ERR_PTR(errno);
5991 }
5992
5993 static int ext4_load_journal(struct super_block *sb,
5994                              struct ext4_super_block *es,
5995                              unsigned long journal_devnum)
5996 {
5997         journal_t *journal;
5998         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5999         dev_t journal_dev;
6000         int err = 0;
6001         int really_read_only;
6002         int journal_dev_ro;
6003
6004         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
6005                 return -EFSCORRUPTED;
6006
6007         if (journal_devnum &&
6008             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
6009                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
6010                         "numbers have changed");
6011                 journal_dev = new_decode_dev(journal_devnum);
6012         } else
6013                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
6014
6015         if (journal_inum && journal_dev) {
6016                 ext4_msg(sb, KERN_ERR,
6017                          "filesystem has both journal inode and journal device!");
6018                 return -EINVAL;
6019         }
6020
6021         if (journal_inum) {
6022                 journal = ext4_open_inode_journal(sb, journal_inum);
6023                 if (IS_ERR(journal))
6024                         return PTR_ERR(journal);
6025         } else {
6026                 journal = ext4_open_dev_journal(sb, journal_dev);
6027                 if (IS_ERR(journal))
6028                         return PTR_ERR(journal);
6029         }
6030
6031         journal_dev_ro = bdev_read_only(journal->j_dev);
6032         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
6033
6034         if (journal_dev_ro && !sb_rdonly(sb)) {
6035                 ext4_msg(sb, KERN_ERR,
6036                          "journal device read-only, try mounting with '-o ro'");
6037                 err = -EROFS;
6038                 goto err_out;
6039         }
6040
6041         /*
6042          * Are we loading a blank journal or performing recovery after a
6043          * crash?  For recovery, we need to check in advance whether we
6044          * can get read-write access to the device.
6045          */
6046         if (ext4_has_feature_journal_needs_recovery(sb)) {
6047                 if (sb_rdonly(sb)) {
6048                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
6049                                         "required on readonly filesystem");
6050                         if (really_read_only) {
6051                                 ext4_msg(sb, KERN_ERR, "write access "
6052                                         "unavailable, cannot proceed "
6053                                         "(try mounting with noload)");
6054                                 err = -EROFS;
6055                                 goto err_out;
6056                         }
6057                         ext4_msg(sb, KERN_INFO, "write access will "
6058                                "be enabled during recovery");
6059                 }
6060         }
6061
6062         if (!(journal->j_flags & JBD2_BARRIER))
6063                 ext4_msg(sb, KERN_INFO, "barriers disabled");
6064
6065         if (!ext4_has_feature_journal_needs_recovery(sb))
6066                 err = jbd2_journal_wipe(journal, !really_read_only);
6067         if (!err) {
6068                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
6069                 __le16 orig_state;
6070                 bool changed = false;
6071
6072                 if (save)
6073                         memcpy(save, ((char *) es) +
6074                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
6075                 err = jbd2_journal_load(journal);
6076                 if (save && memcmp(((char *) es) + EXT4_S_ERR_START,
6077                                    save, EXT4_S_ERR_LEN)) {
6078                         memcpy(((char *) es) + EXT4_S_ERR_START,
6079                                save, EXT4_S_ERR_LEN);
6080                         changed = true;
6081                 }
6082                 kfree(save);
6083                 orig_state = es->s_state;
6084                 es->s_state |= cpu_to_le16(EXT4_SB(sb)->s_mount_state &
6085                                            EXT4_ERROR_FS);
6086                 if (orig_state != es->s_state)
6087                         changed = true;
6088                 /* Write out restored error information to the superblock */
6089                 if (changed && !really_read_only) {
6090                         int err2;
6091                         err2 = ext4_commit_super(sb);
6092                         err = err ? : err2;
6093                 }
6094         }
6095
6096         if (err) {
6097                 ext4_msg(sb, KERN_ERR, "error loading journal");
6098                 goto err_out;
6099         }
6100
6101         EXT4_SB(sb)->s_journal = journal;
6102         err = ext4_clear_journal_err(sb, es);
6103         if (err) {
6104                 EXT4_SB(sb)->s_journal = NULL;
6105                 jbd2_journal_destroy(journal);
6106                 return err;
6107         }
6108
6109         if (!really_read_only && journal_devnum &&
6110             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
6111                 es->s_journal_dev = cpu_to_le32(journal_devnum);
6112                 ext4_commit_super(sb);
6113         }
6114         if (!really_read_only && journal_inum &&
6115             journal_inum != le32_to_cpu(es->s_journal_inum)) {
6116                 es->s_journal_inum = cpu_to_le32(journal_inum);
6117                 ext4_commit_super(sb);
6118         }
6119
6120         return 0;
6121
6122 err_out:
6123         jbd2_journal_destroy(journal);
6124         return err;
6125 }
6126
6127 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
6128 static void ext4_update_super(struct super_block *sb)
6129 {
6130         struct ext4_sb_info *sbi = EXT4_SB(sb);
6131         struct ext4_super_block *es = sbi->s_es;
6132         struct buffer_head *sbh = sbi->s_sbh;
6133
6134         lock_buffer(sbh);
6135         /*
6136          * If the file system is mounted read-only, don't update the
6137          * superblock write time.  This avoids updating the superblock
6138          * write time when we are mounting the root file system
6139          * read/only but we need to replay the journal; at that point,
6140          * for people who are east of GMT and who make their clock
6141          * tick in localtime for Windows bug-for-bug compatibility,
6142          * the clock is set in the future, and this will cause e2fsck
6143          * to complain and force a full file system check.
6144          */
6145         if (!sb_rdonly(sb))
6146                 ext4_update_tstamp(es, s_wtime);
6147         es->s_kbytes_written =
6148                 cpu_to_le64(sbi->s_kbytes_written +
6149                     ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
6150                       sbi->s_sectors_written_start) >> 1));
6151         if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
6152                 ext4_free_blocks_count_set(es,
6153                         EXT4_C2B(sbi, percpu_counter_sum_positive(
6154                                 &sbi->s_freeclusters_counter)));
6155         if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
6156                 es->s_free_inodes_count =
6157                         cpu_to_le32(percpu_counter_sum_positive(
6158                                 &sbi->s_freeinodes_counter));
6159         /* Copy error information to the on-disk superblock */
6160         spin_lock(&sbi->s_error_lock);
6161         if (sbi->s_add_error_count > 0) {
6162                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6163                 if (!es->s_first_error_time && !es->s_first_error_time_hi) {
6164                         __ext4_update_tstamp(&es->s_first_error_time,
6165                                              &es->s_first_error_time_hi,
6166                                              sbi->s_first_error_time);
6167                         strtomem_pad(es->s_first_error_func,
6168                                      sbi->s_first_error_func, 0);
6169                         es->s_first_error_line =
6170                                 cpu_to_le32(sbi->s_first_error_line);
6171                         es->s_first_error_ino =
6172                                 cpu_to_le32(sbi->s_first_error_ino);
6173                         es->s_first_error_block =
6174                                 cpu_to_le64(sbi->s_first_error_block);
6175                         es->s_first_error_errcode =
6176                                 ext4_errno_to_code(sbi->s_first_error_code);
6177                 }
6178                 __ext4_update_tstamp(&es->s_last_error_time,
6179                                      &es->s_last_error_time_hi,
6180                                      sbi->s_last_error_time);
6181                 strtomem_pad(es->s_last_error_func, sbi->s_last_error_func, 0);
6182                 es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
6183                 es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
6184                 es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
6185                 es->s_last_error_errcode =
6186                                 ext4_errno_to_code(sbi->s_last_error_code);
6187                 /*
6188                  * Start the daily error reporting function if it hasn't been
6189                  * started already
6190                  */
6191                 if (!es->s_error_count)
6192                         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
6193                 le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
6194                 sbi->s_add_error_count = 0;
6195         }
6196         spin_unlock(&sbi->s_error_lock);
6197
6198         ext4_superblock_csum_set(sb);
6199         unlock_buffer(sbh);
6200 }
6201
6202 static int ext4_commit_super(struct super_block *sb)
6203 {
6204         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
6205
6206         if (!sbh)
6207                 return -EINVAL;
6208
6209         ext4_update_super(sb);
6210
6211         lock_buffer(sbh);
6212         /* Buffer got discarded which means block device got invalidated */
6213         if (!buffer_mapped(sbh)) {
6214                 unlock_buffer(sbh);
6215                 return -EIO;
6216         }
6217
6218         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
6219                 /*
6220                  * Oh, dear.  A previous attempt to write the
6221                  * superblock failed.  This could happen because the
6222                  * USB device was yanked out.  Or it could happen to
6223                  * be a transient write error and maybe the block will
6224                  * be remapped.  Nothing we can do but to retry the
6225                  * write and hope for the best.
6226                  */
6227                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
6228                        "superblock detected");
6229                 clear_buffer_write_io_error(sbh);
6230                 set_buffer_uptodate(sbh);
6231         }
6232         get_bh(sbh);
6233         /* Clear potential dirty bit if it was journalled update */
6234         clear_buffer_dirty(sbh);
6235         sbh->b_end_io = end_buffer_write_sync;
6236         submit_bh(REQ_OP_WRITE | REQ_SYNC |
6237                   (test_opt(sb, BARRIER) ? REQ_FUA : 0), sbh);
6238         wait_on_buffer(sbh);
6239         if (buffer_write_io_error(sbh)) {
6240                 ext4_msg(sb, KERN_ERR, "I/O error while writing "
6241                        "superblock");
6242                 clear_buffer_write_io_error(sbh);
6243                 set_buffer_uptodate(sbh);
6244                 return -EIO;
6245         }
6246         return 0;
6247 }
6248
6249 /*
6250  * Have we just finished recovery?  If so, and if we are mounting (or
6251  * remounting) the filesystem readonly, then we will end up with a
6252  * consistent fs on disk.  Record that fact.
6253  */
6254 static int ext4_mark_recovery_complete(struct super_block *sb,
6255                                        struct ext4_super_block *es)
6256 {
6257         int err;
6258         journal_t *journal = EXT4_SB(sb)->s_journal;
6259
6260         if (!ext4_has_feature_journal(sb)) {
6261                 if (journal != NULL) {
6262                         ext4_error(sb, "Journal got removed while the fs was "
6263                                    "mounted!");
6264                         return -EFSCORRUPTED;
6265                 }
6266                 return 0;
6267         }
6268         jbd2_journal_lock_updates(journal);
6269         err = jbd2_journal_flush(journal, 0);
6270         if (err < 0)
6271                 goto out;
6272
6273         if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6274             ext4_has_feature_orphan_present(sb))) {
6275                 if (!ext4_orphan_file_empty(sb)) {
6276                         ext4_error(sb, "Orphan file not empty on read-only fs.");
6277                         err = -EFSCORRUPTED;
6278                         goto out;
6279                 }
6280                 ext4_clear_feature_journal_needs_recovery(sb);
6281                 ext4_clear_feature_orphan_present(sb);
6282                 ext4_commit_super(sb);
6283         }
6284 out:
6285         jbd2_journal_unlock_updates(journal);
6286         return err;
6287 }
6288
6289 /*
6290  * If we are mounting (or read-write remounting) a filesystem whose journal
6291  * has recorded an error from a previous lifetime, move that error to the
6292  * main filesystem now.
6293  */
6294 static int ext4_clear_journal_err(struct super_block *sb,
6295                                    struct ext4_super_block *es)
6296 {
6297         journal_t *journal;
6298         int j_errno;
6299         const char *errstr;
6300
6301         if (!ext4_has_feature_journal(sb)) {
6302                 ext4_error(sb, "Journal got removed while the fs was mounted!");
6303                 return -EFSCORRUPTED;
6304         }
6305
6306         journal = EXT4_SB(sb)->s_journal;
6307
6308         /*
6309          * Now check for any error status which may have been recorded in the
6310          * journal by a prior ext4_error() or ext4_abort()
6311          */
6312
6313         j_errno = jbd2_journal_errno(journal);
6314         if (j_errno) {
6315                 char nbuf[16];
6316
6317                 errstr = ext4_decode_error(sb, j_errno, nbuf);
6318                 ext4_warning(sb, "Filesystem error recorded "
6319                              "from previous mount: %s", errstr);
6320
6321                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6322                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6323                 j_errno = ext4_commit_super(sb);
6324                 if (j_errno)
6325                         return j_errno;
6326                 ext4_warning(sb, "Marked fs in need of filesystem check.");
6327
6328                 jbd2_journal_clear_err(journal);
6329                 jbd2_journal_update_sb_errno(journal);
6330         }
6331         return 0;
6332 }
6333
6334 /*
6335  * Force the running and committing transactions to commit,
6336  * and wait on the commit.
6337  */
6338 int ext4_force_commit(struct super_block *sb)
6339 {
6340         return ext4_journal_force_commit(EXT4_SB(sb)->s_journal);
6341 }
6342
6343 static int ext4_sync_fs(struct super_block *sb, int wait)
6344 {
6345         int ret = 0;
6346         tid_t target;
6347         bool needs_barrier = false;
6348         struct ext4_sb_info *sbi = EXT4_SB(sb);
6349
6350         if (unlikely(ext4_forced_shutdown(sb)))
6351                 return -EIO;
6352
6353         trace_ext4_sync_fs(sb, wait);
6354         flush_workqueue(sbi->rsv_conversion_wq);
6355         /*
6356          * Writeback quota in non-journalled quota case - journalled quota has
6357          * no dirty dquots
6358          */
6359         dquot_writeback_dquots(sb, -1);
6360         /*
6361          * Data writeback is possible w/o journal transaction, so barrier must
6362          * being sent at the end of the function. But we can skip it if
6363          * transaction_commit will do it for us.
6364          */
6365         if (sbi->s_journal) {
6366                 target = jbd2_get_latest_transaction(sbi->s_journal);
6367                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6368                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6369                         needs_barrier = true;
6370
6371                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6372                         if (wait)
6373                                 ret = jbd2_log_wait_commit(sbi->s_journal,
6374                                                            target);
6375                 }
6376         } else if (wait && test_opt(sb, BARRIER))
6377                 needs_barrier = true;
6378         if (needs_barrier) {
6379                 int err;
6380                 err = blkdev_issue_flush(sb->s_bdev);
6381                 if (!ret)
6382                         ret = err;
6383         }
6384
6385         return ret;
6386 }
6387
6388 /*
6389  * LVM calls this function before a (read-only) snapshot is created.  This
6390  * gives us a chance to flush the journal completely and mark the fs clean.
6391  *
6392  * Note that only this function cannot bring a filesystem to be in a clean
6393  * state independently. It relies on upper layer to stop all data & metadata
6394  * modifications.
6395  */
6396 static int ext4_freeze(struct super_block *sb)
6397 {
6398         int error = 0;
6399         journal_t *journal = EXT4_SB(sb)->s_journal;
6400
6401         if (journal) {
6402                 /* Now we set up the journal barrier. */
6403                 jbd2_journal_lock_updates(journal);
6404
6405                 /*
6406                  * Don't clear the needs_recovery flag if we failed to
6407                  * flush the journal.
6408                  */
6409                 error = jbd2_journal_flush(journal, 0);
6410                 if (error < 0)
6411                         goto out;
6412
6413                 /* Journal blocked and flushed, clear needs_recovery flag. */
6414                 ext4_clear_feature_journal_needs_recovery(sb);
6415                 if (ext4_orphan_file_empty(sb))
6416                         ext4_clear_feature_orphan_present(sb);
6417         }
6418
6419         error = ext4_commit_super(sb);
6420 out:
6421         if (journal)
6422                 /* we rely on upper layer to stop further updates */
6423                 jbd2_journal_unlock_updates(journal);
6424         return error;
6425 }
6426
6427 /*
6428  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6429  * flag here, even though the filesystem is not technically dirty yet.
6430  */
6431 static int ext4_unfreeze(struct super_block *sb)
6432 {
6433         if (ext4_forced_shutdown(sb))
6434                 return 0;
6435
6436         if (EXT4_SB(sb)->s_journal) {
6437                 /* Reset the needs_recovery flag before the fs is unlocked. */
6438                 ext4_set_feature_journal_needs_recovery(sb);
6439                 if (ext4_has_feature_orphan_file(sb))
6440                         ext4_set_feature_orphan_present(sb);
6441         }
6442
6443         ext4_commit_super(sb);
6444         return 0;
6445 }
6446
6447 /*
6448  * Structure to save mount options for ext4_remount's benefit
6449  */
6450 struct ext4_mount_options {
6451         unsigned long s_mount_opt;
6452         unsigned long s_mount_opt2;
6453         kuid_t s_resuid;
6454         kgid_t s_resgid;
6455         unsigned long s_commit_interval;
6456         u32 s_min_batch_time, s_max_batch_time;
6457 #ifdef CONFIG_QUOTA
6458         int s_jquota_fmt;
6459         char *s_qf_names[EXT4_MAXQUOTAS];
6460 #endif
6461 };
6462
6463 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6464 {
6465         struct ext4_fs_context *ctx = fc->fs_private;
6466         struct ext4_super_block *es;
6467         struct ext4_sb_info *sbi = EXT4_SB(sb);
6468         unsigned long old_sb_flags;
6469         struct ext4_mount_options old_opts;
6470         ext4_group_t g;
6471         int err = 0;
6472         int alloc_ctx;
6473 #ifdef CONFIG_QUOTA
6474         int enable_quota = 0;
6475         int i, j;
6476         char *to_free[EXT4_MAXQUOTAS];
6477 #endif
6478
6479
6480         /* Store the original options */
6481         old_sb_flags = sb->s_flags;
6482         old_opts.s_mount_opt = sbi->s_mount_opt;
6483         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6484         old_opts.s_resuid = sbi->s_resuid;
6485         old_opts.s_resgid = sbi->s_resgid;
6486         old_opts.s_commit_interval = sbi->s_commit_interval;
6487         old_opts.s_min_batch_time = sbi->s_min_batch_time;
6488         old_opts.s_max_batch_time = sbi->s_max_batch_time;
6489 #ifdef CONFIG_QUOTA
6490         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6491         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6492                 if (sbi->s_qf_names[i]) {
6493                         char *qf_name = get_qf_name(sb, sbi, i);
6494
6495                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6496                         if (!old_opts.s_qf_names[i]) {
6497                                 for (j = 0; j < i; j++)
6498                                         kfree(old_opts.s_qf_names[j]);
6499                                 return -ENOMEM;
6500                         }
6501                 } else
6502                         old_opts.s_qf_names[i] = NULL;
6503 #endif
6504         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)) {
6505                 if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6506                         ctx->journal_ioprio =
6507                                 sbi->s_journal->j_task->io_context->ioprio;
6508                 else
6509                         ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
6510
6511         }
6512
6513         if ((ctx->spec & EXT4_SPEC_s_stripe) &&
6514             ext4_is_stripe_incompatible(sb, ctx->s_stripe)) {
6515                 ext4_msg(sb, KERN_WARNING,
6516                          "stripe (%lu) is not aligned with cluster size (%u), "
6517                          "stripe is disabled",
6518                          ctx->s_stripe, sbi->s_cluster_ratio);
6519                 ctx->s_stripe = 0;
6520         }
6521
6522         /*
6523          * Changing the DIOREAD_NOLOCK or DELALLOC mount options may cause
6524          * two calls to ext4_should_dioread_nolock() to return inconsistent
6525          * values, triggering WARN_ON in ext4_add_complete_io(). we grab
6526          * here s_writepages_rwsem to avoid race between writepages ops and
6527          * remount.
6528          */
6529         alloc_ctx = ext4_writepages_down_write(sb);
6530         ext4_apply_options(fc, sb);
6531         ext4_writepages_up_write(sb, alloc_ctx);
6532
6533         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6534             test_opt(sb, JOURNAL_CHECKSUM)) {
6535                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6536                          "during remount not supported; ignoring");
6537                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6538         }
6539
6540         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6541                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6542                         ext4_msg(sb, KERN_ERR, "can't mount with "
6543                                  "both data=journal and delalloc");
6544                         err = -EINVAL;
6545                         goto restore_opts;
6546                 }
6547                 if (test_opt(sb, DIOREAD_NOLOCK)) {
6548                         ext4_msg(sb, KERN_ERR, "can't mount with "
6549                                  "both data=journal and dioread_nolock");
6550                         err = -EINVAL;
6551                         goto restore_opts;
6552                 }
6553         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6554                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6555                         ext4_msg(sb, KERN_ERR, "can't mount with "
6556                                 "journal_async_commit in data=ordered mode");
6557                         err = -EINVAL;
6558                         goto restore_opts;
6559                 }
6560         }
6561
6562         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6563                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6564                 err = -EINVAL;
6565                 goto restore_opts;
6566         }
6567
6568         if ((old_opts.s_mount_opt & EXT4_MOUNT_DELALLOC) &&
6569             !test_opt(sb, DELALLOC)) {
6570                 ext4_msg(sb, KERN_ERR, "can't disable delalloc during remount");
6571                 err = -EINVAL;
6572                 goto restore_opts;
6573         }
6574
6575         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6576                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6577
6578         es = sbi->s_es;
6579
6580         if (sbi->s_journal) {
6581                 ext4_init_journal_params(sb, sbi->s_journal);
6582                 set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6583         }
6584
6585         /* Flush outstanding errors before changing fs state */
6586         flush_work(&sbi->s_sb_upd_work);
6587
6588         if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6589                 if (ext4_forced_shutdown(sb)) {
6590                         err = -EROFS;
6591                         goto restore_opts;
6592                 }
6593
6594                 if (fc->sb_flags & SB_RDONLY) {
6595                         err = sync_filesystem(sb);
6596                         if (err < 0)
6597                                 goto restore_opts;
6598                         err = dquot_suspend(sb, -1);
6599                         if (err < 0)
6600                                 goto restore_opts;
6601
6602                         /*
6603                          * First of all, the unconditional stuff we have to do
6604                          * to disable replay of the journal when we next remount
6605                          */
6606                         sb->s_flags |= SB_RDONLY;
6607
6608                         /*
6609                          * OK, test if we are remounting a valid rw partition
6610                          * readonly, and if so set the rdonly flag and then
6611                          * mark the partition as valid again.
6612                          */
6613                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6614                             (sbi->s_mount_state & EXT4_VALID_FS))
6615                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
6616
6617                         if (sbi->s_journal) {
6618                                 /*
6619                                  * We let remount-ro finish even if marking fs
6620                                  * as clean failed...
6621                                  */
6622                                 ext4_mark_recovery_complete(sb, es);
6623                         }
6624                 } else {
6625                         /* Make sure we can mount this feature set readwrite */
6626                         if (ext4_has_feature_readonly(sb) ||
6627                             !ext4_feature_set_ok(sb, 0)) {
6628                                 err = -EROFS;
6629                                 goto restore_opts;
6630                         }
6631                         /*
6632                          * Make sure the group descriptor checksums
6633                          * are sane.  If they aren't, refuse to remount r/w.
6634                          */
6635                         for (g = 0; g < sbi->s_groups_count; g++) {
6636                                 struct ext4_group_desc *gdp =
6637                                         ext4_get_group_desc(sb, g, NULL);
6638
6639                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6640                                         ext4_msg(sb, KERN_ERR,
6641                "ext4_remount: Checksum for group %u failed (%u!=%u)",
6642                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6643                                                le16_to_cpu(gdp->bg_checksum));
6644                                         err = -EFSBADCRC;
6645                                         goto restore_opts;
6646                                 }
6647                         }
6648
6649                         /*
6650                          * If we have an unprocessed orphan list hanging
6651                          * around from a previously readonly bdev mount,
6652                          * require a full umount/remount for now.
6653                          */
6654                         if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6655                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
6656                                        "remount RDWR because of unprocessed "
6657                                        "orphan inode list.  Please "
6658                                        "umount/remount instead");
6659                                 err = -EINVAL;
6660                                 goto restore_opts;
6661                         }
6662
6663                         /*
6664                          * Mounting a RDONLY partition read-write, so reread
6665                          * and store the current valid flag.  (It may have
6666                          * been changed by e2fsck since we originally mounted
6667                          * the partition.)
6668                          */
6669                         if (sbi->s_journal) {
6670                                 err = ext4_clear_journal_err(sb, es);
6671                                 if (err)
6672                                         goto restore_opts;
6673                         }
6674                         sbi->s_mount_state = (le16_to_cpu(es->s_state) &
6675                                               ~EXT4_FC_REPLAY);
6676
6677                         err = ext4_setup_super(sb, es, 0);
6678                         if (err)
6679                                 goto restore_opts;
6680
6681                         sb->s_flags &= ~SB_RDONLY;
6682                         if (ext4_has_feature_mmp(sb)) {
6683                                 err = ext4_multi_mount_protect(sb,
6684                                                 le64_to_cpu(es->s_mmp_block));
6685                                 if (err)
6686                                         goto restore_opts;
6687                         }
6688 #ifdef CONFIG_QUOTA
6689                         enable_quota = 1;
6690 #endif
6691                 }
6692         }
6693
6694         /*
6695          * Handle creation of system zone data early because it can fail.
6696          * Releasing of existing data is done when we are sure remount will
6697          * succeed.
6698          */
6699         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6700                 err = ext4_setup_system_zone(sb);
6701                 if (err)
6702                         goto restore_opts;
6703         }
6704
6705         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6706                 err = ext4_commit_super(sb);
6707                 if (err)
6708                         goto restore_opts;
6709         }
6710
6711 #ifdef CONFIG_QUOTA
6712         if (enable_quota) {
6713                 if (sb_any_quota_suspended(sb))
6714                         dquot_resume(sb, -1);
6715                 else if (ext4_has_feature_quota(sb)) {
6716                         err = ext4_enable_quotas(sb);
6717                         if (err)
6718                                 goto restore_opts;
6719                 }
6720         }
6721         /* Release old quota file names */
6722         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6723                 kfree(old_opts.s_qf_names[i]);
6724 #endif
6725         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6726                 ext4_release_system_zone(sb);
6727
6728         /*
6729          * Reinitialize lazy itable initialization thread based on
6730          * current settings
6731          */
6732         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6733                 ext4_unregister_li_request(sb);
6734         else {
6735                 ext4_group_t first_not_zeroed;
6736                 first_not_zeroed = ext4_has_uninit_itable(sb);
6737                 ext4_register_li_request(sb, first_not_zeroed);
6738         }
6739
6740         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6741                 ext4_stop_mmpd(sbi);
6742
6743         /*
6744          * Handle aborting the filesystem as the last thing during remount to
6745          * avoid obsure errors during remount when some option changes fail to
6746          * apply due to shutdown filesystem.
6747          */
6748         if (test_opt2(sb, ABORT))
6749                 ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6750
6751         return 0;
6752
6753 restore_opts:
6754         /*
6755          * If there was a failing r/w to ro transition, we may need to
6756          * re-enable quota
6757          */
6758         if (sb_rdonly(sb) && !(old_sb_flags & SB_RDONLY) &&
6759             sb_any_quota_suspended(sb))
6760                 dquot_resume(sb, -1);
6761
6762         alloc_ctx = ext4_writepages_down_write(sb);
6763         sb->s_flags = old_sb_flags;
6764         sbi->s_mount_opt = old_opts.s_mount_opt;
6765         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6766         sbi->s_resuid = old_opts.s_resuid;
6767         sbi->s_resgid = old_opts.s_resgid;
6768         sbi->s_commit_interval = old_opts.s_commit_interval;
6769         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6770         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6771         ext4_writepages_up_write(sb, alloc_ctx);
6772
6773         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6774                 ext4_release_system_zone(sb);
6775 #ifdef CONFIG_QUOTA
6776         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6777         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6778                 to_free[i] = get_qf_name(sb, sbi, i);
6779                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6780         }
6781         synchronize_rcu();
6782         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6783                 kfree(to_free[i]);
6784 #endif
6785         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6786                 ext4_stop_mmpd(sbi);
6787         return err;
6788 }
6789
6790 static int ext4_reconfigure(struct fs_context *fc)
6791 {
6792         struct super_block *sb = fc->root->d_sb;
6793         int ret;
6794
6795         fc->s_fs_info = EXT4_SB(sb);
6796
6797         ret = ext4_check_opt_consistency(fc, sb);
6798         if (ret < 0)
6799                 return ret;
6800
6801         ret = __ext4_remount(fc, sb);
6802         if (ret < 0)
6803                 return ret;
6804
6805         ext4_msg(sb, KERN_INFO, "re-mounted %pU %s. Quota mode: %s.",
6806                  &sb->s_uuid, sb_rdonly(sb) ? "ro" : "r/w",
6807                  ext4_quota_mode(sb));
6808
6809         return 0;
6810 }
6811
6812 #ifdef CONFIG_QUOTA
6813 static int ext4_statfs_project(struct super_block *sb,
6814                                kprojid_t projid, struct kstatfs *buf)
6815 {
6816         struct kqid qid;
6817         struct dquot *dquot;
6818         u64 limit;
6819         u64 curblock;
6820
6821         qid = make_kqid_projid(projid);
6822         dquot = dqget(sb, qid);
6823         if (IS_ERR(dquot))
6824                 return PTR_ERR(dquot);
6825         spin_lock(&dquot->dq_dqb_lock);
6826
6827         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6828                              dquot->dq_dqb.dqb_bhardlimit);
6829         limit >>= sb->s_blocksize_bits;
6830
6831         if (limit && buf->f_blocks > limit) {
6832                 curblock = (dquot->dq_dqb.dqb_curspace +
6833                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6834                 buf->f_blocks = limit;
6835                 buf->f_bfree = buf->f_bavail =
6836                         (buf->f_blocks > curblock) ?
6837                          (buf->f_blocks - curblock) : 0;
6838         }
6839
6840         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6841                              dquot->dq_dqb.dqb_ihardlimit);
6842         if (limit && buf->f_files > limit) {
6843                 buf->f_files = limit;
6844                 buf->f_ffree =
6845                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6846                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6847         }
6848
6849         spin_unlock(&dquot->dq_dqb_lock);
6850         dqput(dquot);
6851         return 0;
6852 }
6853 #endif
6854
6855 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6856 {
6857         struct super_block *sb = dentry->d_sb;
6858         struct ext4_sb_info *sbi = EXT4_SB(sb);
6859         struct ext4_super_block *es = sbi->s_es;
6860         ext4_fsblk_t overhead = 0, resv_blocks;
6861         s64 bfree;
6862         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6863
6864         if (!test_opt(sb, MINIX_DF))
6865                 overhead = sbi->s_overhead;
6866
6867         buf->f_type = EXT4_SUPER_MAGIC;
6868         buf->f_bsize = sb->s_blocksize;
6869         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6870         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6871                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6872         /* prevent underflow in case that few free space is available */
6873         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6874         buf->f_bavail = buf->f_bfree -
6875                         (ext4_r_blocks_count(es) + resv_blocks);
6876         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6877                 buf->f_bavail = 0;
6878         buf->f_files = le32_to_cpu(es->s_inodes_count);
6879         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6880         buf->f_namelen = EXT4_NAME_LEN;
6881         buf->f_fsid = uuid_to_fsid(es->s_uuid);
6882
6883 #ifdef CONFIG_QUOTA
6884         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6885             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6886                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6887 #endif
6888         return 0;
6889 }
6890
6891
6892 #ifdef CONFIG_QUOTA
6893
6894 /*
6895  * Helper functions so that transaction is started before we acquire dqio_sem
6896  * to keep correct lock ordering of transaction > dqio_sem
6897  */
6898 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6899 {
6900         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6901 }
6902
6903 static int ext4_write_dquot(struct dquot *dquot)
6904 {
6905         int ret, err;
6906         handle_t *handle;
6907         struct inode *inode;
6908
6909         inode = dquot_to_inode(dquot);
6910         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6911                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6912         if (IS_ERR(handle))
6913                 return PTR_ERR(handle);
6914         ret = dquot_commit(dquot);
6915         if (ret < 0)
6916                 ext4_error_err(dquot->dq_sb, -ret,
6917                                "Failed to commit dquot type %d",
6918                                dquot->dq_id.type);
6919         err = ext4_journal_stop(handle);
6920         if (!ret)
6921                 ret = err;
6922         return ret;
6923 }
6924
6925 static int ext4_acquire_dquot(struct dquot *dquot)
6926 {
6927         int ret, err;
6928         handle_t *handle;
6929
6930         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6931                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6932         if (IS_ERR(handle))
6933                 return PTR_ERR(handle);
6934         ret = dquot_acquire(dquot);
6935         if (ret < 0)
6936                 ext4_error_err(dquot->dq_sb, -ret,
6937                               "Failed to acquire dquot type %d",
6938                               dquot->dq_id.type);
6939         err = ext4_journal_stop(handle);
6940         if (!ret)
6941                 ret = err;
6942         return ret;
6943 }
6944
6945 static int ext4_release_dquot(struct dquot *dquot)
6946 {
6947         int ret, err;
6948         handle_t *handle;
6949
6950         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6951                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6952         if (IS_ERR(handle)) {
6953                 /* Release dquot anyway to avoid endless cycle in dqput() */
6954                 dquot_release(dquot);
6955                 return PTR_ERR(handle);
6956         }
6957         ret = dquot_release(dquot);
6958         if (ret < 0)
6959                 ext4_error_err(dquot->dq_sb, -ret,
6960                                "Failed to release dquot type %d",
6961                                dquot->dq_id.type);
6962         err = ext4_journal_stop(handle);
6963         if (!ret)
6964                 ret = err;
6965         return ret;
6966 }
6967
6968 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6969 {
6970         struct super_block *sb = dquot->dq_sb;
6971
6972         if (ext4_is_quota_journalled(sb)) {
6973                 dquot_mark_dquot_dirty(dquot);
6974                 return ext4_write_dquot(dquot);
6975         } else {
6976                 return dquot_mark_dquot_dirty(dquot);
6977         }
6978 }
6979
6980 static int ext4_write_info(struct super_block *sb, int type)
6981 {
6982         int ret, err;
6983         handle_t *handle;
6984
6985         /* Data block + inode block */
6986         handle = ext4_journal_start_sb(sb, EXT4_HT_QUOTA, 2);
6987         if (IS_ERR(handle))
6988                 return PTR_ERR(handle);
6989         ret = dquot_commit_info(sb, type);
6990         err = ext4_journal_stop(handle);
6991         if (!ret)
6992                 ret = err;
6993         return ret;
6994 }
6995
6996 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6997 {
6998         struct ext4_inode_info *ei = EXT4_I(inode);
6999
7000         /* The first argument of lockdep_set_subclass has to be
7001          * *exactly* the same as the argument to init_rwsem() --- in
7002          * this case, in init_once() --- or lockdep gets unhappy
7003          * because the name of the lock is set using the
7004          * stringification of the argument to init_rwsem().
7005          */
7006         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
7007         lockdep_set_subclass(&ei->i_data_sem, subclass);
7008 }
7009
7010 /*
7011  * Standard function to be called on quota_on
7012  */
7013 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
7014                          const struct path *path)
7015 {
7016         int err;
7017
7018         if (!test_opt(sb, QUOTA))
7019                 return -EINVAL;
7020
7021         /* Quotafile not on the same filesystem? */
7022         if (path->dentry->d_sb != sb)
7023                 return -EXDEV;
7024
7025         /* Quota already enabled for this file? */
7026         if (IS_NOQUOTA(d_inode(path->dentry)))
7027                 return -EBUSY;
7028
7029         /* Journaling quota? */
7030         if (EXT4_SB(sb)->s_qf_names[type]) {
7031                 /* Quotafile not in fs root? */
7032                 if (path->dentry->d_parent != sb->s_root)
7033                         ext4_msg(sb, KERN_WARNING,
7034                                 "Quota file not on filesystem root. "
7035                                 "Journaled quota will not work");
7036                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
7037         } else {
7038                 /*
7039                  * Clear the flag just in case mount options changed since
7040                  * last time.
7041                  */
7042                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
7043         }
7044
7045         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
7046         err = dquot_quota_on(sb, type, format_id, path);
7047         if (!err) {
7048                 struct inode *inode = d_inode(path->dentry);
7049                 handle_t *handle;
7050
7051                 /*
7052                  * Set inode flags to prevent userspace from messing with quota
7053                  * files. If this fails, we return success anyway since quotas
7054                  * are already enabled and this is not a hard failure.
7055                  */
7056                 inode_lock(inode);
7057                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7058                 if (IS_ERR(handle))
7059                         goto unlock_inode;
7060                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
7061                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
7062                                 S_NOATIME | S_IMMUTABLE);
7063                 err = ext4_mark_inode_dirty(handle, inode);
7064                 ext4_journal_stop(handle);
7065         unlock_inode:
7066                 inode_unlock(inode);
7067                 if (err)
7068                         dquot_quota_off(sb, type);
7069         }
7070         if (err)
7071                 lockdep_set_quota_inode(path->dentry->d_inode,
7072                                              I_DATA_SEM_NORMAL);
7073         return err;
7074 }
7075
7076 static inline bool ext4_check_quota_inum(int type, unsigned long qf_inum)
7077 {
7078         switch (type) {
7079         case USRQUOTA:
7080                 return qf_inum == EXT4_USR_QUOTA_INO;
7081         case GRPQUOTA:
7082                 return qf_inum == EXT4_GRP_QUOTA_INO;
7083         case PRJQUOTA:
7084                 return qf_inum >= EXT4_GOOD_OLD_FIRST_INO;
7085         default:
7086                 BUG();
7087         }
7088 }
7089
7090 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
7091                              unsigned int flags)
7092 {
7093         int err;
7094         struct inode *qf_inode;
7095         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7096                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7097                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7098                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7099         };
7100
7101         BUG_ON(!ext4_has_feature_quota(sb));
7102
7103         if (!qf_inums[type])
7104                 return -EPERM;
7105
7106         if (!ext4_check_quota_inum(type, qf_inums[type])) {
7107                 ext4_error(sb, "Bad quota inum: %lu, type: %d",
7108                                 qf_inums[type], type);
7109                 return -EUCLEAN;
7110         }
7111
7112         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
7113         if (IS_ERR(qf_inode)) {
7114                 ext4_error(sb, "Bad quota inode: %lu, type: %d",
7115                                 qf_inums[type], type);
7116                 return PTR_ERR(qf_inode);
7117         }
7118
7119         /* Don't account quota for quota files to avoid recursion */
7120         qf_inode->i_flags |= S_NOQUOTA;
7121         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
7122         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
7123         if (err)
7124                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
7125         iput(qf_inode);
7126
7127         return err;
7128 }
7129
7130 /* Enable usage tracking for all quota types. */
7131 int ext4_enable_quotas(struct super_block *sb)
7132 {
7133         int type, err = 0;
7134         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7135                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7136                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7137                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7138         };
7139         bool quota_mopt[EXT4_MAXQUOTAS] = {
7140                 test_opt(sb, USRQUOTA),
7141                 test_opt(sb, GRPQUOTA),
7142                 test_opt(sb, PRJQUOTA),
7143         };
7144
7145         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
7146         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
7147                 if (qf_inums[type]) {
7148                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
7149                                 DQUOT_USAGE_ENABLED |
7150                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
7151                         if (err) {
7152                                 ext4_warning(sb,
7153                                         "Failed to enable quota tracking "
7154                                         "(type=%d, err=%d, ino=%lu). "
7155                                         "Please run e2fsck to fix.", type,
7156                                         err, qf_inums[type]);
7157
7158                                 ext4_quotas_off(sb, type);
7159                                 return err;
7160                         }
7161                 }
7162         }
7163         return 0;
7164 }
7165
7166 static int ext4_quota_off(struct super_block *sb, int type)
7167 {
7168         struct inode *inode = sb_dqopt(sb)->files[type];
7169         handle_t *handle;
7170         int err;
7171
7172         /* Force all delayed allocation blocks to be allocated.
7173          * Caller already holds s_umount sem */
7174         if (test_opt(sb, DELALLOC))
7175                 sync_filesystem(sb);
7176
7177         if (!inode || !igrab(inode))
7178                 goto out;
7179
7180         err = dquot_quota_off(sb, type);
7181         if (err || ext4_has_feature_quota(sb))
7182                 goto out_put;
7183         /*
7184          * When the filesystem was remounted read-only first, we cannot cleanup
7185          * inode flags here. Bad luck but people should be using QUOTA feature
7186          * these days anyway.
7187          */
7188         if (sb_rdonly(sb))
7189                 goto out_put;
7190
7191         inode_lock(inode);
7192         /*
7193          * Update modification times of quota files when userspace can
7194          * start looking at them. If we fail, we return success anyway since
7195          * this is not a hard failure and quotas are already disabled.
7196          */
7197         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7198         if (IS_ERR(handle)) {
7199                 err = PTR_ERR(handle);
7200                 goto out_unlock;
7201         }
7202         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
7203         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
7204         inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
7205         err = ext4_mark_inode_dirty(handle, inode);
7206         ext4_journal_stop(handle);
7207 out_unlock:
7208         inode_unlock(inode);
7209 out_put:
7210         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
7211         iput(inode);
7212         return err;
7213 out:
7214         return dquot_quota_off(sb, type);
7215 }
7216
7217 /* Read data from quotafile - avoid pagecache and such because we cannot afford
7218  * acquiring the locks... As quota files are never truncated and quota code
7219  * itself serializes the operations (and no one else should touch the files)
7220  * we don't have to be afraid of races */
7221 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
7222                                size_t len, loff_t off)
7223 {
7224         struct inode *inode = sb_dqopt(sb)->files[type];
7225         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7226         int offset = off & (sb->s_blocksize - 1);
7227         int tocopy;
7228         size_t toread;
7229         struct buffer_head *bh;
7230         loff_t i_size = i_size_read(inode);
7231
7232         if (off > i_size)
7233                 return 0;
7234         if (off+len > i_size)
7235                 len = i_size-off;
7236         toread = len;
7237         while (toread > 0) {
7238                 tocopy = min_t(unsigned long, sb->s_blocksize - offset, toread);
7239                 bh = ext4_bread(NULL, inode, blk, 0);
7240                 if (IS_ERR(bh))
7241                         return PTR_ERR(bh);
7242                 if (!bh)        /* A hole? */
7243                         memset(data, 0, tocopy);
7244                 else
7245                         memcpy(data, bh->b_data+offset, tocopy);
7246                 brelse(bh);
7247                 offset = 0;
7248                 toread -= tocopy;
7249                 data += tocopy;
7250                 blk++;
7251         }
7252         return len;
7253 }
7254
7255 /* Write to quotafile (we know the transaction is already started and has
7256  * enough credits) */
7257 static ssize_t ext4_quota_write(struct super_block *sb, int type,
7258                                 const char *data, size_t len, loff_t off)
7259 {
7260         struct inode *inode = sb_dqopt(sb)->files[type];
7261         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7262         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
7263         int retries = 0;
7264         struct buffer_head *bh;
7265         handle_t *handle = journal_current_handle();
7266
7267         if (!handle) {
7268                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7269                         " cancelled because transaction is not started",
7270                         (unsigned long long)off, (unsigned long long)len);
7271                 return -EIO;
7272         }
7273         /*
7274          * Since we account only one data block in transaction credits,
7275          * then it is impossible to cross a block boundary.
7276          */
7277         if (sb->s_blocksize - offset < len) {
7278                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7279                         " cancelled because not block aligned",
7280                         (unsigned long long)off, (unsigned long long)len);
7281                 return -EIO;
7282         }
7283
7284         do {
7285                 bh = ext4_bread(handle, inode, blk,
7286                                 EXT4_GET_BLOCKS_CREATE |
7287                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
7288         } while (PTR_ERR(bh) == -ENOSPC &&
7289                  ext4_should_retry_alloc(inode->i_sb, &retries));
7290         if (IS_ERR(bh))
7291                 return PTR_ERR(bh);
7292         if (!bh)
7293                 goto out;
7294         BUFFER_TRACE(bh, "get write access");
7295         err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
7296         if (err) {
7297                 brelse(bh);
7298                 return err;
7299         }
7300         lock_buffer(bh);
7301         memcpy(bh->b_data+offset, data, len);
7302         flush_dcache_page(bh->b_page);
7303         unlock_buffer(bh);
7304         err = ext4_handle_dirty_metadata(handle, NULL, bh);
7305         brelse(bh);
7306 out:
7307         if (inode->i_size < off + len) {
7308                 i_size_write(inode, off + len);
7309                 EXT4_I(inode)->i_disksize = inode->i_size;
7310                 err2 = ext4_mark_inode_dirty(handle, inode);
7311                 if (unlikely(err2 && !err))
7312                         err = err2;
7313         }
7314         return err ? err : len;
7315 }
7316 #endif
7317
7318 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
7319 static inline void register_as_ext2(void)
7320 {
7321         int err = register_filesystem(&ext2_fs_type);
7322         if (err)
7323                 printk(KERN_WARNING
7324                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7325 }
7326
7327 static inline void unregister_as_ext2(void)
7328 {
7329         unregister_filesystem(&ext2_fs_type);
7330 }
7331
7332 static inline int ext2_feature_set_ok(struct super_block *sb)
7333 {
7334         if (ext4_has_unknown_ext2_incompat_features(sb))
7335                 return 0;
7336         if (sb_rdonly(sb))
7337                 return 1;
7338         if (ext4_has_unknown_ext2_ro_compat_features(sb))
7339                 return 0;
7340         return 1;
7341 }
7342 #else
7343 static inline void register_as_ext2(void) { }
7344 static inline void unregister_as_ext2(void) { }
7345 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7346 #endif
7347
7348 static inline void register_as_ext3(void)
7349 {
7350         int err = register_filesystem(&ext3_fs_type);
7351         if (err)
7352                 printk(KERN_WARNING
7353                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7354 }
7355
7356 static inline void unregister_as_ext3(void)
7357 {
7358         unregister_filesystem(&ext3_fs_type);
7359 }
7360
7361 static inline int ext3_feature_set_ok(struct super_block *sb)
7362 {
7363         if (ext4_has_unknown_ext3_incompat_features(sb))
7364                 return 0;
7365         if (!ext4_has_feature_journal(sb))
7366                 return 0;
7367         if (sb_rdonly(sb))
7368                 return 1;
7369         if (ext4_has_unknown_ext3_ro_compat_features(sb))
7370                 return 0;
7371         return 1;
7372 }
7373
7374 static void ext4_kill_sb(struct super_block *sb)
7375 {
7376         struct ext4_sb_info *sbi = EXT4_SB(sb);
7377         struct file *bdev_file = sbi ? sbi->s_journal_bdev_file : NULL;
7378
7379         kill_block_super(sb);
7380
7381         if (bdev_file)
7382                 bdev_fput(bdev_file);
7383 }
7384
7385 static struct file_system_type ext4_fs_type = {
7386         .owner                  = THIS_MODULE,
7387         .name                   = "ext4",
7388         .init_fs_context        = ext4_init_fs_context,
7389         .parameters             = ext4_param_specs,
7390         .kill_sb                = ext4_kill_sb,
7391         .fs_flags               = FS_REQUIRES_DEV | FS_ALLOW_IDMAP | FS_MGTIME,
7392 };
7393 MODULE_ALIAS_FS("ext4");
7394
7395 /* Shared across all ext4 file systems */
7396 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
7397
7398 static int __init ext4_init_fs(void)
7399 {
7400         int i, err;
7401
7402         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7403         ext4_li_info = NULL;
7404
7405         /* Build-time check for flags consistency */
7406         ext4_check_flag_values();
7407
7408         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
7409                 init_waitqueue_head(&ext4__ioend_wq[i]);
7410
7411         err = ext4_init_es();
7412         if (err)
7413                 return err;
7414
7415         err = ext4_init_pending();
7416         if (err)
7417                 goto out7;
7418
7419         err = ext4_init_post_read_processing();
7420         if (err)
7421                 goto out6;
7422
7423         err = ext4_init_pageio();
7424         if (err)
7425                 goto out5;
7426
7427         err = ext4_init_system_zone();
7428         if (err)
7429                 goto out4;
7430
7431         err = ext4_init_sysfs();
7432         if (err)
7433                 goto out3;
7434
7435         err = ext4_init_mballoc();
7436         if (err)
7437                 goto out2;
7438         err = init_inodecache();
7439         if (err)
7440                 goto out1;
7441
7442         err = ext4_fc_init_dentry_cache();
7443         if (err)
7444                 goto out05;
7445
7446         register_as_ext3();
7447         register_as_ext2();
7448         err = register_filesystem(&ext4_fs_type);
7449         if (err)
7450                 goto out;
7451
7452         return 0;
7453 out:
7454         unregister_as_ext2();
7455         unregister_as_ext3();
7456         ext4_fc_destroy_dentry_cache();
7457 out05:
7458         destroy_inodecache();
7459 out1:
7460         ext4_exit_mballoc();
7461 out2:
7462         ext4_exit_sysfs();
7463 out3:
7464         ext4_exit_system_zone();
7465 out4:
7466         ext4_exit_pageio();
7467 out5:
7468         ext4_exit_post_read_processing();
7469 out6:
7470         ext4_exit_pending();
7471 out7:
7472         ext4_exit_es();
7473
7474         return err;
7475 }
7476
7477 static void __exit ext4_exit_fs(void)
7478 {
7479         ext4_destroy_lazyinit_thread();
7480         unregister_as_ext2();
7481         unregister_as_ext3();
7482         unregister_filesystem(&ext4_fs_type);
7483         ext4_fc_destroy_dentry_cache();
7484         destroy_inodecache();
7485         ext4_exit_mballoc();
7486         ext4_exit_sysfs();
7487         ext4_exit_system_zone();
7488         ext4_exit_pageio();
7489         ext4_exit_post_read_processing();
7490         ext4_exit_es();
7491         ext4_exit_pending();
7492 }
7493
7494 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7495 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7496 MODULE_LICENSE("GPL");
7497 MODULE_SOFTDEP("pre: crc32c");
7498 module_init(ext4_init_fs)
7499 module_exit(ext4_exit_fs)