fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller (davem@caip.rutgers.edu), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/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)
 165 {
 166         /*
 167          * buffer's verified bit is no longer valid after reading from
 168          * disk again due to write out error, clear it to make sure we
 169          * recheck the buffer contents.
 170          */
 171         clear_buffer_verified(bh);
 172
 173         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
 174         get_bh(bh);
 175         submit_bh(REQ_OP_READ | op_flags, bh);
 176 }
 177
 178 void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
 179                          bh_end_io_t *end_io)
 180 {
 181         BUG_ON(!buffer_locked(bh));
 182
 183         if (ext4_buffer_uptodate(bh)) {
 184                 unlock_buffer(bh);
 185                 return;
 186         }
 187         __ext4_read_bh(bh, op_flags, end_io);
 188 }
 189
 190 int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags, bh_end_io_t *end_io)
 191 {
 192         BUG_ON(!buffer_locked(bh));
 193
 194         if (ext4_buffer_uptodate(bh)) {
 195                 unlock_buffer(bh);
 196                 return 0;
 197         }
 198
 199         __ext4_read_bh(bh, op_flags, end_io);
 200
 201         wait_on_buffer(bh);
 202         if (buffer_uptodate(bh))
 203                 return 0;
 204         return -EIO;
 205 }
 206
 207 int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait)
 208 {
 209         lock_buffer(bh);
 210         if (!wait) {
 211                 ext4_read_bh_nowait(bh, op_flags, NULL);
 212                 return 0;
 213         }
 214         return ext4_read_bh(bh, op_flags, NULL);
 215 }
 216
 217 /*
 218  * This works like __bread_gfp() except it uses ERR_PTR for error
 219  * returns.  Currently with sb_bread it's impossible to distinguish
 220  * between ENOMEM and EIO situations (since both result in a NULL
 221  * return.
 222  */
 223 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 224                                                sector_t block,
 225                                                blk_opf_t op_flags, gfp_t gfp)
 226 {
 227         struct buffer_head *bh;
 228         int ret;
 229
 230         bh = sb_getblk_gfp(sb, block, gfp);
 231         if (bh == NULL)
 232                 return ERR_PTR(-ENOMEM);
 233         if (ext4_buffer_uptodate(bh))
 234                 return bh;
 235
 236         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
 237         if (ret) {
 238                 put_bh(bh);
 239                 return ERR_PTR(ret);
 240         }
 241         return bh;
 242 }
 243
 244 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 245                                    blk_opf_t op_flags)
 246 {
 247         gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_inode->i_mapping,
 248                         ~__GFP_FS) | __GFP_MOVABLE;
 249
 250         return __ext4_sb_bread_gfp(sb, block, op_flags, gfp);
 251 }
 252
 253 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 254                                             sector_t block)
 255 {
 256         gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_inode->i_mapping,
 257                         ~__GFP_FS);
 258
 259         return __ext4_sb_bread_gfp(sb, block, 0, gfp);
 260 }
 261
 262 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
 263 {
 264         struct buffer_head *bh = bdev_getblk(sb->s_bdev, block,
 265                         sb->s_blocksize, GFP_NOWAIT | __GFP_NOWARN);
 266
 267         if (likely(bh)) {
 268                 if (trylock_buffer(bh))
 269                         ext4_read_bh_nowait(bh, REQ_RAHEAD, NULL);
 270                 brelse(bh);
 271         }
 272 }
 273
 274 static int ext4_verify_csum_type(struct super_block *sb,
 275                                  struct ext4_super_block *es)
 276 {
 277         if (!ext4_has_feature_metadata_csum(sb))
 278                 return 1;
 279
 280         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 281 }
 282
 283 __le32 ext4_superblock_csum(struct super_block *sb,
 284                             struct ext4_super_block *es)
 285 {
 286         struct ext4_sb_info *sbi = EXT4_SB(sb);
 287         int offset = offsetof(struct ext4_super_block, s_checksum);
 288         __u32 csum;
 289
 290         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 291
 292         return cpu_to_le32(csum);
 293 }
 294
 295 static int ext4_superblock_csum_verify(struct super_block *sb,
 296                                        struct ext4_super_block *es)
 297 {
 298         if (!ext4_has_metadata_csum(sb))
 299                 return 1;
 300
 301         return es->s_checksum == ext4_superblock_csum(sb, es);
 302 }
 303
 304 void ext4_superblock_csum_set(struct super_block *sb)
 305 {
 306         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 307
 308         if (!ext4_has_metadata_csum(sb))
 309                 return;
 310
 311         es->s_checksum = ext4_superblock_csum(sb, es);
 312 }
 313
 314 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 315                                struct ext4_group_desc *bg)
 316 {
 317         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 318                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 319                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 320 }
 321
 322 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 323                                struct ext4_group_desc *bg)
 324 {
 325         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 326                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 327                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 328 }
 329
 330 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 331                               struct ext4_group_desc *bg)
 332 {
 333         return le32_to_cpu(bg->bg_inode_table_lo) |
 334                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 335                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 336 }
 337
 338 __u32 ext4_free_group_clusters(struct super_block *sb,
 339                                struct ext4_group_desc *bg)
 340 {
 341         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 342                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 343                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 344 }
 345
 346 __u32 ext4_free_inodes_count(struct super_block *sb,
 347                               struct ext4_group_desc *bg)
 348 {
 349         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 350                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 351                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 352 }
 353
 354 __u32 ext4_used_dirs_count(struct super_block *sb,
 355                               struct ext4_group_desc *bg)
 356 {
 357         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 358                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 359                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 360 }
 361
 362 __u32 ext4_itable_unused_count(struct super_block *sb,
 363                               struct ext4_group_desc *bg)
 364 {
 365         return le16_to_cpu(bg->bg_itable_unused_lo) |
 366                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 367                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 368 }
 369
 370 void ext4_block_bitmap_set(struct super_block *sb,
 371                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 372 {
 373         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 374         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 375                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 376 }
 377
 378 void ext4_inode_bitmap_set(struct super_block *sb,
 379                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 380 {
 381         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 382         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 383                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 384 }
 385
 386 void ext4_inode_table_set(struct super_block *sb,
 387                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 388 {
 389         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 390         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 391                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 392 }
 393
 394 void ext4_free_group_clusters_set(struct super_block *sb,
 395                                   struct ext4_group_desc *bg, __u32 count)
 396 {
 397         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 398         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 399                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 400 }
 401
 402 void ext4_free_inodes_set(struct super_block *sb,
 403                           struct ext4_group_desc *bg, __u32 count)
 404 {
 405         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 406         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 407                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 408 }
 409
 410 void ext4_used_dirs_set(struct super_block *sb,
 411                           struct ext4_group_desc *bg, __u32 count)
 412 {
 413         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 414         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 415                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 416 }
 417
 418 void ext4_itable_unused_set(struct super_block *sb,
 419                           struct ext4_group_desc *bg, __u32 count)
 420 {
 421         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 422         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 423                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 424 }
 425
 426 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi, time64_t now)
 427 {
 428         now = clamp_val(now, 0, (1ull << 40) - 1);
 429
 430         *lo = cpu_to_le32(lower_32_bits(now));
 431         *hi = upper_32_bits(now);
 432 }
 433
 434 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 435 {
 436         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 437 }
 438 #define ext4_update_tstamp(es, tstamp) \
 439         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi, \
 440                              ktime_get_real_seconds())
 441 #define ext4_get_tstamp(es, tstamp) \
 442         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 443
 444 #define EXT4_SB_REFRESH_INTERVAL_SEC (3600) /* seconds (1 hour) */
 445 #define EXT4_SB_REFRESH_INTERVAL_KB (16384) /* kilobytes (16MB) */
 446
 447 /*
 448  * The ext4_maybe_update_superblock() function checks and updates the
 449  * superblock if needed.
 450  *
 451  * This function is designed to update the on-disk superblock only under
 452  * certain conditions to prevent excessive disk writes and unnecessary
 453  * waking of the disk from sleep. The superblock will be updated if:
 454  * 1. More than an hour has passed since the last superblock update, and
 455  * 2. More than 16MB have been written since the last superblock update.
 456  *
 457  * @sb: The superblock
 458  */
 459 static void ext4_maybe_update_superblock(struct super_block *sb)
 460 {
 461         struct ext4_sb_info *sbi = EXT4_SB(sb);
 462         struct ext4_super_block *es = sbi->s_es;
 463         journal_t *journal = sbi->s_journal;
 464         time64_t now;
 465         __u64 last_update;
 466         __u64 lifetime_write_kbytes;
 467         __u64 diff_size;
 468
 469         if (sb_rdonly(sb) || !(sb->s_flags & SB_ACTIVE) ||
 470             !journal || (journal->j_flags & JBD2_UNMOUNT))
 471                 return;
 472
 473         now = ktime_get_real_seconds();
 474         last_update = ext4_get_tstamp(es, s_wtime);
 475
 476         if (likely(now - last_update < EXT4_SB_REFRESH_INTERVAL_SEC))
 477                 return;
 478
 479         lifetime_write_kbytes = sbi->s_kbytes_written +
 480                 ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
 481                   sbi->s_sectors_written_start) >> 1);
 482
 483         /* Get the number of kilobytes not written to disk to account
 484          * for statistics and compare with a multiple of 16 MB. This
 485          * is used to determine when the next superblock commit should
 486          * occur (i.e. not more often than once per 16MB if there was
 487          * less written in an hour).
 488          */
 489         diff_size = lifetime_write_kbytes - le64_to_cpu(es->s_kbytes_written);
 490
 491         if (diff_size > EXT4_SB_REFRESH_INTERVAL_KB)
 492                 schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
 493 }
 494
 495 /*
 496  * The del_gendisk() function uninitializes the disk-specific data
 497  * structures, including the bdi structure, without telling anyone
 498  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 499  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 500  * This is a kludge to prevent these oops until we can put in a proper
 501  * hook in del_gendisk() to inform the VFS and file system layers.
 502  */
 503 static int block_device_ejected(struct super_block *sb)
 504 {
 505         struct inode *bd_inode = sb->s_bdev->bd_inode;
 506         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 507
 508         return bdi->dev == NULL;
 509 }
 510
 511 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 512 {
 513         struct super_block              *sb = journal->j_private;
 514         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 515         int                             error = is_journal_aborted(journal);
 516         struct ext4_journal_cb_entry    *jce;
 517
 518         BUG_ON(txn->t_state == T_FINISHED);
 519
 520         ext4_process_freed_data(sb, txn->t_tid);
 521         ext4_maybe_update_superblock(sb);
 522
 523         spin_lock(&sbi->s_md_lock);
 524         while (!list_empty(&txn->t_private_list)) {
 525                 jce = list_entry(txn->t_private_list.next,
 526                                  struct ext4_journal_cb_entry, jce_list);
 527                 list_del_init(&jce->jce_list);
 528                 spin_unlock(&sbi->s_md_lock);
 529                 jce->jce_func(sb, jce, error);
 530                 spin_lock(&sbi->s_md_lock);
 531         }
 532         spin_unlock(&sbi->s_md_lock);
 533 }
 534
 535 /*
 536  * This writepage callback for write_cache_pages()
 537  * takes care of a few cases after page cleaning.
 538  *
 539  * write_cache_pages() already checks for dirty pages
 540  * and calls clear_page_dirty_for_io(), which we want,
 541  * to write protect the pages.
 542  *
 543  * However, we may have to redirty a page (see below.)
 544  */
 545 static int ext4_journalled_writepage_callback(struct folio *folio,
 546                                               struct writeback_control *wbc,
 547                                               void *data)
 548 {
 549         transaction_t *transaction = (transaction_t *) data;
 550         struct buffer_head *bh, *head;
 551         struct journal_head *jh;
 552
 553         bh = head = folio_buffers(folio);
 554         do {
 555                 /*
 556                  * We have to redirty a page in these cases:
 557                  * 1) If buffer is dirty, it means the page was dirty because it
 558                  * contains a buffer that needs checkpointing. So the dirty bit
 559                  * needs to be preserved so that checkpointing writes the buffer
 560                  * properly.
 561                  * 2) If buffer is not part of the committing transaction
 562                  * (we may have just accidentally come across this buffer because
 563                  * inode range tracking is not exact) or if the currently running
 564                  * transaction already contains this buffer as well, dirty bit
 565                  * needs to be preserved so that the buffer gets writeprotected
 566                  * properly on running transaction's commit.
 567                  */
 568                 jh = bh2jh(bh);
 569                 if (buffer_dirty(bh) ||
 570                     (jh && (jh->b_transaction != transaction ||
 571                             jh->b_next_transaction))) {
 572                         folio_redirty_for_writepage(wbc, folio);
 573                         goto out;
 574                 }
 575         } while ((bh = bh->b_this_page) != head);
 576
 577 out:
 578         return AOP_WRITEPAGE_ACTIVATE;
 579 }
 580
 581 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
 582 {
 583         struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
 584         struct writeback_control wbc = {
 585                 .sync_mode =  WB_SYNC_ALL,
 586                 .nr_to_write = LONG_MAX,
 587                 .range_start = jinode->i_dirty_start,
 588                 .range_end = jinode->i_dirty_end,
 589         };
 590
 591         return write_cache_pages(mapping, &wbc,
 592                                  ext4_journalled_writepage_callback,
 593                                  jinode->i_transaction);
 594 }
 595
 596 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
 597 {
 598         int ret;
 599
 600         if (ext4_should_journal_data(jinode->i_vfs_inode))
 601                 ret = ext4_journalled_submit_inode_data_buffers(jinode);
 602         else
 603                 ret = ext4_normal_submit_inode_data_buffers(jinode);
 604         return ret;
 605 }
 606
 607 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
 608 {
 609         int ret = 0;
 610
 611         if (!ext4_should_journal_data(jinode->i_vfs_inode))
 612                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
 613
 614         return ret;
 615 }
 616
 617 static bool system_going_down(void)
 618 {
 619         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 620                 || system_state == SYSTEM_RESTART;
 621 }
 622
 623 struct ext4_err_translation {
 624         int code;
 625         int errno;
 626 };
 627
 628 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
 629
 630 static struct ext4_err_translation err_translation[] = {
 631         EXT4_ERR_TRANSLATE(EIO),
 632         EXT4_ERR_TRANSLATE(ENOMEM),
 633         EXT4_ERR_TRANSLATE(EFSBADCRC),
 634         EXT4_ERR_TRANSLATE(EFSCORRUPTED),
 635         EXT4_ERR_TRANSLATE(ENOSPC),
 636         EXT4_ERR_TRANSLATE(ENOKEY),
 637         EXT4_ERR_TRANSLATE(EROFS),
 638         EXT4_ERR_TRANSLATE(EFBIG),
 639         EXT4_ERR_TRANSLATE(EEXIST),
 640         EXT4_ERR_TRANSLATE(ERANGE),
 641         EXT4_ERR_TRANSLATE(EOVERFLOW),
 642         EXT4_ERR_TRANSLATE(EBUSY),
 643         EXT4_ERR_TRANSLATE(ENOTDIR),
 644         EXT4_ERR_TRANSLATE(ENOTEMPTY),
 645         EXT4_ERR_TRANSLATE(ESHUTDOWN),
 646         EXT4_ERR_TRANSLATE(EFAULT),
 647 };
 648
 649 static int ext4_errno_to_code(int errno)
 650 {
 651         int i;
 652
 653         for (i = 0; i < ARRAY_SIZE(err_translation); i++)
 654                 if (err_translation[i].errno == errno)
 655                         return err_translation[i].code;
 656         return EXT4_ERR_UNKNOWN;
 657 }
 658
 659 static void save_error_info(struct super_block *sb, int error,
 660                             __u32 ino, __u64 block,
 661                             const char *func, unsigned int line)
 662 {
 663         struct ext4_sb_info *sbi = EXT4_SB(sb);
 664
 665         /* We default to EFSCORRUPTED error... */
 666         if (error == 0)
 667                 error = EFSCORRUPTED;
 668
 669         spin_lock(&sbi->s_error_lock);
 670         sbi->s_add_error_count++;
 671         sbi->s_last_error_code = error;
 672         sbi->s_last_error_line = line;
 673         sbi->s_last_error_ino = ino;
 674         sbi->s_last_error_block = block;
 675         sbi->s_last_error_func = func;
 676         sbi->s_last_error_time = ktime_get_real_seconds();
 677         if (!sbi->s_first_error_time) {
 678                 sbi->s_first_error_code = error;
 679                 sbi->s_first_error_line = line;
 680                 sbi->s_first_error_ino = ino;
 681                 sbi->s_first_error_block = block;
 682                 sbi->s_first_error_func = func;
 683                 sbi->s_first_error_time = sbi->s_last_error_time;
 684         }
 685         spin_unlock(&sbi->s_error_lock);
 686 }
 687
 688 /* Deal with the reporting of failure conditions on a filesystem such as
 689  * inconsistencies detected or read IO failures.
 690  *
 691  * On ext2, we can store the error state of the filesystem in the
 692  * superblock.  That is not possible on ext4, because we may have other
 693  * write ordering constraints on the superblock which prevent us from
 694  * writing it out straight away; and given that the journal is about to
 695  * be aborted, we can't rely on the current, or future, transactions to
 696  * write out the superblock safely.
 697  *
 698  * We'll just use the jbd2_journal_abort() error code to record an error in
 699  * the journal instead.  On recovery, the journal will complain about
 700  * that error until we've noted it down and cleared it.
 701  *
 702  * If force_ro is set, we unconditionally force the filesystem into an
 703  * ABORT|READONLY state, unless the error response on the fs has been set to
 704  * panic in which case we take the easy way out and panic immediately. This is
 705  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
 706  * at a critical moment in log management.
 707  */
 708 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
 709                               __u32 ino, __u64 block,
 710                               const char *func, unsigned int line)
 711 {
 712         journal_t *journal = EXT4_SB(sb)->s_journal;
 713         bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
 714
 715         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 716         if (test_opt(sb, WARN_ON_ERROR))
 717                 WARN_ON_ONCE(1);
 718
 719         if (!continue_fs && !sb_rdonly(sb)) {
 720                 set_bit(EXT4_FLAGS_SHUTDOWN, &EXT4_SB(sb)->s_ext4_flags);
 721                 if (journal)
 722                         jbd2_journal_abort(journal, -EIO);
 723         }
 724
 725         if (!bdev_read_only(sb->s_bdev)) {
 726                 save_error_info(sb, error, ino, block, func, line);
 727                 /*
 728                  * In case the fs should keep running, we need to writeout
 729                  * superblock through the journal. Due to lock ordering
 730                  * constraints, it may not be safe to do it right here so we
 731                  * defer superblock flushing to a workqueue.
 732                  */
 733                 if (continue_fs && journal)
 734                         schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
 735                 else
 736                         ext4_commit_super(sb);
 737         }
 738
 739         /*
 740          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 741          * could panic during 'reboot -f' as the underlying device got already
 742          * disabled.
 743          */
 744         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 745                 panic("EXT4-fs (device %s): panic forced after error\n",
 746                         sb->s_id);
 747         }
 748
 749         if (sb_rdonly(sb) || continue_fs)
 750                 return;
 751
 752         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 753         /*
 754          * Make sure updated value of ->s_mount_flags will be visible before
 755          * ->s_flags update
 756          */
 757         smp_wmb();
 758         sb->s_flags |= SB_RDONLY;
 759 }
 760
 761 static void update_super_work(struct work_struct *work)
 762 {
 763         struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
 764                                                 s_sb_upd_work);
 765         journal_t *journal = sbi->s_journal;
 766         handle_t *handle;
 767
 768         /*
 769          * If the journal is still running, we have to write out superblock
 770          * through the journal to avoid collisions of other journalled sb
 771          * updates.
 772          *
 773          * We use directly jbd2 functions here to avoid recursing back into
 774          * ext4 error handling code during handling of previous errors.
 775          */
 776         if (!sb_rdonly(sbi->s_sb) && journal) {
 777                 struct buffer_head *sbh = sbi->s_sbh;
 778                 bool call_notify_err = false;
 779
 780                 handle = jbd2_journal_start(journal, 1);
 781                 if (IS_ERR(handle))
 782                         goto write_directly;
 783                 if (jbd2_journal_get_write_access(handle, sbh)) {
 784                         jbd2_journal_stop(handle);
 785                         goto write_directly;
 786                 }
 787
 788                 if (sbi->s_add_error_count > 0)
 789                         call_notify_err = true;
 790
 791                 ext4_update_super(sbi->s_sb);
 792                 if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
 793                         ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
 794                                  "superblock detected");
 795                         clear_buffer_write_io_error(sbh);
 796                         set_buffer_uptodate(sbh);
 797                 }
 798
 799                 if (jbd2_journal_dirty_metadata(handle, sbh)) {
 800                         jbd2_journal_stop(handle);
 801                         goto write_directly;
 802                 }
 803                 jbd2_journal_stop(handle);
 804
 805                 if (call_notify_err)
 806                         ext4_notify_error_sysfs(sbi);
 807
 808                 return;
 809         }
 810 write_directly:
 811         /*
 812          * Write through journal failed. Write sb directly to get error info
 813          * out and hope for the best.
 814          */
 815         ext4_commit_super(sbi->s_sb);
 816         ext4_notify_error_sysfs(sbi);
 817 }
 818
 819 #define ext4_error_ratelimit(sb)                                        \
 820                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 821                              "EXT4-fs error")
 822
 823 void __ext4_error(struct super_block *sb, const char *function,
 824                   unsigned int line, bool force_ro, int error, __u64 block,
 825                   const char *fmt, ...)
 826 {
 827         struct va_format vaf;
 828         va_list args;
 829
 830         if (unlikely(ext4_forced_shutdown(sb)))
 831                 return;
 832
 833         trace_ext4_error(sb, function, line);
 834         if (ext4_error_ratelimit(sb)) {
 835                 va_start(args, fmt);
 836                 vaf.fmt = fmt;
 837                 vaf.va = &args;
 838                 printk(KERN_CRIT
 839                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 840                        sb->s_id, function, line, current->comm, &vaf);
 841                 va_end(args);
 842         }
 843         fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
 844
 845         ext4_handle_error(sb, force_ro, error, 0, block, function, line);
 846 }
 847
 848 void __ext4_error_inode(struct inode *inode, const char *function,
 849                         unsigned int line, ext4_fsblk_t block, int error,
 850                         const char *fmt, ...)
 851 {
 852         va_list args;
 853         struct va_format vaf;
 854
 855         if (unlikely(ext4_forced_shutdown(inode->i_sb)))
 856                 return;
 857
 858         trace_ext4_error(inode->i_sb, function, line);
 859         if (ext4_error_ratelimit(inode->i_sb)) {
 860                 va_start(args, fmt);
 861                 vaf.fmt = fmt;
 862                 vaf.va = &args;
 863                 if (block)
 864                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 865                                "inode #%lu: block %llu: comm %s: %pV\n",
 866                                inode->i_sb->s_id, function, line, inode->i_ino,
 867                                block, current->comm, &vaf);
 868                 else
 869                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 870                                "inode #%lu: comm %s: %pV\n",
 871                                inode->i_sb->s_id, function, line, inode->i_ino,
 872                                current->comm, &vaf);
 873                 va_end(args);
 874         }
 875         fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
 876
 877         ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
 878                           function, line);
 879 }
 880
 881 void __ext4_error_file(struct file *file, const char *function,
 882                        unsigned int line, ext4_fsblk_t block,
 883                        const char *fmt, ...)
 884 {
 885         va_list args;
 886         struct va_format vaf;
 887         struct inode *inode = file_inode(file);
 888         char pathname[80], *path;
 889
 890         if (unlikely(ext4_forced_shutdown(inode->i_sb)))
 891                 return;
 892
 893         trace_ext4_error(inode->i_sb, function, line);
 894         if (ext4_error_ratelimit(inode->i_sb)) {
 895                 path = file_path(file, pathname, sizeof(pathname));
 896                 if (IS_ERR(path))
 897                         path = "(unknown)";
 898                 va_start(args, fmt);
 899                 vaf.fmt = fmt;
 900                 vaf.va = &args;
 901                 if (block)
 902                         printk(KERN_CRIT
 903                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 904                                "block %llu: comm %s: path %s: %pV\n",
 905                                inode->i_sb->s_id, function, line, inode->i_ino,
 906                                block, current->comm, path, &vaf);
 907                 else
 908                         printk(KERN_CRIT
 909                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 910                                "comm %s: path %s: %pV\n",
 911                                inode->i_sb->s_id, function, line, inode->i_ino,
 912                                current->comm, path, &vaf);
 913                 va_end(args);
 914         }
 915         fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
 916
 917         ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
 918                           function, line);
 919 }
 920
 921 const char *ext4_decode_error(struct super_block *sb, int errno,
 922                               char nbuf[16])
 923 {
 924         char *errstr = NULL;
 925
 926         switch (errno) {
 927         case -EFSCORRUPTED:
 928                 errstr = "Corrupt filesystem";
 929                 break;
 930         case -EFSBADCRC:
 931                 errstr = "Filesystem failed CRC";
 932                 break;
 933         case -EIO:
 934                 errstr = "IO failure";
 935                 break;
 936         case -ENOMEM:
 937                 errstr = "Out of memory";
 938                 break;
 939         case -EROFS:
 940                 if (!sb || (EXT4_SB(sb)->s_journal &&
 941                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 942                         errstr = "Journal has aborted";
 943                 else
 944                         errstr = "Readonly filesystem";
 945                 break;
 946         default:
 947                 /* If the caller passed in an extra buffer for unknown
 948                  * errors, textualise them now.  Else we just return
 949                  * NULL. */
 950                 if (nbuf) {
 951                         /* Check for truncated error codes... */
 952                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 953                                 errstr = nbuf;
 954                 }
 955                 break;
 956         }
 957
 958         return errstr;
 959 }
 960
 961 /* __ext4_std_error decodes expected errors from journaling functions
 962  * automatically and invokes the appropriate error response.  */
 963
 964 void __ext4_std_error(struct super_block *sb, const char *function,
 965                       unsigned int line, int errno)
 966 {
 967         char nbuf[16];
 968         const char *errstr;
 969
 970         if (unlikely(ext4_forced_shutdown(sb)))
 971                 return;
 972
 973         /* Special case: if the error is EROFS, and we're not already
 974          * inside a transaction, then there's really no point in logging
 975          * an error. */
 976         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 977                 return;
 978
 979         if (ext4_error_ratelimit(sb)) {
 980                 errstr = ext4_decode_error(sb, errno, nbuf);
 981                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 982                        sb->s_id, function, line, errstr);
 983         }
 984         fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
 985
 986         ext4_handle_error(sb, false, -errno, 0, 0, function, line);
 987 }
 988
 989 void __ext4_msg(struct super_block *sb,
 990                 const char *prefix, const char *fmt, ...)
 991 {
 992         struct va_format vaf;
 993         va_list args;
 994
 995         if (sb) {
 996                 atomic_inc(&EXT4_SB(sb)->s_msg_count);
 997                 if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state),
 998                                   "EXT4-fs"))
 999                         return;
1000         }
1001
1002         va_start(args, fmt);
1003         vaf.fmt = fmt;
1004         vaf.va = &args;
1005         if (sb)
1006                 printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
1007         else
1008                 printk("%sEXT4-fs: %pV\n", prefix, &vaf);
1009         va_end(args);
1010 }
1011
1012 static int ext4_warning_ratelimit(struct super_block *sb)
1013 {
1014         atomic_inc(&EXT4_SB(sb)->s_warning_count);
1015         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
1016                             "EXT4-fs warning");
1017 }
1018
1019 void __ext4_warning(struct super_block *sb, const char *function,
1020                     unsigned int line, const char *fmt, ...)
1021 {
1022         struct va_format vaf;
1023         va_list args;
1024
1025         if (!ext4_warning_ratelimit(sb))
1026                 return;
1027
1028         va_start(args, fmt);
1029         vaf.fmt = fmt;
1030         vaf.va = &args;
1031         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
1032                sb->s_id, function, line, &vaf);
1033         va_end(args);
1034 }
1035
1036 void __ext4_warning_inode(const struct inode *inode, const char *function,
1037                           unsigned int line, const char *fmt, ...)
1038 {
1039         struct va_format vaf;
1040         va_list args;
1041
1042         if (!ext4_warning_ratelimit(inode->i_sb))
1043                 return;
1044
1045         va_start(args, fmt);
1046         vaf.fmt = fmt;
1047         vaf.va = &args;
1048         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
1049                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
1050                function, line, inode->i_ino, current->comm, &vaf);
1051         va_end(args);
1052 }
1053
1054 void __ext4_grp_locked_error(const char *function, unsigned int line,
1055                              struct super_block *sb, ext4_group_t grp,
1056                              unsigned long ino, ext4_fsblk_t block,
1057                              const char *fmt, ...)
1058 __releases(bitlock)
1059 __acquires(bitlock)
1060 {
1061         struct va_format vaf;
1062         va_list args;
1063
1064         if (unlikely(ext4_forced_shutdown(sb)))
1065                 return;
1066
1067         trace_ext4_error(sb, function, line);
1068         if (ext4_error_ratelimit(sb)) {
1069                 va_start(args, fmt);
1070                 vaf.fmt = fmt;
1071                 vaf.va = &args;
1072                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1073                        sb->s_id, function, line, grp);
1074                 if (ino)
1075                         printk(KERN_CONT "inode %lu: ", ino);
1076                 if (block)
1077                         printk(KERN_CONT "block %llu:",
1078                                (unsigned long long) block);
1079                 printk(KERN_CONT "%pV\n", &vaf);
1080                 va_end(args);
1081         }
1082
1083         if (test_opt(sb, ERRORS_CONT)) {
1084                 if (test_opt(sb, WARN_ON_ERROR))
1085                         WARN_ON_ONCE(1);
1086                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
1087                 if (!bdev_read_only(sb->s_bdev)) {
1088                         save_error_info(sb, EFSCORRUPTED, ino, block, function,
1089                                         line);
1090                         schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
1091                 }
1092                 return;
1093         }
1094         ext4_unlock_group(sb, grp);
1095         ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1096         /*
1097          * We only get here in the ERRORS_RO case; relocking the group
1098          * may be dangerous, but nothing bad will happen since the
1099          * filesystem will have already been marked read/only and the
1100          * journal has been aborted.  We return 1 as a hint to callers
1101          * who might what to use the return value from
1102          * ext4_grp_locked_error() to distinguish between the
1103          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1104          * aggressively from the ext4 function in question, with a
1105          * more appropriate error code.
1106          */
1107         ext4_lock_group(sb, grp);
1108         return;
1109 }
1110
1111 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1112                                      ext4_group_t group,
1113                                      unsigned int flags)
1114 {
1115         struct ext4_sb_info *sbi = EXT4_SB(sb);
1116         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1117         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1118         int ret;
1119
1120         if (!grp || !gdp)
1121                 return;
1122         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1123                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1124                                             &grp->bb_state);
1125                 if (!ret)
1126                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1127                                            grp->bb_free);
1128         }
1129
1130         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1131                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1132                                             &grp->bb_state);
1133                 if (!ret && gdp) {
1134                         int count;
1135
1136                         count = ext4_free_inodes_count(sb, gdp);
1137                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1138                                            count);
1139                 }
1140         }
1141 }
1142
1143 void ext4_update_dynamic_rev(struct super_block *sb)
1144 {
1145         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1146
1147         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1148                 return;
1149
1150         ext4_warning(sb,
1151                      "updating to rev %d because of new feature flag, "
1152                      "running e2fsck is recommended",
1153                      EXT4_DYNAMIC_REV);
1154
1155         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1156         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1157         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1158         /* leave es->s_feature_*compat flags alone */
1159         /* es->s_uuid will be set by e2fsck if empty */
1160
1161         /*
1162          * The rest of the superblock fields should be zero, and if not it
1163          * means they are likely already in use, so leave them alone.  We
1164          * can leave it up to e2fsck to clean up any inconsistencies there.
1165          */
1166 }
1167
1168 static inline struct inode *orphan_list_entry(struct list_head *l)
1169 {
1170         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1171 }
1172
1173 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1174 {
1175         struct list_head *l;
1176
1177         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1178                  le32_to_cpu(sbi->s_es->s_last_orphan));
1179
1180         printk(KERN_ERR "sb_info orphan list:\n");
1181         list_for_each(l, &sbi->s_orphan) {
1182                 struct inode *inode = orphan_list_entry(l);
1183                 printk(KERN_ERR "  "
1184                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1185                        inode->i_sb->s_id, inode->i_ino, inode,
1186                        inode->i_mode, inode->i_nlink,
1187                        NEXT_ORPHAN(inode));
1188         }
1189 }
1190
1191 #ifdef CONFIG_QUOTA
1192 static int ext4_quota_off(struct super_block *sb, int type);
1193
1194 static inline void ext4_quotas_off(struct super_block *sb, int type)
1195 {
1196         BUG_ON(type > EXT4_MAXQUOTAS);
1197
1198         /* Use our quota_off function to clear inode flags etc. */
1199         for (type--; type >= 0; type--)
1200                 ext4_quota_off(sb, type);
1201 }
1202
1203 /*
1204  * This is a helper function which is used in the mount/remount
1205  * codepaths (which holds s_umount) to fetch the quota file name.
1206  */
1207 static inline char *get_qf_name(struct super_block *sb,
1208                                 struct ext4_sb_info *sbi,
1209                                 int type)
1210 {
1211         return rcu_dereference_protected(sbi->s_qf_names[type],
1212                                          lockdep_is_held(&sb->s_umount));
1213 }
1214 #else
1215 static inline void ext4_quotas_off(struct super_block *sb, int type)
1216 {
1217 }
1218 #endif
1219
1220 static int ext4_percpu_param_init(struct ext4_sb_info *sbi)
1221 {
1222         ext4_fsblk_t block;
1223         int err;
1224
1225         block = ext4_count_free_clusters(sbi->s_sb);
1226         ext4_free_blocks_count_set(sbi->s_es, EXT4_C2B(sbi, block));
1227         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
1228                                   GFP_KERNEL);
1229         if (!err) {
1230                 unsigned long freei = ext4_count_free_inodes(sbi->s_sb);
1231                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
1232                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
1233                                           GFP_KERNEL);
1234         }
1235         if (!err)
1236                 err = percpu_counter_init(&sbi->s_dirs_counter,
1237                                           ext4_count_dirs(sbi->s_sb), GFP_KERNEL);
1238         if (!err)
1239                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
1240                                           GFP_KERNEL);
1241         if (!err)
1242                 err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
1243                                           GFP_KERNEL);
1244         if (!err)
1245                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
1246
1247         if (err)
1248                 ext4_msg(sbi->s_sb, KERN_ERR, "insufficient memory");
1249
1250         return err;
1251 }
1252
1253 static void ext4_percpu_param_destroy(struct ext4_sb_info *sbi)
1254 {
1255         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1256         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1257         percpu_counter_destroy(&sbi->s_dirs_counter);
1258         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1259         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1260         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1261 }
1262
1263 static void ext4_group_desc_free(struct ext4_sb_info *sbi)
1264 {
1265         struct buffer_head **group_desc;
1266         int i;
1267
1268         rcu_read_lock();
1269         group_desc = rcu_dereference(sbi->s_group_desc);
1270         for (i = 0; i < sbi->s_gdb_count; i++)
1271                 brelse(group_desc[i]);
1272         kvfree(group_desc);
1273         rcu_read_unlock();
1274 }
1275
1276 static void ext4_flex_groups_free(struct ext4_sb_info *sbi)
1277 {
1278         struct flex_groups **flex_groups;
1279         int i;
1280
1281         rcu_read_lock();
1282         flex_groups = rcu_dereference(sbi->s_flex_groups);
1283         if (flex_groups) {
1284                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1285                         kvfree(flex_groups[i]);
1286                 kvfree(flex_groups);
1287         }
1288         rcu_read_unlock();
1289 }
1290
1291 static void ext4_put_super(struct super_block *sb)
1292 {
1293         struct ext4_sb_info *sbi = EXT4_SB(sb);
1294         struct ext4_super_block *es = sbi->s_es;
1295         int aborted = 0;
1296         int err;
1297
1298         /*
1299          * Unregister sysfs before destroying jbd2 journal.
1300          * Since we could still access attr_journal_task attribute via sysfs
1301          * path which could have sbi->s_journal->j_task as NULL
1302          * Unregister sysfs before flush sbi->s_sb_upd_work.
1303          * Since user may read /proc/fs/ext4/xx/mb_groups during umount, If
1304          * read metadata verify failed then will queue error work.
1305          * update_super_work will call start_this_handle may trigger
1306          * BUG_ON.
1307          */
1308         ext4_unregister_sysfs(sb);
1309
1310         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs unmount"))
1311                 ext4_msg(sb, KERN_INFO, "unmounting filesystem %pU.",
1312                          &sb->s_uuid);
1313
1314         ext4_unregister_li_request(sb);
1315         ext4_quotas_off(sb, EXT4_MAXQUOTAS);
1316
1317         flush_work(&sbi->s_sb_upd_work);
1318         destroy_workqueue(sbi->rsv_conversion_wq);
1319         ext4_release_orphan_info(sb);
1320
1321         if (sbi->s_journal) {
1322                 aborted = is_journal_aborted(sbi->s_journal);
1323                 err = jbd2_journal_destroy(sbi->s_journal);
1324                 sbi->s_journal = NULL;
1325                 if ((err < 0) && !aborted) {
1326                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1327                 }
1328         }
1329
1330         ext4_es_unregister_shrinker(sbi);
1331         timer_shutdown_sync(&sbi->s_err_report);
1332         ext4_release_system_zone(sb);
1333         ext4_mb_release(sb);
1334         ext4_ext_release(sb);
1335
1336         if (!sb_rdonly(sb) && !aborted) {
1337                 ext4_clear_feature_journal_needs_recovery(sb);
1338                 ext4_clear_feature_orphan_present(sb);
1339                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1340         }
1341         if (!sb_rdonly(sb))
1342                 ext4_commit_super(sb);
1343
1344         ext4_group_desc_free(sbi);
1345         ext4_flex_groups_free(sbi);
1346         ext4_percpu_param_destroy(sbi);
1347 #ifdef CONFIG_QUOTA
1348         for (int i = 0; i < EXT4_MAXQUOTAS; i++)
1349                 kfree(get_qf_name(sb, sbi, i));
1350 #endif
1351
1352         /* Debugging code just in case the in-memory inode orphan list
1353          * isn't empty.  The on-disk one can be non-empty if we've
1354          * detected an error and taken the fs readonly, but the
1355          * in-memory list had better be clean by this point. */
1356         if (!list_empty(&sbi->s_orphan))
1357                 dump_orphan_list(sb, sbi);
1358         ASSERT(list_empty(&sbi->s_orphan));
1359
1360         sync_blockdev(sb->s_bdev);
1361         invalidate_bdev(sb->s_bdev);
1362         if (sbi->s_journal_bdev_handle) {
1363                 /*
1364                  * Invalidate the journal device's buffers.  We don't want them
1365                  * floating about in memory - the physical journal device may
1366                  * hotswapped, and it breaks the `ro-after' testing code.
1367                  */
1368                 sync_blockdev(sbi->s_journal_bdev_handle->bdev);
1369                 invalidate_bdev(sbi->s_journal_bdev_handle->bdev);
1370         }
1371
1372         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1373         sbi->s_ea_inode_cache = NULL;
1374
1375         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1376         sbi->s_ea_block_cache = NULL;
1377
1378         ext4_stop_mmpd(sbi);
1379
1380         brelse(sbi->s_sbh);
1381         sb->s_fs_info = NULL;
1382         /*
1383          * Now that we are completely done shutting down the
1384          * superblock, we need to actually destroy the kobject.
1385          */
1386         kobject_put(&sbi->s_kobj);
1387         wait_for_completion(&sbi->s_kobj_unregister);
1388         if (sbi->s_chksum_driver)
1389                 crypto_free_shash(sbi->s_chksum_driver);
1390         kfree(sbi->s_blockgroup_lock);
1391         fs_put_dax(sbi->s_daxdev, NULL);
1392         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1393 #if IS_ENABLED(CONFIG_UNICODE)
1394         utf8_unload(sb->s_encoding);
1395 #endif
1396         kfree(sbi);
1397 }
1398
1399 static struct kmem_cache *ext4_inode_cachep;
1400
1401 /*
1402  * Called inside transaction, so use GFP_NOFS
1403  */
1404 static struct inode *ext4_alloc_inode(struct super_block *sb)
1405 {
1406         struct ext4_inode_info *ei;
1407
1408         ei = alloc_inode_sb(sb, ext4_inode_cachep, GFP_NOFS);
1409         if (!ei)
1410                 return NULL;
1411
1412         inode_set_iversion(&ei->vfs_inode, 1);
1413         ei->i_flags = 0;
1414         spin_lock_init(&ei->i_raw_lock);
1415         ei->i_prealloc_node = RB_ROOT;
1416         atomic_set(&ei->i_prealloc_active, 0);
1417         rwlock_init(&ei->i_prealloc_lock);
1418         ext4_es_init_tree(&ei->i_es_tree);
1419         rwlock_init(&ei->i_es_lock);
1420         INIT_LIST_HEAD(&ei->i_es_list);
1421         ei->i_es_all_nr = 0;
1422         ei->i_es_shk_nr = 0;
1423         ei->i_es_shrink_lblk = 0;
1424         ei->i_reserved_data_blocks = 0;
1425         spin_lock_init(&(ei->i_block_reservation_lock));
1426         ext4_init_pending_tree(&ei->i_pending_tree);
1427 #ifdef CONFIG_QUOTA
1428         ei->i_reserved_quota = 0;
1429         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1430 #endif
1431         ei->jinode = NULL;
1432         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1433         spin_lock_init(&ei->i_completed_io_lock);
1434         ei->i_sync_tid = 0;
1435         ei->i_datasync_tid = 0;
1436         atomic_set(&ei->i_unwritten, 0);
1437         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1438         ext4_fc_init_inode(&ei->vfs_inode);
1439         mutex_init(&ei->i_fc_lock);
1440         return &ei->vfs_inode;
1441 }
1442
1443 static int ext4_drop_inode(struct inode *inode)
1444 {
1445         int drop = generic_drop_inode(inode);
1446
1447         if (!drop)
1448                 drop = fscrypt_drop_inode(inode);
1449
1450         trace_ext4_drop_inode(inode, drop);
1451         return drop;
1452 }
1453
1454 static void ext4_free_in_core_inode(struct inode *inode)
1455 {
1456         fscrypt_free_inode(inode);
1457         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1458                 pr_warn("%s: inode %ld still in fc list",
1459                         __func__, inode->i_ino);
1460         }
1461         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1462 }
1463
1464 static void ext4_destroy_inode(struct inode *inode)
1465 {
1466         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1467                 ext4_msg(inode->i_sb, KERN_ERR,
1468                          "Inode %lu (%p): orphan list check failed!",
1469                          inode->i_ino, EXT4_I(inode));
1470                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1471                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1472                                 true);
1473                 dump_stack();
1474         }
1475
1476         if (EXT4_I(inode)->i_reserved_data_blocks)
1477                 ext4_msg(inode->i_sb, KERN_ERR,
1478                          "Inode %lu (%p): i_reserved_data_blocks (%u) not cleared!",
1479                          inode->i_ino, EXT4_I(inode),
1480                          EXT4_I(inode)->i_reserved_data_blocks);
1481 }
1482
1483 static void ext4_shutdown(struct super_block *sb)
1484 {
1485        ext4_force_shutdown(sb, EXT4_GOING_FLAGS_NOLOGFLUSH);
1486 }
1487
1488 static void init_once(void *foo)
1489 {
1490         struct ext4_inode_info *ei = foo;
1491
1492         INIT_LIST_HEAD(&ei->i_orphan);
1493         init_rwsem(&ei->xattr_sem);
1494         init_rwsem(&ei->i_data_sem);
1495         inode_init_once(&ei->vfs_inode);
1496         ext4_fc_init_inode(&ei->vfs_inode);
1497 }
1498
1499 static int __init init_inodecache(void)
1500 {
1501         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1502                                 sizeof(struct ext4_inode_info), 0,
1503                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1504                                         SLAB_ACCOUNT),
1505                                 offsetof(struct ext4_inode_info, i_data),
1506                                 sizeof_field(struct ext4_inode_info, i_data),
1507                                 init_once);
1508         if (ext4_inode_cachep == NULL)
1509                 return -ENOMEM;
1510         return 0;
1511 }
1512
1513 static void destroy_inodecache(void)
1514 {
1515         /*
1516          * Make sure all delayed rcu free inodes are flushed before we
1517          * destroy cache.
1518          */
1519         rcu_barrier();
1520         kmem_cache_destroy(ext4_inode_cachep);
1521 }
1522
1523 void ext4_clear_inode(struct inode *inode)
1524 {
1525         ext4_fc_del(inode);
1526         invalidate_inode_buffers(inode);
1527         clear_inode(inode);
1528         ext4_discard_preallocations(inode, 0);
1529         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1530         dquot_drop(inode);
1531         if (EXT4_I(inode)->jinode) {
1532                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1533                                                EXT4_I(inode)->jinode);
1534                 jbd2_free_inode(EXT4_I(inode)->jinode);
1535                 EXT4_I(inode)->jinode = NULL;
1536         }
1537         fscrypt_put_encryption_info(inode);
1538         fsverity_cleanup_inode(inode);
1539 }
1540
1541 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1542                                         u64 ino, u32 generation)
1543 {
1544         struct inode *inode;
1545
1546         /*
1547          * Currently we don't know the generation for parent directory, so
1548          * a generation of 0 means "accept any"
1549          */
1550         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1551         if (IS_ERR(inode))
1552                 return ERR_CAST(inode);
1553         if (generation && inode->i_generation != generation) {
1554                 iput(inode);
1555                 return ERR_PTR(-ESTALE);
1556         }
1557
1558         return inode;
1559 }
1560
1561 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1562                                         int fh_len, int fh_type)
1563 {
1564         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1565                                     ext4_nfs_get_inode);
1566 }
1567
1568 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1569                                         int fh_len, int fh_type)
1570 {
1571         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1572                                     ext4_nfs_get_inode);
1573 }
1574
1575 static int ext4_nfs_commit_metadata(struct inode *inode)
1576 {
1577         struct writeback_control wbc = {
1578                 .sync_mode = WB_SYNC_ALL
1579         };
1580
1581         trace_ext4_nfs_commit_metadata(inode);
1582         return ext4_write_inode(inode, &wbc);
1583 }
1584
1585 #ifdef CONFIG_QUOTA
1586 static const char * const quotatypes[] = INITQFNAMES;
1587 #define QTYPE2NAME(t) (quotatypes[t])
1588
1589 static int ext4_write_dquot(struct dquot *dquot);
1590 static int ext4_acquire_dquot(struct dquot *dquot);
1591 static int ext4_release_dquot(struct dquot *dquot);
1592 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1593 static int ext4_write_info(struct super_block *sb, int type);
1594 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1595                          const struct path *path);
1596 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1597                                size_t len, loff_t off);
1598 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1599                                 const char *data, size_t len, loff_t off);
1600 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1601                              unsigned int flags);
1602
1603 static struct dquot **ext4_get_dquots(struct inode *inode)
1604 {
1605         return EXT4_I(inode)->i_dquot;
1606 }
1607
1608 static const struct dquot_operations ext4_quota_operations = {
1609         .get_reserved_space     = ext4_get_reserved_space,
1610         .write_dquot            = ext4_write_dquot,
1611         .acquire_dquot          = ext4_acquire_dquot,
1612         .release_dquot          = ext4_release_dquot,
1613         .mark_dirty             = ext4_mark_dquot_dirty,
1614         .write_info             = ext4_write_info,
1615         .alloc_dquot            = dquot_alloc,
1616         .destroy_dquot          = dquot_destroy,
1617         .get_projid             = ext4_get_projid,
1618         .get_inode_usage        = ext4_get_inode_usage,
1619         .get_next_id            = dquot_get_next_id,
1620 };
1621
1622 static const struct quotactl_ops ext4_qctl_operations = {
1623         .quota_on       = ext4_quota_on,
1624         .quota_off      = ext4_quota_off,
1625         .quota_sync     = dquot_quota_sync,
1626         .get_state      = dquot_get_state,
1627         .set_info       = dquot_set_dqinfo,
1628         .get_dqblk      = dquot_get_dqblk,
1629         .set_dqblk      = dquot_set_dqblk,
1630         .get_nextdqblk  = dquot_get_next_dqblk,
1631 };
1632 #endif
1633
1634 static const struct super_operations ext4_sops = {
1635         .alloc_inode    = ext4_alloc_inode,
1636         .free_inode     = ext4_free_in_core_inode,
1637         .destroy_inode  = ext4_destroy_inode,
1638         .write_inode    = ext4_write_inode,
1639         .dirty_inode    = ext4_dirty_inode,
1640         .drop_inode     = ext4_drop_inode,
1641         .evict_inode    = ext4_evict_inode,
1642         .put_super      = ext4_put_super,
1643         .sync_fs        = ext4_sync_fs,
1644         .freeze_fs      = ext4_freeze,
1645         .unfreeze_fs    = ext4_unfreeze,
1646         .statfs         = ext4_statfs,
1647         .show_options   = ext4_show_options,
1648         .shutdown       = ext4_shutdown,
1649 #ifdef CONFIG_QUOTA
1650         .quota_read     = ext4_quota_read,
1651         .quota_write    = ext4_quota_write,
1652         .get_dquots     = ext4_get_dquots,
1653 #endif
1654 };
1655
1656 static const struct export_operations ext4_export_ops = {
1657         .encode_fh = generic_encode_ino32_fh,
1658         .fh_to_dentry = ext4_fh_to_dentry,
1659         .fh_to_parent = ext4_fh_to_parent,
1660         .get_parent = ext4_get_parent,
1661         .commit_metadata = ext4_nfs_commit_metadata,
1662 };
1663
1664 enum {
1665         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1666         Opt_resgid, Opt_resuid, Opt_sb,
1667         Opt_nouid32, Opt_debug, Opt_removed,
1668         Opt_user_xattr, Opt_acl,
1669         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1670         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1671         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1672         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1673         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1674         Opt_inlinecrypt,
1675         Opt_usrjquota, Opt_grpjquota, Opt_quota,
1676         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1677         Opt_usrquota, Opt_grpquota, Opt_prjquota,
1678         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1679         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1680         Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
1681         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1682         Opt_inode_readahead_blks, Opt_journal_ioprio,
1683         Opt_dioread_nolock, Opt_dioread_lock,
1684         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1685         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1686         Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1687         Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
1688 #ifdef CONFIG_EXT4_DEBUG
1689         Opt_fc_debug_max_replay, Opt_fc_debug_force
1690 #endif
1691 };
1692
1693 static const struct constant_table ext4_param_errors[] = {
1694         {"continue",    EXT4_MOUNT_ERRORS_CONT},
1695         {"panic",       EXT4_MOUNT_ERRORS_PANIC},
1696         {"remount-ro",  EXT4_MOUNT_ERRORS_RO},
1697         {}
1698 };
1699
1700 static const struct constant_table ext4_param_data[] = {
1701         {"journal",     EXT4_MOUNT_JOURNAL_DATA},
1702         {"ordered",     EXT4_MOUNT_ORDERED_DATA},
1703         {"writeback",   EXT4_MOUNT_WRITEBACK_DATA},
1704         {}
1705 };
1706
1707 static const struct constant_table ext4_param_data_err[] = {
1708         {"abort",       Opt_data_err_abort},
1709         {"ignore",      Opt_data_err_ignore},
1710         {}
1711 };
1712
1713 static const struct constant_table ext4_param_jqfmt[] = {
1714         {"vfsold",      QFMT_VFS_OLD},
1715         {"vfsv0",       QFMT_VFS_V0},
1716         {"vfsv1",       QFMT_VFS_V1},
1717         {}
1718 };
1719
1720 static const struct constant_table ext4_param_dax[] = {
1721         {"always",      Opt_dax_always},
1722         {"inode",       Opt_dax_inode},
1723         {"never",       Opt_dax_never},
1724         {}
1725 };
1726
1727 /* String parameter that allows empty argument */
1728 #define fsparam_string_empty(NAME, OPT) \
1729         __fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
1730
1731 /*
1732  * Mount option specification
1733  * We don't use fsparam_flag_no because of the way we set the
1734  * options and the way we show them in _ext4_show_options(). To
1735  * keep the changes to a minimum, let's keep the negative options
1736  * separate for now.
1737  */
1738 static const struct fs_parameter_spec ext4_param_specs[] = {
1739         fsparam_flag    ("bsddf",               Opt_bsd_df),
1740         fsparam_flag    ("minixdf",             Opt_minix_df),
1741         fsparam_flag    ("grpid",               Opt_grpid),
1742         fsparam_flag    ("bsdgroups",           Opt_grpid),
1743         fsparam_flag    ("nogrpid",             Opt_nogrpid),
1744         fsparam_flag    ("sysvgroups",          Opt_nogrpid),
1745         fsparam_u32     ("resgid",              Opt_resgid),
1746         fsparam_u32     ("resuid",              Opt_resuid),
1747         fsparam_u32     ("sb",                  Opt_sb),
1748         fsparam_enum    ("errors",              Opt_errors, ext4_param_errors),
1749         fsparam_flag    ("nouid32",             Opt_nouid32),
1750         fsparam_flag    ("debug",               Opt_debug),
1751         fsparam_flag    ("oldalloc",            Opt_removed),
1752         fsparam_flag    ("orlov",               Opt_removed),
1753         fsparam_flag    ("user_xattr",          Opt_user_xattr),
1754         fsparam_flag    ("acl",                 Opt_acl),
1755         fsparam_flag    ("norecovery",          Opt_noload),
1756         fsparam_flag    ("noload",              Opt_noload),
1757         fsparam_flag    ("bh",                  Opt_removed),
1758         fsparam_flag    ("nobh",                Opt_removed),
1759         fsparam_u32     ("commit",              Opt_commit),
1760         fsparam_u32     ("min_batch_time",      Opt_min_batch_time),
1761         fsparam_u32     ("max_batch_time",      Opt_max_batch_time),
1762         fsparam_u32     ("journal_dev",         Opt_journal_dev),
1763         fsparam_bdev    ("journal_path",        Opt_journal_path),
1764         fsparam_flag    ("journal_checksum",    Opt_journal_checksum),
1765         fsparam_flag    ("nojournal_checksum",  Opt_nojournal_checksum),
1766         fsparam_flag    ("journal_async_commit",Opt_journal_async_commit),
1767         fsparam_flag    ("abort",               Opt_abort),
1768         fsparam_enum    ("data",                Opt_data, ext4_param_data),
1769         fsparam_enum    ("data_err",            Opt_data_err,
1770                                                 ext4_param_data_err),
1771         fsparam_string_empty
1772                         ("usrjquota",           Opt_usrjquota),
1773         fsparam_string_empty
1774                         ("grpjquota",           Opt_grpjquota),
1775         fsparam_enum    ("jqfmt",               Opt_jqfmt, ext4_param_jqfmt),
1776         fsparam_flag    ("grpquota",            Opt_grpquota),
1777         fsparam_flag    ("quota",               Opt_quota),
1778         fsparam_flag    ("noquota",             Opt_noquota),
1779         fsparam_flag    ("usrquota",            Opt_usrquota),
1780         fsparam_flag    ("prjquota",            Opt_prjquota),
1781         fsparam_flag    ("barrier",             Opt_barrier),
1782         fsparam_u32     ("barrier",             Opt_barrier),
1783         fsparam_flag    ("nobarrier",           Opt_nobarrier),
1784         fsparam_flag    ("i_version",           Opt_removed),
1785         fsparam_flag    ("dax",                 Opt_dax),
1786         fsparam_enum    ("dax",                 Opt_dax_type, ext4_param_dax),
1787         fsparam_u32     ("stripe",              Opt_stripe),
1788         fsparam_flag    ("delalloc",            Opt_delalloc),
1789         fsparam_flag    ("nodelalloc",          Opt_nodelalloc),
1790         fsparam_flag    ("warn_on_error",       Opt_warn_on_error),
1791         fsparam_flag    ("nowarn_on_error",     Opt_nowarn_on_error),
1792         fsparam_u32     ("debug_want_extra_isize",
1793                                                 Opt_debug_want_extra_isize),
1794         fsparam_flag    ("mblk_io_submit",      Opt_removed),
1795         fsparam_flag    ("nomblk_io_submit",    Opt_removed),
1796         fsparam_flag    ("block_validity",      Opt_block_validity),
1797         fsparam_flag    ("noblock_validity",    Opt_noblock_validity),
1798         fsparam_u32     ("inode_readahead_blks",
1799                                                 Opt_inode_readahead_blks),
1800         fsparam_u32     ("journal_ioprio",      Opt_journal_ioprio),
1801         fsparam_u32     ("auto_da_alloc",       Opt_auto_da_alloc),
1802         fsparam_flag    ("auto_da_alloc",       Opt_auto_da_alloc),
1803         fsparam_flag    ("noauto_da_alloc",     Opt_noauto_da_alloc),
1804         fsparam_flag    ("dioread_nolock",      Opt_dioread_nolock),
1805         fsparam_flag    ("nodioread_nolock",    Opt_dioread_lock),
1806         fsparam_flag    ("dioread_lock",        Opt_dioread_lock),
1807         fsparam_flag    ("discard",             Opt_discard),
1808         fsparam_flag    ("nodiscard",           Opt_nodiscard),
1809         fsparam_u32     ("init_itable",         Opt_init_itable),
1810         fsparam_flag    ("init_itable",         Opt_init_itable),
1811         fsparam_flag    ("noinit_itable",       Opt_noinit_itable),
1812 #ifdef CONFIG_EXT4_DEBUG
1813         fsparam_flag    ("fc_debug_force",      Opt_fc_debug_force),
1814         fsparam_u32     ("fc_debug_max_replay", Opt_fc_debug_max_replay),
1815 #endif
1816         fsparam_u32     ("max_dir_size_kb",     Opt_max_dir_size_kb),
1817         fsparam_flag    ("test_dummy_encryption",
1818                                                 Opt_test_dummy_encryption),
1819         fsparam_string  ("test_dummy_encryption",
1820                                                 Opt_test_dummy_encryption),
1821         fsparam_flag    ("inlinecrypt",         Opt_inlinecrypt),
1822         fsparam_flag    ("nombcache",           Opt_nombcache),
1823         fsparam_flag    ("no_mbcache",          Opt_nombcache), /* for backward compatibility */
1824         fsparam_flag    ("prefetch_block_bitmaps",
1825                                                 Opt_removed),
1826         fsparam_flag    ("no_prefetch_block_bitmaps",
1827                                                 Opt_no_prefetch_block_bitmaps),
1828         fsparam_s32     ("mb_optimize_scan",    Opt_mb_optimize_scan),
1829         fsparam_string  ("check",               Opt_removed),   /* mount option from ext2/3 */
1830         fsparam_flag    ("nocheck",             Opt_removed),   /* mount option from ext2/3 */
1831         fsparam_flag    ("reservation",         Opt_removed),   /* mount option from ext2/3 */
1832         fsparam_flag    ("noreservation",       Opt_removed),   /* mount option from ext2/3 */
1833         fsparam_u32     ("journal",             Opt_removed),   /* mount option from ext2/3 */
1834         {}
1835 };
1836
1837 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1838
1839 #define MOPT_SET        0x0001
1840 #define MOPT_CLEAR      0x0002
1841 #define MOPT_NOSUPPORT  0x0004
1842 #define MOPT_EXPLICIT   0x0008
1843 #ifdef CONFIG_QUOTA
1844 #define MOPT_Q          0
1845 #define MOPT_QFMT       0x0010
1846 #else
1847 #define MOPT_Q          MOPT_NOSUPPORT
1848 #define MOPT_QFMT       MOPT_NOSUPPORT
1849 #endif
1850 #define MOPT_NO_EXT2    0x0020
1851 #define MOPT_NO_EXT3    0x0040
1852 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1853 #define MOPT_SKIP       0x0080
1854 #define MOPT_2          0x0100
1855
1856 static const struct mount_opts {
1857         int     token;
1858         int     mount_opt;
1859         int     flags;
1860 } ext4_mount_opts[] = {
1861         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1862         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1863         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1864         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1865         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1866         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1867         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1868          MOPT_EXT4_ONLY | MOPT_SET},
1869         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1870          MOPT_EXT4_ONLY | MOPT_CLEAR},
1871         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1872         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1873         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1874          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1875         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1876          MOPT_EXT4_ONLY | MOPT_CLEAR},
1877         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1878         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1879         {Opt_commit, 0, MOPT_NO_EXT2},
1880         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1881          MOPT_EXT4_ONLY | MOPT_CLEAR},
1882         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1883          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1884         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1885                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1886          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1887         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1888         {Opt_data_err, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_NO_EXT2},
1889         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1890         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1891         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1892         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1893         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1894         {Opt_dax_type, 0, MOPT_EXT4_ONLY},
1895         {Opt_journal_dev, 0, MOPT_NO_EXT2},
1896         {Opt_journal_path, 0, MOPT_NO_EXT2},
1897         {Opt_journal_ioprio, 0, MOPT_NO_EXT2},
1898         {Opt_data, 0, MOPT_NO_EXT2},
1899         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1900 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1901         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1902 #else
1903         {Opt_acl, 0, MOPT_NOSUPPORT},
1904 #endif
1905         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1906         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1907         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1908         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1909                                                         MOPT_SET | MOPT_Q},
1910         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1911                                                         MOPT_SET | MOPT_Q},
1912         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1913                                                         MOPT_SET | MOPT_Q},
1914         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1915                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1916                                                         MOPT_CLEAR | MOPT_Q},
1917         {Opt_usrjquota, 0, MOPT_Q},
1918         {Opt_grpjquota, 0, MOPT_Q},
1919         {Opt_jqfmt, 0, MOPT_QFMT},
1920         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1921         {Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
1922          MOPT_SET},
1923 #ifdef CONFIG_EXT4_DEBUG
1924         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1925          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1926 #endif
1927         {Opt_abort, EXT4_MOUNT2_ABORT, MOPT_SET | MOPT_2},
1928         {Opt_err, 0, 0}
1929 };
1930
1931 #if IS_ENABLED(CONFIG_UNICODE)
1932 static const struct ext4_sb_encodings {
1933         __u16 magic;
1934         char *name;
1935         unsigned int version;
1936 } ext4_sb_encoding_map[] = {
1937         {EXT4_ENC_UTF8_12_1, "utf8", UNICODE_AGE(12, 1, 0)},
1938 };
1939
1940 static const struct ext4_sb_encodings *
1941 ext4_sb_read_encoding(const struct ext4_super_block *es)
1942 {
1943         __u16 magic = le16_to_cpu(es->s_encoding);
1944         int i;
1945
1946         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1947                 if (magic == ext4_sb_encoding_map[i].magic)
1948                         return &ext4_sb_encoding_map[i];
1949
1950         return NULL;
1951 }
1952 #endif
1953
1954 #define EXT4_SPEC_JQUOTA                        (1 <<  0)
1955 #define EXT4_SPEC_JQFMT                         (1 <<  1)
1956 #define EXT4_SPEC_DATAJ                         (1 <<  2)
1957 #define EXT4_SPEC_SB_BLOCK                      (1 <<  3)
1958 #define EXT4_SPEC_JOURNAL_DEV                   (1 <<  4)
1959 #define EXT4_SPEC_JOURNAL_IOPRIO                (1 <<  5)
1960 #define EXT4_SPEC_s_want_extra_isize            (1 <<  7)
1961 #define EXT4_SPEC_s_max_batch_time              (1 <<  8)
1962 #define EXT4_SPEC_s_min_batch_time              (1 <<  9)
1963 #define EXT4_SPEC_s_inode_readahead_blks        (1 << 10)
1964 #define EXT4_SPEC_s_li_wait_mult                (1 << 11)
1965 #define EXT4_SPEC_s_max_dir_size_kb             (1 << 12)
1966 #define EXT4_SPEC_s_stripe                      (1 << 13)
1967 #define EXT4_SPEC_s_resuid                      (1 << 14)
1968 #define EXT4_SPEC_s_resgid                      (1 << 15)
1969 #define EXT4_SPEC_s_commit_interval             (1 << 16)
1970 #define EXT4_SPEC_s_fc_debug_max_replay         (1 << 17)
1971 #define EXT4_SPEC_s_sb_block                    (1 << 18)
1972 #define EXT4_SPEC_mb_optimize_scan              (1 << 19)
1973
1974 struct ext4_fs_context {
1975         char            *s_qf_names[EXT4_MAXQUOTAS];
1976         struct fscrypt_dummy_policy dummy_enc_policy;
1977         int             s_jquota_fmt;   /* Format of quota to use */
1978 #ifdef CONFIG_EXT4_DEBUG
1979         int s_fc_debug_max_replay;
1980 #endif
1981         unsigned short  qname_spec;
1982         unsigned long   vals_s_flags;   /* Bits to set in s_flags */
1983         unsigned long   mask_s_flags;   /* Bits changed in s_flags */
1984         unsigned long   journal_devnum;
1985         unsigned long   s_commit_interval;
1986         unsigned long   s_stripe;
1987         unsigned int    s_inode_readahead_blks;
1988         unsigned int    s_want_extra_isize;
1989         unsigned int    s_li_wait_mult;
1990         unsigned int    s_max_dir_size_kb;
1991         unsigned int    journal_ioprio;
1992         unsigned int    vals_s_mount_opt;
1993         unsigned int    mask_s_mount_opt;
1994         unsigned int    vals_s_mount_opt2;
1995         unsigned int    mask_s_mount_opt2;
1996         unsigned int    opt_flags;      /* MOPT flags */
1997         unsigned int    spec;
1998         u32             s_max_batch_time;
1999         u32             s_min_batch_time;
2000         kuid_t          s_resuid;
2001         kgid_t          s_resgid;
2002         ext4_fsblk_t    s_sb_block;
2003 };
2004
2005 static void ext4_fc_free(struct fs_context *fc)
2006 {
2007         struct ext4_fs_context *ctx = fc->fs_private;
2008         int i;
2009
2010         if (!ctx)
2011                 return;
2012
2013         for (i = 0; i < EXT4_MAXQUOTAS; i++)
2014                 kfree(ctx->s_qf_names[i]);
2015
2016         fscrypt_free_dummy_policy(&ctx->dummy_enc_policy);
2017         kfree(ctx);
2018 }
2019
2020 int ext4_init_fs_context(struct fs_context *fc)
2021 {
2022         struct ext4_fs_context *ctx;
2023
2024         ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2025         if (!ctx)
2026                 return -ENOMEM;
2027
2028         fc->fs_private = ctx;
2029         fc->ops = &ext4_context_ops;
2030
2031         return 0;
2032 }
2033
2034 #ifdef CONFIG_QUOTA
2035 /*
2036  * Note the name of the specified quota file.
2037  */
2038 static int note_qf_name(struct fs_context *fc, int qtype,
2039                        struct fs_parameter *param)
2040 {
2041         struct ext4_fs_context *ctx = fc->fs_private;
2042         char *qname;
2043
2044         if (param->size < 1) {
2045                 ext4_msg(NULL, KERN_ERR, "Missing quota name");
2046                 return -EINVAL;
2047         }
2048         if (strchr(param->string, '/')) {
2049                 ext4_msg(NULL, KERN_ERR,
2050                          "quotafile must be on filesystem root");
2051                 return -EINVAL;
2052         }
2053         if (ctx->s_qf_names[qtype]) {
2054                 if (strcmp(ctx->s_qf_names[qtype], param->string) != 0) {
2055                         ext4_msg(NULL, KERN_ERR,
2056                                  "%s quota file already specified",
2057                                  QTYPE2NAME(qtype));
2058                         return -EINVAL;
2059                 }
2060                 return 0;
2061         }
2062
2063         qname = kmemdup_nul(param->string, param->size, GFP_KERNEL);
2064         if (!qname) {
2065                 ext4_msg(NULL, KERN_ERR,
2066                          "Not enough memory for storing quotafile name");
2067                 return -ENOMEM;
2068         }
2069         ctx->s_qf_names[qtype] = qname;
2070         ctx->qname_spec |= 1 << qtype;
2071         ctx->spec |= EXT4_SPEC_JQUOTA;
2072         return 0;
2073 }
2074
2075 /*
2076  * Clear the name of the specified quota file.
2077  */
2078 static int unnote_qf_name(struct fs_context *fc, int qtype)
2079 {
2080         struct ext4_fs_context *ctx = fc->fs_private;
2081
2082         if (ctx->s_qf_names[qtype])
2083                 kfree(ctx->s_qf_names[qtype]);
2084
2085         ctx->s_qf_names[qtype] = NULL;
2086         ctx->qname_spec |= 1 << qtype;
2087         ctx->spec |= EXT4_SPEC_JQUOTA;
2088         return 0;
2089 }
2090 #endif
2091
2092 static int ext4_parse_test_dummy_encryption(const struct fs_parameter *param,
2093                                             struct ext4_fs_context *ctx)
2094 {
2095         int err;
2096
2097         if (!IS_ENABLED(CONFIG_FS_ENCRYPTION)) {
2098                 ext4_msg(NULL, KERN_WARNING,
2099                          "test_dummy_encryption option not supported");
2100                 return -EINVAL;
2101         }
2102         err = fscrypt_parse_test_dummy_encryption(param,
2103                                                   &ctx->dummy_enc_policy);
2104         if (err == -EINVAL) {
2105                 ext4_msg(NULL, KERN_WARNING,
2106                          "Value of option \"%s\" is unrecognized", param->key);
2107         } else if (err == -EEXIST) {
2108                 ext4_msg(NULL, KERN_WARNING,
2109                          "Conflicting test_dummy_encryption options");
2110                 return -EINVAL;
2111         }
2112         return err;
2113 }
2114
2115 #define EXT4_SET_CTX(name)                                              \
2116 static inline void ctx_set_##name(struct ext4_fs_context *ctx,          \
2117                                   unsigned long flag)                   \
2118 {                                                                       \
2119         ctx->mask_s_##name |= flag;                                     \
2120         ctx->vals_s_##name |= flag;                                     \
2121 }
2122
2123 #define EXT4_CLEAR_CTX(name)                                            \
2124 static inline void ctx_clear_##name(struct ext4_fs_context *ctx,        \
2125                                     unsigned long flag)                 \
2126 {                                                                       \
2127         ctx->mask_s_##name |= flag;                                     \
2128         ctx->vals_s_##name &= ~flag;                                    \
2129 }
2130
2131 #define EXT4_TEST_CTX(name)                                             \
2132 static inline unsigned long                                             \
2133 ctx_test_##name(struct ext4_fs_context *ctx, unsigned long flag)        \
2134 {                                                                       \
2135         return (ctx->vals_s_##name & flag);                             \
2136 }
2137
2138 EXT4_SET_CTX(flags); /* set only */
2139 EXT4_SET_CTX(mount_opt);
2140 EXT4_CLEAR_CTX(mount_opt);
2141 EXT4_TEST_CTX(mount_opt);
2142 EXT4_SET_CTX(mount_opt2);
2143 EXT4_CLEAR_CTX(mount_opt2);
2144 EXT4_TEST_CTX(mount_opt2);
2145
2146 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
2147 {
2148         struct ext4_fs_context *ctx = fc->fs_private;
2149         struct fs_parse_result result;
2150         const struct mount_opts *m;
2151         int is_remount;
2152         kuid_t uid;
2153         kgid_t gid;
2154         int token;
2155
2156         token = fs_parse(fc, ext4_param_specs, param, &result);
2157         if (token < 0)
2158                 return token;
2159         is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2160
2161         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2162                 if (token == m->token)
2163                         break;
2164
2165         ctx->opt_flags |= m->flags;
2166
2167         if (m->flags & MOPT_EXPLICIT) {
2168                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2169                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_EXPLICIT_DELALLOC);
2170                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2171                         ctx_set_mount_opt2(ctx,
2172                                        EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM);
2173                 } else
2174                         return -EINVAL;
2175         }
2176
2177         if (m->flags & MOPT_NOSUPPORT) {
2178                 ext4_msg(NULL, KERN_ERR, "%s option not supported",
2179                          param->key);
2180                 return 0;
2181         }
2182
2183         switch (token) {
2184 #ifdef CONFIG_QUOTA
2185         case Opt_usrjquota:
2186                 if (!*param->string)
2187                         return unnote_qf_name(fc, USRQUOTA);
2188                 else
2189                         return note_qf_name(fc, USRQUOTA, param);
2190         case Opt_grpjquota:
2191                 if (!*param->string)
2192                         return unnote_qf_name(fc, GRPQUOTA);
2193                 else
2194                         return note_qf_name(fc, GRPQUOTA, param);
2195 #endif
2196         case Opt_sb:
2197                 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2198                         ext4_msg(NULL, KERN_WARNING,
2199                                  "Ignoring %s option on remount", param->key);
2200                 } else {
2201                         ctx->s_sb_block = result.uint_32;
2202                         ctx->spec |= EXT4_SPEC_s_sb_block;
2203                 }
2204                 return 0;
2205         case Opt_removed:
2206                 ext4_msg(NULL, KERN_WARNING, "Ignoring removed %s option",
2207                          param->key);
2208                 return 0;
2209         case Opt_inlinecrypt:
2210 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2211                 ctx_set_flags(ctx, SB_INLINECRYPT);
2212 #else
2213                 ext4_msg(NULL, KERN_ERR, "inline encryption not supported");
2214 #endif
2215                 return 0;
2216         case Opt_errors:
2217                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_ERRORS_MASK);
2218                 ctx_set_mount_opt(ctx, result.uint_32);
2219                 return 0;
2220 #ifdef CONFIG_QUOTA
2221         case Opt_jqfmt:
2222                 ctx->s_jquota_fmt = result.uint_32;
2223                 ctx->spec |= EXT4_SPEC_JQFMT;
2224                 return 0;
2225 #endif
2226         case Opt_data:
2227                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2228                 ctx_set_mount_opt(ctx, result.uint_32);
2229                 ctx->spec |= EXT4_SPEC_DATAJ;
2230                 return 0;
2231         case Opt_commit:
2232                 if (result.uint_32 == 0)
2233                         result.uint_32 = JBD2_DEFAULT_MAX_COMMIT_AGE;
2234                 else if (result.uint_32 > INT_MAX / HZ) {
2235                         ext4_msg(NULL, KERN_ERR,
2236                                  "Invalid commit interval %d, "
2237                                  "must be smaller than %d",
2238                                  result.uint_32, INT_MAX / HZ);
2239                         return -EINVAL;
2240                 }
2241                 ctx->s_commit_interval = HZ * result.uint_32;
2242                 ctx->spec |= EXT4_SPEC_s_commit_interval;
2243                 return 0;
2244         case Opt_debug_want_extra_isize:
2245                 if ((result.uint_32 & 1) || (result.uint_32 < 4)) {
2246                         ext4_msg(NULL, KERN_ERR,
2247                                  "Invalid want_extra_isize %d", result.uint_32);
2248                         return -EINVAL;
2249                 }
2250                 ctx->s_want_extra_isize = result.uint_32;
2251                 ctx->spec |= EXT4_SPEC_s_want_extra_isize;
2252                 return 0;
2253         case Opt_max_batch_time:
2254                 ctx->s_max_batch_time = result.uint_32;
2255                 ctx->spec |= EXT4_SPEC_s_max_batch_time;
2256                 return 0;
2257         case Opt_min_batch_time:
2258                 ctx->s_min_batch_time = result.uint_32;
2259                 ctx->spec |= EXT4_SPEC_s_min_batch_time;
2260                 return 0;
2261         case Opt_inode_readahead_blks:
2262                 if (result.uint_32 &&
2263                     (result.uint_32 > (1 << 30) ||
2264                      !is_power_of_2(result.uint_32))) {
2265                         ext4_msg(NULL, KERN_ERR,
2266                                  "EXT4-fs: inode_readahead_blks must be "
2267                                  "0 or a power of 2 smaller than 2^31");
2268                         return -EINVAL;
2269                 }
2270                 ctx->s_inode_readahead_blks = result.uint_32;
2271                 ctx->spec |= EXT4_SPEC_s_inode_readahead_blks;
2272                 return 0;
2273         case Opt_init_itable:
2274                 ctx_set_mount_opt(ctx, EXT4_MOUNT_INIT_INODE_TABLE);
2275                 ctx->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
2276                 if (param->type == fs_value_is_string)
2277                         ctx->s_li_wait_mult = result.uint_32;
2278                 ctx->spec |= EXT4_SPEC_s_li_wait_mult;
2279                 return 0;
2280         case Opt_max_dir_size_kb:
2281                 ctx->s_max_dir_size_kb = result.uint_32;
2282                 ctx->spec |= EXT4_SPEC_s_max_dir_size_kb;
2283                 return 0;
2284 #ifdef CONFIG_EXT4_DEBUG
2285         case Opt_fc_debug_max_replay:
2286                 ctx->s_fc_debug_max_replay = result.uint_32;
2287                 ctx->spec |= EXT4_SPEC_s_fc_debug_max_replay;
2288                 return 0;
2289 #endif
2290         case Opt_stripe:
2291                 ctx->s_stripe = result.uint_32;
2292                 ctx->spec |= EXT4_SPEC_s_stripe;
2293                 return 0;
2294         case Opt_resuid:
2295                 uid = make_kuid(current_user_ns(), result.uint_32);
2296                 if (!uid_valid(uid)) {
2297                         ext4_msg(NULL, KERN_ERR, "Invalid uid value %d",
2298                                  result.uint_32);
2299                         return -EINVAL;
2300                 }
2301                 ctx->s_resuid = uid;
2302                 ctx->spec |= EXT4_SPEC_s_resuid;
2303                 return 0;
2304         case Opt_resgid:
2305                 gid = make_kgid(current_user_ns(), result.uint_32);
2306                 if (!gid_valid(gid)) {
2307                         ext4_msg(NULL, KERN_ERR, "Invalid gid value %d",
2308                                  result.uint_32);
2309                         return -EINVAL;
2310                 }
2311                 ctx->s_resgid = gid;
2312                 ctx->spec |= EXT4_SPEC_s_resgid;
2313                 return 0;
2314         case Opt_journal_dev:
2315                 if (is_remount) {
2316                         ext4_msg(NULL, KERN_ERR,
2317                                  "Cannot specify journal on remount");
2318                         return -EINVAL;
2319                 }
2320                 ctx->journal_devnum = result.uint_32;
2321                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2322                 return 0;
2323         case Opt_journal_path:
2324         {
2325                 struct inode *journal_inode;
2326                 struct path path;
2327                 int error;
2328
2329                 if (is_remount) {
2330                         ext4_msg(NULL, KERN_ERR,
2331                                  "Cannot specify journal on remount");
2332                         return -EINVAL;
2333                 }
2334
2335                 error = fs_lookup_param(fc, param, 1, LOOKUP_FOLLOW, &path);
2336                 if (error) {
2337                         ext4_msg(NULL, KERN_ERR, "error: could not find "
2338                                  "journal device path");
2339                         return -EINVAL;
2340                 }
2341
2342                 journal_inode = d_inode(path.dentry);
2343                 ctx->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2344                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2345                 path_put(&path);
2346                 return 0;
2347         }
2348         case Opt_journal_ioprio:
2349                 if (result.uint_32 > 7) {
2350                         ext4_msg(NULL, KERN_ERR, "Invalid journal IO priority"
2351                                  " (must be 0-7)");
2352                         return -EINVAL;
2353                 }
2354                 ctx->journal_ioprio =
2355                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, result.uint_32);
2356                 ctx->spec |= EXT4_SPEC_JOURNAL_IOPRIO;
2357                 return 0;
2358         case Opt_test_dummy_encryption:
2359                 return ext4_parse_test_dummy_encryption(param, ctx);
2360         case Opt_dax:
2361         case Opt_dax_type:
2362 #ifdef CONFIG_FS_DAX
2363         {
2364                 int type = (token == Opt_dax) ?
2365                            Opt_dax : result.uint_32;
2366
2367                 switch (type) {
2368                 case Opt_dax:
2369                 case Opt_dax_always:
2370                         ctx_set_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2371                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2372                         break;
2373                 case Opt_dax_never:
2374                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2375                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2376                         break;
2377                 case Opt_dax_inode:
2378                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2379                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2380                         /* Strictly for printing options */
2381                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE);
2382                         break;
2383                 }
2384                 return 0;
2385         }
2386 #else
2387                 ext4_msg(NULL, KERN_INFO, "dax option not supported");
2388                 return -EINVAL;
2389 #endif
2390         case Opt_data_err:
2391                 if (result.uint_32 == Opt_data_err_abort)
2392                         ctx_set_mount_opt(ctx, m->mount_opt);
2393                 else if (result.uint_32 == Opt_data_err_ignore)
2394                         ctx_clear_mount_opt(ctx, m->mount_opt);
2395                 return 0;
2396         case Opt_mb_optimize_scan:
2397                 if (result.int_32 == 1) {
2398                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2399                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2400                 } else if (result.int_32 == 0) {
2401                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2402                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2403                 } else {
2404                         ext4_msg(NULL, KERN_WARNING,
2405                                  "mb_optimize_scan should be set to 0 or 1.");
2406                         return -EINVAL;
2407                 }
2408                 return 0;
2409         }
2410
2411         /*
2412          * At this point we should only be getting options requiring MOPT_SET,
2413          * or MOPT_CLEAR. Anything else is a bug
2414          */
2415         if (m->token == Opt_err) {
2416                 ext4_msg(NULL, KERN_WARNING, "buggy handling of option %s",
2417                          param->key);
2418                 WARN_ON(1);
2419                 return -EINVAL;
2420         }
2421
2422         else {
2423                 unsigned int set = 0;
2424
2425                 if ((param->type == fs_value_is_flag) ||
2426                     result.uint_32 > 0)
2427                         set = 1;
2428
2429                 if (m->flags & MOPT_CLEAR)
2430                         set = !set;
2431                 else if (unlikely(!(m->flags & MOPT_SET))) {
2432                         ext4_msg(NULL, KERN_WARNING,
2433                                  "buggy handling of option %s",
2434                                  param->key);
2435                         WARN_ON(1);
2436                         return -EINVAL;
2437                 }
2438                 if (m->flags & MOPT_2) {
2439                         if (set != 0)
2440                                 ctx_set_mount_opt2(ctx, m->mount_opt);
2441                         else
2442                                 ctx_clear_mount_opt2(ctx, m->mount_opt);
2443                 } else {
2444                         if (set != 0)
2445                                 ctx_set_mount_opt(ctx, m->mount_opt);
2446                         else
2447                                 ctx_clear_mount_opt(ctx, m->mount_opt);
2448                 }
2449         }
2450
2451         return 0;
2452 }
2453
2454 static int parse_options(struct fs_context *fc, char *options)
2455 {
2456         struct fs_parameter param;
2457         int ret;
2458         char *key;
2459
2460         if (!options)
2461                 return 0;
2462
2463         while ((key = strsep(&options, ",")) != NULL) {
2464                 if (*key) {
2465                         size_t v_len = 0;
2466                         char *value = strchr(key, '=');
2467
2468                         param.type = fs_value_is_flag;
2469                         param.string = NULL;
2470
2471                         if (value) {
2472                                 if (value == key)
2473                                         continue;
2474
2475                                 *value++ = 0;
2476                                 v_len = strlen(value);
2477                                 param.string = kmemdup_nul(value, v_len,
2478                                                            GFP_KERNEL);
2479                                 if (!param.string)
2480                                         return -ENOMEM;
2481                                 param.type = fs_value_is_string;
2482                         }
2483
2484                         param.key = key;
2485                         param.size = v_len;
2486
2487                         ret = ext4_parse_param(fc, &param);
2488                         if (param.string)
2489                                 kfree(param.string);
2490                         if (ret < 0)
2491                                 return ret;
2492                 }
2493         }
2494
2495         ret = ext4_validate_options(fc);
2496         if (ret < 0)
2497                 return ret;
2498
2499         return 0;
2500 }
2501
2502 static int parse_apply_sb_mount_options(struct super_block *sb,
2503                                         struct ext4_fs_context *m_ctx)
2504 {
2505         struct ext4_sb_info *sbi = EXT4_SB(sb);
2506         char *s_mount_opts = NULL;
2507         struct ext4_fs_context *s_ctx = NULL;
2508         struct fs_context *fc = NULL;
2509         int ret = -ENOMEM;
2510
2511         if (!sbi->s_es->s_mount_opts[0])
2512                 return 0;
2513
2514         s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
2515                                 sizeof(sbi->s_es->s_mount_opts),
2516                                 GFP_KERNEL);
2517         if (!s_mount_opts)
2518                 return ret;
2519
2520         fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
2521         if (!fc)
2522                 goto out_free;
2523
2524         s_ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2525         if (!s_ctx)
2526                 goto out_free;
2527
2528         fc->fs_private = s_ctx;
2529         fc->s_fs_info = sbi;
2530
2531         ret = parse_options(fc, s_mount_opts);
2532         if (ret < 0)
2533                 goto parse_failed;
2534
2535         ret = ext4_check_opt_consistency(fc, sb);
2536         if (ret < 0) {
2537 parse_failed:
2538                 ext4_msg(sb, KERN_WARNING,
2539                          "failed to parse options in superblock: %s",
2540                          s_mount_opts);
2541                 ret = 0;
2542                 goto out_free;
2543         }
2544
2545         if (s_ctx->spec & EXT4_SPEC_JOURNAL_DEV)
2546                 m_ctx->journal_devnum = s_ctx->journal_devnum;
2547         if (s_ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)
2548                 m_ctx->journal_ioprio = s_ctx->journal_ioprio;
2549
2550         ext4_apply_options(fc, sb);
2551         ret = 0;
2552
2553 out_free:
2554         if (fc) {
2555                 ext4_fc_free(fc);
2556                 kfree(fc);
2557         }
2558         kfree(s_mount_opts);
2559         return ret;
2560 }
2561
2562 static void ext4_apply_quota_options(struct fs_context *fc,
2563                                      struct super_block *sb)
2564 {
2565 #ifdef CONFIG_QUOTA
2566         bool quota_feature = ext4_has_feature_quota(sb);
2567         struct ext4_fs_context *ctx = fc->fs_private;
2568         struct ext4_sb_info *sbi = EXT4_SB(sb);
2569         char *qname;
2570         int i;
2571
2572         if (quota_feature)
2573                 return;
2574
2575         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2576                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2577                         if (!(ctx->qname_spec & (1 << i)))
2578                                 continue;
2579
2580                         qname = ctx->s_qf_names[i]; /* May be NULL */
2581                         if (qname)
2582                                 set_opt(sb, QUOTA);
2583                         ctx->s_qf_names[i] = NULL;
2584                         qname = rcu_replace_pointer(sbi->s_qf_names[i], qname,
2585                                                 lockdep_is_held(&sb->s_umount));
2586                         if (qname)
2587                                 kfree_rcu_mightsleep(qname);
2588                 }
2589         }
2590
2591         if (ctx->spec & EXT4_SPEC_JQFMT)
2592                 sbi->s_jquota_fmt = ctx->s_jquota_fmt;
2593 #endif
2594 }
2595
2596 /*
2597  * Check quota settings consistency.
2598  */
2599 static int ext4_check_quota_consistency(struct fs_context *fc,
2600                                         struct super_block *sb)
2601 {
2602 #ifdef CONFIG_QUOTA
2603         struct ext4_fs_context *ctx = fc->fs_private;
2604         struct ext4_sb_info *sbi = EXT4_SB(sb);
2605         bool quota_feature = ext4_has_feature_quota(sb);
2606         bool quota_loaded = sb_any_quota_loaded(sb);
2607         bool usr_qf_name, grp_qf_name, usrquota, grpquota;
2608         int quota_flags, i;
2609
2610         /*
2611          * We do the test below only for project quotas. 'usrquota' and
2612          * 'grpquota' mount options are allowed even without quota feature
2613          * to support legacy quotas in quota files.
2614          */
2615         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_PRJQUOTA) &&
2616             !ext4_has_feature_project(sb)) {
2617                 ext4_msg(NULL, KERN_ERR, "Project quota feature not enabled. "
2618                          "Cannot enable project quota enforcement.");
2619                 return -EINVAL;
2620         }
2621
2622         quota_flags = EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2623                       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA;
2624         if (quota_loaded &&
2625             ctx->mask_s_mount_opt & quota_flags &&
2626             !ctx_test_mount_opt(ctx, quota_flags))
2627                 goto err_quota_change;
2628
2629         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2630
2631                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2632                         if (!(ctx->qname_spec & (1 << i)))
2633                                 continue;
2634
2635                         if (quota_loaded &&
2636                             !!sbi->s_qf_names[i] != !!ctx->s_qf_names[i])
2637                                 goto err_jquota_change;
2638
2639                         if (sbi->s_qf_names[i] && ctx->s_qf_names[i] &&
2640                             strcmp(get_qf_name(sb, sbi, i),
2641                                    ctx->s_qf_names[i]) != 0)
2642                                 goto err_jquota_specified;
2643                 }
2644
2645                 if (quota_feature) {
2646                         ext4_msg(NULL, KERN_INFO,
2647                                  "Journaled quota options ignored when "
2648                                  "QUOTA feature is enabled");
2649                         return 0;
2650                 }
2651         }
2652
2653         if (ctx->spec & EXT4_SPEC_JQFMT) {
2654                 if (sbi->s_jquota_fmt != ctx->s_jquota_fmt && quota_loaded)
2655                         goto err_jquota_change;
2656                 if (quota_feature) {
2657                         ext4_msg(NULL, KERN_INFO, "Quota format mount options "
2658                                  "ignored when QUOTA feature is enabled");
2659                         return 0;
2660                 }
2661         }
2662
2663         /* Make sure we don't mix old and new quota format */
2664         usr_qf_name = (get_qf_name(sb, sbi, USRQUOTA) ||
2665                        ctx->s_qf_names[USRQUOTA]);
2666         grp_qf_name = (get_qf_name(sb, sbi, GRPQUOTA) ||
2667                        ctx->s_qf_names[GRPQUOTA]);
2668
2669         usrquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2670                     test_opt(sb, USRQUOTA));
2671
2672         grpquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) ||
2673                     test_opt(sb, GRPQUOTA));
2674
2675         if (usr_qf_name) {
2676                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2677                 usrquota = false;
2678         }
2679         if (grp_qf_name) {
2680                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2681                 grpquota = false;
2682         }
2683
2684         if (usr_qf_name || grp_qf_name) {
2685                 if (usrquota || grpquota) {
2686                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2687                                  "format mixing");
2688                         return -EINVAL;
2689                 }
2690
2691                 if (!(ctx->spec & EXT4_SPEC_JQFMT || sbi->s_jquota_fmt)) {
2692                         ext4_msg(NULL, KERN_ERR, "journaled quota format "
2693                                  "not specified");
2694                         return -EINVAL;
2695                 }
2696         }
2697
2698         return 0;
2699
2700 err_quota_change:
2701         ext4_msg(NULL, KERN_ERR,
2702                  "Cannot change quota options when quota turned on");
2703         return -EINVAL;
2704 err_jquota_change:
2705         ext4_msg(NULL, KERN_ERR, "Cannot change journaled quota "
2706                  "options when quota turned on");
2707         return -EINVAL;
2708 err_jquota_specified:
2709         ext4_msg(NULL, KERN_ERR, "%s quota file already specified",
2710                  QTYPE2NAME(i));
2711         return -EINVAL;
2712 #else
2713         return 0;
2714 #endif
2715 }
2716
2717 static int ext4_check_test_dummy_encryption(const struct fs_context *fc,
2718                                             struct super_block *sb)
2719 {
2720         const struct ext4_fs_context *ctx = fc->fs_private;
2721         const struct ext4_sb_info *sbi = EXT4_SB(sb);
2722
2723         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy))
2724                 return 0;
2725
2726         if (!ext4_has_feature_encrypt(sb)) {
2727                 ext4_msg(NULL, KERN_WARNING,
2728                          "test_dummy_encryption requires encrypt feature");
2729                 return -EINVAL;
2730         }
2731         /*
2732          * This mount option is just for testing, and it's not worthwhile to
2733          * implement the extra complexity (e.g. RCU protection) that would be
2734          * needed to allow it to be set or changed during remount.  We do allow
2735          * it to be specified during remount, but only if there is no change.
2736          */
2737         if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2738                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2739                                                  &ctx->dummy_enc_policy))
2740                         return 0;
2741                 ext4_msg(NULL, KERN_WARNING,
2742                          "Can't set or change test_dummy_encryption on remount");
2743                 return -EINVAL;
2744         }
2745         /* Also make sure s_mount_opts didn't contain a conflicting value. */
2746         if (fscrypt_is_dummy_policy_set(&sbi->s_dummy_enc_policy)) {
2747                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2748                                                  &ctx->dummy_enc_policy))
2749                         return 0;
2750                 ext4_msg(NULL, KERN_WARNING,
2751                          "Conflicting test_dummy_encryption options");
2752                 return -EINVAL;
2753         }
2754         return 0;
2755 }
2756
2757 static void ext4_apply_test_dummy_encryption(struct ext4_fs_context *ctx,
2758                                              struct super_block *sb)
2759 {
2760         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy) ||
2761             /* if already set, it was already verified to be the same */
2762             fscrypt_is_dummy_policy_set(&EXT4_SB(sb)->s_dummy_enc_policy))
2763                 return;
2764         EXT4_SB(sb)->s_dummy_enc_policy = ctx->dummy_enc_policy;
2765         memset(&ctx->dummy_enc_policy, 0, sizeof(ctx->dummy_enc_policy));
2766         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2767 }
2768
2769 static int ext4_check_opt_consistency(struct fs_context *fc,
2770                                       struct super_block *sb)
2771 {
2772         struct ext4_fs_context *ctx = fc->fs_private;
2773         struct ext4_sb_info *sbi = fc->s_fs_info;
2774         int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2775         int err;
2776
2777         if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2778                 ext4_msg(NULL, KERN_ERR,
2779                          "Mount option(s) incompatible with ext2");
2780                 return -EINVAL;
2781         }
2782         if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2783                 ext4_msg(NULL, KERN_ERR,
2784                          "Mount option(s) incompatible with ext3");
2785                 return -EINVAL;
2786         }
2787
2788         if (ctx->s_want_extra_isize >
2789             (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2790                 ext4_msg(NULL, KERN_ERR,
2791                          "Invalid want_extra_isize %d",
2792                          ctx->s_want_extra_isize);
2793                 return -EINVAL;
2794         }
2795
2796         err = ext4_check_test_dummy_encryption(fc, sb);
2797         if (err)
2798                 return err;
2799
2800         if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2801                 if (!sbi->s_journal) {
2802                         ext4_msg(NULL, KERN_WARNING,
2803                                  "Remounting file system with no journal "
2804                                  "so ignoring journalled data option");
2805                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2806                 } else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2807                            test_opt(sb, DATA_FLAGS)) {
2808                         ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2809                                  "on remount");
2810                         return -EINVAL;
2811                 }
2812         }
2813
2814         if (is_remount) {
2815                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2816                     (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2817                         ext4_msg(NULL, KERN_ERR, "can't mount with "
2818                                  "both data=journal and dax");
2819                         return -EINVAL;
2820                 }
2821
2822                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2823                     (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2824                      (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2825 fail_dax_change_remount:
2826                         ext4_msg(NULL, KERN_ERR, "can't change "
2827                                  "dax mount option while remounting");
2828                         return -EINVAL;
2829                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2830                          (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2831                           (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2832                         goto fail_dax_change_remount;
2833                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2834                            ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2835                             (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2836                             !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2837                         goto fail_dax_change_remount;
2838                 }
2839         }
2840
2841         return ext4_check_quota_consistency(fc, sb);
2842 }
2843
2844 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2845 {
2846         struct ext4_fs_context *ctx = fc->fs_private;
2847         struct ext4_sb_info *sbi = fc->s_fs_info;
2848
2849         sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2850         sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2851         sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2852         sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2853         sb->s_flags &= ~ctx->mask_s_flags;
2854         sb->s_flags |= ctx->vals_s_flags;
2855
2856 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2857         APPLY(s_commit_interval);
2858         APPLY(s_stripe);
2859         APPLY(s_max_batch_time);
2860         APPLY(s_min_batch_time);
2861         APPLY(s_want_extra_isize);
2862         APPLY(s_inode_readahead_blks);
2863         APPLY(s_max_dir_size_kb);
2864         APPLY(s_li_wait_mult);
2865         APPLY(s_resgid);
2866         APPLY(s_resuid);
2867
2868 #ifdef CONFIG_EXT4_DEBUG
2869         APPLY(s_fc_debug_max_replay);
2870 #endif
2871
2872         ext4_apply_quota_options(fc, sb);
2873         ext4_apply_test_dummy_encryption(ctx, sb);
2874 }
2875
2876
2877 static int ext4_validate_options(struct fs_context *fc)
2878 {
2879 #ifdef CONFIG_QUOTA
2880         struct ext4_fs_context *ctx = fc->fs_private;
2881         char *usr_qf_name, *grp_qf_name;
2882
2883         usr_qf_name = ctx->s_qf_names[USRQUOTA];
2884         grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2885
2886         if (usr_qf_name || grp_qf_name) {
2887                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2888                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2889
2890                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2891                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2892
2893                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2894                     ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2895                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2896                                  "format mixing");
2897                         return -EINVAL;
2898                 }
2899         }
2900 #endif
2901         return 1;
2902 }
2903
2904 static inline void ext4_show_quota_options(struct seq_file *seq,
2905                                            struct super_block *sb)
2906 {
2907 #if defined(CONFIG_QUOTA)
2908         struct ext4_sb_info *sbi = EXT4_SB(sb);
2909         char *usr_qf_name, *grp_qf_name;
2910
2911         if (sbi->s_jquota_fmt) {
2912                 char *fmtname = "";
2913
2914                 switch (sbi->s_jquota_fmt) {
2915                 case QFMT_VFS_OLD:
2916                         fmtname = "vfsold";
2917                         break;
2918                 case QFMT_VFS_V0:
2919                         fmtname = "vfsv0";
2920                         break;
2921                 case QFMT_VFS_V1:
2922                         fmtname = "vfsv1";
2923                         break;
2924                 }
2925                 seq_printf(seq, ",jqfmt=%s", fmtname);
2926         }
2927
2928         rcu_read_lock();
2929         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2930         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2931         if (usr_qf_name)
2932                 seq_show_option(seq, "usrjquota", usr_qf_name);
2933         if (grp_qf_name)
2934                 seq_show_option(seq, "grpjquota", grp_qf_name);
2935         rcu_read_unlock();
2936 #endif
2937 }
2938
2939 static const char *token2str(int token)
2940 {
2941         const struct fs_parameter_spec *spec;
2942
2943         for (spec = ext4_param_specs; spec->name != NULL; spec++)
2944                 if (spec->opt == token && !spec->type)
2945                         break;
2946         return spec->name;
2947 }
2948
2949 /*
2950  * Show an option if
2951  *  - it's set to a non-default value OR
2952  *  - if the per-sb default is different from the global default
2953  */
2954 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2955                               int nodefs)
2956 {
2957         struct ext4_sb_info *sbi = EXT4_SB(sb);
2958         struct ext4_super_block *es = sbi->s_es;
2959         int def_errors;
2960         const struct mount_opts *m;
2961         char sep = nodefs ? '\n' : ',';
2962
2963 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2964 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2965
2966         if (sbi->s_sb_block != 1)
2967                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2968
2969         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2970                 int want_set = m->flags & MOPT_SET;
2971                 int opt_2 = m->flags & MOPT_2;
2972                 unsigned int mount_opt, def_mount_opt;
2973
2974                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2975                     m->flags & MOPT_SKIP)
2976                         continue;
2977
2978                 if (opt_2) {
2979                         mount_opt = sbi->s_mount_opt2;
2980                         def_mount_opt = sbi->s_def_mount_opt2;
2981                 } else {
2982                         mount_opt = sbi->s_mount_opt;
2983                         def_mount_opt = sbi->s_def_mount_opt;
2984                 }
2985                 /* skip if same as the default */
2986                 if (!nodefs && !(m->mount_opt & (mount_opt ^ def_mount_opt)))
2987                         continue;
2988                 /* select Opt_noFoo vs Opt_Foo */
2989                 if ((want_set &&
2990                      (mount_opt & m->mount_opt) != m->mount_opt) ||
2991                     (!want_set && (mount_opt & m->mount_opt)))
2992                         continue;
2993                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2994         }
2995
2996         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2997             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2998                 SEQ_OPTS_PRINT("resuid=%u",
2999                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
3000         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
3001             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
3002                 SEQ_OPTS_PRINT("resgid=%u",
3003                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
3004         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
3005         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
3006                 SEQ_OPTS_PUTS("errors=remount-ro");
3007         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
3008                 SEQ_OPTS_PUTS("errors=continue");
3009         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
3010                 SEQ_OPTS_PUTS("errors=panic");
3011         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
3012                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
3013         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
3014                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
3015         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
3016                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
3017         if (nodefs || sbi->s_stripe)
3018                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
3019         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
3020                         (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
3021                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3022                         SEQ_OPTS_PUTS("data=journal");
3023                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3024                         SEQ_OPTS_PUTS("data=ordered");
3025                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
3026                         SEQ_OPTS_PUTS("data=writeback");
3027         }
3028         if (nodefs ||
3029             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
3030                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
3031                                sbi->s_inode_readahead_blks);
3032
3033         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
3034                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
3035                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
3036         if (nodefs || sbi->s_max_dir_size_kb)
3037                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
3038         if (test_opt(sb, DATA_ERR_ABORT))
3039                 SEQ_OPTS_PUTS("data_err=abort");
3040
3041         fscrypt_show_test_dummy_encryption(seq, sep, sb);
3042
3043         if (sb->s_flags & SB_INLINECRYPT)
3044                 SEQ_OPTS_PUTS("inlinecrypt");
3045
3046         if (test_opt(sb, DAX_ALWAYS)) {
3047                 if (IS_EXT2_SB(sb))
3048                         SEQ_OPTS_PUTS("dax");
3049                 else
3050                         SEQ_OPTS_PUTS("dax=always");
3051         } else if (test_opt2(sb, DAX_NEVER)) {
3052                 SEQ_OPTS_PUTS("dax=never");
3053         } else if (test_opt2(sb, DAX_INODE)) {
3054                 SEQ_OPTS_PUTS("dax=inode");
3055         }
3056
3057         if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3058                         !test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3059                 SEQ_OPTS_PUTS("mb_optimize_scan=0");
3060         } else if (sbi->s_groups_count < MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3061                         test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3062                 SEQ_OPTS_PUTS("mb_optimize_scan=1");
3063         }
3064
3065         ext4_show_quota_options(seq, sb);
3066         return 0;
3067 }
3068
3069 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
3070 {
3071         return _ext4_show_options(seq, root->d_sb, 0);
3072 }
3073
3074 int ext4_seq_options_show(struct seq_file *seq, void *offset)
3075 {
3076         struct super_block *sb = seq->private;
3077         int rc;
3078
3079         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
3080         rc = _ext4_show_options(seq, sb, 1);
3081         seq_puts(seq, "\n");
3082         return rc;
3083 }
3084
3085 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3086                             int read_only)
3087 {
3088         struct ext4_sb_info *sbi = EXT4_SB(sb);
3089         int err = 0;
3090
3091         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3092                 ext4_msg(sb, KERN_ERR, "revision level too high, "
3093                          "forcing read-only mode");
3094                 err = -EROFS;
3095                 goto done;
3096         }
3097         if (read_only)
3098                 goto done;
3099         if (!(sbi->s_mount_state & EXT4_VALID_FS))
3100                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3101                          "running e2fsck is recommended");
3102         else if (sbi->s_mount_state & EXT4_ERROR_FS)
3103                 ext4_msg(sb, KERN_WARNING,
3104                          "warning: mounting fs with errors, "
3105                          "running e2fsck is recommended");
3106         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3107                  le16_to_cpu(es->s_mnt_count) >=
3108                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3109                 ext4_msg(sb, KERN_WARNING,
3110                          "warning: maximal mount count reached, "
3111                          "running e2fsck is recommended");
3112         else if (le32_to_cpu(es->s_checkinterval) &&
3113                  (ext4_get_tstamp(es, s_lastcheck) +
3114                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3115                 ext4_msg(sb, KERN_WARNING,
3116                          "warning: checktime reached, "
3117                          "running e2fsck is recommended");
3118         if (!sbi->s_journal)
3119                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3120         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3121                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3122         le16_add_cpu(&es->s_mnt_count, 1);
3123         ext4_update_tstamp(es, s_mtime);
3124         if (sbi->s_journal) {
3125                 ext4_set_feature_journal_needs_recovery(sb);
3126                 if (ext4_has_feature_orphan_file(sb))
3127                         ext4_set_feature_orphan_present(sb);
3128         }
3129
3130         err = ext4_commit_super(sb);
3131 done:
3132         if (test_opt(sb, DEBUG))
3133                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3134                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3135                         sb->s_blocksize,
3136                         sbi->s_groups_count,
3137                         EXT4_BLOCKS_PER_GROUP(sb),
3138                         EXT4_INODES_PER_GROUP(sb),
3139                         sbi->s_mount_opt, sbi->s_mount_opt2);
3140         return err;
3141 }
3142
3143 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3144 {
3145         struct ext4_sb_info *sbi = EXT4_SB(sb);
3146         struct flex_groups **old_groups, **new_groups;
3147         int size, i, j;
3148
3149         if (!sbi->s_log_groups_per_flex)
3150                 return 0;
3151
3152         size = ext4_flex_group(sbi, ngroup - 1) + 1;
3153         if (size <= sbi->s_flex_groups_allocated)
3154                 return 0;
3155
3156         new_groups = kvzalloc(roundup_pow_of_two(size *
3157                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3158         if (!new_groups) {
3159                 ext4_msg(sb, KERN_ERR,
3160                          "not enough memory for %d flex group pointers", size);
3161                 return -ENOMEM;
3162         }
3163         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3164                 new_groups[i] = kvzalloc(roundup_pow_of_two(
3165                                          sizeof(struct flex_groups)),
3166                                          GFP_KERNEL);
3167                 if (!new_groups[i]) {
3168                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
3169                                 kvfree(new_groups[j]);
3170                         kvfree(new_groups);
3171                         ext4_msg(sb, KERN_ERR,
3172                                  "not enough memory for %d flex groups", size);
3173                         return -ENOMEM;
3174                 }
3175         }
3176         rcu_read_lock();
3177         old_groups = rcu_dereference(sbi->s_flex_groups);
3178         if (old_groups)
3179                 memcpy(new_groups, old_groups,
3180                        (sbi->s_flex_groups_allocated *
3181                         sizeof(struct flex_groups *)));
3182         rcu_read_unlock();
3183         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3184         sbi->s_flex_groups_allocated = size;
3185         if (old_groups)
3186                 ext4_kvfree_array_rcu(old_groups);
3187         return 0;
3188 }
3189
3190 static int ext4_fill_flex_info(struct super_block *sb)
3191 {
3192         struct ext4_sb_info *sbi = EXT4_SB(sb);
3193         struct ext4_group_desc *gdp = NULL;
3194         struct flex_groups *fg;
3195         ext4_group_t flex_group;
3196         int i, err;
3197
3198         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3199         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3200                 sbi->s_log_groups_per_flex = 0;
3201                 return 1;
3202         }
3203
3204         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3205         if (err)
3206                 goto failed;
3207
3208         for (i = 0; i < sbi->s_groups_count; i++) {
3209                 gdp = ext4_get_group_desc(sb, i, NULL);
3210
3211                 flex_group = ext4_flex_group(sbi, i);
3212                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3213                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3214                 atomic64_add(ext4_free_group_clusters(sb, gdp),
3215                              &fg->free_clusters);
3216                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3217         }
3218
3219         return 1;
3220 failed:
3221         return 0;
3222 }
3223
3224 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3225                                    struct ext4_group_desc *gdp)
3226 {
3227         int offset = offsetof(struct ext4_group_desc, bg_checksum);
3228         __u16 crc = 0;
3229         __le32 le_group = cpu_to_le32(block_group);
3230         struct ext4_sb_info *sbi = EXT4_SB(sb);
3231
3232         if (ext4_has_metadata_csum(sbi->s_sb)) {
3233                 /* Use new metadata_csum algorithm */
3234                 __u32 csum32;
3235                 __u16 dummy_csum = 0;
3236
3237                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
3238                                      sizeof(le_group));
3239                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
3240                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
3241                                      sizeof(dummy_csum));
3242                 offset += sizeof(dummy_csum);
3243                 if (offset < sbi->s_desc_size)
3244                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
3245                                              sbi->s_desc_size - offset);
3246
3247                 crc = csum32 & 0xFFFF;
3248                 goto out;
3249         }
3250
3251         /* old crc16 code */
3252         if (!ext4_has_feature_gdt_csum(sb))
3253                 return 0;
3254
3255         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3256         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3257         crc = crc16(crc, (__u8 *)gdp, offset);
3258         offset += sizeof(gdp->bg_checksum); /* skip checksum */
3259         /* for checksum of struct ext4_group_desc do the rest...*/
3260         if (ext4_has_feature_64bit(sb) && offset < sbi->s_desc_size)
3261                 crc = crc16(crc, (__u8 *)gdp + offset,
3262                             sbi->s_desc_size - offset);
3263
3264 out:
3265         return cpu_to_le16(crc);
3266 }
3267
3268 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3269                                 struct ext4_group_desc *gdp)
3270 {
3271         if (ext4_has_group_desc_csum(sb) &&
3272             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3273                 return 0;
3274
3275         return 1;
3276 }
3277
3278 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3279                               struct ext4_group_desc *gdp)
3280 {
3281         if (!ext4_has_group_desc_csum(sb))
3282                 return;
3283         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3284 }
3285
3286 /* Called at mount-time, super-block is locked */
3287 static int ext4_check_descriptors(struct super_block *sb,
3288                                   ext4_fsblk_t sb_block,
3289                                   ext4_group_t *first_not_zeroed)
3290 {
3291         struct ext4_sb_info *sbi = EXT4_SB(sb);
3292         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3293         ext4_fsblk_t last_block;
3294         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3295         ext4_fsblk_t block_bitmap;
3296         ext4_fsblk_t inode_bitmap;
3297         ext4_fsblk_t inode_table;
3298         int flexbg_flag = 0;
3299         ext4_group_t i, grp = sbi->s_groups_count;
3300
3301         if (ext4_has_feature_flex_bg(sb))
3302                 flexbg_flag = 1;
3303
3304         ext4_debug("Checking group descriptors");
3305
3306         for (i = 0; i < sbi->s_groups_count; i++) {
3307                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3308
3309                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
3310                         last_block = ext4_blocks_count(sbi->s_es) - 1;
3311                 else
3312                         last_block = first_block +
3313                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
3314
3315                 if ((grp == sbi->s_groups_count) &&
3316                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3317                         grp = i;
3318
3319                 block_bitmap = ext4_block_bitmap(sb, gdp);
3320                 if (block_bitmap == sb_block) {
3321                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3322                                  "Block bitmap for group %u overlaps "
3323                                  "superblock", i);
3324                         if (!sb_rdonly(sb))
3325                                 return 0;
3326                 }
3327                 if (block_bitmap >= sb_block + 1 &&
3328                     block_bitmap <= last_bg_block) {
3329                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3330                                  "Block bitmap for group %u overlaps "
3331                                  "block group descriptors", i);
3332                         if (!sb_rdonly(sb))
3333                                 return 0;
3334                 }
3335                 if (block_bitmap < first_block || block_bitmap > last_block) {
3336                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3337                                "Block bitmap for group %u not in group "
3338                                "(block %llu)!", i, block_bitmap);
3339                         return 0;
3340                 }
3341                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
3342                 if (inode_bitmap == sb_block) {
3343                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3344                                  "Inode bitmap for group %u overlaps "
3345                                  "superblock", i);
3346                         if (!sb_rdonly(sb))
3347                                 return 0;
3348                 }
3349                 if (inode_bitmap >= sb_block + 1 &&
3350                     inode_bitmap <= last_bg_block) {
3351                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3352                                  "Inode bitmap for group %u overlaps "
3353                                  "block group descriptors", i);
3354                         if (!sb_rdonly(sb))
3355                                 return 0;
3356                 }
3357                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
3358                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3359                                "Inode bitmap for group %u not in group "
3360                                "(block %llu)!", i, inode_bitmap);
3361                         return 0;
3362                 }
3363                 inode_table = ext4_inode_table(sb, gdp);
3364                 if (inode_table == sb_block) {
3365                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3366                                  "Inode table for group %u overlaps "
3367                                  "superblock", i);
3368                         if (!sb_rdonly(sb))
3369                                 return 0;
3370                 }
3371                 if (inode_table >= sb_block + 1 &&
3372                     inode_table <= last_bg_block) {
3373                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3374                                  "Inode table for group %u overlaps "
3375                                  "block group descriptors", i);
3376                         if (!sb_rdonly(sb))
3377                                 return 0;
3378                 }
3379                 if (inode_table < first_block ||
3380                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
3381                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3382                                "Inode table for group %u not in group "
3383                                "(block %llu)!", i, inode_table);
3384                         return 0;
3385                 }
3386                 ext4_lock_group(sb, i);
3387                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3388                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3389                                  "Checksum for group %u failed (%u!=%u)",
3390                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3391                                      gdp)), le16_to_cpu(gdp->bg_checksum));
3392                         if (!sb_rdonly(sb)) {
3393                                 ext4_unlock_group(sb, i);
3394                                 return 0;
3395                         }
3396                 }
3397                 ext4_unlock_group(sb, i);
3398                 if (!flexbg_flag)
3399                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
3400         }
3401         if (NULL != first_not_zeroed)
3402                 *first_not_zeroed = grp;
3403         return 1;
3404 }
3405
3406 /*
3407  * Maximal extent format file size.
3408  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3409  * extent format containers, within a sector_t, and within i_blocks
3410  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3411  * so that won't be a limiting factor.
3412  *
3413  * However there is other limiting factor. We do store extents in the form
3414  * of starting block and length, hence the resulting length of the extent
3415  * covering maximum file size must fit into on-disk format containers as
3416  * well. Given that length is always by 1 unit bigger than max unit (because
3417  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3418  *
3419  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3420  */
3421 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3422 {
3423         loff_t res;
3424         loff_t upper_limit = MAX_LFS_FILESIZE;
3425
3426         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3427
3428         if (!has_huge_files) {
3429                 upper_limit = (1LL << 32) - 1;
3430
3431                 /* total blocks in file system block size */
3432                 upper_limit >>= (blkbits - 9);
3433                 upper_limit <<= blkbits;
3434         }
3435
3436         /*
3437          * 32-bit extent-start container, ee_block. We lower the maxbytes
3438          * by one fs block, so ee_len can cover the extent of maximum file
3439          * size
3440          */
3441         res = (1LL << 32) - 1;
3442         res <<= blkbits;
3443
3444         /* Sanity check against vm- & vfs- imposed limits */
3445         if (res > upper_limit)
3446                 res = upper_limit;
3447
3448         return res;
3449 }
3450
3451 /*
3452  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3453  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3454  * We need to be 1 filesystem block less than the 2^48 sector limit.
3455  */
3456 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3457 {
3458         loff_t upper_limit, res = EXT4_NDIR_BLOCKS;
3459         int meta_blocks;
3460         unsigned int ppb = 1 << (bits - 2);
3461
3462         /*
3463          * This is calculated to be the largest file size for a dense, block
3464          * mapped file such that the file's total number of 512-byte sectors,
3465          * including data and all indirect blocks, does not exceed (2^48 - 1).
3466          *
3467          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3468          * number of 512-byte sectors of the file.
3469          */
3470         if (!has_huge_files) {
3471                 /*
3472                  * !has_huge_files or implies that the inode i_block field
3473                  * represents total file blocks in 2^32 512-byte sectors ==
3474                  * size of vfs inode i_blocks * 8
3475                  */
3476                 upper_limit = (1LL << 32) - 1;
3477
3478                 /* total blocks in file system block size */
3479                 upper_limit >>= (bits - 9);
3480
3481         } else {
3482                 /*
3483                  * We use 48 bit ext4_inode i_blocks
3484                  * With EXT4_HUGE_FILE_FL set the i_blocks
3485                  * represent total number of blocks in
3486                  * file system block size
3487                  */
3488                 upper_limit = (1LL << 48) - 1;
3489
3490         }
3491
3492         /* Compute how many blocks we can address by block tree */
3493         res += ppb;
3494         res += ppb * ppb;
3495         res += ((loff_t)ppb) * ppb * ppb;
3496         /* Compute how many metadata blocks are needed */
3497         meta_blocks = 1;
3498         meta_blocks += 1 + ppb;
3499         meta_blocks += 1 + ppb + ppb * ppb;
3500         /* Does block tree limit file size? */
3501         if (res + meta_blocks <= upper_limit)
3502                 goto check_lfs;
3503
3504         res = upper_limit;
3505         /* How many metadata blocks are needed for addressing upper_limit? */
3506         upper_limit -= EXT4_NDIR_BLOCKS;
3507         /* indirect blocks */
3508         meta_blocks = 1;
3509         upper_limit -= ppb;
3510         /* double indirect blocks */
3511         if (upper_limit < ppb * ppb) {
3512                 meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb);
3513                 res -= meta_blocks;
3514                 goto check_lfs;
3515         }
3516         meta_blocks += 1 + ppb;
3517         upper_limit -= ppb * ppb;
3518         /* tripple indirect blocks for the rest */
3519         meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb) +
3520                 DIV_ROUND_UP_ULL(upper_limit, ppb*ppb);
3521         res -= meta_blocks;
3522 check_lfs:
3523         res <<= bits;
3524         if (res > MAX_LFS_FILESIZE)
3525                 res = MAX_LFS_FILESIZE;
3526
3527         return res;
3528 }
3529
3530 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3531                                    ext4_fsblk_t logical_sb_block, int nr)
3532 {
3533         struct ext4_sb_info *sbi = EXT4_SB(sb);
3534         ext4_group_t bg, first_meta_bg;
3535         int has_super = 0;
3536
3537         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3538
3539         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3540                 return logical_sb_block + nr + 1;
3541         bg = sbi->s_desc_per_block * nr;
3542         if (ext4_bg_has_super(sb, bg))
3543                 has_super = 1;
3544
3545         /*
3546          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3547          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3548          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3549          * compensate.
3550          */
3551         if (sb->s_blocksize == 1024 && nr == 0 &&
3552             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3553                 has_super++;
3554
3555         return (has_super + ext4_group_first_block_no(sb, bg));
3556 }
3557
3558 /**
3559  * ext4_get_stripe_size: Get the stripe size.
3560  * @sbi: In memory super block info
3561  *
3562  * If we have specified it via mount option, then
3563  * use the mount option value. If the value specified at mount time is
3564  * greater than the blocks per group use the super block value.
3565  * If the super block value is greater than blocks per group return 0.
3566  * Allocator needs it be less than blocks per group.
3567  *
3568  */
3569 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3570 {
3571         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3572         unsigned long stripe_width =
3573                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3574         int ret;
3575
3576         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3577                 ret = sbi->s_stripe;
3578         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3579                 ret = stripe_width;
3580         else if (stride && stride <= sbi->s_blocks_per_group)
3581                 ret = stride;
3582         else
3583                 ret = 0;
3584
3585         /*
3586          * If the stripe width is 1, this makes no sense and
3587          * we set it to 0 to turn off stripe handling code.
3588          */
3589         if (ret <= 1)
3590                 ret = 0;
3591
3592         return ret;
3593 }
3594
3595 /*
3596  * Check whether this filesystem can be mounted based on
3597  * the features present and the RDONLY/RDWR mount requested.
3598  * Returns 1 if this filesystem can be mounted as requested,
3599  * 0 if it cannot be.
3600  */
3601 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3602 {
3603         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3604                 ext4_msg(sb, KERN_ERR,
3605                         "Couldn't mount because of "
3606                         "unsupported optional features (%x)",
3607                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3608                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3609                 return 0;
3610         }
3611
3612 #if !IS_ENABLED(CONFIG_UNICODE)
3613         if (ext4_has_feature_casefold(sb)) {
3614                 ext4_msg(sb, KERN_ERR,
3615                          "Filesystem with casefold feature cannot be "
3616                          "mounted without CONFIG_UNICODE");
3617                 return 0;
3618         }
3619 #endif
3620
3621         if (readonly)
3622                 return 1;
3623
3624         if (ext4_has_feature_readonly(sb)) {
3625                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3626                 sb->s_flags |= SB_RDONLY;
3627                 return 1;
3628         }
3629
3630         /* Check that feature set is OK for a read-write mount */
3631         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3632                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3633                          "unsupported optional features (%x)",
3634                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3635                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3636                 return 0;
3637         }
3638         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3639                 ext4_msg(sb, KERN_ERR,
3640                          "Can't support bigalloc feature without "
3641                          "extents feature\n");
3642                 return 0;
3643         }
3644
3645 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3646         if (!readonly && (ext4_has_feature_quota(sb) ||
3647                           ext4_has_feature_project(sb))) {
3648                 ext4_msg(sb, KERN_ERR,
3649                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3650                 return 0;
3651         }
3652 #endif  /* CONFIG_QUOTA */
3653         return 1;
3654 }
3655
3656 /*
3657  * This function is called once a day if we have errors logged
3658  * on the file system
3659  */
3660 static void print_daily_error_info(struct timer_list *t)
3661 {
3662         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3663         struct super_block *sb = sbi->s_sb;
3664         struct ext4_super_block *es = sbi->s_es;
3665
3666         if (es->s_error_count)
3667                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3668                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3669                          le32_to_cpu(es->s_error_count));
3670         if (es->s_first_error_time) {
3671                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3672                        sb->s_id,
3673                        ext4_get_tstamp(es, s_first_error_time),
3674                        (int) sizeof(es->s_first_error_func),
3675                        es->s_first_error_func,
3676                        le32_to_cpu(es->s_first_error_line));
3677                 if (es->s_first_error_ino)
3678                         printk(KERN_CONT ": inode %u",
3679                                le32_to_cpu(es->s_first_error_ino));
3680                 if (es->s_first_error_block)
3681                         printk(KERN_CONT ": block %llu", (unsigned long long)
3682                                le64_to_cpu(es->s_first_error_block));
3683                 printk(KERN_CONT "\n");
3684         }
3685         if (es->s_last_error_time) {
3686                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3687                        sb->s_id,
3688                        ext4_get_tstamp(es, s_last_error_time),
3689                        (int) sizeof(es->s_last_error_func),
3690                        es->s_last_error_func,
3691                        le32_to_cpu(es->s_last_error_line));
3692                 if (es->s_last_error_ino)
3693                         printk(KERN_CONT ": inode %u",
3694                                le32_to_cpu(es->s_last_error_ino));
3695                 if (es->s_last_error_block)
3696                         printk(KERN_CONT ": block %llu", (unsigned long long)
3697                                le64_to_cpu(es->s_last_error_block));
3698                 printk(KERN_CONT "\n");
3699         }
3700         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3701 }
3702
3703 /* Find next suitable group and run ext4_init_inode_table */
3704 static int ext4_run_li_request(struct ext4_li_request *elr)
3705 {
3706         struct ext4_group_desc *gdp = NULL;
3707         struct super_block *sb = elr->lr_super;
3708         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3709         ext4_group_t group = elr->lr_next_group;
3710         unsigned int prefetch_ios = 0;
3711         int ret = 0;
3712         int nr = EXT4_SB(sb)->s_mb_prefetch;
3713         u64 start_time;
3714
3715         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3716                 elr->lr_next_group = ext4_mb_prefetch(sb, group, nr, &prefetch_ios);
3717                 ext4_mb_prefetch_fini(sb, elr->lr_next_group, nr);
3718                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group, nr);
3719                 if (group >= elr->lr_next_group) {
3720                         ret = 1;
3721                         if (elr->lr_first_not_zeroed != ngroups &&
3722                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3723                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3724                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3725                                 ret = 0;
3726                         }
3727                 }
3728                 return ret;
3729         }
3730
3731         for (; group < ngroups; group++) {
3732                 gdp = ext4_get_group_desc(sb, group, NULL);
3733                 if (!gdp) {
3734                         ret = 1;
3735                         break;
3736                 }
3737
3738                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3739                         break;
3740         }
3741
3742         if (group >= ngroups)
3743                 ret = 1;
3744
3745         if (!ret) {
3746                 start_time = ktime_get_real_ns();
3747                 ret = ext4_init_inode_table(sb, group,
3748                                             elr->lr_timeout ? 0 : 1);
3749                 trace_ext4_lazy_itable_init(sb, group);
3750                 if (elr->lr_timeout == 0) {
3751                         elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3752                                 EXT4_SB(elr->lr_super)->s_li_wait_mult);
3753                 }
3754                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3755                 elr->lr_next_group = group + 1;
3756         }
3757         return ret;
3758 }
3759
3760 /*
3761  * Remove lr_request from the list_request and free the
3762  * request structure. Should be called with li_list_mtx held
3763  */
3764 static void ext4_remove_li_request(struct ext4_li_request *elr)
3765 {
3766         if (!elr)
3767                 return;
3768
3769         list_del(&elr->lr_request);
3770         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3771         kfree(elr);
3772 }
3773
3774 static void ext4_unregister_li_request(struct super_block *sb)
3775 {
3776         mutex_lock(&ext4_li_mtx);
3777         if (!ext4_li_info) {
3778                 mutex_unlock(&ext4_li_mtx);
3779                 return;
3780         }
3781
3782         mutex_lock(&ext4_li_info->li_list_mtx);
3783         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3784         mutex_unlock(&ext4_li_info->li_list_mtx);
3785         mutex_unlock(&ext4_li_mtx);
3786 }
3787
3788 static struct task_struct *ext4_lazyinit_task;
3789
3790 /*
3791  * This is the function where ext4lazyinit thread lives. It walks
3792  * through the request list searching for next scheduled filesystem.
3793  * When such a fs is found, run the lazy initialization request
3794  * (ext4_rn_li_request) and keep track of the time spend in this
3795  * function. Based on that time we compute next schedule time of
3796  * the request. When walking through the list is complete, compute
3797  * next waking time and put itself into sleep.
3798  */
3799 static int ext4_lazyinit_thread(void *arg)
3800 {
3801         struct ext4_lazy_init *eli = arg;
3802         struct list_head *pos, *n;
3803         struct ext4_li_request *elr;
3804         unsigned long next_wakeup, cur;
3805
3806         BUG_ON(NULL == eli);
3807         set_freezable();
3808
3809 cont_thread:
3810         while (true) {
3811                 next_wakeup = MAX_JIFFY_OFFSET;
3812
3813                 mutex_lock(&eli->li_list_mtx);
3814                 if (list_empty(&eli->li_request_list)) {
3815                         mutex_unlock(&eli->li_list_mtx);
3816                         goto exit_thread;
3817                 }
3818                 list_for_each_safe(pos, n, &eli->li_request_list) {
3819                         int err = 0;
3820                         int progress = 0;
3821                         elr = list_entry(pos, struct ext4_li_request,
3822                                          lr_request);
3823
3824                         if (time_before(jiffies, elr->lr_next_sched)) {
3825                                 if (time_before(elr->lr_next_sched, next_wakeup))
3826                                         next_wakeup = elr->lr_next_sched;
3827                                 continue;
3828                         }
3829                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3830                                 if (sb_start_write_trylock(elr->lr_super)) {
3831                                         progress = 1;
3832                                         /*
3833                                          * We hold sb->s_umount, sb can not
3834                                          * be removed from the list, it is
3835                                          * now safe to drop li_list_mtx
3836                                          */
3837                                         mutex_unlock(&eli->li_list_mtx);
3838                                         err = ext4_run_li_request(elr);
3839                                         sb_end_write(elr->lr_super);
3840                                         mutex_lock(&eli->li_list_mtx);
3841                                         n = pos->next;
3842                                 }
3843                                 up_read((&elr->lr_super->s_umount));
3844                         }
3845                         /* error, remove the lazy_init job */
3846                         if (err) {
3847                                 ext4_remove_li_request(elr);
3848                                 continue;
3849                         }
3850                         if (!progress) {
3851                                 elr->lr_next_sched = jiffies +
3852                                         get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3853                         }
3854                         if (time_before(elr->lr_next_sched, next_wakeup))
3855                                 next_wakeup = elr->lr_next_sched;
3856                 }
3857                 mutex_unlock(&eli->li_list_mtx);
3858
3859                 try_to_freeze();
3860
3861                 cur = jiffies;
3862                 if ((time_after_eq(cur, next_wakeup)) ||
3863                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3864                         cond_resched();
3865                         continue;
3866                 }
3867
3868                 schedule_timeout_interruptible(next_wakeup - cur);
3869
3870                 if (kthread_should_stop()) {
3871                         ext4_clear_request_list();
3872                         goto exit_thread;
3873                 }
3874         }
3875
3876 exit_thread:
3877         /*
3878          * It looks like the request list is empty, but we need
3879          * to check it under the li_list_mtx lock, to prevent any
3880          * additions into it, and of course we should lock ext4_li_mtx
3881          * to atomically free the list and ext4_li_info, because at
3882          * this point another ext4 filesystem could be registering
3883          * new one.
3884          */
3885         mutex_lock(&ext4_li_mtx);
3886         mutex_lock(&eli->li_list_mtx);
3887         if (!list_empty(&eli->li_request_list)) {
3888                 mutex_unlock(&eli->li_list_mtx);
3889                 mutex_unlock(&ext4_li_mtx);
3890                 goto cont_thread;
3891         }
3892         mutex_unlock(&eli->li_list_mtx);
3893         kfree(ext4_li_info);
3894         ext4_li_info = NULL;
3895         mutex_unlock(&ext4_li_mtx);
3896
3897         return 0;
3898 }
3899
3900 static void ext4_clear_request_list(void)
3901 {
3902         struct list_head *pos, *n;
3903         struct ext4_li_request *elr;
3904
3905         mutex_lock(&ext4_li_info->li_list_mtx);
3906         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3907                 elr = list_entry(pos, struct ext4_li_request,
3908                                  lr_request);
3909                 ext4_remove_li_request(elr);
3910         }
3911         mutex_unlock(&ext4_li_info->li_list_mtx);
3912 }
3913
3914 static int ext4_run_lazyinit_thread(void)
3915 {
3916         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3917                                          ext4_li_info, "ext4lazyinit");
3918         if (IS_ERR(ext4_lazyinit_task)) {
3919                 int err = PTR_ERR(ext4_lazyinit_task);
3920                 ext4_clear_request_list();
3921                 kfree(ext4_li_info);
3922                 ext4_li_info = NULL;
3923                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3924                                  "initialization thread\n",
3925                                  err);
3926                 return err;
3927         }
3928         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3929         return 0;
3930 }
3931
3932 /*
3933  * Check whether it make sense to run itable init. thread or not.
3934  * If there is at least one uninitialized inode table, return
3935  * corresponding group number, else the loop goes through all
3936  * groups and return total number of groups.
3937  */
3938 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3939 {
3940         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3941         struct ext4_group_desc *gdp = NULL;
3942
3943         if (!ext4_has_group_desc_csum(sb))
3944                 return ngroups;
3945
3946         for (group = 0; group < ngroups; group++) {
3947                 gdp = ext4_get_group_desc(sb, group, NULL);
3948                 if (!gdp)
3949                         continue;
3950
3951                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3952                         break;
3953         }
3954
3955         return group;
3956 }
3957
3958 static int ext4_li_info_new(void)
3959 {
3960         struct ext4_lazy_init *eli = NULL;
3961
3962         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3963         if (!eli)
3964                 return -ENOMEM;
3965
3966         INIT_LIST_HEAD(&eli->li_request_list);
3967         mutex_init(&eli->li_list_mtx);
3968
3969         eli->li_state |= EXT4_LAZYINIT_QUIT;
3970
3971         ext4_li_info = eli;
3972
3973         return 0;
3974 }
3975
3976 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3977                                             ext4_group_t start)
3978 {
3979         struct ext4_li_request *elr;
3980
3981         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3982         if (!elr)
3983                 return NULL;
3984
3985         elr->lr_super = sb;
3986         elr->lr_first_not_zeroed = start;
3987         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3988                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3989                 elr->lr_next_group = start;
3990         } else {
3991                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3992         }
3993
3994         /*
3995          * Randomize first schedule time of the request to
3996          * spread the inode table initialization requests
3997          * better.
3998          */
3999         elr->lr_next_sched = jiffies + get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
4000         return elr;
4001 }
4002
4003 int ext4_register_li_request(struct super_block *sb,
4004                              ext4_group_t first_not_zeroed)
4005 {
4006         struct ext4_sb_info *sbi = EXT4_SB(sb);
4007         struct ext4_li_request *elr = NULL;
4008         ext4_group_t ngroups = sbi->s_groups_count;
4009         int ret = 0;
4010
4011         mutex_lock(&ext4_li_mtx);
4012         if (sbi->s_li_request != NULL) {
4013                 /*
4014                  * Reset timeout so it can be computed again, because
4015                  * s_li_wait_mult might have changed.
4016                  */
4017                 sbi->s_li_request->lr_timeout = 0;
4018                 goto out;
4019         }
4020
4021         if (sb_rdonly(sb) ||
4022             (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
4023              (first_not_zeroed == ngroups || !test_opt(sb, INIT_INODE_TABLE))))
4024                 goto out;
4025
4026         elr = ext4_li_request_new(sb, first_not_zeroed);
4027         if (!elr) {
4028                 ret = -ENOMEM;
4029                 goto out;
4030         }
4031
4032         if (NULL == ext4_li_info) {
4033                 ret = ext4_li_info_new();
4034                 if (ret)
4035                         goto out;
4036         }
4037
4038         mutex_lock(&ext4_li_info->li_list_mtx);
4039         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
4040         mutex_unlock(&ext4_li_info->li_list_mtx);
4041
4042         sbi->s_li_request = elr;
4043         /*
4044          * set elr to NULL here since it has been inserted to
4045          * the request_list and the removal and free of it is
4046          * handled by ext4_clear_request_list from now on.
4047          */
4048         elr = NULL;
4049
4050         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
4051                 ret = ext4_run_lazyinit_thread();
4052                 if (ret)
4053                         goto out;
4054         }
4055 out:
4056         mutex_unlock(&ext4_li_mtx);
4057         if (ret)
4058                 kfree(elr);
4059         return ret;
4060 }
4061
4062 /*
4063  * We do not need to lock anything since this is called on
4064  * module unload.
4065  */
4066 static void ext4_destroy_lazyinit_thread(void)
4067 {
4068         /*
4069          * If thread exited earlier
4070          * there's nothing to be done.
4071          */
4072         if (!ext4_li_info || !ext4_lazyinit_task)
4073                 return;
4074
4075         kthread_stop(ext4_lazyinit_task);
4076 }
4077
4078 static int set_journal_csum_feature_set(struct super_block *sb)
4079 {
4080         int ret = 1;
4081         int compat, incompat;
4082         struct ext4_sb_info *sbi = EXT4_SB(sb);
4083
4084         if (ext4_has_metadata_csum(sb)) {
4085                 /* journal checksum v3 */
4086                 compat = 0;
4087                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4088         } else {
4089                 /* journal checksum v1 */
4090                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4091                 incompat = 0;
4092         }
4093
4094         jbd2_journal_clear_features(sbi->s_journal,
4095                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4096                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4097                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
4098         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4099                 ret = jbd2_journal_set_features(sbi->s_journal,
4100                                 compat, 0,
4101                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4102                                 incompat);
4103         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4104                 ret = jbd2_journal_set_features(sbi->s_journal,
4105                                 compat, 0,
4106                                 incompat);
4107                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4108                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4109         } else {
4110                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4111                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4112         }
4113
4114         return ret;
4115 }
4116
4117 /*
4118  * Note: calculating the overhead so we can be compatible with
4119  * historical BSD practice is quite difficult in the face of
4120  * clusters/bigalloc.  This is because multiple metadata blocks from
4121  * different block group can end up in the same allocation cluster.
4122  * Calculating the exact overhead in the face of clustered allocation
4123  * requires either O(all block bitmaps) in memory or O(number of block
4124  * groups**2) in time.  We will still calculate the superblock for
4125  * older file systems --- and if we come across with a bigalloc file
4126  * system with zero in s_overhead_clusters the estimate will be close to
4127  * correct especially for very large cluster sizes --- but for newer
4128  * file systems, it's better to calculate this figure once at mkfs
4129  * time, and store it in the superblock.  If the superblock value is
4130  * present (even for non-bigalloc file systems), we will use it.
4131  */
4132 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4133                           char *buf)
4134 {
4135         struct ext4_sb_info     *sbi = EXT4_SB(sb);
4136         struct ext4_group_desc  *gdp;
4137         ext4_fsblk_t            first_block, last_block, b;
4138         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
4139         int                     s, j, count = 0;
4140         int                     has_super = ext4_bg_has_super(sb, grp);
4141
4142         if (!ext4_has_feature_bigalloc(sb))
4143                 return (has_super + ext4_bg_num_gdb(sb, grp) +
4144                         (has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
4145                         sbi->s_itb_per_group + 2);
4146
4147         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4148                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
4149         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4150         for (i = 0; i < ngroups; i++) {
4151                 gdp = ext4_get_group_desc(sb, i, NULL);
4152                 b = ext4_block_bitmap(sb, gdp);
4153                 if (b >= first_block && b <= last_block) {
4154                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4155                         count++;
4156                 }
4157                 b = ext4_inode_bitmap(sb, gdp);
4158                 if (b >= first_block && b <= last_block) {
4159                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4160                         count++;
4161                 }
4162                 b = ext4_inode_table(sb, gdp);
4163                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4164                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4165                                 int c = EXT4_B2C(sbi, b - first_block);
4166                                 ext4_set_bit(c, buf);
4167                                 count++;
4168                         }
4169                 if (i != grp)
4170                         continue;
4171                 s = 0;
4172                 if (ext4_bg_has_super(sb, grp)) {
4173                         ext4_set_bit(s++, buf);
4174                         count++;
4175                 }
4176                 j = ext4_bg_num_gdb(sb, grp);
4177                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4178                         ext4_error(sb, "Invalid number of block group "
4179                                    "descriptor blocks: %d", j);
4180                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4181                 }
4182                 count += j;
4183                 for (; j > 0; j--)
4184                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4185         }
4186         if (!count)
4187                 return 0;
4188         return EXT4_CLUSTERS_PER_GROUP(sb) -
4189                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4190 }
4191
4192 /*
4193  * Compute the overhead and stash it in sbi->s_overhead
4194  */
4195 int ext4_calculate_overhead(struct super_block *sb)
4196 {
4197         struct ext4_sb_info *sbi = EXT4_SB(sb);
4198         struct ext4_super_block *es = sbi->s_es;
4199         struct inode *j_inode;
4200         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4201         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4202         ext4_fsblk_t overhead = 0;
4203         char *buf = (char *) get_zeroed_page(GFP_NOFS);
4204
4205         if (!buf)
4206                 return -ENOMEM;
4207
4208         /*
4209          * Compute the overhead (FS structures).  This is constant
4210          * for a given filesystem unless the number of block groups
4211          * changes so we cache the previous value until it does.
4212          */
4213
4214         /*
4215          * All of the blocks before first_data_block are overhead
4216          */
4217         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4218
4219         /*
4220          * Add the overhead found in each block group
4221          */
4222         for (i = 0; i < ngroups; i++) {
4223                 int blks;
4224
4225                 blks = count_overhead(sb, i, buf);
4226                 overhead += blks;
4227                 if (blks)
4228                         memset(buf, 0, PAGE_SIZE);
4229                 cond_resched();
4230         }
4231
4232         /*
4233          * Add the internal journal blocks whether the journal has been
4234          * loaded or not
4235          */
4236         if (sbi->s_journal && !sbi->s_journal_bdev_handle)
4237                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4238         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4239                 /* j_inum for internal journal is non-zero */
4240                 j_inode = ext4_get_journal_inode(sb, j_inum);
4241                 if (!IS_ERR(j_inode)) {
4242                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4243                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
4244                         iput(j_inode);
4245                 } else {
4246                         ext4_msg(sb, KERN_ERR, "can't get journal size");
4247                 }
4248         }
4249         sbi->s_overhead = overhead;
4250         smp_wmb();
4251         free_page((unsigned long) buf);
4252         return 0;
4253 }
4254
4255 static void ext4_set_resv_clusters(struct super_block *sb)
4256 {
4257         ext4_fsblk_t resv_clusters;
4258         struct ext4_sb_info *sbi = EXT4_SB(sb);
4259
4260         /*
4261          * There's no need to reserve anything when we aren't using extents.
4262          * The space estimates are exact, there are no unwritten extents,
4263          * hole punching doesn't need new metadata... This is needed especially
4264          * to keep ext2/3 backward compatibility.
4265          */
4266         if (!ext4_has_feature_extents(sb))
4267                 return;
4268         /*
4269          * By default we reserve 2% or 4096 clusters, whichever is smaller.
4270          * This should cover the situations where we can not afford to run
4271          * out of space like for example punch hole, or converting
4272          * unwritten extents in delalloc path. In most cases such
4273          * allocation would require 1, or 2 blocks, higher numbers are
4274          * very rare.
4275          */
4276         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4277                          sbi->s_cluster_bits);
4278
4279         do_div(resv_clusters, 50);
4280         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4281
4282         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4283 }
4284
4285 static const char *ext4_quota_mode(struct super_block *sb)
4286 {
4287 #ifdef CONFIG_QUOTA
4288         if (!ext4_quota_capable(sb))
4289                 return "none";
4290
4291         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4292                 return "journalled";
4293         else
4294                 return "writeback";
4295 #else
4296         return "disabled";
4297 #endif
4298 }
4299
4300 static void ext4_setup_csum_trigger(struct super_block *sb,
4301                                     enum ext4_journal_trigger_type type,
4302                                     void (*trigger)(
4303                                         struct jbd2_buffer_trigger_type *type,
4304                                         struct buffer_head *bh,
4305                                         void *mapped_data,
4306                                         size_t size))
4307 {
4308         struct ext4_sb_info *sbi = EXT4_SB(sb);
4309
4310         sbi->s_journal_triggers[type].sb = sb;
4311         sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4312 }
4313
4314 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4315 {
4316         if (!sbi)
4317                 return;
4318
4319         kfree(sbi->s_blockgroup_lock);
4320         fs_put_dax(sbi->s_daxdev, NULL);
4321         kfree(sbi);
4322 }
4323
4324 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4325 {
4326         struct ext4_sb_info *sbi;
4327
4328         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4329         if (!sbi)
4330                 return NULL;
4331
4332         sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
4333                                            NULL, NULL);
4334
4335         sbi->s_blockgroup_lock =
4336                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4337
4338         if (!sbi->s_blockgroup_lock)
4339                 goto err_out;
4340
4341         sb->s_fs_info = sbi;
4342         sbi->s_sb = sb;
4343         return sbi;
4344 err_out:
4345         fs_put_dax(sbi->s_daxdev, NULL);
4346         kfree(sbi);
4347         return NULL;
4348 }
4349
4350 static void ext4_set_def_opts(struct super_block *sb,
4351                               struct ext4_super_block *es)
4352 {
4353         unsigned long def_mount_opts;
4354
4355         /* Set defaults before we parse the mount options */
4356         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4357         set_opt(sb, INIT_INODE_TABLE);
4358         if (def_mount_opts & EXT4_DEFM_DEBUG)
4359                 set_opt(sb, DEBUG);
4360         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4361                 set_opt(sb, GRPID);
4362         if (def_mount_opts & EXT4_DEFM_UID16)
4363                 set_opt(sb, NO_UID32);
4364         /* xattr user namespace & acls are now defaulted on */
4365         set_opt(sb, XATTR_USER);
4366 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4367         set_opt(sb, POSIX_ACL);
4368 #endif
4369         if (ext4_has_feature_fast_commit(sb))
4370                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4371         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4372         if (ext4_has_metadata_csum(sb))
4373                 set_opt(sb, JOURNAL_CHECKSUM);
4374
4375         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4376                 set_opt(sb, JOURNAL_DATA);
4377         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4378                 set_opt(sb, ORDERED_DATA);
4379         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4380                 set_opt(sb, WRITEBACK_DATA);
4381
4382         if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_PANIC)
4383                 set_opt(sb, ERRORS_PANIC);
4384         else if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_CONTINUE)
4385                 set_opt(sb, ERRORS_CONT);
4386         else
4387                 set_opt(sb, ERRORS_RO);
4388         /* block_validity enabled by default; disable with noblock_validity */
4389         set_opt(sb, BLOCK_VALIDITY);
4390         if (def_mount_opts & EXT4_DEFM_DISCARD)
4391                 set_opt(sb, DISCARD);
4392
4393         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4394                 set_opt(sb, BARRIER);
4395
4396         /*
4397          * enable delayed allocation by default
4398          * Use -o nodelalloc to turn it off
4399          */
4400         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4401             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4402                 set_opt(sb, DELALLOC);
4403
4404         if (sb->s_blocksize <= PAGE_SIZE)
4405                 set_opt(sb, DIOREAD_NOLOCK);
4406 }
4407
4408 static int ext4_handle_clustersize(struct super_block *sb)
4409 {
4410         struct ext4_sb_info *sbi = EXT4_SB(sb);
4411         struct ext4_super_block *es = sbi->s_es;
4412         int clustersize;
4413
4414         /* Handle clustersize */
4415         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4416         if (ext4_has_feature_bigalloc(sb)) {
4417                 if (clustersize < sb->s_blocksize) {
4418                         ext4_msg(sb, KERN_ERR,
4419                                  "cluster size (%d) smaller than "
4420                                  "block size (%lu)", clustersize, sb->s_blocksize);
4421                         return -EINVAL;
4422                 }
4423                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4424                         le32_to_cpu(es->s_log_block_size);
4425                 sbi->s_clusters_per_group =
4426                         le32_to_cpu(es->s_clusters_per_group);
4427                 if (sbi->s_clusters_per_group > sb->s_blocksize * 8) {
4428                         ext4_msg(sb, KERN_ERR,
4429                                  "#clusters per group too big: %lu",
4430                                  sbi->s_clusters_per_group);
4431                         return -EINVAL;
4432                 }
4433                 if (sbi->s_blocks_per_group !=
4434                     (sbi->s_clusters_per_group * (clustersize / sb->s_blocksize))) {
4435                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4436                                  "clusters per group (%lu) inconsistent",
4437                                  sbi->s_blocks_per_group,
4438                                  sbi->s_clusters_per_group);
4439                         return -EINVAL;
4440                 }
4441         } else {
4442                 if (clustersize != sb->s_blocksize) {
4443                         ext4_msg(sb, KERN_ERR,
4444                                  "fragment/cluster size (%d) != "
4445                                  "block size (%lu)", clustersize, sb->s_blocksize);
4446                         return -EINVAL;
4447                 }
4448                 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
4449                         ext4_msg(sb, KERN_ERR,
4450                                  "#blocks per group too big: %lu",
4451                                  sbi->s_blocks_per_group);
4452                         return -EINVAL;
4453                 }
4454                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4455                 sbi->s_cluster_bits = 0;
4456         }
4457         sbi->s_cluster_ratio = clustersize / sb->s_blocksize;
4458
4459         /* Do we have standard group size of clustersize * 8 blocks ? */
4460         if (sbi->s_blocks_per_group == clustersize << 3)
4461                 set_opt2(sb, STD_GROUP_SIZE);
4462
4463         return 0;
4464 }
4465
4466 static void ext4_fast_commit_init(struct super_block *sb)
4467 {
4468         struct ext4_sb_info *sbi = EXT4_SB(sb);
4469
4470         /* Initialize fast commit stuff */
4471         atomic_set(&sbi->s_fc_subtid, 0);
4472         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4473         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4474         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4475         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4476         sbi->s_fc_bytes = 0;
4477         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4478         sbi->s_fc_ineligible_tid = 0;
4479         spin_lock_init(&sbi->s_fc_lock);
4480         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4481         sbi->s_fc_replay_state.fc_regions = NULL;
4482         sbi->s_fc_replay_state.fc_regions_size = 0;
4483         sbi->s_fc_replay_state.fc_regions_used = 0;
4484         sbi->s_fc_replay_state.fc_regions_valid = 0;
4485         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4486         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4487         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4488 }
4489
4490 static int ext4_inode_info_init(struct super_block *sb,
4491                                 struct ext4_super_block *es)
4492 {
4493         struct ext4_sb_info *sbi = EXT4_SB(sb);
4494
4495         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4496                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4497                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4498         } else {
4499                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4500                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4501                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4502                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4503                                  sbi->s_first_ino);
4504                         return -EINVAL;
4505                 }
4506                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4507                     (!is_power_of_2(sbi->s_inode_size)) ||
4508                     (sbi->s_inode_size > sb->s_blocksize)) {
4509                         ext4_msg(sb, KERN_ERR,
4510                                "unsupported inode size: %d",
4511                                sbi->s_inode_size);
4512                         ext4_msg(sb, KERN_ERR, "blocksize: %lu", sb->s_blocksize);
4513                         return -EINVAL;
4514                 }
4515                 /*
4516                  * i_atime_extra is the last extra field available for
4517                  * [acm]times in struct ext4_inode. Checking for that
4518                  * field should suffice to ensure we have extra space
4519                  * for all three.
4520                  */
4521                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4522                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4523                         sb->s_time_gran = 1;
4524                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4525                 } else {
4526                         sb->s_time_gran = NSEC_PER_SEC;
4527                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4528                 }
4529                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4530         }
4531
4532         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4533                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4534                         EXT4_GOOD_OLD_INODE_SIZE;
4535                 if (ext4_has_feature_extra_isize(sb)) {
4536                         unsigned v, max = (sbi->s_inode_size -
4537                                            EXT4_GOOD_OLD_INODE_SIZE);
4538
4539                         v = le16_to_cpu(es->s_want_extra_isize);
4540                         if (v > max) {
4541                                 ext4_msg(sb, KERN_ERR,
4542                                          "bad s_want_extra_isize: %d", v);
4543                                 return -EINVAL;
4544                         }
4545                         if (sbi->s_want_extra_isize < v)
4546                                 sbi->s_want_extra_isize = v;
4547
4548                         v = le16_to_cpu(es->s_min_extra_isize);
4549                         if (v > max) {
4550                                 ext4_msg(sb, KERN_ERR,
4551                                          "bad s_min_extra_isize: %d", v);
4552                                 return -EINVAL;
4553                         }
4554                         if (sbi->s_want_extra_isize < v)
4555                                 sbi->s_want_extra_isize = v;
4556                 }
4557         }
4558
4559         return 0;
4560 }
4561
4562 #if IS_ENABLED(CONFIG_UNICODE)
4563 static int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4564 {
4565         const struct ext4_sb_encodings *encoding_info;
4566         struct unicode_map *encoding;
4567         __u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4568
4569         if (!ext4_has_feature_casefold(sb) || sb->s_encoding)
4570                 return 0;
4571
4572         encoding_info = ext4_sb_read_encoding(es);
4573         if (!encoding_info) {
4574                 ext4_msg(sb, KERN_ERR,
4575                         "Encoding requested by superblock is unknown");
4576                 return -EINVAL;
4577         }
4578
4579         encoding = utf8_load(encoding_info->version);
4580         if (IS_ERR(encoding)) {
4581                 ext4_msg(sb, KERN_ERR,
4582                         "can't mount with superblock charset: %s-%u.%u.%u "
4583                         "not supported by the kernel. flags: 0x%x.",
4584                         encoding_info->name,
4585                         unicode_major(encoding_info->version),
4586                         unicode_minor(encoding_info->version),
4587                         unicode_rev(encoding_info->version),
4588                         encoding_flags);
4589                 return -EINVAL;
4590         }
4591         ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4592                 "%s-%u.%u.%u with flags 0x%hx", 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
4598         sb->s_encoding = encoding;
4599         sb->s_encoding_flags = encoding_flags;
4600
4601         return 0;
4602 }
4603 #else
4604 static inline int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4605 {
4606         return 0;
4607 }
4608 #endif
4609
4610 static int ext4_init_metadata_csum(struct super_block *sb, struct ext4_super_block *es)
4611 {
4612         struct ext4_sb_info *sbi = EXT4_SB(sb);
4613
4614         /* Warn if metadata_csum and gdt_csum are both set. */
4615         if (ext4_has_feature_metadata_csum(sb) &&
4616             ext4_has_feature_gdt_csum(sb))
4617                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4618                              "redundant flags; please run fsck.");
4619
4620         /* Check for a known checksum algorithm */
4621         if (!ext4_verify_csum_type(sb, es)) {
4622                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4623                          "unknown checksum algorithm.");
4624                 return -EINVAL;
4625         }
4626         ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4627                                 ext4_orphan_file_block_trigger);
4628
4629         /* Load the checksum driver */
4630         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4631         if (IS_ERR(sbi->s_chksum_driver)) {
4632                 int ret = PTR_ERR(sbi->s_chksum_driver);
4633                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4634                 sbi->s_chksum_driver = NULL;
4635                 return ret;
4636         }
4637
4638         /* Check superblock checksum */
4639         if (!ext4_superblock_csum_verify(sb, es)) {
4640                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4641                          "invalid superblock checksum.  Run e2fsck?");
4642                 return -EFSBADCRC;
4643         }
4644
4645         /* Precompute checksum seed for all metadata */
4646         if (ext4_has_feature_csum_seed(sb))
4647                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4648         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4649                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4650                                                sizeof(es->s_uuid));
4651         return 0;
4652 }
4653
4654 static int ext4_check_feature_compatibility(struct super_block *sb,
4655                                             struct ext4_super_block *es,
4656                                             int silent)
4657 {
4658         struct ext4_sb_info *sbi = EXT4_SB(sb);
4659
4660         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4661             (ext4_has_compat_features(sb) ||
4662              ext4_has_ro_compat_features(sb) ||
4663              ext4_has_incompat_features(sb)))
4664                 ext4_msg(sb, KERN_WARNING,
4665                        "feature flags set on rev 0 fs, "
4666                        "running e2fsck is recommended");
4667
4668         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4669                 set_opt2(sb, HURD_COMPAT);
4670                 if (ext4_has_feature_64bit(sb)) {
4671                         ext4_msg(sb, KERN_ERR,
4672                                  "The Hurd can't support 64-bit file systems");
4673                         return -EINVAL;
4674                 }
4675
4676                 /*
4677                  * ea_inode feature uses l_i_version field which is not
4678                  * available in HURD_COMPAT mode.
4679                  */
4680                 if (ext4_has_feature_ea_inode(sb)) {
4681                         ext4_msg(sb, KERN_ERR,
4682                                  "ea_inode feature is not supported for Hurd");
4683                         return -EINVAL;
4684                 }
4685         }
4686
4687         if (IS_EXT2_SB(sb)) {
4688                 if (ext2_feature_set_ok(sb))
4689                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4690                                  "using the ext4 subsystem");
4691                 else {
4692                         /*
4693                          * If we're probing be silent, if this looks like
4694                          * it's actually an ext[34] filesystem.
4695                          */
4696                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4697                                 return -EINVAL;
4698                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4699                                  "to feature incompatibilities");
4700                         return -EINVAL;
4701                 }
4702         }
4703
4704         if (IS_EXT3_SB(sb)) {
4705                 if (ext3_feature_set_ok(sb))
4706                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4707                                  "using the ext4 subsystem");
4708                 else {
4709                         /*
4710                          * If we're probing be silent, if this looks like
4711                          * it's actually an ext4 filesystem.
4712                          */
4713                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4714                                 return -EINVAL;
4715                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4716                                  "to feature incompatibilities");
4717                         return -EINVAL;
4718                 }
4719         }
4720
4721         /*
4722          * Check feature flags regardless of the revision level, since we
4723          * previously didn't change the revision level when setting the flags,
4724          * so there is a chance incompat flags are set on a rev 0 filesystem.
4725          */
4726         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4727                 return -EINVAL;
4728
4729         if (sbi->s_daxdev) {
4730                 if (sb->s_blocksize == PAGE_SIZE)
4731                         set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4732                 else
4733                         ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
4734         }
4735
4736         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4737                 if (ext4_has_feature_inline_data(sb)) {
4738                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4739                                         " that may contain inline data");
4740                         return -EINVAL;
4741                 }
4742                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4743                         ext4_msg(sb, KERN_ERR,
4744                                 "DAX unsupported by block device.");
4745                         return -EINVAL;
4746                 }
4747         }
4748
4749         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4750                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4751                          es->s_encryption_level);
4752                 return -EINVAL;
4753         }
4754
4755         return 0;
4756 }
4757
4758 static int ext4_check_geometry(struct super_block *sb,
4759                                struct ext4_super_block *es)
4760 {
4761         struct ext4_sb_info *sbi = EXT4_SB(sb);
4762         __u64 blocks_count;
4763         int err;
4764
4765         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (sb->s_blocksize / 4)) {
4766                 ext4_msg(sb, KERN_ERR,
4767                          "Number of reserved GDT blocks insanely large: %d",
4768                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4769                 return -EINVAL;
4770         }
4771         /*
4772          * Test whether we have more sectors than will fit in sector_t,
4773          * and whether the max offset is addressable by the page cache.
4774          */
4775         err = generic_check_addressable(sb->s_blocksize_bits,
4776                                         ext4_blocks_count(es));
4777         if (err) {
4778                 ext4_msg(sb, KERN_ERR, "filesystem"
4779                          " too large to mount safely on this system");
4780                 return err;
4781         }
4782
4783         /* check blocks count against device size */
4784         blocks_count = sb_bdev_nr_blocks(sb);
4785         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4786                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4787                        "exceeds size of device (%llu blocks)",
4788                        ext4_blocks_count(es), blocks_count);
4789                 return -EINVAL;
4790         }
4791
4792         /*
4793          * It makes no sense for the first data block to be beyond the end
4794          * of the filesystem.
4795          */
4796         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4797                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4798                          "block %u is beyond end of filesystem (%llu)",
4799                          le32_to_cpu(es->s_first_data_block),
4800                          ext4_blocks_count(es));
4801                 return -EINVAL;
4802         }
4803         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4804             (sbi->s_cluster_ratio == 1)) {
4805                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4806                          "block is 0 with a 1k block and cluster size");
4807                 return -EINVAL;
4808         }
4809
4810         blocks_count = (ext4_blocks_count(es) -
4811                         le32_to_cpu(es->s_first_data_block) +
4812                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4813         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4814         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4815                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4816                        "(block count %llu, first data block %u, "
4817                        "blocks per group %lu)", blocks_count,
4818                        ext4_blocks_count(es),
4819                        le32_to_cpu(es->s_first_data_block),
4820                        EXT4_BLOCKS_PER_GROUP(sb));
4821                 return -EINVAL;
4822         }
4823         sbi->s_groups_count = blocks_count;
4824         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4825                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4826         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4827             le32_to_cpu(es->s_inodes_count)) {
4828                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4829                          le32_to_cpu(es->s_inodes_count),
4830                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4831                 return -EINVAL;
4832         }
4833
4834         return 0;
4835 }
4836
4837 static int ext4_group_desc_init(struct super_block *sb,
4838                                 struct ext4_super_block *es,
4839                                 ext4_fsblk_t logical_sb_block,
4840                                 ext4_group_t *first_not_zeroed)
4841 {
4842         struct ext4_sb_info *sbi = EXT4_SB(sb);
4843         unsigned int db_count;
4844         ext4_fsblk_t block;
4845         int i;
4846
4847         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4848                    EXT4_DESC_PER_BLOCK(sb);
4849         if (ext4_has_feature_meta_bg(sb)) {
4850                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4851                         ext4_msg(sb, KERN_WARNING,
4852                                  "first meta block group too large: %u "
4853                                  "(group descriptor block count %u)",
4854                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4855                         return -EINVAL;
4856                 }
4857         }
4858         rcu_assign_pointer(sbi->s_group_desc,
4859                            kvmalloc_array(db_count,
4860                                           sizeof(struct buffer_head *),
4861                                           GFP_KERNEL));
4862         if (sbi->s_group_desc == NULL) {
4863                 ext4_msg(sb, KERN_ERR, "not enough memory");
4864                 return -ENOMEM;
4865         }
4866
4867         bgl_lock_init(sbi->s_blockgroup_lock);
4868
4869         /* Pre-read the descriptors into the buffer cache */
4870         for (i = 0; i < db_count; i++) {
4871                 block = descriptor_loc(sb, logical_sb_block, i);
4872                 ext4_sb_breadahead_unmovable(sb, block);
4873         }
4874
4875         for (i = 0; i < db_count; i++) {
4876                 struct buffer_head *bh;
4877
4878                 block = descriptor_loc(sb, logical_sb_block, i);
4879                 bh = ext4_sb_bread_unmovable(sb, block);
4880                 if (IS_ERR(bh)) {
4881                         ext4_msg(sb, KERN_ERR,
4882                                "can't read group descriptor %d", i);
4883                         sbi->s_gdb_count = i;
4884                         return PTR_ERR(bh);
4885                 }
4886                 rcu_read_lock();
4887                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4888                 rcu_read_unlock();
4889         }
4890         sbi->s_gdb_count = db_count;
4891         if (!ext4_check_descriptors(sb, logical_sb_block, first_not_zeroed)) {
4892                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4893                 return -EFSCORRUPTED;
4894         }
4895
4896         return 0;
4897 }
4898
4899 static int ext4_load_and_init_journal(struct super_block *sb,
4900                                       struct ext4_super_block *es,
4901                                       struct ext4_fs_context *ctx)
4902 {
4903         struct ext4_sb_info *sbi = EXT4_SB(sb);
4904         int err;
4905
4906         err = ext4_load_journal(sb, es, ctx->journal_devnum);
4907         if (err)
4908                 return err;
4909
4910         if (ext4_has_feature_64bit(sb) &&
4911             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4912                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4913                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4914                 goto out;
4915         }
4916
4917         if (!set_journal_csum_feature_set(sb)) {
4918                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4919                          "feature set");
4920                 goto out;
4921         }
4922
4923         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4924                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4925                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4926                 ext4_msg(sb, KERN_ERR,
4927                         "Failed to set fast commit journal feature");
4928                 goto out;
4929         }
4930
4931         /* We have now updated the journal if required, so we can
4932          * validate the data journaling mode. */
4933         switch (test_opt(sb, DATA_FLAGS)) {
4934         case 0:
4935                 /* No mode set, assume a default based on the journal
4936                  * capabilities: ORDERED_DATA if the journal can
4937                  * cope, else JOURNAL_DATA
4938                  */
4939                 if (jbd2_journal_check_available_features
4940                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4941                         set_opt(sb, ORDERED_DATA);
4942                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4943                 } else {
4944                         set_opt(sb, JOURNAL_DATA);
4945                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4946                 }
4947                 break;
4948
4949         case EXT4_MOUNT_ORDERED_DATA:
4950         case EXT4_MOUNT_WRITEBACK_DATA:
4951                 if (!jbd2_journal_check_available_features
4952                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4953                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4954                                "requested data journaling mode");
4955                         goto out;
4956                 }
4957                 break;
4958         default:
4959                 break;
4960         }
4961
4962         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4963             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4964                 ext4_msg(sb, KERN_ERR, "can't mount with "
4965                         "journal_async_commit in data=ordered mode");
4966                 goto out;
4967         }
4968
4969         set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
4970
4971         sbi->s_journal->j_submit_inode_data_buffers =
4972                 ext4_journal_submit_inode_data_buffers;
4973         sbi->s_journal->j_finish_inode_data_buffers =
4974                 ext4_journal_finish_inode_data_buffers;
4975
4976         return 0;
4977
4978 out:
4979         /* flush s_sb_upd_work before destroying the journal. */
4980         flush_work(&sbi->s_sb_upd_work);
4981         jbd2_journal_destroy(sbi->s_journal);
4982         sbi->s_journal = NULL;
4983         return -EINVAL;
4984 }
4985
4986 static int ext4_check_journal_data_mode(struct super_block *sb)
4987 {
4988         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4989                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with "
4990                             "data=journal disables delayed allocation, "
4991                             "dioread_nolock, O_DIRECT and fast_commit support!\n");
4992                 /* can't mount with both data=journal and dioread_nolock. */
4993                 clear_opt(sb, DIOREAD_NOLOCK);
4994                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4995                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4996                         ext4_msg(sb, KERN_ERR, "can't mount with "
4997                                  "both data=journal and delalloc");
4998                         return -EINVAL;
4999                 }
5000                 if (test_opt(sb, DAX_ALWAYS)) {
5001                         ext4_msg(sb, KERN_ERR, "can't mount with "
5002                                  "both data=journal and dax");
5003                         return -EINVAL;
5004                 }
5005                 if (ext4_has_feature_encrypt(sb)) {
5006                         ext4_msg(sb, KERN_WARNING,
5007                                  "encrypted files will use data=ordered "
5008                                  "instead of data journaling mode");
5009                 }
5010                 if (test_opt(sb, DELALLOC))
5011                         clear_opt(sb, DELALLOC);
5012         } else {
5013                 sb->s_iflags |= SB_I_CGROUPWB;
5014         }
5015
5016         return 0;
5017 }
5018
5019 static int ext4_load_super(struct super_block *sb, ext4_fsblk_t *lsb,
5020                            int silent)
5021 {
5022         struct ext4_sb_info *sbi = EXT4_SB(sb);
5023         struct ext4_super_block *es;
5024         ext4_fsblk_t logical_sb_block;
5025         unsigned long offset = 0;
5026         struct buffer_head *bh;
5027         int ret = -EINVAL;
5028         int blocksize;
5029
5030         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
5031         if (!blocksize) {
5032                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
5033                 return -EINVAL;
5034         }
5035
5036         /*
5037          * The ext4 superblock will not be buffer aligned for other than 1kB
5038          * block sizes.  We need to calculate the offset from buffer start.
5039          */
5040         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
5041                 logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5042                 offset = do_div(logical_sb_block, blocksize);
5043         } else {
5044                 logical_sb_block = sbi->s_sb_block;
5045         }
5046
5047         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5048         if (IS_ERR(bh)) {
5049                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
5050                 return PTR_ERR(bh);
5051         }
5052         /*
5053          * Note: s_es must be initialized as soon as possible because
5054          *       some ext4 macro-instructions depend on its value
5055          */
5056         es = (struct ext4_super_block *) (bh->b_data + offset);
5057         sbi->s_es = es;
5058         sb->s_magic = le16_to_cpu(es->s_magic);
5059         if (sb->s_magic != EXT4_SUPER_MAGIC) {
5060                 if (!silent)
5061                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5062                 goto out;
5063         }
5064
5065         if (le32_to_cpu(es->s_log_block_size) >
5066             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5067                 ext4_msg(sb, KERN_ERR,
5068                          "Invalid log block size: %u",
5069                          le32_to_cpu(es->s_log_block_size));
5070                 goto out;
5071         }
5072         if (le32_to_cpu(es->s_log_cluster_size) >
5073             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5074                 ext4_msg(sb, KERN_ERR,
5075                          "Invalid log cluster size: %u",
5076                          le32_to_cpu(es->s_log_cluster_size));
5077                 goto out;
5078         }
5079
5080         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
5081
5082         /*
5083          * If the default block size is not the same as the real block size,
5084          * we need to reload it.
5085          */
5086         if (sb->s_blocksize == blocksize) {
5087                 *lsb = logical_sb_block;
5088                 sbi->s_sbh = bh;
5089                 return 0;
5090         }
5091
5092         /*
5093          * bh must be released before kill_bdev(), otherwise
5094          * it won't be freed and its page also. kill_bdev()
5095          * is called by sb_set_blocksize().
5096          */
5097         brelse(bh);
5098         /* Validate the filesystem blocksize */
5099         if (!sb_set_blocksize(sb, blocksize)) {
5100                 ext4_msg(sb, KERN_ERR, "bad block size %d",
5101                                 blocksize);
5102                 bh = NULL;
5103                 goto out;
5104         }
5105
5106         logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5107         offset = do_div(logical_sb_block, blocksize);
5108         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5109         if (IS_ERR(bh)) {
5110                 ext4_msg(sb, KERN_ERR, "Can't read superblock on 2nd try");
5111                 ret = PTR_ERR(bh);
5112                 bh = NULL;
5113                 goto out;
5114         }
5115         es = (struct ext4_super_block *)(bh->b_data + offset);
5116         sbi->s_es = es;
5117         if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
5118                 ext4_msg(sb, KERN_ERR, "Magic mismatch, very weird!");
5119                 goto out;
5120         }
5121         *lsb = logical_sb_block;
5122         sbi->s_sbh = bh;
5123         return 0;
5124 out:
5125         brelse(bh);
5126         return ret;
5127 }
5128
5129 static void ext4_hash_info_init(struct super_block *sb)
5130 {
5131         struct ext4_sb_info *sbi = EXT4_SB(sb);
5132         struct ext4_super_block *es = sbi->s_es;
5133         unsigned int i;
5134
5135         for (i = 0; i < 4; i++)
5136                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
5137
5138         sbi->s_def_hash_version = es->s_def_hash_version;
5139         if (ext4_has_feature_dir_index(sb)) {
5140                 i = le32_to_cpu(es->s_flags);
5141                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
5142                         sbi->s_hash_unsigned = 3;
5143                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
5144 #ifdef __CHAR_UNSIGNED__
5145                         if (!sb_rdonly(sb))
5146                                 es->s_flags |=
5147                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
5148                         sbi->s_hash_unsigned = 3;
5149 #else
5150                         if (!sb_rdonly(sb))
5151                                 es->s_flags |=
5152                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
5153 #endif
5154                 }
5155         }
5156 }
5157
5158 static int ext4_block_group_meta_init(struct super_block *sb, int silent)
5159 {
5160         struct ext4_sb_info *sbi = EXT4_SB(sb);
5161         struct ext4_super_block *es = sbi->s_es;
5162         int has_huge_files;
5163
5164         has_huge_files = ext4_has_feature_huge_file(sb);
5165         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
5166                                                       has_huge_files);
5167         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
5168
5169         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
5170         if (ext4_has_feature_64bit(sb)) {
5171                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
5172                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
5173                     !is_power_of_2(sbi->s_desc_size)) {
5174                         ext4_msg(sb, KERN_ERR,
5175                                "unsupported descriptor size %lu",
5176                                sbi->s_desc_size);
5177                         return -EINVAL;
5178                 }
5179         } else
5180                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
5181
5182         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
5183         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
5184
5185         sbi->s_inodes_per_block = sb->s_blocksize / EXT4_INODE_SIZE(sb);
5186         if (sbi->s_inodes_per_block == 0 || sbi->s_blocks_per_group == 0) {
5187                 if (!silent)
5188                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5189                 return -EINVAL;
5190         }
5191         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
5192             sbi->s_inodes_per_group > sb->s_blocksize * 8) {
5193                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
5194                          sbi->s_inodes_per_group);
5195                 return -EINVAL;
5196         }
5197         sbi->s_itb_per_group = sbi->s_inodes_per_group /
5198                                         sbi->s_inodes_per_block;
5199         sbi->s_desc_per_block = sb->s_blocksize / EXT4_DESC_SIZE(sb);
5200         sbi->s_mount_state = le16_to_cpu(es->s_state) & ~EXT4_FC_REPLAY;
5201         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
5202         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
5203
5204         return 0;
5205 }
5206
5207 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
5208 {
5209         struct ext4_super_block *es = NULL;
5210         struct ext4_sb_info *sbi = EXT4_SB(sb);
5211         ext4_fsblk_t logical_sb_block;
5212         struct inode *root;
5213         int needs_recovery;
5214         int err;
5215         ext4_group_t first_not_zeroed;
5216         struct ext4_fs_context *ctx = fc->fs_private;
5217         int silent = fc->sb_flags & SB_SILENT;
5218
5219         /* Set defaults for the variables that will be set during parsing */
5220         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO))
5221                 ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5222
5223         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
5224         sbi->s_sectors_written_start =
5225                 part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
5226
5227         err = ext4_load_super(sb, &logical_sb_block, silent);
5228         if (err)
5229                 goto out_fail;
5230
5231         es = sbi->s_es;
5232         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
5233
5234         err = ext4_init_metadata_csum(sb, es);
5235         if (err)
5236                 goto failed_mount;
5237
5238         ext4_set_def_opts(sb, es);
5239
5240         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
5241         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
5242         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
5243         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
5244         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
5245
5246         /*
5247          * set default s_li_wait_mult for lazyinit, for the case there is
5248          * no mount option specified.
5249          */
5250         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
5251
5252         err = ext4_inode_info_init(sb, es);
5253         if (err)
5254                 goto failed_mount;
5255
5256         err = parse_apply_sb_mount_options(sb, ctx);
5257         if (err < 0)
5258                 goto failed_mount;
5259
5260         sbi->s_def_mount_opt = sbi->s_mount_opt;
5261         sbi->s_def_mount_opt2 = sbi->s_mount_opt2;
5262
5263         err = ext4_check_opt_consistency(fc, sb);
5264         if (err < 0)
5265                 goto failed_mount;
5266
5267         ext4_apply_options(fc, sb);
5268
5269         err = ext4_encoding_init(sb, es);
5270         if (err)
5271                 goto failed_mount;
5272
5273         err = ext4_check_journal_data_mode(sb);
5274         if (err)
5275                 goto failed_mount;
5276
5277         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5278                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5279
5280         /* i_version is always enabled now */
5281         sb->s_flags |= SB_I_VERSION;
5282
5283         err = ext4_check_feature_compatibility(sb, es, silent);
5284         if (err)
5285                 goto failed_mount;
5286
5287         err = ext4_block_group_meta_init(sb, silent);
5288         if (err)
5289                 goto failed_mount;
5290
5291         ext4_hash_info_init(sb);
5292
5293         err = ext4_handle_clustersize(sb);
5294         if (err)
5295                 goto failed_mount;
5296
5297         err = ext4_check_geometry(sb, es);
5298         if (err)
5299                 goto failed_mount;
5300
5301         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5302         spin_lock_init(&sbi->s_error_lock);
5303         INIT_WORK(&sbi->s_sb_upd_work, update_super_work);
5304
5305         err = ext4_group_desc_init(sb, es, logical_sb_block, &first_not_zeroed);
5306         if (err)
5307                 goto failed_mount3;
5308
5309         err = ext4_es_register_shrinker(sbi);
5310         if (err)
5311                 goto failed_mount3;
5312
5313         sbi->s_stripe = ext4_get_stripe_size(sbi);
5314         /*
5315          * It's hard to get stripe aligned blocks if stripe is not aligned with
5316          * cluster, just disable stripe and alert user to simpfy code and avoid
5317          * stripe aligned allocation which will rarely successes.
5318          */
5319         if (sbi->s_stripe > 0 && sbi->s_cluster_ratio > 1 &&
5320             sbi->s_stripe % sbi->s_cluster_ratio != 0) {
5321                 ext4_msg(sb, KERN_WARNING,
5322                          "stripe (%lu) is not aligned with cluster size (%u), "
5323                          "stripe is disabled",
5324                          sbi->s_stripe, sbi->s_cluster_ratio);
5325                 sbi->s_stripe = 0;
5326         }
5327         sbi->s_extent_max_zeroout_kb = 32;
5328
5329         /*
5330          * set up enough so that it can read an inode
5331          */
5332         sb->s_op = &ext4_sops;
5333         sb->s_export_op = &ext4_export_ops;
5334         sb->s_xattr = ext4_xattr_handlers;
5335 #ifdef CONFIG_FS_ENCRYPTION
5336         sb->s_cop = &ext4_cryptops;
5337 #endif
5338 #ifdef CONFIG_FS_VERITY
5339         sb->s_vop = &ext4_verityops;
5340 #endif
5341 #ifdef CONFIG_QUOTA
5342         sb->dq_op = &ext4_quota_operations;
5343         if (ext4_has_feature_quota(sb))
5344                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
5345         else
5346                 sb->s_qcop = &ext4_qctl_operations;
5347         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5348 #endif
5349         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
5350
5351         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5352         mutex_init(&sbi->s_orphan_lock);
5353
5354         ext4_fast_commit_init(sb);
5355
5356         sb->s_root = NULL;
5357
5358         needs_recovery = (es->s_last_orphan != 0 ||
5359                           ext4_has_feature_orphan_present(sb) ||
5360                           ext4_has_feature_journal_needs_recovery(sb));
5361
5362         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb)) {
5363                 err = ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block));
5364                 if (err)
5365                         goto failed_mount3a;
5366         }
5367
5368         err = -EINVAL;
5369         /*
5370          * The first inode we look at is the journal inode.  Don't try
5371          * root first: it may be modified in the journal!
5372          */
5373         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5374                 err = ext4_load_and_init_journal(sb, es, ctx);
5375                 if (err)
5376                         goto failed_mount3a;
5377         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5378                    ext4_has_feature_journal_needs_recovery(sb)) {
5379                 ext4_msg(sb, KERN_ERR, "required journal recovery "
5380                        "suppressed and not mounted read-only");
5381                 goto failed_mount3a;
5382         } else {
5383                 /* Nojournal mode, all journal mount options are illegal */
5384                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5385                         ext4_msg(sb, KERN_ERR, "can't mount with "
5386                                  "journal_async_commit, fs mounted w/o journal");
5387                         goto failed_mount3a;
5388                 }
5389
5390                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
5391                         ext4_msg(sb, KERN_ERR, "can't mount with "
5392                                  "journal_checksum, fs mounted w/o journal");
5393                         goto failed_mount3a;
5394                 }
5395                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
5396                         ext4_msg(sb, KERN_ERR, "can't mount with "
5397                                  "commit=%lu, fs mounted w/o journal",
5398                                  sbi->s_commit_interval / HZ);
5399                         goto failed_mount3a;
5400                 }
5401                 if (EXT4_MOUNT_DATA_FLAGS &
5402                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
5403                         ext4_msg(sb, KERN_ERR, "can't mount with "
5404                                  "data=, fs mounted w/o journal");
5405                         goto failed_mount3a;
5406                 }
5407                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5408                 clear_opt(sb, JOURNAL_CHECKSUM);
5409                 clear_opt(sb, DATA_FLAGS);
5410                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
5411                 sbi->s_journal = NULL;
5412                 needs_recovery = 0;
5413         }
5414
5415         if (!test_opt(sb, NO_MBCACHE)) {
5416                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
5417                 if (!sbi->s_ea_block_cache) {
5418                         ext4_msg(sb, KERN_ERR,
5419                                  "Failed to create ea_block_cache");
5420                         err = -EINVAL;
5421                         goto failed_mount_wq;
5422                 }
5423
5424                 if (ext4_has_feature_ea_inode(sb)) {
5425                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5426                         if (!sbi->s_ea_inode_cache) {
5427                                 ext4_msg(sb, KERN_ERR,
5428                                          "Failed to create ea_inode_cache");
5429                                 err = -EINVAL;
5430                                 goto failed_mount_wq;
5431                         }
5432                 }
5433         }
5434
5435         /*
5436          * Get the # of file system overhead blocks from the
5437          * superblock if present.
5438          */
5439         sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5440         /* ignore the precalculated value if it is ridiculous */
5441         if (sbi->s_overhead > ext4_blocks_count(es))
5442                 sbi->s_overhead = 0;
5443         /*
5444          * If the bigalloc feature is not enabled recalculating the
5445          * overhead doesn't take long, so we might as well just redo
5446          * it to make sure we are using the correct value.
5447          */
5448         if (!ext4_has_feature_bigalloc(sb))
5449                 sbi->s_overhead = 0;
5450         if (sbi->s_overhead == 0) {
5451                 err = ext4_calculate_overhead(sb);
5452                 if (err)
5453                         goto failed_mount_wq;
5454         }
5455
5456         /*
5457          * The maximum number of concurrent works can be high and
5458          * concurrency isn't really necessary.  Limit it to 1.
5459          */
5460         EXT4_SB(sb)->rsv_conversion_wq =
5461                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5462         if (!EXT4_SB(sb)->rsv_conversion_wq) {
5463                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5464                 err = -ENOMEM;
5465                 goto failed_mount4;
5466         }
5467
5468         /*
5469          * The jbd2_journal_load will have done any necessary log recovery,
5470          * so we can safely mount the rest of the filesystem now.
5471          */
5472
5473         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5474         if (IS_ERR(root)) {
5475                 ext4_msg(sb, KERN_ERR, "get root inode failed");
5476                 err = PTR_ERR(root);
5477                 root = NULL;
5478                 goto failed_mount4;
5479         }
5480         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5481                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5482                 iput(root);
5483                 err = -EFSCORRUPTED;
5484                 goto failed_mount4;
5485         }
5486
5487         sb->s_root = d_make_root(root);
5488         if (!sb->s_root) {
5489                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
5490                 err = -ENOMEM;
5491                 goto failed_mount4;
5492         }
5493
5494         err = ext4_setup_super(sb, es, sb_rdonly(sb));
5495         if (err == -EROFS) {
5496                 sb->s_flags |= SB_RDONLY;
5497         } else if (err)
5498                 goto failed_mount4a;
5499
5500         ext4_set_resv_clusters(sb);
5501
5502         if (test_opt(sb, BLOCK_VALIDITY)) {
5503                 err = ext4_setup_system_zone(sb);
5504                 if (err) {
5505                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
5506                                  "zone (%d)", err);
5507                         goto failed_mount4a;
5508                 }
5509         }
5510         ext4_fc_replay_cleanup(sb);
5511
5512         ext4_ext_init(sb);
5513
5514         /*
5515          * Enable optimize_scan if number of groups is > threshold. This can be
5516          * turned off by passing "mb_optimize_scan=0". This can also be
5517          * turned on forcefully by passing "mb_optimize_scan=1".
5518          */
5519         if (!(ctx->spec & EXT4_SPEC_mb_optimize_scan)) {
5520                 if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5521                         set_opt2(sb, MB_OPTIMIZE_SCAN);
5522                 else
5523                         clear_opt2(sb, MB_OPTIMIZE_SCAN);
5524         }
5525
5526         err = ext4_mb_init(sb);
5527         if (err) {
5528                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5529                          err);
5530                 goto failed_mount5;
5531         }
5532
5533         /*
5534          * We can only set up the journal commit callback once
5535          * mballoc is initialized
5536          */
5537         if (sbi->s_journal)
5538                 sbi->s_journal->j_commit_callback =
5539                         ext4_journal_commit_callback;
5540
5541         err = ext4_percpu_param_init(sbi);
5542         if (err)
5543                 goto failed_mount6;
5544
5545         if (ext4_has_feature_flex_bg(sb))
5546                 if (!ext4_fill_flex_info(sb)) {
5547                         ext4_msg(sb, KERN_ERR,
5548                                "unable to initialize "
5549                                "flex_bg meta info!");
5550                         err = -ENOMEM;
5551                         goto failed_mount6;
5552                 }
5553
5554         err = ext4_register_li_request(sb, first_not_zeroed);
5555         if (err)
5556                 goto failed_mount6;
5557
5558         err = ext4_register_sysfs(sb);
5559         if (err)
5560                 goto failed_mount7;
5561
5562         err = ext4_init_orphan_info(sb);
5563         if (err)
5564                 goto failed_mount8;
5565 #ifdef CONFIG_QUOTA
5566         /* Enable quota usage during mount. */
5567         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5568                 err = ext4_enable_quotas(sb);
5569                 if (err)
5570                         goto failed_mount9;
5571         }
5572 #endif  /* CONFIG_QUOTA */
5573
5574         /*
5575          * Save the original bdev mapping's wb_err value which could be
5576          * used to detect the metadata async write error.
5577          */
5578         spin_lock_init(&sbi->s_bdev_wb_lock);
5579         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5580                                  &sbi->s_bdev_wb_err);
5581         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5582         ext4_orphan_cleanup(sb, es);
5583         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5584         /*
5585          * Update the checksum after updating free space/inode counters and
5586          * ext4_orphan_cleanup. Otherwise the superblock can have an incorrect
5587          * checksum in the buffer cache until it is written out and
5588          * e2fsprogs programs trying to open a file system immediately
5589          * after it is mounted can fail.
5590          */
5591         ext4_superblock_csum_set(sb);
5592         if (needs_recovery) {
5593                 ext4_msg(sb, KERN_INFO, "recovery complete");
5594                 err = ext4_mark_recovery_complete(sb, es);
5595                 if (err)
5596                         goto failed_mount10;
5597         }
5598
5599         if (test_opt(sb, DISCARD) && !bdev_max_discard_sectors(sb->s_bdev))
5600                 ext4_msg(sb, KERN_WARNING,
5601                          "mounting with \"discard\" option, but the device does not support discard");
5602
5603         if (es->s_error_count)
5604                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5605
5606         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5607         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5608         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5609         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5610         atomic_set(&sbi->s_warning_count, 0);
5611         atomic_set(&sbi->s_msg_count, 0);
5612
5613         return 0;
5614
5615 failed_mount10:
5616         ext4_quotas_off(sb, EXT4_MAXQUOTAS);
5617 failed_mount9: __maybe_unused
5618         ext4_release_orphan_info(sb);
5619 failed_mount8:
5620         ext4_unregister_sysfs(sb);
5621         kobject_put(&sbi->s_kobj);
5622 failed_mount7:
5623         ext4_unregister_li_request(sb);
5624 failed_mount6:
5625         ext4_mb_release(sb);
5626         ext4_flex_groups_free(sbi);
5627         ext4_percpu_param_destroy(sbi);
5628 failed_mount5:
5629         ext4_ext_release(sb);
5630         ext4_release_system_zone(sb);
5631 failed_mount4a:
5632         dput(sb->s_root);
5633         sb->s_root = NULL;
5634 failed_mount4:
5635         ext4_msg(sb, KERN_ERR, "mount failed");
5636         if (EXT4_SB(sb)->rsv_conversion_wq)
5637                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5638 failed_mount_wq:
5639         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5640         sbi->s_ea_inode_cache = NULL;
5641
5642         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5643         sbi->s_ea_block_cache = NULL;
5644
5645         if (sbi->s_journal) {
5646                 /* flush s_sb_upd_work before journal destroy. */
5647                 flush_work(&sbi->s_sb_upd_work);
5648                 jbd2_journal_destroy(sbi->s_journal);
5649                 sbi->s_journal = NULL;
5650         }
5651 failed_mount3a:
5652         ext4_es_unregister_shrinker(sbi);
5653 failed_mount3:
5654         /* flush s_sb_upd_work before sbi destroy */
5655         flush_work(&sbi->s_sb_upd_work);
5656         del_timer_sync(&sbi->s_err_report);
5657         ext4_stop_mmpd(sbi);
5658         ext4_group_desc_free(sbi);
5659 failed_mount:
5660         if (sbi->s_chksum_driver)
5661                 crypto_free_shash(sbi->s_chksum_driver);
5662
5663 #if IS_ENABLED(CONFIG_UNICODE)
5664         utf8_unload(sb->s_encoding);
5665 #endif
5666
5667 #ifdef CONFIG_QUOTA
5668         for (unsigned int i = 0; i < EXT4_MAXQUOTAS; i++)
5669                 kfree(get_qf_name(sb, sbi, i));
5670 #endif
5671         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5672         brelse(sbi->s_sbh);
5673         if (sbi->s_journal_bdev_handle) {
5674                 invalidate_bdev(sbi->s_journal_bdev_handle->bdev);
5675                 bdev_release(sbi->s_journal_bdev_handle);
5676         }
5677 out_fail:
5678         invalidate_bdev(sb->s_bdev);
5679         sb->s_fs_info = NULL;
5680         return err;
5681 }
5682
5683 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5684 {
5685         struct ext4_fs_context *ctx = fc->fs_private;
5686         struct ext4_sb_info *sbi;
5687         const char *descr;
5688         int ret;
5689
5690         sbi = ext4_alloc_sbi(sb);
5691         if (!sbi)
5692                 return -ENOMEM;
5693
5694         fc->s_fs_info = sbi;
5695
5696         /* Cleanup superblock name */
5697         strreplace(sb->s_id, '/', '!');
5698
5699         sbi->s_sb_block = 1;    /* Default super block location */
5700         if (ctx->spec & EXT4_SPEC_s_sb_block)
5701                 sbi->s_sb_block = ctx->s_sb_block;
5702
5703         ret = __ext4_fill_super(fc, sb);
5704         if (ret < 0)
5705                 goto free_sbi;
5706
5707         if (sbi->s_journal) {
5708                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5709                         descr = " journalled data mode";
5710                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5711                         descr = " ordered data mode";
5712                 else
5713                         descr = " writeback data mode";
5714         } else
5715                 descr = "out journal";
5716
5717         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5718                 ext4_msg(sb, KERN_INFO, "mounted filesystem %pU %s with%s. "
5719                          "Quota mode: %s.", &sb->s_uuid,
5720                          sb_rdonly(sb) ? "ro" : "r/w", descr,
5721                          ext4_quota_mode(sb));
5722
5723         /* Update the s_overhead_clusters if necessary */
5724         ext4_update_overhead(sb, false);
5725         return 0;
5726
5727 free_sbi:
5728         ext4_free_sbi(sbi);
5729         fc->s_fs_info = NULL;
5730         return ret;
5731 }
5732
5733 static int ext4_get_tree(struct fs_context *fc)
5734 {
5735         return get_tree_bdev(fc, ext4_fill_super);
5736 }
5737
5738 /*
5739  * Setup any per-fs journal parameters now.  We'll do this both on
5740  * initial mount, once the journal has been initialised but before we've
5741  * done any recovery; and again on any subsequent remount.
5742  */
5743 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5744 {
5745         struct ext4_sb_info *sbi = EXT4_SB(sb);
5746
5747         journal->j_commit_interval = sbi->s_commit_interval;
5748         journal->j_min_batch_time = sbi->s_min_batch_time;
5749         journal->j_max_batch_time = sbi->s_max_batch_time;
5750         ext4_fc_init(sb, journal);
5751
5752         write_lock(&journal->j_state_lock);
5753         if (test_opt(sb, BARRIER))
5754                 journal->j_flags |= JBD2_BARRIER;
5755         else
5756                 journal->j_flags &= ~JBD2_BARRIER;
5757         if (test_opt(sb, DATA_ERR_ABORT))
5758                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5759         else
5760                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5761         /*
5762          * Always enable journal cycle record option, letting the journal
5763          * records log transactions continuously between each mount.
5764          */
5765         journal->j_flags |= JBD2_CYCLE_RECORD;
5766         write_unlock(&journal->j_state_lock);
5767 }
5768
5769 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5770                                              unsigned int journal_inum)
5771 {
5772         struct inode *journal_inode;
5773
5774         /*
5775          * Test for the existence of a valid inode on disk.  Bad things
5776          * happen if we iget() an unused inode, as the subsequent iput()
5777          * will try to delete it.
5778          */
5779         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5780         if (IS_ERR(journal_inode)) {
5781                 ext4_msg(sb, KERN_ERR, "no journal found");
5782                 return ERR_CAST(journal_inode);
5783         }
5784         if (!journal_inode->i_nlink) {
5785                 make_bad_inode(journal_inode);
5786                 iput(journal_inode);
5787                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5788                 return ERR_PTR(-EFSCORRUPTED);
5789         }
5790         if (!S_ISREG(journal_inode->i_mode) || IS_ENCRYPTED(journal_inode)) {
5791                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5792                 iput(journal_inode);
5793                 return ERR_PTR(-EFSCORRUPTED);
5794         }
5795
5796         ext4_debug("Journal inode found at %p: %lld bytes\n",
5797                   journal_inode, journal_inode->i_size);
5798         return journal_inode;
5799 }
5800
5801 static int ext4_journal_bmap(journal_t *journal, sector_t *block)
5802 {
5803         struct ext4_map_blocks map;
5804         int ret;
5805
5806         if (journal->j_inode == NULL)
5807                 return 0;
5808
5809         map.m_lblk = *block;
5810         map.m_len = 1;
5811         ret = ext4_map_blocks(NULL, journal->j_inode, &map, 0);
5812         if (ret <= 0) {
5813                 ext4_msg(journal->j_inode->i_sb, KERN_CRIT,
5814                          "journal bmap failed: block %llu ret %d\n",
5815                          *block, ret);
5816                 jbd2_journal_abort(journal, ret ? ret : -EIO);
5817                 return ret;
5818         }
5819         *block = map.m_pblk;
5820         return 0;
5821 }
5822
5823 static journal_t *ext4_open_inode_journal(struct super_block *sb,
5824                                           unsigned int journal_inum)
5825 {
5826         struct inode *journal_inode;
5827         journal_t *journal;
5828
5829         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5830         if (IS_ERR(journal_inode))
5831                 return ERR_CAST(journal_inode);
5832
5833         journal = jbd2_journal_init_inode(journal_inode);
5834         if (IS_ERR(journal)) {
5835                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5836                 iput(journal_inode);
5837                 return ERR_CAST(journal);
5838         }
5839         journal->j_private = sb;
5840         journal->j_bmap = ext4_journal_bmap;
5841         ext4_init_journal_params(sb, journal);
5842         return journal;
5843 }
5844
5845 static struct bdev_handle *ext4_get_journal_blkdev(struct super_block *sb,
5846                                         dev_t j_dev, ext4_fsblk_t *j_start,
5847                                         ext4_fsblk_t *j_len)
5848 {
5849         struct buffer_head *bh;
5850         struct block_device *bdev;
5851         struct bdev_handle *bdev_handle;
5852         int hblock, blocksize;
5853         ext4_fsblk_t sb_block;
5854         unsigned long offset;
5855         struct ext4_super_block *es;
5856         int errno;
5857
5858         bdev_handle = bdev_open_by_dev(j_dev,
5859                 BLK_OPEN_READ | BLK_OPEN_WRITE | BLK_OPEN_RESTRICT_WRITES,
5860                 sb, &fs_holder_ops);
5861         if (IS_ERR(bdev_handle)) {
5862                 ext4_msg(sb, KERN_ERR,
5863                          "failed to open journal device unknown-block(%u,%u) %ld",
5864                          MAJOR(j_dev), MINOR(j_dev), PTR_ERR(bdev_handle));
5865                 return bdev_handle;
5866         }
5867
5868         bdev = bdev_handle->bdev;
5869         blocksize = sb->s_blocksize;
5870         hblock = bdev_logical_block_size(bdev);
5871         if (blocksize < hblock) {
5872                 ext4_msg(sb, KERN_ERR,
5873                         "blocksize too small for journal device");
5874                 errno = -EINVAL;
5875                 goto out_bdev;
5876         }
5877
5878         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5879         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5880         set_blocksize(bdev, blocksize);
5881         bh = __bread(bdev, sb_block, blocksize);
5882         if (!bh) {
5883                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5884                        "external journal");
5885                 errno = -EINVAL;
5886                 goto out_bdev;
5887         }
5888
5889         es = (struct ext4_super_block *) (bh->b_data + offset);
5890         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5891             !(le32_to_cpu(es->s_feature_incompat) &
5892               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5893                 ext4_msg(sb, KERN_ERR, "external journal has bad superblock");
5894                 errno = -EFSCORRUPTED;
5895                 goto out_bh;
5896         }
5897
5898         if ((le32_to_cpu(es->s_feature_ro_compat) &
5899              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5900             es->s_checksum != ext4_superblock_csum(sb, es)) {
5901                 ext4_msg(sb, KERN_ERR, "external journal has corrupt superblock");
5902                 errno = -EFSCORRUPTED;
5903                 goto out_bh;
5904         }
5905
5906         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5907                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5908                 errno = -EFSCORRUPTED;
5909                 goto out_bh;
5910         }
5911
5912         *j_start = sb_block + 1;
5913         *j_len = ext4_blocks_count(es);
5914         brelse(bh);
5915         return bdev_handle;
5916
5917 out_bh:
5918         brelse(bh);
5919 out_bdev:
5920         bdev_release(bdev_handle);
5921         return ERR_PTR(errno);
5922 }
5923
5924 static journal_t *ext4_open_dev_journal(struct super_block *sb,
5925                                         dev_t j_dev)
5926 {
5927         journal_t *journal;
5928         ext4_fsblk_t j_start;
5929         ext4_fsblk_t j_len;
5930         struct bdev_handle *bdev_handle;
5931         int errno = 0;
5932
5933         bdev_handle = ext4_get_journal_blkdev(sb, j_dev, &j_start, &j_len);
5934         if (IS_ERR(bdev_handle))
5935                 return ERR_CAST(bdev_handle);
5936
5937         journal = jbd2_journal_init_dev(bdev_handle->bdev, sb->s_bdev, j_start,
5938                                         j_len, sb->s_blocksize);
5939         if (IS_ERR(journal)) {
5940                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5941                 errno = PTR_ERR(journal);
5942                 goto out_bdev;
5943         }
5944         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5945                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5946                                         "user (unsupported) - %d",
5947                         be32_to_cpu(journal->j_superblock->s_nr_users));
5948                 errno = -EINVAL;
5949                 goto out_journal;
5950         }
5951         journal->j_private = sb;
5952         EXT4_SB(sb)->s_journal_bdev_handle = bdev_handle;
5953         ext4_init_journal_params(sb, journal);
5954         return journal;
5955
5956 out_journal:
5957         jbd2_journal_destroy(journal);
5958 out_bdev:
5959         bdev_release(bdev_handle);
5960         return ERR_PTR(errno);
5961 }
5962
5963 static int ext4_load_journal(struct super_block *sb,
5964                              struct ext4_super_block *es,
5965                              unsigned long journal_devnum)
5966 {
5967         journal_t *journal;
5968         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5969         dev_t journal_dev;
5970         int err = 0;
5971         int really_read_only;
5972         int journal_dev_ro;
5973
5974         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5975                 return -EFSCORRUPTED;
5976
5977         if (journal_devnum &&
5978             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5979                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5980                         "numbers have changed");
5981                 journal_dev = new_decode_dev(journal_devnum);
5982         } else
5983                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5984
5985         if (journal_inum && journal_dev) {
5986                 ext4_msg(sb, KERN_ERR,
5987                          "filesystem has both journal inode and journal device!");
5988                 return -EINVAL;
5989         }
5990
5991         if (journal_inum) {
5992                 journal = ext4_open_inode_journal(sb, journal_inum);
5993                 if (IS_ERR(journal))
5994                         return PTR_ERR(journal);
5995         } else {
5996                 journal = ext4_open_dev_journal(sb, journal_dev);
5997                 if (IS_ERR(journal))
5998                         return PTR_ERR(journal);
5999         }
6000
6001         journal_dev_ro = bdev_read_only(journal->j_dev);
6002         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
6003
6004         if (journal_dev_ro && !sb_rdonly(sb)) {
6005                 ext4_msg(sb, KERN_ERR,
6006                          "journal device read-only, try mounting with '-o ro'");
6007                 err = -EROFS;
6008                 goto err_out;
6009         }
6010
6011         /*
6012          * Are we loading a blank journal or performing recovery after a
6013          * crash?  For recovery, we need to check in advance whether we
6014          * can get read-write access to the device.
6015          */
6016         if (ext4_has_feature_journal_needs_recovery(sb)) {
6017                 if (sb_rdonly(sb)) {
6018                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
6019                                         "required on readonly filesystem");
6020                         if (really_read_only) {
6021                                 ext4_msg(sb, KERN_ERR, "write access "
6022                                         "unavailable, cannot proceed "
6023                                         "(try mounting with noload)");
6024                                 err = -EROFS;
6025                                 goto err_out;
6026                         }
6027                         ext4_msg(sb, KERN_INFO, "write access will "
6028                                "be enabled during recovery");
6029                 }
6030         }
6031
6032         if (!(journal->j_flags & JBD2_BARRIER))
6033                 ext4_msg(sb, KERN_INFO, "barriers disabled");
6034
6035         if (!ext4_has_feature_journal_needs_recovery(sb))
6036                 err = jbd2_journal_wipe(journal, !really_read_only);
6037         if (!err) {
6038                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
6039                 __le16 orig_state;
6040                 bool changed = false;
6041
6042                 if (save)
6043                         memcpy(save, ((char *) es) +
6044                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
6045                 err = jbd2_journal_load(journal);
6046                 if (save && memcmp(((char *) es) + EXT4_S_ERR_START,
6047                                    save, EXT4_S_ERR_LEN)) {
6048                         memcpy(((char *) es) + EXT4_S_ERR_START,
6049                                save, EXT4_S_ERR_LEN);
6050                         changed = true;
6051                 }
6052                 kfree(save);
6053                 orig_state = es->s_state;
6054                 es->s_state |= cpu_to_le16(EXT4_SB(sb)->s_mount_state &
6055                                            EXT4_ERROR_FS);
6056                 if (orig_state != es->s_state)
6057                         changed = true;
6058                 /* Write out restored error information to the superblock */
6059                 if (changed && !really_read_only) {
6060                         int err2;
6061                         err2 = ext4_commit_super(sb);
6062                         err = err ? : err2;
6063                 }
6064         }
6065
6066         if (err) {
6067                 ext4_msg(sb, KERN_ERR, "error loading journal");
6068                 goto err_out;
6069         }
6070
6071         EXT4_SB(sb)->s_journal = journal;
6072         err = ext4_clear_journal_err(sb, es);
6073         if (err) {
6074                 EXT4_SB(sb)->s_journal = NULL;
6075                 jbd2_journal_destroy(journal);
6076                 return err;
6077         }
6078
6079         if (!really_read_only && journal_devnum &&
6080             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
6081                 es->s_journal_dev = cpu_to_le32(journal_devnum);
6082                 ext4_commit_super(sb);
6083         }
6084         if (!really_read_only && journal_inum &&
6085             journal_inum != le32_to_cpu(es->s_journal_inum)) {
6086                 es->s_journal_inum = cpu_to_le32(journal_inum);
6087                 ext4_commit_super(sb);
6088         }
6089
6090         return 0;
6091
6092 err_out:
6093         jbd2_journal_destroy(journal);
6094         return err;
6095 }
6096
6097 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
6098 static void ext4_update_super(struct super_block *sb)
6099 {
6100         struct ext4_sb_info *sbi = EXT4_SB(sb);
6101         struct ext4_super_block *es = sbi->s_es;
6102         struct buffer_head *sbh = sbi->s_sbh;
6103
6104         lock_buffer(sbh);
6105         /*
6106          * If the file system is mounted read-only, don't update the
6107          * superblock write time.  This avoids updating the superblock
6108          * write time when we are mounting the root file system
6109          * read/only but we need to replay the journal; at that point,
6110          * for people who are east of GMT and who make their clock
6111          * tick in localtime for Windows bug-for-bug compatibility,
6112          * the clock is set in the future, and this will cause e2fsck
6113          * to complain and force a full file system check.
6114          */
6115         if (!sb_rdonly(sb))
6116                 ext4_update_tstamp(es, s_wtime);
6117         es->s_kbytes_written =
6118                 cpu_to_le64(sbi->s_kbytes_written +
6119                     ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
6120                       sbi->s_sectors_written_start) >> 1));
6121         if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
6122                 ext4_free_blocks_count_set(es,
6123                         EXT4_C2B(sbi, percpu_counter_sum_positive(
6124                                 &sbi->s_freeclusters_counter)));
6125         if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
6126                 es->s_free_inodes_count =
6127                         cpu_to_le32(percpu_counter_sum_positive(
6128                                 &sbi->s_freeinodes_counter));
6129         /* Copy error information to the on-disk superblock */
6130         spin_lock(&sbi->s_error_lock);
6131         if (sbi->s_add_error_count > 0) {
6132                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6133                 if (!es->s_first_error_time && !es->s_first_error_time_hi) {
6134                         __ext4_update_tstamp(&es->s_first_error_time,
6135                                              &es->s_first_error_time_hi,
6136                                              sbi->s_first_error_time);
6137                         strncpy(es->s_first_error_func, sbi->s_first_error_func,
6138                                 sizeof(es->s_first_error_func));
6139                         es->s_first_error_line =
6140                                 cpu_to_le32(sbi->s_first_error_line);
6141                         es->s_first_error_ino =
6142                                 cpu_to_le32(sbi->s_first_error_ino);
6143                         es->s_first_error_block =
6144                                 cpu_to_le64(sbi->s_first_error_block);
6145                         es->s_first_error_errcode =
6146                                 ext4_errno_to_code(sbi->s_first_error_code);
6147                 }
6148                 __ext4_update_tstamp(&es->s_last_error_time,
6149                                      &es->s_last_error_time_hi,
6150                                      sbi->s_last_error_time);
6151                 strncpy(es->s_last_error_func, sbi->s_last_error_func,
6152                         sizeof(es->s_last_error_func));
6153                 es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
6154                 es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
6155                 es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
6156                 es->s_last_error_errcode =
6157                                 ext4_errno_to_code(sbi->s_last_error_code);
6158                 /*
6159                  * Start the daily error reporting function if it hasn't been
6160                  * started already
6161                  */
6162                 if (!es->s_error_count)
6163                         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
6164                 le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
6165                 sbi->s_add_error_count = 0;
6166         }
6167         spin_unlock(&sbi->s_error_lock);
6168
6169         ext4_superblock_csum_set(sb);
6170         unlock_buffer(sbh);
6171 }
6172
6173 static int ext4_commit_super(struct super_block *sb)
6174 {
6175         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
6176
6177         if (!sbh)
6178                 return -EINVAL;
6179         if (block_device_ejected(sb))
6180                 return -ENODEV;
6181
6182         ext4_update_super(sb);
6183
6184         lock_buffer(sbh);
6185         /* Buffer got discarded which means block device got invalidated */
6186         if (!buffer_mapped(sbh)) {
6187                 unlock_buffer(sbh);
6188                 return -EIO;
6189         }
6190
6191         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
6192                 /*
6193                  * Oh, dear.  A previous attempt to write the
6194                  * superblock failed.  This could happen because the
6195                  * USB device was yanked out.  Or it could happen to
6196                  * be a transient write error and maybe the block will
6197                  * be remapped.  Nothing we can do but to retry the
6198                  * write and hope for the best.
6199                  */
6200                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
6201                        "superblock detected");
6202                 clear_buffer_write_io_error(sbh);
6203                 set_buffer_uptodate(sbh);
6204         }
6205         get_bh(sbh);
6206         /* Clear potential dirty bit if it was journalled update */
6207         clear_buffer_dirty(sbh);
6208         sbh->b_end_io = end_buffer_write_sync;
6209         submit_bh(REQ_OP_WRITE | REQ_SYNC |
6210                   (test_opt(sb, BARRIER) ? REQ_FUA : 0), sbh);
6211         wait_on_buffer(sbh);
6212         if (buffer_write_io_error(sbh)) {
6213                 ext4_msg(sb, KERN_ERR, "I/O error while writing "
6214                        "superblock");
6215                 clear_buffer_write_io_error(sbh);
6216                 set_buffer_uptodate(sbh);
6217                 return -EIO;
6218         }
6219         return 0;
6220 }
6221
6222 /*
6223  * Have we just finished recovery?  If so, and if we are mounting (or
6224  * remounting) the filesystem readonly, then we will end up with a
6225  * consistent fs on disk.  Record that fact.
6226  */
6227 static int ext4_mark_recovery_complete(struct super_block *sb,
6228                                        struct ext4_super_block *es)
6229 {
6230         int err;
6231         journal_t *journal = EXT4_SB(sb)->s_journal;
6232
6233         if (!ext4_has_feature_journal(sb)) {
6234                 if (journal != NULL) {
6235                         ext4_error(sb, "Journal got removed while the fs was "
6236                                    "mounted!");
6237                         return -EFSCORRUPTED;
6238                 }
6239                 return 0;
6240         }
6241         jbd2_journal_lock_updates(journal);
6242         err = jbd2_journal_flush(journal, 0);
6243         if (err < 0)
6244                 goto out;
6245
6246         if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6247             ext4_has_feature_orphan_present(sb))) {
6248                 if (!ext4_orphan_file_empty(sb)) {
6249                         ext4_error(sb, "Orphan file not empty on read-only fs.");
6250                         err = -EFSCORRUPTED;
6251                         goto out;
6252                 }
6253                 ext4_clear_feature_journal_needs_recovery(sb);
6254                 ext4_clear_feature_orphan_present(sb);
6255                 ext4_commit_super(sb);
6256         }
6257 out:
6258         jbd2_journal_unlock_updates(journal);
6259         return err;
6260 }
6261
6262 /*
6263  * If we are mounting (or read-write remounting) a filesystem whose journal
6264  * has recorded an error from a previous lifetime, move that error to the
6265  * main filesystem now.
6266  */
6267 static int ext4_clear_journal_err(struct super_block *sb,
6268                                    struct ext4_super_block *es)
6269 {
6270         journal_t *journal;
6271         int j_errno;
6272         const char *errstr;
6273
6274         if (!ext4_has_feature_journal(sb)) {
6275                 ext4_error(sb, "Journal got removed while the fs was mounted!");
6276                 return -EFSCORRUPTED;
6277         }
6278
6279         journal = EXT4_SB(sb)->s_journal;
6280
6281         /*
6282          * Now check for any error status which may have been recorded in the
6283          * journal by a prior ext4_error() or ext4_abort()
6284          */
6285
6286         j_errno = jbd2_journal_errno(journal);
6287         if (j_errno) {
6288                 char nbuf[16];
6289
6290                 errstr = ext4_decode_error(sb, j_errno, nbuf);
6291                 ext4_warning(sb, "Filesystem error recorded "
6292                              "from previous mount: %s", errstr);
6293
6294                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6295                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6296                 j_errno = ext4_commit_super(sb);
6297                 if (j_errno)
6298                         return j_errno;
6299                 ext4_warning(sb, "Marked fs in need of filesystem check.");
6300
6301                 jbd2_journal_clear_err(journal);
6302                 jbd2_journal_update_sb_errno(journal);
6303         }
6304         return 0;
6305 }
6306
6307 /*
6308  * Force the running and committing transactions to commit,
6309  * and wait on the commit.
6310  */
6311 int ext4_force_commit(struct super_block *sb)
6312 {
6313         return ext4_journal_force_commit(EXT4_SB(sb)->s_journal);
6314 }
6315
6316 static int ext4_sync_fs(struct super_block *sb, int wait)
6317 {
6318         int ret = 0;
6319         tid_t target;
6320         bool needs_barrier = false;
6321         struct ext4_sb_info *sbi = EXT4_SB(sb);
6322
6323         if (unlikely(ext4_forced_shutdown(sb)))
6324                 return 0;
6325
6326         trace_ext4_sync_fs(sb, wait);
6327         flush_workqueue(sbi->rsv_conversion_wq);
6328         /*
6329          * Writeback quota in non-journalled quota case - journalled quota has
6330          * no dirty dquots
6331          */
6332         dquot_writeback_dquots(sb, -1);
6333         /*
6334          * Data writeback is possible w/o journal transaction, so barrier must
6335          * being sent at the end of the function. But we can skip it if
6336          * transaction_commit will do it for us.
6337          */
6338         if (sbi->s_journal) {
6339                 target = jbd2_get_latest_transaction(sbi->s_journal);
6340                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6341                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6342                         needs_barrier = true;
6343
6344                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6345                         if (wait)
6346                                 ret = jbd2_log_wait_commit(sbi->s_journal,
6347                                                            target);
6348                 }
6349         } else if (wait && test_opt(sb, BARRIER))
6350                 needs_barrier = true;
6351         if (needs_barrier) {
6352                 int err;
6353                 err = blkdev_issue_flush(sb->s_bdev);
6354                 if (!ret)
6355                         ret = err;
6356         }
6357
6358         return ret;
6359 }
6360
6361 /*
6362  * LVM calls this function before a (read-only) snapshot is created.  This
6363  * gives us a chance to flush the journal completely and mark the fs clean.
6364  *
6365  * Note that only this function cannot bring a filesystem to be in a clean
6366  * state independently. It relies on upper layer to stop all data & metadata
6367  * modifications.
6368  */
6369 static int ext4_freeze(struct super_block *sb)
6370 {
6371         int error = 0;
6372         journal_t *journal = EXT4_SB(sb)->s_journal;
6373
6374         if (journal) {
6375                 /* Now we set up the journal barrier. */
6376                 jbd2_journal_lock_updates(journal);
6377
6378                 /*
6379                  * Don't clear the needs_recovery flag if we failed to
6380                  * flush the journal.
6381                  */
6382                 error = jbd2_journal_flush(journal, 0);
6383                 if (error < 0)
6384                         goto out;
6385
6386                 /* Journal blocked and flushed, clear needs_recovery flag. */
6387                 ext4_clear_feature_journal_needs_recovery(sb);
6388                 if (ext4_orphan_file_empty(sb))
6389                         ext4_clear_feature_orphan_present(sb);
6390         }
6391
6392         error = ext4_commit_super(sb);
6393 out:
6394         if (journal)
6395                 /* we rely on upper layer to stop further updates */
6396                 jbd2_journal_unlock_updates(journal);
6397         return error;
6398 }
6399
6400 /*
6401  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6402  * flag here, even though the filesystem is not technically dirty yet.
6403  */
6404 static int ext4_unfreeze(struct super_block *sb)
6405 {
6406         if (ext4_forced_shutdown(sb))
6407                 return 0;
6408
6409         if (EXT4_SB(sb)->s_journal) {
6410                 /* Reset the needs_recovery flag before the fs is unlocked. */
6411                 ext4_set_feature_journal_needs_recovery(sb);
6412                 if (ext4_has_feature_orphan_file(sb))
6413                         ext4_set_feature_orphan_present(sb);
6414         }
6415
6416         ext4_commit_super(sb);
6417         return 0;
6418 }
6419
6420 /*
6421  * Structure to save mount options for ext4_remount's benefit
6422  */
6423 struct ext4_mount_options {
6424         unsigned long s_mount_opt;
6425         unsigned long s_mount_opt2;
6426         kuid_t s_resuid;
6427         kgid_t s_resgid;
6428         unsigned long s_commit_interval;
6429         u32 s_min_batch_time, s_max_batch_time;
6430 #ifdef CONFIG_QUOTA
6431         int s_jquota_fmt;
6432         char *s_qf_names[EXT4_MAXQUOTAS];
6433 #endif
6434 };
6435
6436 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6437 {
6438         struct ext4_fs_context *ctx = fc->fs_private;
6439         struct ext4_super_block *es;
6440         struct ext4_sb_info *sbi = EXT4_SB(sb);
6441         unsigned long old_sb_flags;
6442         struct ext4_mount_options old_opts;
6443         ext4_group_t g;
6444         int err = 0;
6445         int alloc_ctx;
6446 #ifdef CONFIG_QUOTA
6447         int enable_quota = 0;
6448         int i, j;
6449         char *to_free[EXT4_MAXQUOTAS];
6450 #endif
6451
6452
6453         /* Store the original options */
6454         old_sb_flags = sb->s_flags;
6455         old_opts.s_mount_opt = sbi->s_mount_opt;
6456         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6457         old_opts.s_resuid = sbi->s_resuid;
6458         old_opts.s_resgid = sbi->s_resgid;
6459         old_opts.s_commit_interval = sbi->s_commit_interval;
6460         old_opts.s_min_batch_time = sbi->s_min_batch_time;
6461         old_opts.s_max_batch_time = sbi->s_max_batch_time;
6462 #ifdef CONFIG_QUOTA
6463         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6464         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6465                 if (sbi->s_qf_names[i]) {
6466                         char *qf_name = get_qf_name(sb, sbi, i);
6467
6468                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6469                         if (!old_opts.s_qf_names[i]) {
6470                                 for (j = 0; j < i; j++)
6471                                         kfree(old_opts.s_qf_names[j]);
6472                                 return -ENOMEM;
6473                         }
6474                 } else
6475                         old_opts.s_qf_names[i] = NULL;
6476 #endif
6477         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)) {
6478                 if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6479                         ctx->journal_ioprio =
6480                                 sbi->s_journal->j_task->io_context->ioprio;
6481                 else
6482                         ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
6483
6484         }
6485
6486         /*
6487          * Changing the DIOREAD_NOLOCK or DELALLOC mount options may cause
6488          * two calls to ext4_should_dioread_nolock() to return inconsistent
6489          * values, triggering WARN_ON in ext4_add_complete_io(). we grab
6490          * here s_writepages_rwsem to avoid race between writepages ops and
6491          * remount.
6492          */
6493         alloc_ctx = ext4_writepages_down_write(sb);
6494         ext4_apply_options(fc, sb);
6495         ext4_writepages_up_write(sb, alloc_ctx);
6496
6497         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6498             test_opt(sb, JOURNAL_CHECKSUM)) {
6499                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6500                          "during remount not supported; ignoring");
6501                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6502         }
6503
6504         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6505                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6506                         ext4_msg(sb, KERN_ERR, "can't mount with "
6507                                  "both data=journal and delalloc");
6508                         err = -EINVAL;
6509                         goto restore_opts;
6510                 }
6511                 if (test_opt(sb, DIOREAD_NOLOCK)) {
6512                         ext4_msg(sb, KERN_ERR, "can't mount with "
6513                                  "both data=journal and dioread_nolock");
6514                         err = -EINVAL;
6515                         goto restore_opts;
6516                 }
6517         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6518                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6519                         ext4_msg(sb, KERN_ERR, "can't mount with "
6520                                 "journal_async_commit in data=ordered mode");
6521                         err = -EINVAL;
6522                         goto restore_opts;
6523                 }
6524         }
6525
6526         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6527                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6528                 err = -EINVAL;
6529                 goto restore_opts;
6530         }
6531
6532         if (test_opt2(sb, ABORT))
6533                 ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6534
6535         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6536                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6537
6538         es = sbi->s_es;
6539
6540         if (sbi->s_journal) {
6541                 ext4_init_journal_params(sb, sbi->s_journal);
6542                 set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6543         }
6544
6545         /* Flush outstanding errors before changing fs state */
6546         flush_work(&sbi->s_sb_upd_work);
6547
6548         if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6549                 if (ext4_forced_shutdown(sb)) {
6550                         err = -EROFS;
6551                         goto restore_opts;
6552                 }
6553
6554                 if (fc->sb_flags & SB_RDONLY) {
6555                         err = sync_filesystem(sb);
6556                         if (err < 0)
6557                                 goto restore_opts;
6558                         err = dquot_suspend(sb, -1);
6559                         if (err < 0)
6560                                 goto restore_opts;
6561
6562                         /*
6563                          * First of all, the unconditional stuff we have to do
6564                          * to disable replay of the journal when we next remount
6565                          */
6566                         sb->s_flags |= SB_RDONLY;
6567
6568                         /*
6569                          * OK, test if we are remounting a valid rw partition
6570                          * readonly, and if so set the rdonly flag and then
6571                          * mark the partition as valid again.
6572                          */
6573                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6574                             (sbi->s_mount_state & EXT4_VALID_FS))
6575                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
6576
6577                         if (sbi->s_journal) {
6578                                 /*
6579                                  * We let remount-ro finish even if marking fs
6580                                  * as clean failed...
6581                                  */
6582                                 ext4_mark_recovery_complete(sb, es);
6583                         }
6584                 } else {
6585                         /* Make sure we can mount this feature set readwrite */
6586                         if (ext4_has_feature_readonly(sb) ||
6587                             !ext4_feature_set_ok(sb, 0)) {
6588                                 err = -EROFS;
6589                                 goto restore_opts;
6590                         }
6591                         /*
6592                          * Make sure the group descriptor checksums
6593                          * are sane.  If they aren't, refuse to remount r/w.
6594                          */
6595                         for (g = 0; g < sbi->s_groups_count; g++) {
6596                                 struct ext4_group_desc *gdp =
6597                                         ext4_get_group_desc(sb, g, NULL);
6598
6599                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6600                                         ext4_msg(sb, KERN_ERR,
6601                "ext4_remount: Checksum for group %u failed (%u!=%u)",
6602                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6603                                                le16_to_cpu(gdp->bg_checksum));
6604                                         err = -EFSBADCRC;
6605                                         goto restore_opts;
6606                                 }
6607                         }
6608
6609                         /*
6610                          * If we have an unprocessed orphan list hanging
6611                          * around from a previously readonly bdev mount,
6612                          * require a full umount/remount for now.
6613                          */
6614                         if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6615                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
6616                                        "remount RDWR because of unprocessed "
6617                                        "orphan inode list.  Please "
6618                                        "umount/remount instead");
6619                                 err = -EINVAL;
6620                                 goto restore_opts;
6621                         }
6622
6623                         /*
6624                          * Mounting a RDONLY partition read-write, so reread
6625                          * and store the current valid flag.  (It may have
6626                          * been changed by e2fsck since we originally mounted
6627                          * the partition.)
6628                          */
6629                         if (sbi->s_journal) {
6630                                 err = ext4_clear_journal_err(sb, es);
6631                                 if (err)
6632                                         goto restore_opts;
6633                         }
6634                         sbi->s_mount_state = (le16_to_cpu(es->s_state) &
6635                                               ~EXT4_FC_REPLAY);
6636
6637                         err = ext4_setup_super(sb, es, 0);
6638                         if (err)
6639                                 goto restore_opts;
6640
6641                         sb->s_flags &= ~SB_RDONLY;
6642                         if (ext4_has_feature_mmp(sb)) {
6643                                 err = ext4_multi_mount_protect(sb,
6644                                                 le64_to_cpu(es->s_mmp_block));
6645                                 if (err)
6646                                         goto restore_opts;
6647                         }
6648 #ifdef CONFIG_QUOTA
6649                         enable_quota = 1;
6650 #endif
6651                 }
6652         }
6653
6654         /*
6655          * Handle creation of system zone data early because it can fail.
6656          * Releasing of existing data is done when we are sure remount will
6657          * succeed.
6658          */
6659         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6660                 err = ext4_setup_system_zone(sb);
6661                 if (err)
6662                         goto restore_opts;
6663         }
6664
6665         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6666                 err = ext4_commit_super(sb);
6667                 if (err)
6668                         goto restore_opts;
6669         }
6670
6671 #ifdef CONFIG_QUOTA
6672         if (enable_quota) {
6673                 if (sb_any_quota_suspended(sb))
6674                         dquot_resume(sb, -1);
6675                 else if (ext4_has_feature_quota(sb)) {
6676                         err = ext4_enable_quotas(sb);
6677                         if (err)
6678                                 goto restore_opts;
6679                 }
6680         }
6681         /* Release old quota file names */
6682         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6683                 kfree(old_opts.s_qf_names[i]);
6684 #endif
6685         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6686                 ext4_release_system_zone(sb);
6687
6688         /*
6689          * Reinitialize lazy itable initialization thread based on
6690          * current settings
6691          */
6692         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6693                 ext4_unregister_li_request(sb);
6694         else {
6695                 ext4_group_t first_not_zeroed;
6696                 first_not_zeroed = ext4_has_uninit_itable(sb);
6697                 ext4_register_li_request(sb, first_not_zeroed);
6698         }
6699
6700         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6701                 ext4_stop_mmpd(sbi);
6702
6703         return 0;
6704
6705 restore_opts:
6706         /*
6707          * If there was a failing r/w to ro transition, we may need to
6708          * re-enable quota
6709          */
6710         if (sb_rdonly(sb) && !(old_sb_flags & SB_RDONLY) &&
6711             sb_any_quota_suspended(sb))
6712                 dquot_resume(sb, -1);
6713
6714         alloc_ctx = ext4_writepages_down_write(sb);
6715         sb->s_flags = old_sb_flags;
6716         sbi->s_mount_opt = old_opts.s_mount_opt;
6717         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6718         sbi->s_resuid = old_opts.s_resuid;
6719         sbi->s_resgid = old_opts.s_resgid;
6720         sbi->s_commit_interval = old_opts.s_commit_interval;
6721         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6722         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6723         ext4_writepages_up_write(sb, alloc_ctx);
6724
6725         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6726                 ext4_release_system_zone(sb);
6727 #ifdef CONFIG_QUOTA
6728         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6729         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6730                 to_free[i] = get_qf_name(sb, sbi, i);
6731                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6732         }
6733         synchronize_rcu();
6734         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6735                 kfree(to_free[i]);
6736 #endif
6737         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6738                 ext4_stop_mmpd(sbi);
6739         return err;
6740 }
6741
6742 static int ext4_reconfigure(struct fs_context *fc)
6743 {
6744         struct super_block *sb = fc->root->d_sb;
6745         int ret;
6746
6747         fc->s_fs_info = EXT4_SB(sb);
6748
6749         ret = ext4_check_opt_consistency(fc, sb);
6750         if (ret < 0)
6751                 return ret;
6752
6753         ret = __ext4_remount(fc, sb);
6754         if (ret < 0)
6755                 return ret;
6756
6757         ext4_msg(sb, KERN_INFO, "re-mounted %pU %s. Quota mode: %s.",
6758                  &sb->s_uuid, sb_rdonly(sb) ? "ro" : "r/w",
6759                  ext4_quota_mode(sb));
6760
6761         return 0;
6762 }
6763
6764 #ifdef CONFIG_QUOTA
6765 static int ext4_statfs_project(struct super_block *sb,
6766                                kprojid_t projid, struct kstatfs *buf)
6767 {
6768         struct kqid qid;
6769         struct dquot *dquot;
6770         u64 limit;
6771         u64 curblock;
6772
6773         qid = make_kqid_projid(projid);
6774         dquot = dqget(sb, qid);
6775         if (IS_ERR(dquot))
6776                 return PTR_ERR(dquot);
6777         spin_lock(&dquot->dq_dqb_lock);
6778
6779         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6780                              dquot->dq_dqb.dqb_bhardlimit);
6781         limit >>= sb->s_blocksize_bits;
6782
6783         if (limit && buf->f_blocks > limit) {
6784                 curblock = (dquot->dq_dqb.dqb_curspace +
6785                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6786                 buf->f_blocks = limit;
6787                 buf->f_bfree = buf->f_bavail =
6788                         (buf->f_blocks > curblock) ?
6789                          (buf->f_blocks - curblock) : 0;
6790         }
6791
6792         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6793                              dquot->dq_dqb.dqb_ihardlimit);
6794         if (limit && buf->f_files > limit) {
6795                 buf->f_files = limit;
6796                 buf->f_ffree =
6797                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6798                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6799         }
6800
6801         spin_unlock(&dquot->dq_dqb_lock);
6802         dqput(dquot);
6803         return 0;
6804 }
6805 #endif
6806
6807 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6808 {
6809         struct super_block *sb = dentry->d_sb;
6810         struct ext4_sb_info *sbi = EXT4_SB(sb);
6811         struct ext4_super_block *es = sbi->s_es;
6812         ext4_fsblk_t overhead = 0, resv_blocks;
6813         s64 bfree;
6814         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6815
6816         if (!test_opt(sb, MINIX_DF))
6817                 overhead = sbi->s_overhead;
6818
6819         buf->f_type = EXT4_SUPER_MAGIC;
6820         buf->f_bsize = sb->s_blocksize;
6821         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6822         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6823                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6824         /* prevent underflow in case that few free space is available */
6825         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6826         buf->f_bavail = buf->f_bfree -
6827                         (ext4_r_blocks_count(es) + resv_blocks);
6828         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6829                 buf->f_bavail = 0;
6830         buf->f_files = le32_to_cpu(es->s_inodes_count);
6831         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6832         buf->f_namelen = EXT4_NAME_LEN;
6833         buf->f_fsid = uuid_to_fsid(es->s_uuid);
6834
6835 #ifdef CONFIG_QUOTA
6836         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6837             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6838                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6839 #endif
6840         return 0;
6841 }
6842
6843
6844 #ifdef CONFIG_QUOTA
6845
6846 /*
6847  * Helper functions so that transaction is started before we acquire dqio_sem
6848  * to keep correct lock ordering of transaction > dqio_sem
6849  */
6850 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6851 {
6852         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6853 }
6854
6855 static int ext4_write_dquot(struct dquot *dquot)
6856 {
6857         int ret, err;
6858         handle_t *handle;
6859         struct inode *inode;
6860
6861         inode = dquot_to_inode(dquot);
6862         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6863                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6864         if (IS_ERR(handle))
6865                 return PTR_ERR(handle);
6866         ret = dquot_commit(dquot);
6867         err = ext4_journal_stop(handle);
6868         if (!ret)
6869                 ret = err;
6870         return ret;
6871 }
6872
6873 static int ext4_acquire_dquot(struct dquot *dquot)
6874 {
6875         int ret, err;
6876         handle_t *handle;
6877
6878         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6879                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6880         if (IS_ERR(handle))
6881                 return PTR_ERR(handle);
6882         ret = dquot_acquire(dquot);
6883         err = ext4_journal_stop(handle);
6884         if (!ret)
6885                 ret = err;
6886         return ret;
6887 }
6888
6889 static int ext4_release_dquot(struct dquot *dquot)
6890 {
6891         int ret, err;
6892         handle_t *handle;
6893
6894         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6895                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6896         if (IS_ERR(handle)) {
6897                 /* Release dquot anyway to avoid endless cycle in dqput() */
6898                 dquot_release(dquot);
6899                 return PTR_ERR(handle);
6900         }
6901         ret = dquot_release(dquot);
6902         err = ext4_journal_stop(handle);
6903         if (!ret)
6904                 ret = err;
6905         return ret;
6906 }
6907
6908 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6909 {
6910         struct super_block *sb = dquot->dq_sb;
6911
6912         if (ext4_is_quota_journalled(sb)) {
6913                 dquot_mark_dquot_dirty(dquot);
6914                 return ext4_write_dquot(dquot);
6915         } else {
6916                 return dquot_mark_dquot_dirty(dquot);
6917         }
6918 }
6919
6920 static int ext4_write_info(struct super_block *sb, int type)
6921 {
6922         int ret, err;
6923         handle_t *handle;
6924
6925         /* Data block + inode block */
6926         handle = ext4_journal_start_sb(sb, EXT4_HT_QUOTA, 2);
6927         if (IS_ERR(handle))
6928                 return PTR_ERR(handle);
6929         ret = dquot_commit_info(sb, type);
6930         err = ext4_journal_stop(handle);
6931         if (!ret)
6932                 ret = err;
6933         return ret;
6934 }
6935
6936 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6937 {
6938         struct ext4_inode_info *ei = EXT4_I(inode);
6939
6940         /* The first argument of lockdep_set_subclass has to be
6941          * *exactly* the same as the argument to init_rwsem() --- in
6942          * this case, in init_once() --- or lockdep gets unhappy
6943          * because the name of the lock is set using the
6944          * stringification of the argument to init_rwsem().
6945          */
6946         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6947         lockdep_set_subclass(&ei->i_data_sem, subclass);
6948 }
6949
6950 /*
6951  * Standard function to be called on quota_on
6952  */
6953 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6954                          const struct path *path)
6955 {
6956         int err;
6957
6958         if (!test_opt(sb, QUOTA))
6959                 return -EINVAL;
6960
6961         /* Quotafile not on the same filesystem? */
6962         if (path->dentry->d_sb != sb)
6963                 return -EXDEV;
6964
6965         /* Quota already enabled for this file? */
6966         if (IS_NOQUOTA(d_inode(path->dentry)))
6967                 return -EBUSY;
6968
6969         /* Journaling quota? */
6970         if (EXT4_SB(sb)->s_qf_names[type]) {
6971                 /* Quotafile not in fs root? */
6972                 if (path->dentry->d_parent != sb->s_root)
6973                         ext4_msg(sb, KERN_WARNING,
6974                                 "Quota file not on filesystem root. "
6975                                 "Journaled quota will not work");
6976                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6977         } else {
6978                 /*
6979                  * Clear the flag just in case mount options changed since
6980                  * last time.
6981                  */
6982                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6983         }
6984
6985         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6986         err = dquot_quota_on(sb, type, format_id, path);
6987         if (!err) {
6988                 struct inode *inode = d_inode(path->dentry);
6989                 handle_t *handle;
6990
6991                 /*
6992                  * Set inode flags to prevent userspace from messing with quota
6993                  * files. If this fails, we return success anyway since quotas
6994                  * are already enabled and this is not a hard failure.
6995                  */
6996                 inode_lock(inode);
6997                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6998                 if (IS_ERR(handle))
6999                         goto unlock_inode;
7000                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
7001                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
7002                                 S_NOATIME | S_IMMUTABLE);
7003                 err = ext4_mark_inode_dirty(handle, inode);
7004                 ext4_journal_stop(handle);
7005         unlock_inode:
7006                 inode_unlock(inode);
7007                 if (err)
7008                         dquot_quota_off(sb, type);
7009         }
7010         if (err)
7011                 lockdep_set_quota_inode(path->dentry->d_inode,
7012                                              I_DATA_SEM_NORMAL);
7013         return err;
7014 }
7015
7016 static inline bool ext4_check_quota_inum(int type, unsigned long qf_inum)
7017 {
7018         switch (type) {
7019         case USRQUOTA:
7020                 return qf_inum == EXT4_USR_QUOTA_INO;
7021         case GRPQUOTA:
7022                 return qf_inum == EXT4_GRP_QUOTA_INO;
7023         case PRJQUOTA:
7024                 return qf_inum >= EXT4_GOOD_OLD_FIRST_INO;
7025         default:
7026                 BUG();
7027         }
7028 }
7029
7030 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
7031                              unsigned int flags)
7032 {
7033         int err;
7034         struct inode *qf_inode;
7035         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7036                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7037                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7038                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7039         };
7040
7041         BUG_ON(!ext4_has_feature_quota(sb));
7042
7043         if (!qf_inums[type])
7044                 return -EPERM;
7045
7046         if (!ext4_check_quota_inum(type, qf_inums[type])) {
7047                 ext4_error(sb, "Bad quota inum: %lu, type: %d",
7048                                 qf_inums[type], type);
7049                 return -EUCLEAN;
7050         }
7051
7052         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
7053         if (IS_ERR(qf_inode)) {
7054                 ext4_error(sb, "Bad quota inode: %lu, type: %d",
7055                                 qf_inums[type], type);
7056                 return PTR_ERR(qf_inode);
7057         }
7058
7059         /* Don't account quota for quota files to avoid recursion */
7060         qf_inode->i_flags |= S_NOQUOTA;
7061         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
7062         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
7063         if (err)
7064                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
7065         iput(qf_inode);
7066
7067         return err;
7068 }
7069
7070 /* Enable usage tracking for all quota types. */
7071 int ext4_enable_quotas(struct super_block *sb)
7072 {
7073         int type, err = 0;
7074         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7075                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7076                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7077                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7078         };
7079         bool quota_mopt[EXT4_MAXQUOTAS] = {
7080                 test_opt(sb, USRQUOTA),
7081                 test_opt(sb, GRPQUOTA),
7082                 test_opt(sb, PRJQUOTA),
7083         };
7084
7085         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
7086         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
7087                 if (qf_inums[type]) {
7088                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
7089                                 DQUOT_USAGE_ENABLED |
7090                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
7091                         if (err) {
7092                                 ext4_warning(sb,
7093                                         "Failed to enable quota tracking "
7094                                         "(type=%d, err=%d, ino=%lu). "
7095                                         "Please run e2fsck to fix.", type,
7096                                         err, qf_inums[type]);
7097
7098                                 ext4_quotas_off(sb, type);
7099                                 return err;
7100                         }
7101                 }
7102         }
7103         return 0;
7104 }
7105
7106 static int ext4_quota_off(struct super_block *sb, int type)
7107 {
7108         struct inode *inode = sb_dqopt(sb)->files[type];
7109         handle_t *handle;
7110         int err;
7111
7112         /* Force all delayed allocation blocks to be allocated.
7113          * Caller already holds s_umount sem */
7114         if (test_opt(sb, DELALLOC))
7115                 sync_filesystem(sb);
7116
7117         if (!inode || !igrab(inode))
7118                 goto out;
7119
7120         err = dquot_quota_off(sb, type);
7121         if (err || ext4_has_feature_quota(sb))
7122                 goto out_put;
7123         /*
7124          * When the filesystem was remounted read-only first, we cannot cleanup
7125          * inode flags here. Bad luck but people should be using QUOTA feature
7126          * these days anyway.
7127          */
7128         if (sb_rdonly(sb))
7129                 goto out_put;
7130
7131         inode_lock(inode);
7132         /*
7133          * Update modification times of quota files when userspace can
7134          * start looking at them. If we fail, we return success anyway since
7135          * this is not a hard failure and quotas are already disabled.
7136          */
7137         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7138         if (IS_ERR(handle)) {
7139                 err = PTR_ERR(handle);
7140                 goto out_unlock;
7141         }
7142         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
7143         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
7144         inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
7145         err = ext4_mark_inode_dirty(handle, inode);
7146         ext4_journal_stop(handle);
7147 out_unlock:
7148         inode_unlock(inode);
7149 out_put:
7150         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
7151         iput(inode);
7152         return err;
7153 out:
7154         return dquot_quota_off(sb, type);
7155 }
7156
7157 /* Read data from quotafile - avoid pagecache and such because we cannot afford
7158  * acquiring the locks... As quota files are never truncated and quota code
7159  * itself serializes the operations (and no one else should touch the files)
7160  * we don't have to be afraid of races */
7161 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
7162                                size_t len, loff_t off)
7163 {
7164         struct inode *inode = sb_dqopt(sb)->files[type];
7165         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7166         int offset = off & (sb->s_blocksize - 1);
7167         int tocopy;
7168         size_t toread;
7169         struct buffer_head *bh;
7170         loff_t i_size = i_size_read(inode);
7171
7172         if (off > i_size)
7173                 return 0;
7174         if (off+len > i_size)
7175                 len = i_size-off;
7176         toread = len;
7177         while (toread > 0) {
7178                 tocopy = min_t(unsigned long, sb->s_blocksize - offset, toread);
7179                 bh = ext4_bread(NULL, inode, blk, 0);
7180                 if (IS_ERR(bh))
7181                         return PTR_ERR(bh);
7182                 if (!bh)        /* A hole? */
7183                         memset(data, 0, tocopy);
7184                 else
7185                         memcpy(data, bh->b_data+offset, tocopy);
7186                 brelse(bh);
7187                 offset = 0;
7188                 toread -= tocopy;
7189                 data += tocopy;
7190                 blk++;
7191         }
7192         return len;
7193 }
7194
7195 /* Write to quotafile (we know the transaction is already started and has
7196  * enough credits) */
7197 static ssize_t ext4_quota_write(struct super_block *sb, int type,
7198                                 const char *data, size_t len, loff_t off)
7199 {
7200         struct inode *inode = sb_dqopt(sb)->files[type];
7201         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7202         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
7203         int retries = 0;
7204         struct buffer_head *bh;
7205         handle_t *handle = journal_current_handle();
7206
7207         if (!handle) {
7208                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7209                         " cancelled because transaction is not started",
7210                         (unsigned long long)off, (unsigned long long)len);
7211                 return -EIO;
7212         }
7213         /*
7214          * Since we account only one data block in transaction credits,
7215          * then it is impossible to cross a block boundary.
7216          */
7217         if (sb->s_blocksize - offset < len) {
7218                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7219                         " cancelled because not block aligned",
7220                         (unsigned long long)off, (unsigned long long)len);
7221                 return -EIO;
7222         }
7223
7224         do {
7225                 bh = ext4_bread(handle, inode, blk,
7226                                 EXT4_GET_BLOCKS_CREATE |
7227                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
7228         } while (PTR_ERR(bh) == -ENOSPC &&
7229                  ext4_should_retry_alloc(inode->i_sb, &retries));
7230         if (IS_ERR(bh))
7231                 return PTR_ERR(bh);
7232         if (!bh)
7233                 goto out;
7234         BUFFER_TRACE(bh, "get write access");
7235         err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
7236         if (err) {
7237                 brelse(bh);
7238                 return err;
7239         }
7240         lock_buffer(bh);
7241         memcpy(bh->b_data+offset, data, len);
7242         flush_dcache_page(bh->b_page);
7243         unlock_buffer(bh);
7244         err = ext4_handle_dirty_metadata(handle, NULL, bh);
7245         brelse(bh);
7246 out:
7247         if (inode->i_size < off + len) {
7248                 i_size_write(inode, off + len);
7249                 EXT4_I(inode)->i_disksize = inode->i_size;
7250                 err2 = ext4_mark_inode_dirty(handle, inode);
7251                 if (unlikely(err2 && !err))
7252                         err = err2;
7253         }
7254         return err ? err : len;
7255 }
7256 #endif
7257
7258 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
7259 static inline void register_as_ext2(void)
7260 {
7261         int err = register_filesystem(&ext2_fs_type);
7262         if (err)
7263                 printk(KERN_WARNING
7264                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7265 }
7266
7267 static inline void unregister_as_ext2(void)
7268 {
7269         unregister_filesystem(&ext2_fs_type);
7270 }
7271
7272 static inline int ext2_feature_set_ok(struct super_block *sb)
7273 {
7274         if (ext4_has_unknown_ext2_incompat_features(sb))
7275                 return 0;
7276         if (sb_rdonly(sb))
7277                 return 1;
7278         if (ext4_has_unknown_ext2_ro_compat_features(sb))
7279                 return 0;
7280         return 1;
7281 }
7282 #else
7283 static inline void register_as_ext2(void) { }
7284 static inline void unregister_as_ext2(void) { }
7285 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7286 #endif
7287
7288 static inline void register_as_ext3(void)
7289 {
7290         int err = register_filesystem(&ext3_fs_type);
7291         if (err)
7292                 printk(KERN_WARNING
7293                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7294 }
7295
7296 static inline void unregister_as_ext3(void)
7297 {
7298         unregister_filesystem(&ext3_fs_type);
7299 }
7300
7301 static inline int ext3_feature_set_ok(struct super_block *sb)
7302 {
7303         if (ext4_has_unknown_ext3_incompat_features(sb))
7304                 return 0;
7305         if (!ext4_has_feature_journal(sb))
7306                 return 0;
7307         if (sb_rdonly(sb))
7308                 return 1;
7309         if (ext4_has_unknown_ext3_ro_compat_features(sb))
7310                 return 0;
7311         return 1;
7312 }
7313
7314 static void ext4_kill_sb(struct super_block *sb)
7315 {
7316         struct ext4_sb_info *sbi = EXT4_SB(sb);
7317         struct bdev_handle *handle = sbi ? sbi->s_journal_bdev_handle : NULL;
7318
7319         kill_block_super(sb);
7320
7321         if (handle)
7322                 bdev_release(handle);
7323 }
7324
7325 static struct file_system_type ext4_fs_type = {
7326         .owner                  = THIS_MODULE,
7327         .name                   = "ext4",
7328         .init_fs_context        = ext4_init_fs_context,
7329         .parameters             = ext4_param_specs,
7330         .kill_sb                = ext4_kill_sb,
7331         .fs_flags               = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
7332 };
7333 MODULE_ALIAS_FS("ext4");
7334
7335 /* Shared across all ext4 file systems */
7336 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
7337
7338 static int __init ext4_init_fs(void)
7339 {
7340         int i, err;
7341
7342         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7343         ext4_li_info = NULL;
7344
7345         /* Build-time check for flags consistency */
7346         ext4_check_flag_values();
7347
7348         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
7349                 init_waitqueue_head(&ext4__ioend_wq[i]);
7350
7351         err = ext4_init_es();
7352         if (err)
7353                 return err;
7354
7355         err = ext4_init_pending();
7356         if (err)
7357                 goto out7;
7358
7359         err = ext4_init_post_read_processing();
7360         if (err)
7361                 goto out6;
7362
7363         err = ext4_init_pageio();
7364         if (err)
7365                 goto out5;
7366
7367         err = ext4_init_system_zone();
7368         if (err)
7369                 goto out4;
7370
7371         err = ext4_init_sysfs();
7372         if (err)
7373                 goto out3;
7374
7375         err = ext4_init_mballoc();
7376         if (err)
7377                 goto out2;
7378         err = init_inodecache();
7379         if (err)
7380                 goto out1;
7381
7382         err = ext4_fc_init_dentry_cache();
7383         if (err)
7384                 goto out05;
7385
7386         register_as_ext3();
7387         register_as_ext2();
7388         err = register_filesystem(&ext4_fs_type);
7389         if (err)
7390                 goto out;
7391
7392         return 0;
7393 out:
7394         unregister_as_ext2();
7395         unregister_as_ext3();
7396         ext4_fc_destroy_dentry_cache();
7397 out05:
7398         destroy_inodecache();
7399 out1:
7400         ext4_exit_mballoc();
7401 out2:
7402         ext4_exit_sysfs();
7403 out3:
7404         ext4_exit_system_zone();
7405 out4:
7406         ext4_exit_pageio();
7407 out5:
7408         ext4_exit_post_read_processing();
7409 out6:
7410         ext4_exit_pending();
7411 out7:
7412         ext4_exit_es();
7413
7414         return err;
7415 }
7416
7417 static void __exit ext4_exit_fs(void)
7418 {
7419         ext4_destroy_lazyinit_thread();
7420         unregister_as_ext2();
7421         unregister_as_ext3();
7422         unregister_filesystem(&ext4_fs_type);
7423         ext4_fc_destroy_dentry_cache();
7424         destroy_inodecache();
7425         ext4_exit_mballoc();
7426         ext4_exit_sysfs();
7427         ext4_exit_system_zone();
7428         ext4_exit_pageio();
7429         ext4_exit_post_read_processing();
7430         ext4_exit_es();
7431         ext4_exit_pending();
7432 }
7433
7434 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7435 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7436 MODULE_LICENSE("GPL");
7437 MODULE_SOFTDEP("pre: crc32c");
7438 module_init(ext4_init_fs)
7439 module_exit(ext4_exit_fs)