fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card ([email protected])
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller ([email protected]), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/uaccess.h>
  43 #include <linux/iversion.h>
  44 #include <linux/unicode.h>
  45 #include <linux/part_stat.h>
  46 #include <linux/kthread.h>
  47 #include <linux/freezer.h>
  48 #include <linux/fsnotify.h>
  49 #include <linux/fs_context.h>
  50 #include <linux/fs_parser.h>
  51
  52 #include "ext4.h"
  53 #include "ext4_extents.h"       /* Needed for trace points definition */
  54 #include "ext4_jbd2.h"
  55 #include "xattr.h"
  56 #include "acl.h"
  57 #include "mballoc.h"
  58 #include "fsmap.h"
  59
  60 #define CREATE_TRACE_POINTS
  61 #include <trace/events/ext4.h>
  62
  63 static struct ext4_lazy_init *ext4_li_info;
  64 static DEFINE_MUTEX(ext4_li_mtx);
  65 static struct ratelimit_state ext4_mount_msg_ratelimit;
  66
  67 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  68                              unsigned long journal_devnum);
  69 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  70 static void ext4_update_super(struct super_block *sb);
  71 static int ext4_commit_super(struct super_block *sb);
  72 static int ext4_mark_recovery_complete(struct super_block *sb,
  73                                         struct ext4_super_block *es);
  74 static int ext4_clear_journal_err(struct super_block *sb,
  75                                   struct ext4_super_block *es);
  76 static int ext4_sync_fs(struct super_block *sb, int wait);
  77 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  78 static int ext4_unfreeze(struct super_block *sb);
  79 static int ext4_freeze(struct super_block *sb);
  80 static inline int ext2_feature_set_ok(struct super_block *sb);
  81 static inline int ext3_feature_set_ok(struct super_block *sb);
  82 static void ext4_destroy_lazyinit_thread(void);
  83 static void ext4_unregister_li_request(struct super_block *sb);
  84 static void ext4_clear_request_list(void);
  85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  86                                             unsigned int journal_inum);
  87 static int ext4_validate_options(struct fs_context *fc);
  88 static int ext4_check_opt_consistency(struct fs_context *fc,
  89                                       struct super_block *sb);
  90 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb);
  91 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param);
  92 static int ext4_get_tree(struct fs_context *fc);
  93 static int ext4_reconfigure(struct fs_context *fc);
  94 static void ext4_fc_free(struct fs_context *fc);
  95 static int ext4_init_fs_context(struct fs_context *fc);
  96 static void ext4_kill_sb(struct super_block *sb);
  97 static const struct fs_parameter_spec ext4_param_specs[];
  98
  99 /*
 100  * Lock ordering
 101  *
 102  * page fault path:
 103  * mmap_lock -> sb_start_pagefault -> invalidate_lock (r) -> transaction start
 104  *   -> page lock -> i_data_sem (rw)
 105  *
 106  * buffered write path:
 107  * sb_start_write -> i_mutex -> mmap_lock
 108  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 109  *   i_data_sem (rw)
 110  *
 111  * truncate:
 112  * sb_start_write -> i_mutex -> invalidate_lock (w) -> i_mmap_rwsem (w) ->
 113  *   page lock
 114  * sb_start_write -> i_mutex -> invalidate_lock (w) -> transaction start ->
 115  *   i_data_sem (rw)
 116  *
 117  * direct IO:
 118  * sb_start_write -> i_mutex -> mmap_lock
 119  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 120  *
 121  * writepages:
 122  * transaction start -> page lock(s) -> i_data_sem (rw)
 123  */
 124
 125 static const struct fs_context_operations ext4_context_ops = {
 126         .parse_param    = ext4_parse_param,
 127         .get_tree       = ext4_get_tree,
 128         .reconfigure    = ext4_reconfigure,
 129         .free           = ext4_fc_free,
 130 };
 131
 132
 133 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 134 static struct file_system_type ext2_fs_type = {
 135         .owner                  = THIS_MODULE,
 136         .name                   = "ext2",
 137         .init_fs_context        = ext4_init_fs_context,
 138         .parameters             = ext4_param_specs,
 139         .kill_sb                = ext4_kill_sb,
 140         .fs_flags               = FS_REQUIRES_DEV,
 141 };
 142 MODULE_ALIAS_FS("ext2");
 143 MODULE_ALIAS("ext2");
 144 #define IS_EXT2_SB(sb) ((sb)->s_type == &ext2_fs_type)
 145 #else
 146 #define IS_EXT2_SB(sb) (0)
 147 #endif
 148
 149
 150 static struct file_system_type ext3_fs_type = {
 151         .owner                  = THIS_MODULE,
 152         .name                   = "ext3",
 153         .init_fs_context        = ext4_init_fs_context,
 154         .parameters             = ext4_param_specs,
 155         .kill_sb                = ext4_kill_sb,
 156         .fs_flags               = FS_REQUIRES_DEV,
 157 };
 158 MODULE_ALIAS_FS("ext3");
 159 MODULE_ALIAS("ext3");
 160 #define IS_EXT3_SB(sb) ((sb)->s_type == &ext3_fs_type)
 161
 162
 163 static inline void __ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
 164                                   bh_end_io_t *end_io)
 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_file) {
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(file_bdev(sbi->s_journal_bdev_file));
1369                 invalidate_bdev(file_bdev(sbi->s_journal_bdev_file));
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_ACCOUNT,
1504                                 offsetof(struct ext4_inode_info, i_data),
1505                                 sizeof_field(struct ext4_inode_info, i_data),
1506                                 init_once);
1507         if (ext4_inode_cachep == NULL)
1508                 return -ENOMEM;
1509         return 0;
1510 }
1511
1512 static void destroy_inodecache(void)
1513 {
1514         /*
1515          * Make sure all delayed rcu free inodes are flushed before we
1516          * destroy cache.
1517          */
1518         rcu_barrier();
1519         kmem_cache_destroy(ext4_inode_cachep);
1520 }
1521
1522 void ext4_clear_inode(struct inode *inode)
1523 {
1524         ext4_fc_del(inode);
1525         invalidate_inode_buffers(inode);
1526         clear_inode(inode);
1527         ext4_discard_preallocations(inode);
1528         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1529         dquot_drop(inode);
1530         if (EXT4_I(inode)->jinode) {
1531                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1532                                                EXT4_I(inode)->jinode);
1533                 jbd2_free_inode(EXT4_I(inode)->jinode);
1534                 EXT4_I(inode)->jinode = NULL;
1535         }
1536         fscrypt_put_encryption_info(inode);
1537         fsverity_cleanup_inode(inode);
1538 }
1539
1540 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1541                                         u64 ino, u32 generation)
1542 {
1543         struct inode *inode;
1544
1545         /*
1546          * Currently we don't know the generation for parent directory, so
1547          * a generation of 0 means "accept any"
1548          */
1549         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1550         if (IS_ERR(inode))
1551                 return ERR_CAST(inode);
1552         if (generation && inode->i_generation != generation) {
1553                 iput(inode);
1554                 return ERR_PTR(-ESTALE);
1555         }
1556
1557         return inode;
1558 }
1559
1560 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1561                                         int fh_len, int fh_type)
1562 {
1563         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1564                                     ext4_nfs_get_inode);
1565 }
1566
1567 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1568                                         int fh_len, int fh_type)
1569 {
1570         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1571                                     ext4_nfs_get_inode);
1572 }
1573
1574 static int ext4_nfs_commit_metadata(struct inode *inode)
1575 {
1576         struct writeback_control wbc = {
1577                 .sync_mode = WB_SYNC_ALL
1578         };
1579
1580         trace_ext4_nfs_commit_metadata(inode);
1581         return ext4_write_inode(inode, &wbc);
1582 }
1583
1584 #ifdef CONFIG_QUOTA
1585 static const char * const quotatypes[] = INITQFNAMES;
1586 #define QTYPE2NAME(t) (quotatypes[t])
1587
1588 static int ext4_write_dquot(struct dquot *dquot);
1589 static int ext4_acquire_dquot(struct dquot *dquot);
1590 static int ext4_release_dquot(struct dquot *dquot);
1591 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1592 static int ext4_write_info(struct super_block *sb, int type);
1593 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1594                          const struct path *path);
1595 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1596                                size_t len, loff_t off);
1597 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1598                                 const char *data, size_t len, loff_t off);
1599 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1600                              unsigned int flags);
1601
1602 static struct dquot __rcu **ext4_get_dquots(struct inode *inode)
1603 {
1604         return EXT4_I(inode)->i_dquot;
1605 }
1606
1607 static const struct dquot_operations ext4_quota_operations = {
1608         .get_reserved_space     = ext4_get_reserved_space,
1609         .write_dquot            = ext4_write_dquot,
1610         .acquire_dquot          = ext4_acquire_dquot,
1611         .release_dquot          = ext4_release_dquot,
1612         .mark_dirty             = ext4_mark_dquot_dirty,
1613         .write_info             = ext4_write_info,
1614         .alloc_dquot            = dquot_alloc,
1615         .destroy_dquot          = dquot_destroy,
1616         .get_projid             = ext4_get_projid,
1617         .get_inode_usage        = ext4_get_inode_usage,
1618         .get_next_id            = dquot_get_next_id,
1619 };
1620
1621 static const struct quotactl_ops ext4_qctl_operations = {
1622         .quota_on       = ext4_quota_on,
1623         .quota_off      = ext4_quota_off,
1624         .quota_sync     = dquot_quota_sync,
1625         .get_state      = dquot_get_state,
1626         .set_info       = dquot_set_dqinfo,
1627         .get_dqblk      = dquot_get_dqblk,
1628         .set_dqblk      = dquot_set_dqblk,
1629         .get_nextdqblk  = dquot_get_next_dqblk,
1630 };
1631 #endif
1632
1633 static const struct super_operations ext4_sops = {
1634         .alloc_inode    = ext4_alloc_inode,
1635         .free_inode     = ext4_free_in_core_inode,
1636         .destroy_inode  = ext4_destroy_inode,
1637         .write_inode    = ext4_write_inode,
1638         .dirty_inode    = ext4_dirty_inode,
1639         .drop_inode     = ext4_drop_inode,
1640         .evict_inode    = ext4_evict_inode,
1641         .put_super      = ext4_put_super,
1642         .sync_fs        = ext4_sync_fs,
1643         .freeze_fs      = ext4_freeze,
1644         .unfreeze_fs    = ext4_unfreeze,
1645         .statfs         = ext4_statfs,
1646         .show_options   = ext4_show_options,
1647         .shutdown       = ext4_shutdown,
1648 #ifdef CONFIG_QUOTA
1649         .quota_read     = ext4_quota_read,
1650         .quota_write    = ext4_quota_write,
1651         .get_dquots     = ext4_get_dquots,
1652 #endif
1653 };
1654
1655 static const struct export_operations ext4_export_ops = {
1656         .encode_fh = generic_encode_ino32_fh,
1657         .fh_to_dentry = ext4_fh_to_dentry,
1658         .fh_to_parent = ext4_fh_to_parent,
1659         .get_parent = ext4_get_parent,
1660         .commit_metadata = ext4_nfs_commit_metadata,
1661 };
1662
1663 enum {
1664         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1665         Opt_resgid, Opt_resuid, Opt_sb,
1666         Opt_nouid32, Opt_debug, Opt_removed,
1667         Opt_user_xattr, Opt_acl,
1668         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1669         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1670         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1671         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1672         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1673         Opt_inlinecrypt,
1674         Opt_usrjquota, Opt_grpjquota, Opt_quota,
1675         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1676         Opt_usrquota, Opt_grpquota, Opt_prjquota,
1677         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1678         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1679         Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
1680         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1681         Opt_inode_readahead_blks, Opt_journal_ioprio,
1682         Opt_dioread_nolock, Opt_dioread_lock,
1683         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1684         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1685         Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1686         Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
1687 #ifdef CONFIG_EXT4_DEBUG
1688         Opt_fc_debug_max_replay, Opt_fc_debug_force
1689 #endif
1690 };
1691
1692 static const struct constant_table ext4_param_errors[] = {
1693         {"continue",    EXT4_MOUNT_ERRORS_CONT},
1694         {"panic",       EXT4_MOUNT_ERRORS_PANIC},
1695         {"remount-ro",  EXT4_MOUNT_ERRORS_RO},
1696         {}
1697 };
1698
1699 static const struct constant_table ext4_param_data[] = {
1700         {"journal",     EXT4_MOUNT_JOURNAL_DATA},
1701         {"ordered",     EXT4_MOUNT_ORDERED_DATA},
1702         {"writeback",   EXT4_MOUNT_WRITEBACK_DATA},
1703         {}
1704 };
1705
1706 static const struct constant_table ext4_param_data_err[] = {
1707         {"abort",       Opt_data_err_abort},
1708         {"ignore",      Opt_data_err_ignore},
1709         {}
1710 };
1711
1712 static const struct constant_table ext4_param_jqfmt[] = {
1713         {"vfsold",      QFMT_VFS_OLD},
1714         {"vfsv0",       QFMT_VFS_V0},
1715         {"vfsv1",       QFMT_VFS_V1},
1716         {}
1717 };
1718
1719 static const struct constant_table ext4_param_dax[] = {
1720         {"always",      Opt_dax_always},
1721         {"inode",       Opt_dax_inode},
1722         {"never",       Opt_dax_never},
1723         {}
1724 };
1725
1726 /* String parameter that allows empty argument */
1727 #define fsparam_string_empty(NAME, OPT) \
1728         __fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
1729
1730 /*
1731  * Mount option specification
1732  * We don't use fsparam_flag_no because of the way we set the
1733  * options and the way we show them in _ext4_show_options(). To
1734  * keep the changes to a minimum, let's keep the negative options
1735  * separate for now.
1736  */
1737 static const struct fs_parameter_spec ext4_param_specs[] = {
1738         fsparam_flag    ("bsddf",               Opt_bsd_df),
1739         fsparam_flag    ("minixdf",             Opt_minix_df),
1740         fsparam_flag    ("grpid",               Opt_grpid),
1741         fsparam_flag    ("bsdgroups",           Opt_grpid),
1742         fsparam_flag    ("nogrpid",             Opt_nogrpid),
1743         fsparam_flag    ("sysvgroups",          Opt_nogrpid),
1744         fsparam_u32     ("resgid",              Opt_resgid),
1745         fsparam_u32     ("resuid",              Opt_resuid),
1746         fsparam_u32     ("sb",                  Opt_sb),
1747         fsparam_enum    ("errors",              Opt_errors, ext4_param_errors),
1748         fsparam_flag    ("nouid32",             Opt_nouid32),
1749         fsparam_flag    ("debug",               Opt_debug),
1750         fsparam_flag    ("oldalloc",            Opt_removed),
1751         fsparam_flag    ("orlov",               Opt_removed),
1752         fsparam_flag    ("user_xattr",          Opt_user_xattr),
1753         fsparam_flag    ("acl",                 Opt_acl),
1754         fsparam_flag    ("norecovery",          Opt_noload),
1755         fsparam_flag    ("noload",              Opt_noload),
1756         fsparam_flag    ("bh",                  Opt_removed),
1757         fsparam_flag    ("nobh",                Opt_removed),
1758         fsparam_u32     ("commit",              Opt_commit),
1759         fsparam_u32     ("min_batch_time",      Opt_min_batch_time),
1760         fsparam_u32     ("max_batch_time",      Opt_max_batch_time),
1761         fsparam_u32     ("journal_dev",         Opt_journal_dev),
1762         fsparam_bdev    ("journal_path",        Opt_journal_path),
1763         fsparam_flag    ("journal_checksum",    Opt_journal_checksum),
1764         fsparam_flag    ("nojournal_checksum",  Opt_nojournal_checksum),
1765         fsparam_flag    ("journal_async_commit",Opt_journal_async_commit),
1766         fsparam_flag    ("abort",               Opt_abort),
1767         fsparam_enum    ("data",                Opt_data, ext4_param_data),
1768         fsparam_enum    ("data_err",            Opt_data_err,
1769                                                 ext4_param_data_err),
1770         fsparam_string_empty
1771                         ("usrjquota",           Opt_usrjquota),
1772         fsparam_string_empty
1773                         ("grpjquota",           Opt_grpjquota),
1774         fsparam_enum    ("jqfmt",               Opt_jqfmt, ext4_param_jqfmt),
1775         fsparam_flag    ("grpquota",            Opt_grpquota),
1776         fsparam_flag    ("quota",               Opt_quota),
1777         fsparam_flag    ("noquota",             Opt_noquota),
1778         fsparam_flag    ("usrquota",            Opt_usrquota),
1779         fsparam_flag    ("prjquota",            Opt_prjquota),
1780         fsparam_flag    ("barrier",             Opt_barrier),
1781         fsparam_u32     ("barrier",             Opt_barrier),
1782         fsparam_flag    ("nobarrier",           Opt_nobarrier),
1783         fsparam_flag    ("i_version",           Opt_removed),
1784         fsparam_flag    ("dax",                 Opt_dax),
1785         fsparam_enum    ("dax",                 Opt_dax_type, ext4_param_dax),
1786         fsparam_u32     ("stripe",              Opt_stripe),
1787         fsparam_flag    ("delalloc",            Opt_delalloc),
1788         fsparam_flag    ("nodelalloc",          Opt_nodelalloc),
1789         fsparam_flag    ("warn_on_error",       Opt_warn_on_error),
1790         fsparam_flag    ("nowarn_on_error",     Opt_nowarn_on_error),
1791         fsparam_u32     ("debug_want_extra_isize",
1792                                                 Opt_debug_want_extra_isize),
1793         fsparam_flag    ("mblk_io_submit",      Opt_removed),
1794         fsparam_flag    ("nomblk_io_submit",    Opt_removed),
1795         fsparam_flag    ("block_validity",      Opt_block_validity),
1796         fsparam_flag    ("noblock_validity",    Opt_noblock_validity),
1797         fsparam_u32     ("inode_readahead_blks",
1798                                                 Opt_inode_readahead_blks),
1799         fsparam_u32     ("journal_ioprio",      Opt_journal_ioprio),
1800         fsparam_u32     ("auto_da_alloc",       Opt_auto_da_alloc),
1801         fsparam_flag    ("auto_da_alloc",       Opt_auto_da_alloc),
1802         fsparam_flag    ("noauto_da_alloc",     Opt_noauto_da_alloc),
1803         fsparam_flag    ("dioread_nolock",      Opt_dioread_nolock),
1804         fsparam_flag    ("nodioread_nolock",    Opt_dioread_lock),
1805         fsparam_flag    ("dioread_lock",        Opt_dioread_lock),
1806         fsparam_flag    ("discard",             Opt_discard),
1807         fsparam_flag    ("nodiscard",           Opt_nodiscard),
1808         fsparam_u32     ("init_itable",         Opt_init_itable),
1809         fsparam_flag    ("init_itable",         Opt_init_itable),
1810         fsparam_flag    ("noinit_itable",       Opt_noinit_itable),
1811 #ifdef CONFIG_EXT4_DEBUG
1812         fsparam_flag    ("fc_debug_force",      Opt_fc_debug_force),
1813         fsparam_u32     ("fc_debug_max_replay", Opt_fc_debug_max_replay),
1814 #endif
1815         fsparam_u32     ("max_dir_size_kb",     Opt_max_dir_size_kb),
1816         fsparam_flag    ("test_dummy_encryption",
1817                                                 Opt_test_dummy_encryption),
1818         fsparam_string  ("test_dummy_encryption",
1819                                                 Opt_test_dummy_encryption),
1820         fsparam_flag    ("inlinecrypt",         Opt_inlinecrypt),
1821         fsparam_flag    ("nombcache",           Opt_nombcache),
1822         fsparam_flag    ("no_mbcache",          Opt_nombcache), /* for backward compatibility */
1823         fsparam_flag    ("prefetch_block_bitmaps",
1824                                                 Opt_removed),
1825         fsparam_flag    ("no_prefetch_block_bitmaps",
1826                                                 Opt_no_prefetch_block_bitmaps),
1827         fsparam_s32     ("mb_optimize_scan",    Opt_mb_optimize_scan),
1828         fsparam_string  ("check",               Opt_removed),   /* mount option from ext2/3 */
1829         fsparam_flag    ("nocheck",             Opt_removed),   /* mount option from ext2/3 */
1830         fsparam_flag    ("reservation",         Opt_removed),   /* mount option from ext2/3 */
1831         fsparam_flag    ("noreservation",       Opt_removed),   /* mount option from ext2/3 */
1832         fsparam_u32     ("journal",             Opt_removed),   /* mount option from ext2/3 */
1833         {}
1834 };
1835
1836 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1837
1838 #define MOPT_SET        0x0001
1839 #define MOPT_CLEAR      0x0002
1840 #define MOPT_NOSUPPORT  0x0004
1841 #define MOPT_EXPLICIT   0x0008
1842 #ifdef CONFIG_QUOTA
1843 #define MOPT_Q          0
1844 #define MOPT_QFMT       0x0010
1845 #else
1846 #define MOPT_Q          MOPT_NOSUPPORT
1847 #define MOPT_QFMT       MOPT_NOSUPPORT
1848 #endif
1849 #define MOPT_NO_EXT2    0x0020
1850 #define MOPT_NO_EXT3    0x0040
1851 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1852 #define MOPT_SKIP       0x0080
1853 #define MOPT_2          0x0100
1854
1855 static const struct mount_opts {
1856         int     token;
1857         int     mount_opt;
1858         int     flags;
1859 } ext4_mount_opts[] = {
1860         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1861         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1862         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1863         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1864         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1865         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1866         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1867          MOPT_EXT4_ONLY | MOPT_SET},
1868         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1869          MOPT_EXT4_ONLY | MOPT_CLEAR},
1870         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1871         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1872         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1873          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1874         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1875          MOPT_EXT4_ONLY | MOPT_CLEAR},
1876         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1877         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1878         {Opt_commit, 0, MOPT_NO_EXT2},
1879         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1880          MOPT_EXT4_ONLY | MOPT_CLEAR},
1881         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1882          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1883         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1884                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1885          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1886         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1887         {Opt_data_err, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_NO_EXT2},
1888         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1889         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1890         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1891         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1892         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1893         {Opt_dax_type, 0, MOPT_EXT4_ONLY},
1894         {Opt_journal_dev, 0, MOPT_NO_EXT2},
1895         {Opt_journal_path, 0, MOPT_NO_EXT2},
1896         {Opt_journal_ioprio, 0, MOPT_NO_EXT2},
1897         {Opt_data, 0, MOPT_NO_EXT2},
1898         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1899 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1900         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1901 #else
1902         {Opt_acl, 0, MOPT_NOSUPPORT},
1903 #endif
1904         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1905         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1906         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1907         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1908                                                         MOPT_SET | MOPT_Q},
1909         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1910                                                         MOPT_SET | MOPT_Q},
1911         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1912                                                         MOPT_SET | MOPT_Q},
1913         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1914                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1915                                                         MOPT_CLEAR | MOPT_Q},
1916         {Opt_usrjquota, 0, MOPT_Q},
1917         {Opt_grpjquota, 0, MOPT_Q},
1918         {Opt_jqfmt, 0, MOPT_QFMT},
1919         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1920         {Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
1921          MOPT_SET},
1922 #ifdef CONFIG_EXT4_DEBUG
1923         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1924          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1925 #endif
1926         {Opt_abort, EXT4_MOUNT2_ABORT, MOPT_SET | MOPT_2},
1927         {Opt_err, 0, 0}
1928 };
1929
1930 #if IS_ENABLED(CONFIG_UNICODE)
1931 static const struct ext4_sb_encodings {
1932         __u16 magic;
1933         char *name;
1934         unsigned int version;
1935 } ext4_sb_encoding_map[] = {
1936         {EXT4_ENC_UTF8_12_1, "utf8", UNICODE_AGE(12, 1, 0)},
1937 };
1938
1939 static const struct ext4_sb_encodings *
1940 ext4_sb_read_encoding(const struct ext4_super_block *es)
1941 {
1942         __u16 magic = le16_to_cpu(es->s_encoding);
1943         int i;
1944
1945         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1946                 if (magic == ext4_sb_encoding_map[i].magic)
1947                         return &ext4_sb_encoding_map[i];
1948
1949         return NULL;
1950 }
1951 #endif
1952
1953 #define EXT4_SPEC_JQUOTA                        (1 <<  0)
1954 #define EXT4_SPEC_JQFMT                         (1 <<  1)
1955 #define EXT4_SPEC_DATAJ                         (1 <<  2)
1956 #define EXT4_SPEC_SB_BLOCK                      (1 <<  3)
1957 #define EXT4_SPEC_JOURNAL_DEV                   (1 <<  4)
1958 #define EXT4_SPEC_JOURNAL_IOPRIO                (1 <<  5)
1959 #define EXT4_SPEC_s_want_extra_isize            (1 <<  7)
1960 #define EXT4_SPEC_s_max_batch_time              (1 <<  8)
1961 #define EXT4_SPEC_s_min_batch_time              (1 <<  9)
1962 #define EXT4_SPEC_s_inode_readahead_blks        (1 << 10)
1963 #define EXT4_SPEC_s_li_wait_mult                (1 << 11)
1964 #define EXT4_SPEC_s_max_dir_size_kb             (1 << 12)
1965 #define EXT4_SPEC_s_stripe                      (1 << 13)
1966 #define EXT4_SPEC_s_resuid                      (1 << 14)
1967 #define EXT4_SPEC_s_resgid                      (1 << 15)
1968 #define EXT4_SPEC_s_commit_interval             (1 << 16)
1969 #define EXT4_SPEC_s_fc_debug_max_replay         (1 << 17)
1970 #define EXT4_SPEC_s_sb_block                    (1 << 18)
1971 #define EXT4_SPEC_mb_optimize_scan              (1 << 19)
1972
1973 struct ext4_fs_context {
1974         char            *s_qf_names[EXT4_MAXQUOTAS];
1975         struct fscrypt_dummy_policy dummy_enc_policy;
1976         int             s_jquota_fmt;   /* Format of quota to use */
1977 #ifdef CONFIG_EXT4_DEBUG
1978         int s_fc_debug_max_replay;
1979 #endif
1980         unsigned short  qname_spec;
1981         unsigned long   vals_s_flags;   /* Bits to set in s_flags */
1982         unsigned long   mask_s_flags;   /* Bits changed in s_flags */
1983         unsigned long   journal_devnum;
1984         unsigned long   s_commit_interval;
1985         unsigned long   s_stripe;
1986         unsigned int    s_inode_readahead_blks;
1987         unsigned int    s_want_extra_isize;
1988         unsigned int    s_li_wait_mult;
1989         unsigned int    s_max_dir_size_kb;
1990         unsigned int    journal_ioprio;
1991         unsigned int    vals_s_mount_opt;
1992         unsigned int    mask_s_mount_opt;
1993         unsigned int    vals_s_mount_opt2;
1994         unsigned int    mask_s_mount_opt2;
1995         unsigned int    opt_flags;      /* MOPT flags */
1996         unsigned int    spec;
1997         u32             s_max_batch_time;
1998         u32             s_min_batch_time;
1999         kuid_t          s_resuid;
2000         kgid_t          s_resgid;
2001         ext4_fsblk_t    s_sb_block;
2002 };
2003
2004 static void ext4_fc_free(struct fs_context *fc)
2005 {
2006         struct ext4_fs_context *ctx = fc->fs_private;
2007         int i;
2008
2009         if (!ctx)
2010                 return;
2011
2012         for (i = 0; i < EXT4_MAXQUOTAS; i++)
2013                 kfree(ctx->s_qf_names[i]);
2014
2015         fscrypt_free_dummy_policy(&ctx->dummy_enc_policy);
2016         kfree(ctx);
2017 }
2018
2019 int ext4_init_fs_context(struct fs_context *fc)
2020 {
2021         struct ext4_fs_context *ctx;
2022
2023         ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2024         if (!ctx)
2025                 return -ENOMEM;
2026
2027         fc->fs_private = ctx;
2028         fc->ops = &ext4_context_ops;
2029
2030         return 0;
2031 }
2032
2033 #ifdef CONFIG_QUOTA
2034 /*
2035  * Note the name of the specified quota file.
2036  */
2037 static int note_qf_name(struct fs_context *fc, int qtype,
2038                        struct fs_parameter *param)
2039 {
2040         struct ext4_fs_context *ctx = fc->fs_private;
2041         char *qname;
2042
2043         if (param->size < 1) {
2044                 ext4_msg(NULL, KERN_ERR, "Missing quota name");
2045                 return -EINVAL;
2046         }
2047         if (strchr(param->string, '/')) {
2048                 ext4_msg(NULL, KERN_ERR,
2049                          "quotafile must be on filesystem root");
2050                 return -EINVAL;
2051         }
2052         if (ctx->s_qf_names[qtype]) {
2053                 if (strcmp(ctx->s_qf_names[qtype], param->string) != 0) {
2054                         ext4_msg(NULL, KERN_ERR,
2055                                  "%s quota file already specified",
2056                                  QTYPE2NAME(qtype));
2057                         return -EINVAL;
2058                 }
2059                 return 0;
2060         }
2061
2062         qname = kmemdup_nul(param->string, param->size, GFP_KERNEL);
2063         if (!qname) {
2064                 ext4_msg(NULL, KERN_ERR,
2065                          "Not enough memory for storing quotafile name");
2066                 return -ENOMEM;
2067         }
2068         ctx->s_qf_names[qtype] = qname;
2069         ctx->qname_spec |= 1 << qtype;
2070         ctx->spec |= EXT4_SPEC_JQUOTA;
2071         return 0;
2072 }
2073
2074 /*
2075  * Clear the name of the specified quota file.
2076  */
2077 static int unnote_qf_name(struct fs_context *fc, int qtype)
2078 {
2079         struct ext4_fs_context *ctx = fc->fs_private;
2080
2081         if (ctx->s_qf_names[qtype])
2082                 kfree(ctx->s_qf_names[qtype]);
2083
2084         ctx->s_qf_names[qtype] = NULL;
2085         ctx->qname_spec |= 1 << qtype;
2086         ctx->spec |= EXT4_SPEC_JQUOTA;
2087         return 0;
2088 }
2089 #endif
2090
2091 static int ext4_parse_test_dummy_encryption(const struct fs_parameter *param,
2092                                             struct ext4_fs_context *ctx)
2093 {
2094         int err;
2095
2096         if (!IS_ENABLED(CONFIG_FS_ENCRYPTION)) {
2097                 ext4_msg(NULL, KERN_WARNING,
2098                          "test_dummy_encryption option not supported");
2099                 return -EINVAL;
2100         }
2101         err = fscrypt_parse_test_dummy_encryption(param,
2102                                                   &ctx->dummy_enc_policy);
2103         if (err == -EINVAL) {
2104                 ext4_msg(NULL, KERN_WARNING,
2105                          "Value of option \"%s\" is unrecognized", param->key);
2106         } else if (err == -EEXIST) {
2107                 ext4_msg(NULL, KERN_WARNING,
2108                          "Conflicting test_dummy_encryption options");
2109                 return -EINVAL;
2110         }
2111         return err;
2112 }
2113
2114 #define EXT4_SET_CTX(name)                                              \
2115 static inline void ctx_set_##name(struct ext4_fs_context *ctx,          \
2116                                   unsigned long flag)                   \
2117 {                                                                       \
2118         ctx->mask_s_##name |= flag;                                     \
2119         ctx->vals_s_##name |= flag;                                     \
2120 }
2121
2122 #define EXT4_CLEAR_CTX(name)                                            \
2123 static inline void ctx_clear_##name(struct ext4_fs_context *ctx,        \
2124                                     unsigned long flag)                 \
2125 {                                                                       \
2126         ctx->mask_s_##name |= flag;                                     \
2127         ctx->vals_s_##name &= ~flag;                                    \
2128 }
2129
2130 #define EXT4_TEST_CTX(name)                                             \
2131 static inline unsigned long                                             \
2132 ctx_test_##name(struct ext4_fs_context *ctx, unsigned long flag)        \
2133 {                                                                       \
2134         return (ctx->vals_s_##name & flag);                             \
2135 }
2136
2137 EXT4_SET_CTX(flags); /* set only */
2138 EXT4_SET_CTX(mount_opt);
2139 EXT4_CLEAR_CTX(mount_opt);
2140 EXT4_TEST_CTX(mount_opt);
2141 EXT4_SET_CTX(mount_opt2);
2142 EXT4_CLEAR_CTX(mount_opt2);
2143 EXT4_TEST_CTX(mount_opt2);
2144
2145 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
2146 {
2147         struct ext4_fs_context *ctx = fc->fs_private;
2148         struct fs_parse_result result;
2149         const struct mount_opts *m;
2150         int is_remount;
2151         kuid_t uid;
2152         kgid_t gid;
2153         int token;
2154
2155         token = fs_parse(fc, ext4_param_specs, param, &result);
2156         if (token < 0)
2157                 return token;
2158         is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2159
2160         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2161                 if (token == m->token)
2162                         break;
2163
2164         ctx->opt_flags |= m->flags;
2165
2166         if (m->flags & MOPT_EXPLICIT) {
2167                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2168                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_EXPLICIT_DELALLOC);
2169                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2170                         ctx_set_mount_opt2(ctx,
2171                                        EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM);
2172                 } else
2173                         return -EINVAL;
2174         }
2175
2176         if (m->flags & MOPT_NOSUPPORT) {
2177                 ext4_msg(NULL, KERN_ERR, "%s option not supported",
2178                          param->key);
2179                 return 0;
2180         }
2181
2182         switch (token) {
2183 #ifdef CONFIG_QUOTA
2184         case Opt_usrjquota:
2185                 if (!*param->string)
2186                         return unnote_qf_name(fc, USRQUOTA);
2187                 else
2188                         return note_qf_name(fc, USRQUOTA, param);
2189         case Opt_grpjquota:
2190                 if (!*param->string)
2191                         return unnote_qf_name(fc, GRPQUOTA);
2192                 else
2193                         return note_qf_name(fc, GRPQUOTA, param);
2194 #endif
2195         case Opt_sb:
2196                 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2197                         ext4_msg(NULL, KERN_WARNING,
2198                                  "Ignoring %s option on remount", param->key);
2199                 } else {
2200                         ctx->s_sb_block = result.uint_32;
2201                         ctx->spec |= EXT4_SPEC_s_sb_block;
2202                 }
2203                 return 0;
2204         case Opt_removed:
2205                 ext4_msg(NULL, KERN_WARNING, "Ignoring removed %s option",
2206                          param->key);
2207                 return 0;
2208         case Opt_inlinecrypt:
2209 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2210                 ctx_set_flags(ctx, SB_INLINECRYPT);
2211 #else
2212                 ext4_msg(NULL, KERN_ERR, "inline encryption not supported");
2213 #endif
2214                 return 0;
2215         case Opt_errors:
2216                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_ERRORS_MASK);
2217                 ctx_set_mount_opt(ctx, result.uint_32);
2218                 return 0;
2219 #ifdef CONFIG_QUOTA
2220         case Opt_jqfmt:
2221                 ctx->s_jquota_fmt = result.uint_32;
2222                 ctx->spec |= EXT4_SPEC_JQFMT;
2223                 return 0;
2224 #endif
2225         case Opt_data:
2226                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2227                 ctx_set_mount_opt(ctx, result.uint_32);
2228                 ctx->spec |= EXT4_SPEC_DATAJ;
2229                 return 0;
2230         case Opt_commit:
2231                 if (result.uint_32 == 0)
2232                         result.uint_32 = JBD2_DEFAULT_MAX_COMMIT_AGE;
2233                 else if (result.uint_32 > INT_MAX / HZ) {
2234                         ext4_msg(NULL, KERN_ERR,
2235                                  "Invalid commit interval %d, "
2236                                  "must be smaller than %d",
2237                                  result.uint_32, INT_MAX / HZ);
2238                         return -EINVAL;
2239                 }
2240                 ctx->s_commit_interval = HZ * result.uint_32;
2241                 ctx->spec |= EXT4_SPEC_s_commit_interval;
2242                 return 0;
2243         case Opt_debug_want_extra_isize:
2244                 if ((result.uint_32 & 1) || (result.uint_32 < 4)) {
2245                         ext4_msg(NULL, KERN_ERR,
2246                                  "Invalid want_extra_isize %d", result.uint_32);
2247                         return -EINVAL;
2248                 }
2249                 ctx->s_want_extra_isize = result.uint_32;
2250                 ctx->spec |= EXT4_SPEC_s_want_extra_isize;
2251                 return 0;
2252         case Opt_max_batch_time:
2253                 ctx->s_max_batch_time = result.uint_32;
2254                 ctx->spec |= EXT4_SPEC_s_max_batch_time;
2255                 return 0;
2256         case Opt_min_batch_time:
2257                 ctx->s_min_batch_time = result.uint_32;
2258                 ctx->spec |= EXT4_SPEC_s_min_batch_time;
2259                 return 0;
2260         case Opt_inode_readahead_blks:
2261                 if (result.uint_32 &&
2262                     (result.uint_32 > (1 << 30) ||
2263                      !is_power_of_2(result.uint_32))) {
2264                         ext4_msg(NULL, KERN_ERR,
2265                                  "EXT4-fs: inode_readahead_blks must be "
2266                                  "0 or a power of 2 smaller than 2^31");
2267                         return -EINVAL;
2268                 }
2269                 ctx->s_inode_readahead_blks = result.uint_32;
2270                 ctx->spec |= EXT4_SPEC_s_inode_readahead_blks;
2271                 return 0;
2272         case Opt_init_itable:
2273                 ctx_set_mount_opt(ctx, EXT4_MOUNT_INIT_INODE_TABLE);
2274                 ctx->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
2275                 if (param->type == fs_value_is_string)
2276                         ctx->s_li_wait_mult = result.uint_32;
2277                 ctx->spec |= EXT4_SPEC_s_li_wait_mult;
2278                 return 0;
2279         case Opt_max_dir_size_kb:
2280                 ctx->s_max_dir_size_kb = result.uint_32;
2281                 ctx->spec |= EXT4_SPEC_s_max_dir_size_kb;
2282                 return 0;
2283 #ifdef CONFIG_EXT4_DEBUG
2284         case Opt_fc_debug_max_replay:
2285                 ctx->s_fc_debug_max_replay = result.uint_32;
2286                 ctx->spec |= EXT4_SPEC_s_fc_debug_max_replay;
2287                 return 0;
2288 #endif
2289         case Opt_stripe:
2290                 ctx->s_stripe = result.uint_32;
2291                 ctx->spec |= EXT4_SPEC_s_stripe;
2292                 return 0;
2293         case Opt_resuid:
2294                 uid = make_kuid(current_user_ns(), result.uint_32);
2295                 if (!uid_valid(uid)) {
2296                         ext4_msg(NULL, KERN_ERR, "Invalid uid value %d",
2297                                  result.uint_32);
2298                         return -EINVAL;
2299                 }
2300                 ctx->s_resuid = uid;
2301                 ctx->spec |= EXT4_SPEC_s_resuid;
2302                 return 0;
2303         case Opt_resgid:
2304                 gid = make_kgid(current_user_ns(), result.uint_32);
2305                 if (!gid_valid(gid)) {
2306                         ext4_msg(NULL, KERN_ERR, "Invalid gid value %d",
2307                                  result.uint_32);
2308                         return -EINVAL;
2309                 }
2310                 ctx->s_resgid = gid;
2311                 ctx->spec |= EXT4_SPEC_s_resgid;
2312                 return 0;
2313         case Opt_journal_dev:
2314                 if (is_remount) {
2315                         ext4_msg(NULL, KERN_ERR,
2316                                  "Cannot specify journal on remount");
2317                         return -EINVAL;
2318                 }
2319                 ctx->journal_devnum = result.uint_32;
2320                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2321                 return 0;
2322         case Opt_journal_path:
2323         {
2324                 struct inode *journal_inode;
2325                 struct path path;
2326                 int error;
2327
2328                 if (is_remount) {
2329                         ext4_msg(NULL, KERN_ERR,
2330                                  "Cannot specify journal on remount");
2331                         return -EINVAL;
2332                 }
2333
2334                 error = fs_lookup_param(fc, param, 1, LOOKUP_FOLLOW, &path);
2335                 if (error) {
2336                         ext4_msg(NULL, KERN_ERR, "error: could not find "
2337                                  "journal device path");
2338                         return -EINVAL;
2339                 }
2340
2341                 journal_inode = d_inode(path.dentry);
2342                 ctx->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2343                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2344                 path_put(&path);
2345                 return 0;
2346         }
2347         case Opt_journal_ioprio:
2348                 if (result.uint_32 > 7) {
2349                         ext4_msg(NULL, KERN_ERR, "Invalid journal IO priority"
2350                                  " (must be 0-7)");
2351                         return -EINVAL;
2352                 }
2353                 ctx->journal_ioprio =
2354                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, result.uint_32);
2355                 ctx->spec |= EXT4_SPEC_JOURNAL_IOPRIO;
2356                 return 0;
2357         case Opt_test_dummy_encryption:
2358                 return ext4_parse_test_dummy_encryption(param, ctx);
2359         case Opt_dax:
2360         case Opt_dax_type:
2361 #ifdef CONFIG_FS_DAX
2362         {
2363                 int type = (token == Opt_dax) ?
2364                            Opt_dax : result.uint_32;
2365
2366                 switch (type) {
2367                 case Opt_dax:
2368                 case Opt_dax_always:
2369                         ctx_set_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2370                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2371                         break;
2372                 case Opt_dax_never:
2373                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2374                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2375                         break;
2376                 case Opt_dax_inode:
2377                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2378                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2379                         /* Strictly for printing options */
2380                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE);
2381                         break;
2382                 }
2383                 return 0;
2384         }
2385 #else
2386                 ext4_msg(NULL, KERN_INFO, "dax option not supported");
2387                 return -EINVAL;
2388 #endif
2389         case Opt_data_err:
2390                 if (result.uint_32 == Opt_data_err_abort)
2391                         ctx_set_mount_opt(ctx, m->mount_opt);
2392                 else if (result.uint_32 == Opt_data_err_ignore)
2393                         ctx_clear_mount_opt(ctx, m->mount_opt);
2394                 return 0;
2395         case Opt_mb_optimize_scan:
2396                 if (result.int_32 == 1) {
2397                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2398                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2399                 } else if (result.int_32 == 0) {
2400                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2401                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2402                 } else {
2403                         ext4_msg(NULL, KERN_WARNING,
2404                                  "mb_optimize_scan should be set to 0 or 1.");
2405                         return -EINVAL;
2406                 }
2407                 return 0;
2408         }
2409
2410         /*
2411          * At this point we should only be getting options requiring MOPT_SET,
2412          * or MOPT_CLEAR. Anything else is a bug
2413          */
2414         if (m->token == Opt_err) {
2415                 ext4_msg(NULL, KERN_WARNING, "buggy handling of option %s",
2416                          param->key);
2417                 WARN_ON(1);
2418                 return -EINVAL;
2419         }
2420
2421         else {
2422                 unsigned int set = 0;
2423
2424                 if ((param->type == fs_value_is_flag) ||
2425                     result.uint_32 > 0)
2426                         set = 1;
2427
2428                 if (m->flags & MOPT_CLEAR)
2429                         set = !set;
2430                 else if (unlikely(!(m->flags & MOPT_SET))) {
2431                         ext4_msg(NULL, KERN_WARNING,
2432                                  "buggy handling of option %s",
2433                                  param->key);
2434                         WARN_ON(1);
2435                         return -EINVAL;
2436                 }
2437                 if (m->flags & MOPT_2) {
2438                         if (set != 0)
2439                                 ctx_set_mount_opt2(ctx, m->mount_opt);
2440                         else
2441                                 ctx_clear_mount_opt2(ctx, m->mount_opt);
2442                 } else {
2443                         if (set != 0)
2444                                 ctx_set_mount_opt(ctx, m->mount_opt);
2445                         else
2446                                 ctx_clear_mount_opt(ctx, m->mount_opt);
2447                 }
2448         }
2449
2450         return 0;
2451 }
2452
2453 static int parse_options(struct fs_context *fc, char *options)
2454 {
2455         struct fs_parameter param;
2456         int ret;
2457         char *key;
2458
2459         if (!options)
2460                 return 0;
2461
2462         while ((key = strsep(&options, ",")) != NULL) {
2463                 if (*key) {
2464                         size_t v_len = 0;
2465                         char *value = strchr(key, '=');
2466
2467                         param.type = fs_value_is_flag;
2468                         param.string = NULL;
2469
2470                         if (value) {
2471                                 if (value == key)
2472                                         continue;
2473
2474                                 *value++ = 0;
2475                                 v_len = strlen(value);
2476                                 param.string = kmemdup_nul(value, v_len,
2477                                                            GFP_KERNEL);
2478                                 if (!param.string)
2479                                         return -ENOMEM;
2480                                 param.type = fs_value_is_string;
2481                         }
2482
2483                         param.key = key;
2484                         param.size = v_len;
2485
2486                         ret = ext4_parse_param(fc, &param);
2487                         if (param.string)
2488                                 kfree(param.string);
2489                         if (ret < 0)
2490                                 return ret;
2491                 }
2492         }
2493
2494         ret = ext4_validate_options(fc);
2495         if (ret < 0)
2496                 return ret;
2497
2498         return 0;
2499 }
2500
2501 static int parse_apply_sb_mount_options(struct super_block *sb,
2502                                         struct ext4_fs_context *m_ctx)
2503 {
2504         struct ext4_sb_info *sbi = EXT4_SB(sb);
2505         char *s_mount_opts = NULL;
2506         struct ext4_fs_context *s_ctx = NULL;
2507         struct fs_context *fc = NULL;
2508         int ret = -ENOMEM;
2509
2510         if (!sbi->s_es->s_mount_opts[0])
2511                 return 0;
2512
2513         s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
2514                                 sizeof(sbi->s_es->s_mount_opts),
2515                                 GFP_KERNEL);
2516         if (!s_mount_opts)
2517                 return ret;
2518
2519         fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
2520         if (!fc)
2521                 goto out_free;
2522
2523         s_ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2524         if (!s_ctx)
2525                 goto out_free;
2526
2527         fc->fs_private = s_ctx;
2528         fc->s_fs_info = sbi;
2529
2530         ret = parse_options(fc, s_mount_opts);
2531         if (ret < 0)
2532                 goto parse_failed;
2533
2534         ret = ext4_check_opt_consistency(fc, sb);
2535         if (ret < 0) {
2536 parse_failed:
2537                 ext4_msg(sb, KERN_WARNING,
2538                          "failed to parse options in superblock: %s",
2539                          s_mount_opts);
2540                 ret = 0;
2541                 goto out_free;
2542         }
2543
2544         if (s_ctx->spec & EXT4_SPEC_JOURNAL_DEV)
2545                 m_ctx->journal_devnum = s_ctx->journal_devnum;
2546         if (s_ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)
2547                 m_ctx->journal_ioprio = s_ctx->journal_ioprio;
2548
2549         ext4_apply_options(fc, sb);
2550         ret = 0;
2551
2552 out_free:
2553         if (fc) {
2554                 ext4_fc_free(fc);
2555                 kfree(fc);
2556         }
2557         kfree(s_mount_opts);
2558         return ret;
2559 }
2560
2561 static void ext4_apply_quota_options(struct fs_context *fc,
2562                                      struct super_block *sb)
2563 {
2564 #ifdef CONFIG_QUOTA
2565         bool quota_feature = ext4_has_feature_quota(sb);
2566         struct ext4_fs_context *ctx = fc->fs_private;
2567         struct ext4_sb_info *sbi = EXT4_SB(sb);
2568         char *qname;
2569         int i;
2570
2571         if (quota_feature)
2572                 return;
2573
2574         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2575                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2576                         if (!(ctx->qname_spec & (1 << i)))
2577                                 continue;
2578
2579                         qname = ctx->s_qf_names[i]; /* May be NULL */
2580                         if (qname)
2581                                 set_opt(sb, QUOTA);
2582                         ctx->s_qf_names[i] = NULL;
2583                         qname = rcu_replace_pointer(sbi->s_qf_names[i], qname,
2584                                                 lockdep_is_held(&sb->s_umount));
2585                         if (qname)
2586                                 kfree_rcu_mightsleep(qname);
2587                 }
2588         }
2589
2590         if (ctx->spec & EXT4_SPEC_JQFMT)
2591                 sbi->s_jquota_fmt = ctx->s_jquota_fmt;
2592 #endif
2593 }
2594
2595 /*
2596  * Check quota settings consistency.
2597  */
2598 static int ext4_check_quota_consistency(struct fs_context *fc,
2599                                         struct super_block *sb)
2600 {
2601 #ifdef CONFIG_QUOTA
2602         struct ext4_fs_context *ctx = fc->fs_private;
2603         struct ext4_sb_info *sbi = EXT4_SB(sb);
2604         bool quota_feature = ext4_has_feature_quota(sb);
2605         bool quota_loaded = sb_any_quota_loaded(sb);
2606         bool usr_qf_name, grp_qf_name, usrquota, grpquota;
2607         int quota_flags, i;
2608
2609         /*
2610          * We do the test below only for project quotas. 'usrquota' and
2611          * 'grpquota' mount options are allowed even without quota feature
2612          * to support legacy quotas in quota files.
2613          */
2614         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_PRJQUOTA) &&
2615             !ext4_has_feature_project(sb)) {
2616                 ext4_msg(NULL, KERN_ERR, "Project quota feature not enabled. "
2617                          "Cannot enable project quota enforcement.");
2618                 return -EINVAL;
2619         }
2620
2621         quota_flags = EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2622                       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA;
2623         if (quota_loaded &&
2624             ctx->mask_s_mount_opt & quota_flags &&
2625             !ctx_test_mount_opt(ctx, quota_flags))
2626                 goto err_quota_change;
2627
2628         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2629
2630                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2631                         if (!(ctx->qname_spec & (1 << i)))
2632                                 continue;
2633
2634                         if (quota_loaded &&
2635                             !!sbi->s_qf_names[i] != !!ctx->s_qf_names[i])
2636                                 goto err_jquota_change;
2637
2638                         if (sbi->s_qf_names[i] && ctx->s_qf_names[i] &&
2639                             strcmp(get_qf_name(sb, sbi, i),
2640                                    ctx->s_qf_names[i]) != 0)
2641                                 goto err_jquota_specified;
2642                 }
2643
2644                 if (quota_feature) {
2645                         ext4_msg(NULL, KERN_INFO,
2646                                  "Journaled quota options ignored when "
2647                                  "QUOTA feature is enabled");
2648                         return 0;
2649                 }
2650         }
2651
2652         if (ctx->spec & EXT4_SPEC_JQFMT) {
2653                 if (sbi->s_jquota_fmt != ctx->s_jquota_fmt && quota_loaded)
2654                         goto err_jquota_change;
2655                 if (quota_feature) {
2656                         ext4_msg(NULL, KERN_INFO, "Quota format mount options "
2657                                  "ignored when QUOTA feature is enabled");
2658                         return 0;
2659                 }
2660         }
2661
2662         /* Make sure we don't mix old and new quota format */
2663         usr_qf_name = (get_qf_name(sb, sbi, USRQUOTA) ||
2664                        ctx->s_qf_names[USRQUOTA]);
2665         grp_qf_name = (get_qf_name(sb, sbi, GRPQUOTA) ||
2666                        ctx->s_qf_names[GRPQUOTA]);
2667
2668         usrquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2669                     test_opt(sb, USRQUOTA));
2670
2671         grpquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) ||
2672                     test_opt(sb, GRPQUOTA));
2673
2674         if (usr_qf_name) {
2675                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2676                 usrquota = false;
2677         }
2678         if (grp_qf_name) {
2679                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2680                 grpquota = false;
2681         }
2682
2683         if (usr_qf_name || grp_qf_name) {
2684                 if (usrquota || grpquota) {
2685                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2686                                  "format mixing");
2687                         return -EINVAL;
2688                 }
2689
2690                 if (!(ctx->spec & EXT4_SPEC_JQFMT || sbi->s_jquota_fmt)) {
2691                         ext4_msg(NULL, KERN_ERR, "journaled quota format "
2692                                  "not specified");
2693                         return -EINVAL;
2694                 }
2695         }
2696
2697         return 0;
2698
2699 err_quota_change:
2700         ext4_msg(NULL, KERN_ERR,
2701                  "Cannot change quota options when quota turned on");
2702         return -EINVAL;
2703 err_jquota_change:
2704         ext4_msg(NULL, KERN_ERR, "Cannot change journaled quota "
2705                  "options when quota turned on");
2706         return -EINVAL;
2707 err_jquota_specified:
2708         ext4_msg(NULL, KERN_ERR, "%s quota file already specified",
2709                  QTYPE2NAME(i));
2710         return -EINVAL;
2711 #else
2712         return 0;
2713 #endif
2714 }
2715
2716 static int ext4_check_test_dummy_encryption(const struct fs_context *fc,
2717                                             struct super_block *sb)
2718 {
2719         const struct ext4_fs_context *ctx = fc->fs_private;
2720         const struct ext4_sb_info *sbi = EXT4_SB(sb);
2721
2722         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy))
2723                 return 0;
2724
2725         if (!ext4_has_feature_encrypt(sb)) {
2726                 ext4_msg(NULL, KERN_WARNING,
2727                          "test_dummy_encryption requires encrypt feature");
2728                 return -EINVAL;
2729         }
2730         /*
2731          * This mount option is just for testing, and it's not worthwhile to
2732          * implement the extra complexity (e.g. RCU protection) that would be
2733          * needed to allow it to be set or changed during remount.  We do allow
2734          * it to be specified during remount, but only if there is no change.
2735          */
2736         if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2737                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2738                                                  &ctx->dummy_enc_policy))
2739                         return 0;
2740                 ext4_msg(NULL, KERN_WARNING,
2741                          "Can't set or change test_dummy_encryption on remount");
2742                 return -EINVAL;
2743         }
2744         /* Also make sure s_mount_opts didn't contain a conflicting value. */
2745         if (fscrypt_is_dummy_policy_set(&sbi->s_dummy_enc_policy)) {
2746                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2747                                                  &ctx->dummy_enc_policy))
2748                         return 0;
2749                 ext4_msg(NULL, KERN_WARNING,
2750                          "Conflicting test_dummy_encryption options");
2751                 return -EINVAL;
2752         }
2753         return 0;
2754 }
2755
2756 static void ext4_apply_test_dummy_encryption(struct ext4_fs_context *ctx,
2757                                              struct super_block *sb)
2758 {
2759         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy) ||
2760             /* if already set, it was already verified to be the same */
2761             fscrypt_is_dummy_policy_set(&EXT4_SB(sb)->s_dummy_enc_policy))
2762                 return;
2763         EXT4_SB(sb)->s_dummy_enc_policy = ctx->dummy_enc_policy;
2764         memset(&ctx->dummy_enc_policy, 0, sizeof(ctx->dummy_enc_policy));
2765         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2766 }
2767
2768 static int ext4_check_opt_consistency(struct fs_context *fc,
2769                                       struct super_block *sb)
2770 {
2771         struct ext4_fs_context *ctx = fc->fs_private;
2772         struct ext4_sb_info *sbi = fc->s_fs_info;
2773         int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2774         int err;
2775
2776         if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2777                 ext4_msg(NULL, KERN_ERR,
2778                          "Mount option(s) incompatible with ext2");
2779                 return -EINVAL;
2780         }
2781         if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2782                 ext4_msg(NULL, KERN_ERR,
2783                          "Mount option(s) incompatible with ext3");
2784                 return -EINVAL;
2785         }
2786
2787         if (ctx->s_want_extra_isize >
2788             (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2789                 ext4_msg(NULL, KERN_ERR,
2790                          "Invalid want_extra_isize %d",
2791                          ctx->s_want_extra_isize);
2792                 return -EINVAL;
2793         }
2794
2795         err = ext4_check_test_dummy_encryption(fc, sb);
2796         if (err)
2797                 return err;
2798
2799         if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2800                 if (!sbi->s_journal) {
2801                         ext4_msg(NULL, KERN_WARNING,
2802                                  "Remounting file system with no journal "
2803                                  "so ignoring journalled data option");
2804                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2805                 } else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2806                            test_opt(sb, DATA_FLAGS)) {
2807                         ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2808                                  "on remount");
2809                         return -EINVAL;
2810                 }
2811         }
2812
2813         if (is_remount) {
2814                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2815                     (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2816                         ext4_msg(NULL, KERN_ERR, "can't mount with "
2817                                  "both data=journal and dax");
2818                         return -EINVAL;
2819                 }
2820
2821                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2822                     (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2823                      (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2824 fail_dax_change_remount:
2825                         ext4_msg(NULL, KERN_ERR, "can't change "
2826                                  "dax mount option while remounting");
2827                         return -EINVAL;
2828                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2829                          (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2830                           (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2831                         goto fail_dax_change_remount;
2832                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2833                            ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2834                             (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2835                             !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2836                         goto fail_dax_change_remount;
2837                 }
2838         }
2839
2840         return ext4_check_quota_consistency(fc, sb);
2841 }
2842
2843 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2844 {
2845         struct ext4_fs_context *ctx = fc->fs_private;
2846         struct ext4_sb_info *sbi = fc->s_fs_info;
2847
2848         sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2849         sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2850         sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2851         sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2852         sb->s_flags &= ~ctx->mask_s_flags;
2853         sb->s_flags |= ctx->vals_s_flags;
2854
2855 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2856         APPLY(s_commit_interval);
2857         APPLY(s_stripe);
2858         APPLY(s_max_batch_time);
2859         APPLY(s_min_batch_time);
2860         APPLY(s_want_extra_isize);
2861         APPLY(s_inode_readahead_blks);
2862         APPLY(s_max_dir_size_kb);
2863         APPLY(s_li_wait_mult);
2864         APPLY(s_resgid);
2865         APPLY(s_resuid);
2866
2867 #ifdef CONFIG_EXT4_DEBUG
2868         APPLY(s_fc_debug_max_replay);
2869 #endif
2870
2871         ext4_apply_quota_options(fc, sb);
2872         ext4_apply_test_dummy_encryption(ctx, sb);
2873 }
2874
2875
2876 static int ext4_validate_options(struct fs_context *fc)
2877 {
2878 #ifdef CONFIG_QUOTA
2879         struct ext4_fs_context *ctx = fc->fs_private;
2880         char *usr_qf_name, *grp_qf_name;
2881
2882         usr_qf_name = ctx->s_qf_names[USRQUOTA];
2883         grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2884
2885         if (usr_qf_name || grp_qf_name) {
2886                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2887                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2888
2889                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2890                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2891
2892                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2893                     ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2894                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2895                                  "format mixing");
2896                         return -EINVAL;
2897                 }
2898         }
2899 #endif
2900         return 1;
2901 }
2902
2903 static inline void ext4_show_quota_options(struct seq_file *seq,
2904                                            struct super_block *sb)
2905 {
2906 #if defined(CONFIG_QUOTA)
2907         struct ext4_sb_info *sbi = EXT4_SB(sb);
2908         char *usr_qf_name, *grp_qf_name;
2909
2910         if (sbi->s_jquota_fmt) {
2911                 char *fmtname = "";
2912
2913                 switch (sbi->s_jquota_fmt) {
2914                 case QFMT_VFS_OLD:
2915                         fmtname = "vfsold";
2916                         break;
2917                 case QFMT_VFS_V0:
2918                         fmtname = "vfsv0";
2919                         break;
2920                 case QFMT_VFS_V1:
2921                         fmtname = "vfsv1";
2922                         break;
2923                 }
2924                 seq_printf(seq, ",jqfmt=%s", fmtname);
2925         }
2926
2927         rcu_read_lock();
2928         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2929         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2930         if (usr_qf_name)
2931                 seq_show_option(seq, "usrjquota", usr_qf_name);
2932         if (grp_qf_name)
2933                 seq_show_option(seq, "grpjquota", grp_qf_name);
2934         rcu_read_unlock();
2935 #endif
2936 }
2937
2938 static const char *token2str(int token)
2939 {
2940         const struct fs_parameter_spec *spec;
2941
2942         for (spec = ext4_param_specs; spec->name != NULL; spec++)
2943                 if (spec->opt == token && !spec->type)
2944                         break;
2945         return spec->name;
2946 }
2947
2948 /*
2949  * Show an option if
2950  *  - it's set to a non-default value OR
2951  *  - if the per-sb default is different from the global default
2952  */
2953 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2954                               int nodefs)
2955 {
2956         struct ext4_sb_info *sbi = EXT4_SB(sb);
2957         struct ext4_super_block *es = sbi->s_es;
2958         int def_errors;
2959         const struct mount_opts *m;
2960         char sep = nodefs ? '\n' : ',';
2961
2962 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2963 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2964
2965         if (sbi->s_sb_block != 1)
2966                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2967
2968         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2969                 int want_set = m->flags & MOPT_SET;
2970                 int opt_2 = m->flags & MOPT_2;
2971                 unsigned int mount_opt, def_mount_opt;
2972
2973                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2974                     m->flags & MOPT_SKIP)
2975                         continue;
2976
2977                 if (opt_2) {
2978                         mount_opt = sbi->s_mount_opt2;
2979                         def_mount_opt = sbi->s_def_mount_opt2;
2980                 } else {
2981                         mount_opt = sbi->s_mount_opt;
2982                         def_mount_opt = sbi->s_def_mount_opt;
2983                 }
2984                 /* skip if same as the default */
2985                 if (!nodefs && !(m->mount_opt & (mount_opt ^ def_mount_opt)))
2986                         continue;
2987                 /* select Opt_noFoo vs Opt_Foo */
2988                 if ((want_set &&
2989                      (mount_opt & m->mount_opt) != m->mount_opt) ||
2990                     (!want_set && (mount_opt & m->mount_opt)))
2991                         continue;
2992                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2993         }
2994
2995         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2996             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2997                 SEQ_OPTS_PRINT("resuid=%u",
2998                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2999         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
3000             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
3001                 SEQ_OPTS_PRINT("resgid=%u",
3002                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
3003         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
3004         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
3005                 SEQ_OPTS_PUTS("errors=remount-ro");
3006         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
3007                 SEQ_OPTS_PUTS("errors=continue");
3008         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
3009                 SEQ_OPTS_PUTS("errors=panic");
3010         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
3011                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
3012         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
3013                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
3014         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
3015                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
3016         if (nodefs || sbi->s_stripe)
3017                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
3018         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
3019                         (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
3020                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3021                         SEQ_OPTS_PUTS("data=journal");
3022                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3023                         SEQ_OPTS_PUTS("data=ordered");
3024                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
3025                         SEQ_OPTS_PUTS("data=writeback");
3026         }
3027         if (nodefs ||
3028             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
3029                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
3030                                sbi->s_inode_readahead_blks);
3031
3032         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
3033                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
3034                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
3035         if (nodefs || sbi->s_max_dir_size_kb)
3036                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
3037         if (test_opt(sb, DATA_ERR_ABORT))
3038                 SEQ_OPTS_PUTS("data_err=abort");
3039
3040         fscrypt_show_test_dummy_encryption(seq, sep, sb);
3041
3042         if (sb->s_flags & SB_INLINECRYPT)
3043                 SEQ_OPTS_PUTS("inlinecrypt");
3044
3045         if (test_opt(sb, DAX_ALWAYS)) {
3046                 if (IS_EXT2_SB(sb))
3047                         SEQ_OPTS_PUTS("dax");
3048                 else
3049                         SEQ_OPTS_PUTS("dax=always");
3050         } else if (test_opt2(sb, DAX_NEVER)) {
3051                 SEQ_OPTS_PUTS("dax=never");
3052         } else if (test_opt2(sb, DAX_INODE)) {
3053                 SEQ_OPTS_PUTS("dax=inode");
3054         }
3055
3056         if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3057                         !test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3058                 SEQ_OPTS_PUTS("mb_optimize_scan=0");
3059         } else if (sbi->s_groups_count < MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3060                         test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3061                 SEQ_OPTS_PUTS("mb_optimize_scan=1");
3062         }
3063
3064         ext4_show_quota_options(seq, sb);
3065         return 0;
3066 }
3067
3068 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
3069 {
3070         return _ext4_show_options(seq, root->d_sb, 0);
3071 }
3072
3073 int ext4_seq_options_show(struct seq_file *seq, void *offset)
3074 {
3075         struct super_block *sb = seq->private;
3076         int rc;
3077
3078         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
3079         rc = _ext4_show_options(seq, sb, 1);
3080         seq_puts(seq, "\n");
3081         return rc;
3082 }
3083
3084 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3085                             int read_only)
3086 {
3087         struct ext4_sb_info *sbi = EXT4_SB(sb);
3088         int err = 0;
3089
3090         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3091                 ext4_msg(sb, KERN_ERR, "revision level too high, "
3092                          "forcing read-only mode");
3093                 err = -EROFS;
3094                 goto done;
3095         }
3096         if (read_only)
3097                 goto done;
3098         if (!(sbi->s_mount_state & EXT4_VALID_FS))
3099                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3100                          "running e2fsck is recommended");
3101         else if (sbi->s_mount_state & EXT4_ERROR_FS)
3102                 ext4_msg(sb, KERN_WARNING,
3103                          "warning: mounting fs with errors, "
3104                          "running e2fsck is recommended");
3105         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3106                  le16_to_cpu(es->s_mnt_count) >=
3107                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3108                 ext4_msg(sb, KERN_WARNING,
3109                          "warning: maximal mount count reached, "
3110                          "running e2fsck is recommended");
3111         else if (le32_to_cpu(es->s_checkinterval) &&
3112                  (ext4_get_tstamp(es, s_lastcheck) +
3113                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3114                 ext4_msg(sb, KERN_WARNING,
3115                          "warning: checktime reached, "
3116                          "running e2fsck is recommended");
3117         if (!sbi->s_journal)
3118                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3119         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3120                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3121         le16_add_cpu(&es->s_mnt_count, 1);
3122         ext4_update_tstamp(es, s_mtime);
3123         if (sbi->s_journal) {
3124                 ext4_set_feature_journal_needs_recovery(sb);
3125                 if (ext4_has_feature_orphan_file(sb))
3126                         ext4_set_feature_orphan_present(sb);
3127         }
3128
3129         err = ext4_commit_super(sb);
3130 done:
3131         if (test_opt(sb, DEBUG))
3132                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3133                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3134                         sb->s_blocksize,
3135                         sbi->s_groups_count,
3136                         EXT4_BLOCKS_PER_GROUP(sb),
3137                         EXT4_INODES_PER_GROUP(sb),
3138                         sbi->s_mount_opt, sbi->s_mount_opt2);
3139         return err;
3140 }
3141
3142 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3143 {
3144         struct ext4_sb_info *sbi = EXT4_SB(sb);
3145         struct flex_groups **old_groups, **new_groups;
3146         int size, i, j;
3147
3148         if (!sbi->s_log_groups_per_flex)
3149                 return 0;
3150
3151         size = ext4_flex_group(sbi, ngroup - 1) + 1;
3152         if (size <= sbi->s_flex_groups_allocated)
3153                 return 0;
3154
3155         new_groups = kvzalloc(roundup_pow_of_two(size *
3156                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3157         if (!new_groups) {
3158                 ext4_msg(sb, KERN_ERR,
3159                          "not enough memory for %d flex group pointers", size);
3160                 return -ENOMEM;
3161         }
3162         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3163                 new_groups[i] = kvzalloc(roundup_pow_of_two(
3164                                          sizeof(struct flex_groups)),
3165                                          GFP_KERNEL);
3166                 if (!new_groups[i]) {
3167                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
3168                                 kvfree(new_groups[j]);
3169                         kvfree(new_groups);
3170                         ext4_msg(sb, KERN_ERR,
3171                                  "not enough memory for %d flex groups", size);
3172                         return -ENOMEM;
3173                 }
3174         }
3175         rcu_read_lock();
3176         old_groups = rcu_dereference(sbi->s_flex_groups);
3177         if (old_groups)
3178                 memcpy(new_groups, old_groups,
3179                        (sbi->s_flex_groups_allocated *
3180                         sizeof(struct flex_groups *)));
3181         rcu_read_unlock();
3182         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3183         sbi->s_flex_groups_allocated = size;
3184         if (old_groups)
3185                 ext4_kvfree_array_rcu(old_groups);
3186         return 0;
3187 }
3188
3189 static int ext4_fill_flex_info(struct super_block *sb)
3190 {
3191         struct ext4_sb_info *sbi = EXT4_SB(sb);
3192         struct ext4_group_desc *gdp = NULL;
3193         struct flex_groups *fg;
3194         ext4_group_t flex_group;
3195         int i, err;
3196
3197         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3198         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3199                 sbi->s_log_groups_per_flex = 0;
3200                 return 1;
3201         }
3202
3203         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3204         if (err)
3205                 goto failed;
3206
3207         for (i = 0; i < sbi->s_groups_count; i++) {
3208                 gdp = ext4_get_group_desc(sb, i, NULL);
3209
3210                 flex_group = ext4_flex_group(sbi, i);
3211                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3212                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3213                 atomic64_add(ext4_free_group_clusters(sb, gdp),
3214                              &fg->free_clusters);
3215                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3216         }
3217
3218         return 1;
3219 failed:
3220         return 0;
3221 }
3222
3223 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3224                                    struct ext4_group_desc *gdp)
3225 {
3226         int offset = offsetof(struct ext4_group_desc, bg_checksum);
3227         __u16 crc = 0;
3228         __le32 le_group = cpu_to_le32(block_group);
3229         struct ext4_sb_info *sbi = EXT4_SB(sb);
3230
3231         if (ext4_has_metadata_csum(sbi->s_sb)) {
3232                 /* Use new metadata_csum algorithm */
3233                 __u32 csum32;
3234                 __u16 dummy_csum = 0;
3235
3236                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
3237                                      sizeof(le_group));
3238                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
3239                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
3240                                      sizeof(dummy_csum));
3241                 offset += sizeof(dummy_csum);
3242                 if (offset < sbi->s_desc_size)
3243                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
3244                                              sbi->s_desc_size - offset);
3245
3246                 crc = csum32 & 0xFFFF;
3247                 goto out;
3248         }
3249
3250         /* old crc16 code */
3251         if (!ext4_has_feature_gdt_csum(sb))
3252                 return 0;
3253
3254         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3255         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3256         crc = crc16(crc, (__u8 *)gdp, offset);
3257         offset += sizeof(gdp->bg_checksum); /* skip checksum */
3258         /* for checksum of struct ext4_group_desc do the rest...*/
3259         if (ext4_has_feature_64bit(sb) && offset < sbi->s_desc_size)
3260                 crc = crc16(crc, (__u8 *)gdp + offset,
3261                             sbi->s_desc_size - offset);
3262
3263 out:
3264         return cpu_to_le16(crc);
3265 }
3266
3267 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3268                                 struct ext4_group_desc *gdp)
3269 {
3270         if (ext4_has_group_desc_csum(sb) &&
3271             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3272                 return 0;
3273
3274         return 1;
3275 }
3276
3277 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3278                               struct ext4_group_desc *gdp)
3279 {
3280         if (!ext4_has_group_desc_csum(sb))
3281                 return;
3282         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3283 }
3284
3285 /* Called at mount-time, super-block is locked */
3286 static int ext4_check_descriptors(struct super_block *sb,
3287                                   ext4_fsblk_t sb_block,
3288                                   ext4_group_t *first_not_zeroed)
3289 {
3290         struct ext4_sb_info *sbi = EXT4_SB(sb);
3291         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3292         ext4_fsblk_t last_block;
3293         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3294         ext4_fsblk_t block_bitmap;
3295         ext4_fsblk_t inode_bitmap;
3296         ext4_fsblk_t inode_table;
3297         int flexbg_flag = 0;
3298         ext4_group_t i, grp = sbi->s_groups_count;
3299
3300         if (ext4_has_feature_flex_bg(sb))
3301                 flexbg_flag = 1;
3302
3303         ext4_debug("Checking group descriptors");
3304
3305         for (i = 0; i < sbi->s_groups_count; i++) {
3306                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3307
3308                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
3309                         last_block = ext4_blocks_count(sbi->s_es) - 1;
3310                 else
3311                         last_block = first_block +
3312                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
3313
3314                 if ((grp == sbi->s_groups_count) &&
3315                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3316                         grp = i;
3317
3318                 block_bitmap = ext4_block_bitmap(sb, gdp);
3319                 if (block_bitmap == sb_block) {
3320                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3321                                  "Block bitmap for group %u overlaps "
3322                                  "superblock", i);
3323                         if (!sb_rdonly(sb))
3324                                 return 0;
3325                 }
3326                 if (block_bitmap >= sb_block + 1 &&
3327                     block_bitmap <= last_bg_block) {
3328                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3329                                  "Block bitmap for group %u overlaps "
3330                                  "block group descriptors", i);
3331                         if (!sb_rdonly(sb))
3332                                 return 0;
3333                 }
3334                 if (block_bitmap < first_block || block_bitmap > last_block) {
3335                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3336                                "Block bitmap for group %u not in group "
3337                                "(block %llu)!", i, block_bitmap);
3338                         return 0;
3339                 }
3340                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
3341                 if (inode_bitmap == sb_block) {
3342                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3343                                  "Inode bitmap for group %u overlaps "
3344                                  "superblock", i);
3345                         if (!sb_rdonly(sb))
3346                                 return 0;
3347                 }
3348                 if (inode_bitmap >= sb_block + 1 &&
3349                     inode_bitmap <= last_bg_block) {
3350                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3351                                  "Inode bitmap for group %u overlaps "
3352                                  "block group descriptors", i);
3353                         if (!sb_rdonly(sb))
3354                                 return 0;
3355                 }
3356                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
3357                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3358                                "Inode bitmap for group %u not in group "
3359                                "(block %llu)!", i, inode_bitmap);
3360                         return 0;
3361                 }
3362                 inode_table = ext4_inode_table(sb, gdp);
3363                 if (inode_table == sb_block) {
3364                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3365                                  "Inode table for group %u overlaps "
3366                                  "superblock", i);
3367                         if (!sb_rdonly(sb))
3368                                 return 0;
3369                 }
3370                 if (inode_table >= sb_block + 1 &&
3371                     inode_table <= last_bg_block) {
3372                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3373                                  "Inode table for group %u overlaps "
3374                                  "block group descriptors", i);
3375                         if (!sb_rdonly(sb))
3376                                 return 0;
3377                 }
3378                 if (inode_table < first_block ||
3379                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
3380                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3381                                "Inode table for group %u not in group "
3382                                "(block %llu)!", i, inode_table);
3383                         return 0;
3384                 }
3385                 ext4_lock_group(sb, i);
3386                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3387                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3388                                  "Checksum for group %u failed (%u!=%u)",
3389                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3390                                      gdp)), le16_to_cpu(gdp->bg_checksum));
3391                         if (!sb_rdonly(sb)) {
3392                                 ext4_unlock_group(sb, i);
3393                                 return 0;
3394                         }
3395                 }
3396                 ext4_unlock_group(sb, i);
3397                 if (!flexbg_flag)
3398                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
3399         }
3400         if (NULL != first_not_zeroed)
3401                 *first_not_zeroed = grp;
3402         return 1;
3403 }
3404
3405 /*
3406  * Maximal extent format file size.
3407  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3408  * extent format containers, within a sector_t, and within i_blocks
3409  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3410  * so that won't be a limiting factor.
3411  *
3412  * However there is other limiting factor. We do store extents in the form
3413  * of starting block and length, hence the resulting length of the extent
3414  * covering maximum file size must fit into on-disk format containers as
3415  * well. Given that length is always by 1 unit bigger than max unit (because
3416  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3417  *
3418  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3419  */
3420 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3421 {
3422         loff_t res;
3423         loff_t upper_limit = MAX_LFS_FILESIZE;
3424
3425         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3426
3427         if (!has_huge_files) {
3428                 upper_limit = (1LL << 32) - 1;
3429
3430                 /* total blocks in file system block size */
3431                 upper_limit >>= (blkbits - 9);
3432                 upper_limit <<= blkbits;
3433         }
3434
3435         /*
3436          * 32-bit extent-start container, ee_block. We lower the maxbytes
3437          * by one fs block, so ee_len can cover the extent of maximum file
3438          * size
3439          */
3440         res = (1LL << 32) - 1;
3441         res <<= blkbits;
3442
3443         /* Sanity check against vm- & vfs- imposed limits */
3444         if (res > upper_limit)
3445                 res = upper_limit;
3446
3447         return res;
3448 }
3449
3450 /*
3451  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3452  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3453  * We need to be 1 filesystem block less than the 2^48 sector limit.
3454  */
3455 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3456 {
3457         loff_t upper_limit, res = EXT4_NDIR_BLOCKS;
3458         int meta_blocks;
3459         unsigned int ppb = 1 << (bits - 2);
3460
3461         /*
3462          * This is calculated to be the largest file size for a dense, block
3463          * mapped file such that the file's total number of 512-byte sectors,
3464          * including data and all indirect blocks, does not exceed (2^48 - 1).
3465          *
3466          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3467          * number of 512-byte sectors of the file.
3468          */
3469         if (!has_huge_files) {
3470                 /*
3471                  * !has_huge_files or implies that the inode i_block field
3472                  * represents total file blocks in 2^32 512-byte sectors ==
3473                  * size of vfs inode i_blocks * 8
3474                  */
3475                 upper_limit = (1LL << 32) - 1;
3476
3477                 /* total blocks in file system block size */
3478                 upper_limit >>= (bits - 9);
3479
3480         } else {
3481                 /*
3482                  * We use 48 bit ext4_inode i_blocks
3483                  * With EXT4_HUGE_FILE_FL set the i_blocks
3484                  * represent total number of blocks in
3485                  * file system block size
3486                  */
3487                 upper_limit = (1LL << 48) - 1;
3488
3489         }
3490
3491         /* Compute how many blocks we can address by block tree */
3492         res += ppb;
3493         res += ppb * ppb;
3494         res += ((loff_t)ppb) * ppb * ppb;
3495         /* Compute how many metadata blocks are needed */
3496         meta_blocks = 1;
3497         meta_blocks += 1 + ppb;
3498         meta_blocks += 1 + ppb + ppb * ppb;
3499         /* Does block tree limit file size? */
3500         if (res + meta_blocks <= upper_limit)
3501                 goto check_lfs;
3502
3503         res = upper_limit;
3504         /* How many metadata blocks are needed for addressing upper_limit? */
3505         upper_limit -= EXT4_NDIR_BLOCKS;
3506         /* indirect blocks */
3507         meta_blocks = 1;
3508         upper_limit -= ppb;
3509         /* double indirect blocks */
3510         if (upper_limit < ppb * ppb) {
3511                 meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb);
3512                 res -= meta_blocks;
3513                 goto check_lfs;
3514         }
3515         meta_blocks += 1 + ppb;
3516         upper_limit -= ppb * ppb;
3517         /* tripple indirect blocks for the rest */
3518         meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb) +
3519                 DIV_ROUND_UP_ULL(upper_limit, ppb*ppb);
3520         res -= meta_blocks;
3521 check_lfs:
3522         res <<= bits;
3523         if (res > MAX_LFS_FILESIZE)
3524                 res = MAX_LFS_FILESIZE;
3525
3526         return res;
3527 }
3528
3529 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3530                                    ext4_fsblk_t logical_sb_block, int nr)
3531 {
3532         struct ext4_sb_info *sbi = EXT4_SB(sb);
3533         ext4_group_t bg, first_meta_bg;
3534         int has_super = 0;
3535
3536         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3537
3538         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3539                 return logical_sb_block + nr + 1;
3540         bg = sbi->s_desc_per_block * nr;
3541         if (ext4_bg_has_super(sb, bg))
3542                 has_super = 1;
3543
3544         /*
3545          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3546          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3547          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3548          * compensate.
3549          */
3550         if (sb->s_blocksize == 1024 && nr == 0 &&
3551             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3552                 has_super++;
3553
3554         return (has_super + ext4_group_first_block_no(sb, bg));
3555 }
3556
3557 /**
3558  * ext4_get_stripe_size: Get the stripe size.
3559  * @sbi: In memory super block info
3560  *
3561  * If we have specified it via mount option, then
3562  * use the mount option value. If the value specified at mount time is
3563  * greater than the blocks per group use the super block value.
3564  * If the super block value is greater than blocks per group return 0.
3565  * Allocator needs it be less than blocks per group.
3566  *
3567  */
3568 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3569 {
3570         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3571         unsigned long stripe_width =
3572                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3573         int ret;
3574
3575         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3576                 ret = sbi->s_stripe;
3577         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3578                 ret = stripe_width;
3579         else if (stride && stride <= sbi->s_blocks_per_group)
3580                 ret = stride;
3581         else
3582                 ret = 0;
3583
3584         /*
3585          * If the stripe width is 1, this makes no sense and
3586          * we set it to 0 to turn off stripe handling code.
3587          */
3588         if (ret <= 1)
3589                 ret = 0;
3590
3591         return ret;
3592 }
3593
3594 /*
3595  * Check whether this filesystem can be mounted based on
3596  * the features present and the RDONLY/RDWR mount requested.
3597  * Returns 1 if this filesystem can be mounted as requested,
3598  * 0 if it cannot be.
3599  */
3600 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3601 {
3602         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3603                 ext4_msg(sb, KERN_ERR,
3604                         "Couldn't mount because of "
3605                         "unsupported optional features (%x)",
3606                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3607                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3608                 return 0;
3609         }
3610
3611 #if !IS_ENABLED(CONFIG_UNICODE)
3612         if (ext4_has_feature_casefold(sb)) {
3613                 ext4_msg(sb, KERN_ERR,
3614                          "Filesystem with casefold feature cannot be "
3615                          "mounted without CONFIG_UNICODE");
3616                 return 0;
3617         }
3618 #endif
3619
3620         if (readonly)
3621                 return 1;
3622
3623         if (ext4_has_feature_readonly(sb)) {
3624                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3625                 sb->s_flags |= SB_RDONLY;
3626                 return 1;
3627         }
3628
3629         /* Check that feature set is OK for a read-write mount */
3630         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3631                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3632                          "unsupported optional features (%x)",
3633                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3634                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3635                 return 0;
3636         }
3637         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3638                 ext4_msg(sb, KERN_ERR,
3639                          "Can't support bigalloc feature without "
3640                          "extents feature\n");
3641                 return 0;
3642         }
3643
3644 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3645         if (!readonly && (ext4_has_feature_quota(sb) ||
3646                           ext4_has_feature_project(sb))) {
3647                 ext4_msg(sb, KERN_ERR,
3648                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3649                 return 0;
3650         }
3651 #endif  /* CONFIG_QUOTA */
3652         return 1;
3653 }
3654
3655 /*
3656  * This function is called once a day if we have errors logged
3657  * on the file system
3658  */
3659 static void print_daily_error_info(struct timer_list *t)
3660 {
3661         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3662         struct super_block *sb = sbi->s_sb;
3663         struct ext4_super_block *es = sbi->s_es;
3664
3665         if (es->s_error_count)
3666                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3667                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3668                          le32_to_cpu(es->s_error_count));
3669         if (es->s_first_error_time) {
3670                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3671                        sb->s_id,
3672                        ext4_get_tstamp(es, s_first_error_time),
3673                        (int) sizeof(es->s_first_error_func),
3674                        es->s_first_error_func,
3675                        le32_to_cpu(es->s_first_error_line));
3676                 if (es->s_first_error_ino)
3677                         printk(KERN_CONT ": inode %u",
3678                                le32_to_cpu(es->s_first_error_ino));
3679                 if (es->s_first_error_block)
3680                         printk(KERN_CONT ": block %llu", (unsigned long long)
3681                                le64_to_cpu(es->s_first_error_block));
3682                 printk(KERN_CONT "\n");
3683         }
3684         if (es->s_last_error_time) {
3685                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3686                        sb->s_id,
3687                        ext4_get_tstamp(es, s_last_error_time),
3688                        (int) sizeof(es->s_last_error_func),
3689                        es->s_last_error_func,
3690                        le32_to_cpu(es->s_last_error_line));
3691                 if (es->s_last_error_ino)
3692                         printk(KERN_CONT ": inode %u",
3693                                le32_to_cpu(es->s_last_error_ino));
3694                 if (es->s_last_error_block)
3695                         printk(KERN_CONT ": block %llu", (unsigned long long)
3696                                le64_to_cpu(es->s_last_error_block));
3697                 printk(KERN_CONT "\n");
3698         }
3699         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3700 }
3701
3702 /* Find next suitable group and run ext4_init_inode_table */
3703 static int ext4_run_li_request(struct ext4_li_request *elr)
3704 {
3705         struct ext4_group_desc *gdp = NULL;
3706         struct super_block *sb = elr->lr_super;
3707         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3708         ext4_group_t group = elr->lr_next_group;
3709         unsigned int prefetch_ios = 0;
3710         int ret = 0;
3711         int nr = EXT4_SB(sb)->s_mb_prefetch;
3712         u64 start_time;
3713
3714         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3715                 elr->lr_next_group = ext4_mb_prefetch(sb, group, nr, &prefetch_ios);
3716                 ext4_mb_prefetch_fini(sb, elr->lr_next_group, nr);
3717                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group, nr);
3718                 if (group >= elr->lr_next_group) {
3719                         ret = 1;
3720                         if (elr->lr_first_not_zeroed != ngroups &&
3721                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3722                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3723                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3724                                 ret = 0;
3725                         }
3726                 }
3727                 return ret;
3728         }
3729
3730         for (; group < ngroups; group++) {
3731                 gdp = ext4_get_group_desc(sb, group, NULL);
3732                 if (!gdp) {
3733                         ret = 1;
3734                         break;
3735                 }
3736
3737                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3738                         break;
3739         }
3740
3741         if (group >= ngroups)
3742                 ret = 1;
3743
3744         if (!ret) {
3745                 start_time = ktime_get_real_ns();
3746                 ret = ext4_init_inode_table(sb, group,
3747                                             elr->lr_timeout ? 0 : 1);
3748                 trace_ext4_lazy_itable_init(sb, group);
3749                 if (elr->lr_timeout == 0) {
3750                         elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3751                                 EXT4_SB(elr->lr_super)->s_li_wait_mult);
3752                 }
3753                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3754                 elr->lr_next_group = group + 1;
3755         }
3756         return ret;
3757 }
3758
3759 /*
3760  * Remove lr_request from the list_request and free the
3761  * request structure. Should be called with li_list_mtx held
3762  */
3763 static void ext4_remove_li_request(struct ext4_li_request *elr)
3764 {
3765         if (!elr)
3766                 return;
3767
3768         list_del(&elr->lr_request);
3769         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3770         kfree(elr);
3771 }
3772
3773 static void ext4_unregister_li_request(struct super_block *sb)
3774 {
3775         mutex_lock(&ext4_li_mtx);
3776         if (!ext4_li_info) {
3777                 mutex_unlock(&ext4_li_mtx);
3778                 return;
3779         }
3780
3781         mutex_lock(&ext4_li_info->li_list_mtx);
3782         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3783         mutex_unlock(&ext4_li_info->li_list_mtx);
3784         mutex_unlock(&ext4_li_mtx);
3785 }
3786
3787 static struct task_struct *ext4_lazyinit_task;
3788
3789 /*
3790  * This is the function where ext4lazyinit thread lives. It walks
3791  * through the request list searching for next scheduled filesystem.
3792  * When such a fs is found, run the lazy initialization request
3793  * (ext4_rn_li_request) and keep track of the time spend in this
3794  * function. Based on that time we compute next schedule time of
3795  * the request. When walking through the list is complete, compute
3796  * next waking time and put itself into sleep.
3797  */
3798 static int ext4_lazyinit_thread(void *arg)
3799 {
3800         struct ext4_lazy_init *eli = arg;
3801         struct list_head *pos, *n;
3802         struct ext4_li_request *elr;
3803         unsigned long next_wakeup, cur;
3804
3805         BUG_ON(NULL == eli);
3806         set_freezable();
3807
3808 cont_thread:
3809         while (true) {
3810                 next_wakeup = MAX_JIFFY_OFFSET;
3811
3812                 mutex_lock(&eli->li_list_mtx);
3813                 if (list_empty(&eli->li_request_list)) {
3814                         mutex_unlock(&eli->li_list_mtx);
3815                         goto exit_thread;
3816                 }
3817                 list_for_each_safe(pos, n, &eli->li_request_list) {
3818                         int err = 0;
3819                         int progress = 0;
3820                         elr = list_entry(pos, struct ext4_li_request,
3821                                          lr_request);
3822
3823                         if (time_before(jiffies, elr->lr_next_sched)) {
3824                                 if (time_before(elr->lr_next_sched, next_wakeup))
3825                                         next_wakeup = elr->lr_next_sched;
3826                                 continue;
3827                         }
3828                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3829                                 if (sb_start_write_trylock(elr->lr_super)) {
3830                                         progress = 1;
3831                                         /*
3832                                          * We hold sb->s_umount, sb can not
3833                                          * be removed from the list, it is
3834                                          * now safe to drop li_list_mtx
3835                                          */
3836                                         mutex_unlock(&eli->li_list_mtx);
3837                                         err = ext4_run_li_request(elr);
3838                                         sb_end_write(elr->lr_super);
3839                                         mutex_lock(&eli->li_list_mtx);
3840                                         n = pos->next;
3841                                 }
3842                                 up_read((&elr->lr_super->s_umount));
3843                         }
3844                         /* error, remove the lazy_init job */
3845                         if (err) {
3846                                 ext4_remove_li_request(elr);
3847                                 continue;
3848                         }
3849                         if (!progress) {
3850                                 elr->lr_next_sched = jiffies +
3851                                         get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3852                         }
3853                         if (time_before(elr->lr_next_sched, next_wakeup))
3854                                 next_wakeup = elr->lr_next_sched;
3855                 }
3856                 mutex_unlock(&eli->li_list_mtx);
3857
3858                 try_to_freeze();
3859
3860                 cur = jiffies;
3861                 if ((time_after_eq(cur, next_wakeup)) ||
3862                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3863                         cond_resched();
3864                         continue;
3865                 }
3866
3867                 schedule_timeout_interruptible(next_wakeup - cur);
3868
3869                 if (kthread_should_stop()) {
3870                         ext4_clear_request_list();
3871                         goto exit_thread;
3872                 }
3873         }
3874
3875 exit_thread:
3876         /*
3877          * It looks like the request list is empty, but we need
3878          * to check it under the li_list_mtx lock, to prevent any
3879          * additions into it, and of course we should lock ext4_li_mtx
3880          * to atomically free the list and ext4_li_info, because at
3881          * this point another ext4 filesystem could be registering
3882          * new one.
3883          */
3884         mutex_lock(&ext4_li_mtx);
3885         mutex_lock(&eli->li_list_mtx);
3886         if (!list_empty(&eli->li_request_list)) {
3887                 mutex_unlock(&eli->li_list_mtx);
3888                 mutex_unlock(&ext4_li_mtx);
3889                 goto cont_thread;
3890         }
3891         mutex_unlock(&eli->li_list_mtx);
3892         kfree(ext4_li_info);
3893         ext4_li_info = NULL;
3894         mutex_unlock(&ext4_li_mtx);
3895
3896         return 0;
3897 }
3898
3899 static void ext4_clear_request_list(void)
3900 {
3901         struct list_head *pos, *n;
3902         struct ext4_li_request *elr;
3903
3904         mutex_lock(&ext4_li_info->li_list_mtx);
3905         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3906                 elr = list_entry(pos, struct ext4_li_request,
3907                                  lr_request);
3908                 ext4_remove_li_request(elr);
3909         }
3910         mutex_unlock(&ext4_li_info->li_list_mtx);
3911 }
3912
3913 static int ext4_run_lazyinit_thread(void)
3914 {
3915         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3916                                          ext4_li_info, "ext4lazyinit");
3917         if (IS_ERR(ext4_lazyinit_task)) {
3918                 int err = PTR_ERR(ext4_lazyinit_task);
3919                 ext4_clear_request_list();
3920                 kfree(ext4_li_info);
3921                 ext4_li_info = NULL;
3922                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3923                                  "initialization thread\n",
3924                                  err);
3925                 return err;
3926         }
3927         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3928         return 0;
3929 }
3930
3931 /*
3932  * Check whether it make sense to run itable init. thread or not.
3933  * If there is at least one uninitialized inode table, return
3934  * corresponding group number, else the loop goes through all
3935  * groups and return total number of groups.
3936  */
3937 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3938 {
3939         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3940         struct ext4_group_desc *gdp = NULL;
3941
3942         if (!ext4_has_group_desc_csum(sb))
3943                 return ngroups;
3944
3945         for (group = 0; group < ngroups; group++) {
3946                 gdp = ext4_get_group_desc(sb, group, NULL);
3947                 if (!gdp)
3948                         continue;
3949
3950                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3951                         break;
3952         }
3953
3954         return group;
3955 }
3956
3957 static int ext4_li_info_new(void)
3958 {
3959         struct ext4_lazy_init *eli = NULL;
3960
3961         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3962         if (!eli)
3963                 return -ENOMEM;
3964
3965         INIT_LIST_HEAD(&eli->li_request_list);
3966         mutex_init(&eli->li_list_mtx);
3967
3968         eli->li_state |= EXT4_LAZYINIT_QUIT;
3969
3970         ext4_li_info = eli;
3971
3972         return 0;
3973 }
3974
3975 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3976                                             ext4_group_t start)
3977 {
3978         struct ext4_li_request *elr;
3979
3980         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3981         if (!elr)
3982                 return NULL;
3983
3984         elr->lr_super = sb;
3985         elr->lr_first_not_zeroed = start;
3986         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3987                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3988                 elr->lr_next_group = start;
3989         } else {
3990                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3991         }
3992
3993         /*
3994          * Randomize first schedule time of the request to
3995          * spread the inode table initialization requests
3996          * better.
3997          */
3998         elr->lr_next_sched = jiffies + get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3999         return elr;
4000 }
4001
4002 int ext4_register_li_request(struct super_block *sb,
4003                              ext4_group_t first_not_zeroed)
4004 {
4005         struct ext4_sb_info *sbi = EXT4_SB(sb);
4006         struct ext4_li_request *elr = NULL;
4007         ext4_group_t ngroups = sbi->s_groups_count;
4008         int ret = 0;
4009
4010         mutex_lock(&ext4_li_mtx);
4011         if (sbi->s_li_request != NULL) {
4012                 /*
4013                  * Reset timeout so it can be computed again, because
4014                  * s_li_wait_mult might have changed.
4015                  */
4016                 sbi->s_li_request->lr_timeout = 0;
4017                 goto out;
4018         }
4019
4020         if (sb_rdonly(sb) ||
4021             (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
4022              (first_not_zeroed == ngroups || !test_opt(sb, INIT_INODE_TABLE))))
4023                 goto out;
4024
4025         elr = ext4_li_request_new(sb, first_not_zeroed);
4026         if (!elr) {
4027                 ret = -ENOMEM;
4028                 goto out;
4029         }
4030
4031         if (NULL == ext4_li_info) {
4032                 ret = ext4_li_info_new();
4033                 if (ret)
4034                         goto out;
4035         }
4036
4037         mutex_lock(&ext4_li_info->li_list_mtx);
4038         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
4039         mutex_unlock(&ext4_li_info->li_list_mtx);
4040
4041         sbi->s_li_request = elr;
4042         /*
4043          * set elr to NULL here since it has been inserted to
4044          * the request_list and the removal and free of it is
4045          * handled by ext4_clear_request_list from now on.
4046          */
4047         elr = NULL;
4048
4049         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
4050                 ret = ext4_run_lazyinit_thread();
4051                 if (ret)
4052                         goto out;
4053         }
4054 out:
4055         mutex_unlock(&ext4_li_mtx);
4056         if (ret)
4057                 kfree(elr);
4058         return ret;
4059 }
4060
4061 /*
4062  * We do not need to lock anything since this is called on
4063  * module unload.
4064  */
4065 static void ext4_destroy_lazyinit_thread(void)
4066 {
4067         /*
4068          * If thread exited earlier
4069          * there's nothing to be done.
4070          */
4071         if (!ext4_li_info || !ext4_lazyinit_task)
4072                 return;
4073
4074         kthread_stop(ext4_lazyinit_task);
4075 }
4076
4077 static int set_journal_csum_feature_set(struct super_block *sb)
4078 {
4079         int ret = 1;
4080         int compat, incompat;
4081         struct ext4_sb_info *sbi = EXT4_SB(sb);
4082
4083         if (ext4_has_metadata_csum(sb)) {
4084                 /* journal checksum v3 */
4085                 compat = 0;
4086                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4087         } else {
4088                 /* journal checksum v1 */
4089                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4090                 incompat = 0;
4091         }
4092
4093         jbd2_journal_clear_features(sbi->s_journal,
4094                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4095                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4096                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
4097         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4098                 ret = jbd2_journal_set_features(sbi->s_journal,
4099                                 compat, 0,
4100                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4101                                 incompat);
4102         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4103                 ret = jbd2_journal_set_features(sbi->s_journal,
4104                                 compat, 0,
4105                                 incompat);
4106                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4107                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4108         } else {
4109                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4110                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4111         }
4112
4113         return ret;
4114 }
4115
4116 /*
4117  * Note: calculating the overhead so we can be compatible with
4118  * historical BSD practice is quite difficult in the face of
4119  * clusters/bigalloc.  This is because multiple metadata blocks from
4120  * different block group can end up in the same allocation cluster.
4121  * Calculating the exact overhead in the face of clustered allocation
4122  * requires either O(all block bitmaps) in memory or O(number of block
4123  * groups**2) in time.  We will still calculate the superblock for
4124  * older file systems --- and if we come across with a bigalloc file
4125  * system with zero in s_overhead_clusters the estimate will be close to
4126  * correct especially for very large cluster sizes --- but for newer
4127  * file systems, it's better to calculate this figure once at mkfs
4128  * time, and store it in the superblock.  If the superblock value is
4129  * present (even for non-bigalloc file systems), we will use it.
4130  */
4131 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4132                           char *buf)
4133 {
4134         struct ext4_sb_info     *sbi = EXT4_SB(sb);
4135         struct ext4_group_desc  *gdp;
4136         ext4_fsblk_t            first_block, last_block, b;
4137         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
4138         int                     s, j, count = 0;
4139         int                     has_super = ext4_bg_has_super(sb, grp);
4140
4141         if (!ext4_has_feature_bigalloc(sb))
4142                 return (has_super + ext4_bg_num_gdb(sb, grp) +
4143                         (has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
4144                         sbi->s_itb_per_group + 2);
4145
4146         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4147                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
4148         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4149         for (i = 0; i < ngroups; i++) {
4150                 gdp = ext4_get_group_desc(sb, i, NULL);
4151                 b = ext4_block_bitmap(sb, gdp);
4152                 if (b >= first_block && b <= last_block) {
4153                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4154                         count++;
4155                 }
4156                 b = ext4_inode_bitmap(sb, gdp);
4157                 if (b >= first_block && b <= last_block) {
4158                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4159                         count++;
4160                 }
4161                 b = ext4_inode_table(sb, gdp);
4162                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4163                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4164                                 int c = EXT4_B2C(sbi, b - first_block);
4165                                 ext4_set_bit(c, buf);
4166                                 count++;
4167                         }
4168                 if (i != grp)
4169                         continue;
4170                 s = 0;
4171                 if (ext4_bg_has_super(sb, grp)) {
4172                         ext4_set_bit(s++, buf);
4173                         count++;
4174                 }
4175                 j = ext4_bg_num_gdb(sb, grp);
4176                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4177                         ext4_error(sb, "Invalid number of block group "
4178                                    "descriptor blocks: %d", j);
4179                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4180                 }
4181                 count += j;
4182                 for (; j > 0; j--)
4183                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4184         }
4185         if (!count)
4186                 return 0;
4187         return EXT4_CLUSTERS_PER_GROUP(sb) -
4188                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4189 }
4190
4191 /*
4192  * Compute the overhead and stash it in sbi->s_overhead
4193  */
4194 int ext4_calculate_overhead(struct super_block *sb)
4195 {
4196         struct ext4_sb_info *sbi = EXT4_SB(sb);
4197         struct ext4_super_block *es = sbi->s_es;
4198         struct inode *j_inode;
4199         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4200         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4201         ext4_fsblk_t overhead = 0;
4202         char *buf = (char *) get_zeroed_page(GFP_NOFS);
4203
4204         if (!buf)
4205                 return -ENOMEM;
4206
4207         /*
4208          * Compute the overhead (FS structures).  This is constant
4209          * for a given filesystem unless the number of block groups
4210          * changes so we cache the previous value until it does.
4211          */
4212
4213         /*
4214          * All of the blocks before first_data_block are overhead
4215          */
4216         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4217
4218         /*
4219          * Add the overhead found in each block group
4220          */
4221         for (i = 0; i < ngroups; i++) {
4222                 int blks;
4223
4224                 blks = count_overhead(sb, i, buf);
4225                 overhead += blks;
4226                 if (blks)
4227                         memset(buf, 0, PAGE_SIZE);
4228                 cond_resched();
4229         }
4230
4231         /*
4232          * Add the internal journal blocks whether the journal has been
4233          * loaded or not
4234          */
4235         if (sbi->s_journal && !sbi->s_journal_bdev_file)
4236                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4237         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4238                 /* j_inum for internal journal is non-zero */
4239                 j_inode = ext4_get_journal_inode(sb, j_inum);
4240                 if (!IS_ERR(j_inode)) {
4241                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4242                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
4243                         iput(j_inode);
4244                 } else {
4245                         ext4_msg(sb, KERN_ERR, "can't get journal size");
4246                 }
4247         }
4248         sbi->s_overhead = overhead;
4249         smp_wmb();
4250         free_page((unsigned long) buf);
4251         return 0;
4252 }
4253
4254 static void ext4_set_resv_clusters(struct super_block *sb)
4255 {
4256         ext4_fsblk_t resv_clusters;
4257         struct ext4_sb_info *sbi = EXT4_SB(sb);
4258
4259         /*
4260          * There's no need to reserve anything when we aren't using extents.
4261          * The space estimates are exact, there are no unwritten extents,
4262          * hole punching doesn't need new metadata... This is needed especially
4263          * to keep ext2/3 backward compatibility.
4264          */
4265         if (!ext4_has_feature_extents(sb))
4266                 return;
4267         /*
4268          * By default we reserve 2% or 4096 clusters, whichever is smaller.
4269          * This should cover the situations where we can not afford to run
4270          * out of space like for example punch hole, or converting
4271          * unwritten extents in delalloc path. In most cases such
4272          * allocation would require 1, or 2 blocks, higher numbers are
4273          * very rare.
4274          */
4275         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4276                          sbi->s_cluster_bits);
4277
4278         do_div(resv_clusters, 50);
4279         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4280
4281         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4282 }
4283
4284 static const char *ext4_quota_mode(struct super_block *sb)
4285 {
4286 #ifdef CONFIG_QUOTA
4287         if (!ext4_quota_capable(sb))
4288                 return "none";
4289
4290         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4291                 return "journalled";
4292         else
4293                 return "writeback";
4294 #else
4295         return "disabled";
4296 #endif
4297 }
4298
4299 static void ext4_setup_csum_trigger(struct super_block *sb,
4300                                     enum ext4_journal_trigger_type type,
4301                                     void (*trigger)(
4302                                         struct jbd2_buffer_trigger_type *type,
4303                                         struct buffer_head *bh,
4304                                         void *mapped_data,
4305                                         size_t size))
4306 {
4307         struct ext4_sb_info *sbi = EXT4_SB(sb);
4308
4309         sbi->s_journal_triggers[type].sb = sb;
4310         sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4311 }
4312
4313 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4314 {
4315         if (!sbi)
4316                 return;
4317
4318         kfree(sbi->s_blockgroup_lock);
4319         fs_put_dax(sbi->s_daxdev, NULL);
4320         kfree(sbi);
4321 }
4322
4323 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4324 {
4325         struct ext4_sb_info *sbi;
4326
4327         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4328         if (!sbi)
4329                 return NULL;
4330
4331         sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
4332                                            NULL, NULL);
4333
4334         sbi->s_blockgroup_lock =
4335                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4336
4337         if (!sbi->s_blockgroup_lock)
4338                 goto err_out;
4339
4340         sb->s_fs_info = sbi;
4341         sbi->s_sb = sb;
4342         return sbi;
4343 err_out:
4344         fs_put_dax(sbi->s_daxdev, NULL);
4345         kfree(sbi);
4346         return NULL;
4347 }
4348
4349 static void ext4_set_def_opts(struct super_block *sb,
4350                               struct ext4_super_block *es)
4351 {
4352         unsigned long def_mount_opts;
4353
4354         /* Set defaults before we parse the mount options */
4355         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4356         set_opt(sb, INIT_INODE_TABLE);
4357         if (def_mount_opts & EXT4_DEFM_DEBUG)
4358                 set_opt(sb, DEBUG);
4359         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4360                 set_opt(sb, GRPID);
4361         if (def_mount_opts & EXT4_DEFM_UID16)
4362                 set_opt(sb, NO_UID32);
4363         /* xattr user namespace & acls are now defaulted on */
4364         set_opt(sb, XATTR_USER);
4365 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4366         set_opt(sb, POSIX_ACL);
4367 #endif
4368         if (ext4_has_feature_fast_commit(sb))
4369                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4370         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4371         if (ext4_has_metadata_csum(sb))
4372                 set_opt(sb, JOURNAL_CHECKSUM);
4373
4374         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4375                 set_opt(sb, JOURNAL_DATA);
4376         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4377                 set_opt(sb, ORDERED_DATA);
4378         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4379                 set_opt(sb, WRITEBACK_DATA);
4380
4381         if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_PANIC)
4382                 set_opt(sb, ERRORS_PANIC);
4383         else if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_CONTINUE)
4384                 set_opt(sb, ERRORS_CONT);
4385         else
4386                 set_opt(sb, ERRORS_RO);
4387         /* block_validity enabled by default; disable with noblock_validity */
4388         set_opt(sb, BLOCK_VALIDITY);
4389         if (def_mount_opts & EXT4_DEFM_DISCARD)
4390                 set_opt(sb, DISCARD);
4391
4392         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4393                 set_opt(sb, BARRIER);
4394
4395         /*
4396          * enable delayed allocation by default
4397          * Use -o nodelalloc to turn it off
4398          */
4399         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4400             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4401                 set_opt(sb, DELALLOC);
4402
4403         if (sb->s_blocksize <= PAGE_SIZE)
4404                 set_opt(sb, DIOREAD_NOLOCK);
4405 }
4406
4407 static int ext4_handle_clustersize(struct super_block *sb)
4408 {
4409         struct ext4_sb_info *sbi = EXT4_SB(sb);
4410         struct ext4_super_block *es = sbi->s_es;
4411         int clustersize;
4412
4413         /* Handle clustersize */
4414         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4415         if (ext4_has_feature_bigalloc(sb)) {
4416                 if (clustersize < sb->s_blocksize) {
4417                         ext4_msg(sb, KERN_ERR,
4418                                  "cluster size (%d) smaller than "
4419                                  "block size (%lu)", clustersize, sb->s_blocksize);
4420                         return -EINVAL;
4421                 }
4422                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4423                         le32_to_cpu(es->s_log_block_size);
4424         } else {
4425                 if (clustersize != sb->s_blocksize) {
4426                         ext4_msg(sb, KERN_ERR,
4427                                  "fragment/cluster size (%d) != "
4428                                  "block size (%lu)", clustersize, sb->s_blocksize);
4429                         return -EINVAL;
4430                 }
4431                 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
4432                         ext4_msg(sb, KERN_ERR,
4433                                  "#blocks per group too big: %lu",
4434                                  sbi->s_blocks_per_group);
4435                         return -EINVAL;
4436                 }
4437                 sbi->s_cluster_bits = 0;
4438         }
4439         sbi->s_clusters_per_group = le32_to_cpu(es->s_clusters_per_group);
4440         if (sbi->s_clusters_per_group > sb->s_blocksize * 8) {
4441                 ext4_msg(sb, KERN_ERR, "#clusters per group too big: %lu",
4442                          sbi->s_clusters_per_group);
4443                 return -EINVAL;
4444         }
4445         if (sbi->s_blocks_per_group !=
4446             (sbi->s_clusters_per_group * (clustersize / sb->s_blocksize))) {
4447                 ext4_msg(sb, KERN_ERR,
4448                          "blocks per group (%lu) and clusters per group (%lu) inconsistent",
4449                          sbi->s_blocks_per_group, sbi->s_clusters_per_group);
4450                 return -EINVAL;
4451         }
4452         sbi->s_cluster_ratio = clustersize / sb->s_blocksize;
4453
4454         /* Do we have standard group size of clustersize * 8 blocks ? */
4455         if (sbi->s_blocks_per_group == clustersize << 3)
4456                 set_opt2(sb, STD_GROUP_SIZE);
4457
4458         return 0;
4459 }
4460
4461 static void ext4_fast_commit_init(struct super_block *sb)
4462 {
4463         struct ext4_sb_info *sbi = EXT4_SB(sb);
4464
4465         /* Initialize fast commit stuff */
4466         atomic_set(&sbi->s_fc_subtid, 0);
4467         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4468         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4469         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4470         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4471         sbi->s_fc_bytes = 0;
4472         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4473         sbi->s_fc_ineligible_tid = 0;
4474         spin_lock_init(&sbi->s_fc_lock);
4475         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4476         sbi->s_fc_replay_state.fc_regions = NULL;
4477         sbi->s_fc_replay_state.fc_regions_size = 0;
4478         sbi->s_fc_replay_state.fc_regions_used = 0;
4479         sbi->s_fc_replay_state.fc_regions_valid = 0;
4480         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4481         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4482         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4483 }
4484
4485 static int ext4_inode_info_init(struct super_block *sb,
4486                                 struct ext4_super_block *es)
4487 {
4488         struct ext4_sb_info *sbi = EXT4_SB(sb);
4489
4490         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4491                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4492                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4493         } else {
4494                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4495                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4496                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4497                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4498                                  sbi->s_first_ino);
4499                         return -EINVAL;
4500                 }
4501                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4502                     (!is_power_of_2(sbi->s_inode_size)) ||
4503                     (sbi->s_inode_size > sb->s_blocksize)) {
4504                         ext4_msg(sb, KERN_ERR,
4505                                "unsupported inode size: %d",
4506                                sbi->s_inode_size);
4507                         ext4_msg(sb, KERN_ERR, "blocksize: %lu", sb->s_blocksize);
4508                         return -EINVAL;
4509                 }
4510                 /*
4511                  * i_atime_extra is the last extra field available for
4512                  * [acm]times in struct ext4_inode. Checking for that
4513                  * field should suffice to ensure we have extra space
4514                  * for all three.
4515                  */
4516                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4517                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4518                         sb->s_time_gran = 1;
4519                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4520                 } else {
4521                         sb->s_time_gran = NSEC_PER_SEC;
4522                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4523                 }
4524                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4525         }
4526
4527         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4528                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4529                         EXT4_GOOD_OLD_INODE_SIZE;
4530                 if (ext4_has_feature_extra_isize(sb)) {
4531                         unsigned v, max = (sbi->s_inode_size -
4532                                            EXT4_GOOD_OLD_INODE_SIZE);
4533
4534                         v = le16_to_cpu(es->s_want_extra_isize);
4535                         if (v > max) {
4536                                 ext4_msg(sb, KERN_ERR,
4537                                          "bad s_want_extra_isize: %d", v);
4538                                 return -EINVAL;
4539                         }
4540                         if (sbi->s_want_extra_isize < v)
4541                                 sbi->s_want_extra_isize = v;
4542
4543                         v = le16_to_cpu(es->s_min_extra_isize);
4544                         if (v > max) {
4545                                 ext4_msg(sb, KERN_ERR,
4546                                          "bad s_min_extra_isize: %d", v);
4547                                 return -EINVAL;
4548                         }
4549                         if (sbi->s_want_extra_isize < v)
4550                                 sbi->s_want_extra_isize = v;
4551                 }
4552         }
4553
4554         return 0;
4555 }
4556
4557 #if IS_ENABLED(CONFIG_UNICODE)
4558 static int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4559 {
4560         const struct ext4_sb_encodings *encoding_info;
4561         struct unicode_map *encoding;
4562         __u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4563
4564         if (!ext4_has_feature_casefold(sb) || sb->s_encoding)
4565                 return 0;
4566
4567         encoding_info = ext4_sb_read_encoding(es);
4568         if (!encoding_info) {
4569                 ext4_msg(sb, KERN_ERR,
4570                         "Encoding requested by superblock is unknown");
4571                 return -EINVAL;
4572         }
4573
4574         encoding = utf8_load(encoding_info->version);
4575         if (IS_ERR(encoding)) {
4576                 ext4_msg(sb, KERN_ERR,
4577                         "can't mount with superblock charset: %s-%u.%u.%u "
4578                         "not supported by the kernel. flags: 0x%x.",
4579                         encoding_info->name,
4580                         unicode_major(encoding_info->version),
4581                         unicode_minor(encoding_info->version),
4582                         unicode_rev(encoding_info->version),
4583                         encoding_flags);
4584                 return -EINVAL;
4585         }
4586         ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4587                 "%s-%u.%u.%u with flags 0x%hx", encoding_info->name,
4588                 unicode_major(encoding_info->version),
4589                 unicode_minor(encoding_info->version),
4590                 unicode_rev(encoding_info->version),
4591                 encoding_flags);
4592
4593         sb->s_encoding = encoding;
4594         sb->s_encoding_flags = encoding_flags;
4595
4596         return 0;
4597 }
4598 #else
4599 static inline int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4600 {
4601         return 0;
4602 }
4603 #endif
4604
4605 static int ext4_init_metadata_csum(struct super_block *sb, struct ext4_super_block *es)
4606 {
4607         struct ext4_sb_info *sbi = EXT4_SB(sb);
4608
4609         /* Warn if metadata_csum and gdt_csum are both set. */
4610         if (ext4_has_feature_metadata_csum(sb) &&
4611             ext4_has_feature_gdt_csum(sb))
4612                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4613                              "redundant flags; please run fsck.");
4614
4615         /* Check for a known checksum algorithm */
4616         if (!ext4_verify_csum_type(sb, es)) {
4617                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4618                          "unknown checksum algorithm.");
4619                 return -EINVAL;
4620         }
4621         ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4622                                 ext4_orphan_file_block_trigger);
4623
4624         /* Load the checksum driver */
4625         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4626         if (IS_ERR(sbi->s_chksum_driver)) {
4627                 int ret = PTR_ERR(sbi->s_chksum_driver);
4628                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4629                 sbi->s_chksum_driver = NULL;
4630                 return ret;
4631         }
4632
4633         /* Check superblock checksum */
4634         if (!ext4_superblock_csum_verify(sb, es)) {
4635                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4636                          "invalid superblock checksum.  Run e2fsck?");
4637                 return -EFSBADCRC;
4638         }
4639
4640         /* Precompute checksum seed for all metadata */
4641         if (ext4_has_feature_csum_seed(sb))
4642                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4643         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4644                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4645                                                sizeof(es->s_uuid));
4646         return 0;
4647 }
4648
4649 static int ext4_check_feature_compatibility(struct super_block *sb,
4650                                             struct ext4_super_block *es,
4651                                             int silent)
4652 {
4653         struct ext4_sb_info *sbi = EXT4_SB(sb);
4654
4655         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4656             (ext4_has_compat_features(sb) ||
4657              ext4_has_ro_compat_features(sb) ||
4658              ext4_has_incompat_features(sb)))
4659                 ext4_msg(sb, KERN_WARNING,
4660                        "feature flags set on rev 0 fs, "
4661                        "running e2fsck is recommended");
4662
4663         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4664                 set_opt2(sb, HURD_COMPAT);
4665                 if (ext4_has_feature_64bit(sb)) {
4666                         ext4_msg(sb, KERN_ERR,
4667                                  "The Hurd can't support 64-bit file systems");
4668                         return -EINVAL;
4669                 }
4670
4671                 /*
4672                  * ea_inode feature uses l_i_version field which is not
4673                  * available in HURD_COMPAT mode.
4674                  */
4675                 if (ext4_has_feature_ea_inode(sb)) {
4676                         ext4_msg(sb, KERN_ERR,
4677                                  "ea_inode feature is not supported for Hurd");
4678                         return -EINVAL;
4679                 }
4680         }
4681
4682         if (IS_EXT2_SB(sb)) {
4683                 if (ext2_feature_set_ok(sb))
4684                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4685                                  "using the ext4 subsystem");
4686                 else {
4687                         /*
4688                          * If we're probing be silent, if this looks like
4689                          * it's actually an ext[34] filesystem.
4690                          */
4691                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4692                                 return -EINVAL;
4693                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4694                                  "to feature incompatibilities");
4695                         return -EINVAL;
4696                 }
4697         }
4698
4699         if (IS_EXT3_SB(sb)) {
4700                 if (ext3_feature_set_ok(sb))
4701                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4702                                  "using the ext4 subsystem");
4703                 else {
4704                         /*
4705                          * If we're probing be silent, if this looks like
4706                          * it's actually an ext4 filesystem.
4707                          */
4708                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4709                                 return -EINVAL;
4710                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4711                                  "to feature incompatibilities");
4712                         return -EINVAL;
4713                 }
4714         }
4715
4716         /*
4717          * Check feature flags regardless of the revision level, since we
4718          * previously didn't change the revision level when setting the flags,
4719          * so there is a chance incompat flags are set on a rev 0 filesystem.
4720          */
4721         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4722                 return -EINVAL;
4723
4724         if (sbi->s_daxdev) {
4725                 if (sb->s_blocksize == PAGE_SIZE)
4726                         set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4727                 else
4728                         ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
4729         }
4730
4731         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4732                 if (ext4_has_feature_inline_data(sb)) {
4733                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4734                                         " that may contain inline data");
4735                         return -EINVAL;
4736                 }
4737                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4738                         ext4_msg(sb, KERN_ERR,
4739                                 "DAX unsupported by block device.");
4740                         return -EINVAL;
4741                 }
4742         }
4743
4744         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4745                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4746                          es->s_encryption_level);
4747                 return -EINVAL;
4748         }
4749
4750         return 0;
4751 }
4752
4753 static int ext4_check_geometry(struct super_block *sb,
4754                                struct ext4_super_block *es)
4755 {
4756         struct ext4_sb_info *sbi = EXT4_SB(sb);
4757         __u64 blocks_count;
4758         int err;
4759
4760         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (sb->s_blocksize / 4)) {
4761                 ext4_msg(sb, KERN_ERR,
4762                          "Number of reserved GDT blocks insanely large: %d",
4763                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4764                 return -EINVAL;
4765         }
4766         /*
4767          * Test whether we have more sectors than will fit in sector_t,
4768          * and whether the max offset is addressable by the page cache.
4769          */
4770         err = generic_check_addressable(sb->s_blocksize_bits,
4771                                         ext4_blocks_count(es));
4772         if (err) {
4773                 ext4_msg(sb, KERN_ERR, "filesystem"
4774                          " too large to mount safely on this system");
4775                 return err;
4776         }
4777
4778         /* check blocks count against device size */
4779         blocks_count = sb_bdev_nr_blocks(sb);
4780         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4781                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4782                        "exceeds size of device (%llu blocks)",
4783                        ext4_blocks_count(es), blocks_count);
4784                 return -EINVAL;
4785         }
4786
4787         /*
4788          * It makes no sense for the first data block to be beyond the end
4789          * of the filesystem.
4790          */
4791         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4792                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4793                          "block %u is beyond end of filesystem (%llu)",
4794                          le32_to_cpu(es->s_first_data_block),
4795                          ext4_blocks_count(es));
4796                 return -EINVAL;
4797         }
4798         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4799             (sbi->s_cluster_ratio == 1)) {
4800                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4801                          "block is 0 with a 1k block and cluster size");
4802                 return -EINVAL;
4803         }
4804
4805         blocks_count = (ext4_blocks_count(es) -
4806                         le32_to_cpu(es->s_first_data_block) +
4807                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4808         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4809         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4810                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4811                        "(block count %llu, first data block %u, "
4812                        "blocks per group %lu)", blocks_count,
4813                        ext4_blocks_count(es),
4814                        le32_to_cpu(es->s_first_data_block),
4815                        EXT4_BLOCKS_PER_GROUP(sb));
4816                 return -EINVAL;
4817         }
4818         sbi->s_groups_count = blocks_count;
4819         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4820                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4821         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4822             le32_to_cpu(es->s_inodes_count)) {
4823                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4824                          le32_to_cpu(es->s_inodes_count),
4825                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4826                 return -EINVAL;
4827         }
4828
4829         return 0;
4830 }
4831
4832 static int ext4_group_desc_init(struct super_block *sb,
4833                                 struct ext4_super_block *es,
4834                                 ext4_fsblk_t logical_sb_block,
4835                                 ext4_group_t *first_not_zeroed)
4836 {
4837         struct ext4_sb_info *sbi = EXT4_SB(sb);
4838         unsigned int db_count;
4839         ext4_fsblk_t block;
4840         int i;
4841
4842         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4843                    EXT4_DESC_PER_BLOCK(sb);
4844         if (ext4_has_feature_meta_bg(sb)) {
4845                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4846                         ext4_msg(sb, KERN_WARNING,
4847                                  "first meta block group too large: %u "
4848                                  "(group descriptor block count %u)",
4849                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4850                         return -EINVAL;
4851                 }
4852         }
4853         rcu_assign_pointer(sbi->s_group_desc,
4854                            kvmalloc_array(db_count,
4855                                           sizeof(struct buffer_head *),
4856                                           GFP_KERNEL));
4857         if (sbi->s_group_desc == NULL) {
4858                 ext4_msg(sb, KERN_ERR, "not enough memory");
4859                 return -ENOMEM;
4860         }
4861
4862         bgl_lock_init(sbi->s_blockgroup_lock);
4863
4864         /* Pre-read the descriptors into the buffer cache */
4865         for (i = 0; i < db_count; i++) {
4866                 block = descriptor_loc(sb, logical_sb_block, i);
4867                 ext4_sb_breadahead_unmovable(sb, block);
4868         }
4869
4870         for (i = 0; i < db_count; i++) {
4871                 struct buffer_head *bh;
4872
4873                 block = descriptor_loc(sb, logical_sb_block, i);
4874                 bh = ext4_sb_bread_unmovable(sb, block);
4875                 if (IS_ERR(bh)) {
4876                         ext4_msg(sb, KERN_ERR,
4877                                "can't read group descriptor %d", i);
4878                         sbi->s_gdb_count = i;
4879                         return PTR_ERR(bh);
4880                 }
4881                 rcu_read_lock();
4882                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4883                 rcu_read_unlock();
4884         }
4885         sbi->s_gdb_count = db_count;
4886         if (!ext4_check_descriptors(sb, logical_sb_block, first_not_zeroed)) {
4887                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4888                 return -EFSCORRUPTED;
4889         }
4890
4891         return 0;
4892 }
4893
4894 static int ext4_load_and_init_journal(struct super_block *sb,
4895                                       struct ext4_super_block *es,
4896                                       struct ext4_fs_context *ctx)
4897 {
4898         struct ext4_sb_info *sbi = EXT4_SB(sb);
4899         int err;
4900
4901         err = ext4_load_journal(sb, es, ctx->journal_devnum);
4902         if (err)
4903                 return err;
4904
4905         if (ext4_has_feature_64bit(sb) &&
4906             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4907                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4908                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4909                 goto out;
4910         }
4911
4912         if (!set_journal_csum_feature_set(sb)) {
4913                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4914                          "feature set");
4915                 goto out;
4916         }
4917
4918         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4919                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4920                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4921                 ext4_msg(sb, KERN_ERR,
4922                         "Failed to set fast commit journal feature");
4923                 goto out;
4924         }
4925
4926         /* We have now updated the journal if required, so we can
4927          * validate the data journaling mode. */
4928         switch (test_opt(sb, DATA_FLAGS)) {
4929         case 0:
4930                 /* No mode set, assume a default based on the journal
4931                  * capabilities: ORDERED_DATA if the journal can
4932                  * cope, else JOURNAL_DATA
4933                  */
4934                 if (jbd2_journal_check_available_features
4935                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4936                         set_opt(sb, ORDERED_DATA);
4937                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4938                 } else {
4939                         set_opt(sb, JOURNAL_DATA);
4940                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4941                 }
4942                 break;
4943
4944         case EXT4_MOUNT_ORDERED_DATA:
4945         case EXT4_MOUNT_WRITEBACK_DATA:
4946                 if (!jbd2_journal_check_available_features
4947                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4948                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4949                                "requested data journaling mode");
4950                         goto out;
4951                 }
4952                 break;
4953         default:
4954                 break;
4955         }
4956
4957         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4958             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4959                 ext4_msg(sb, KERN_ERR, "can't mount with "
4960                         "journal_async_commit in data=ordered mode");
4961                 goto out;
4962         }
4963
4964         set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
4965
4966         sbi->s_journal->j_submit_inode_data_buffers =
4967                 ext4_journal_submit_inode_data_buffers;
4968         sbi->s_journal->j_finish_inode_data_buffers =
4969                 ext4_journal_finish_inode_data_buffers;
4970
4971         return 0;
4972
4973 out:
4974         /* flush s_sb_upd_work before destroying the journal. */
4975         flush_work(&sbi->s_sb_upd_work);
4976         jbd2_journal_destroy(sbi->s_journal);
4977         sbi->s_journal = NULL;
4978         return -EINVAL;
4979 }
4980
4981 static int ext4_check_journal_data_mode(struct super_block *sb)
4982 {
4983         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4984                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with "
4985                             "data=journal disables delayed allocation, "
4986                             "dioread_nolock, O_DIRECT and fast_commit support!\n");
4987                 /* can't mount with both data=journal and dioread_nolock. */
4988                 clear_opt(sb, DIOREAD_NOLOCK);
4989                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4990                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4991                         ext4_msg(sb, KERN_ERR, "can't mount with "
4992                                  "both data=journal and delalloc");
4993                         return -EINVAL;
4994                 }
4995                 if (test_opt(sb, DAX_ALWAYS)) {
4996                         ext4_msg(sb, KERN_ERR, "can't mount with "
4997                                  "both data=journal and dax");
4998                         return -EINVAL;
4999                 }
5000                 if (ext4_has_feature_encrypt(sb)) {
5001                         ext4_msg(sb, KERN_WARNING,
5002                                  "encrypted files will use data=ordered "
5003                                  "instead of data journaling mode");
5004                 }
5005                 if (test_opt(sb, DELALLOC))
5006                         clear_opt(sb, DELALLOC);
5007         } else {
5008                 sb->s_iflags |= SB_I_CGROUPWB;
5009         }
5010
5011         return 0;
5012 }
5013
5014 static int ext4_load_super(struct super_block *sb, ext4_fsblk_t *lsb,
5015                            int silent)
5016 {
5017         struct ext4_sb_info *sbi = EXT4_SB(sb);
5018         struct ext4_super_block *es;
5019         ext4_fsblk_t logical_sb_block;
5020         unsigned long offset = 0;
5021         struct buffer_head *bh;
5022         int ret = -EINVAL;
5023         int blocksize;
5024
5025         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
5026         if (!blocksize) {
5027                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
5028                 return -EINVAL;
5029         }
5030
5031         /*
5032          * The ext4 superblock will not be buffer aligned for other than 1kB
5033          * block sizes.  We need to calculate the offset from buffer start.
5034          */
5035         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
5036                 logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5037                 offset = do_div(logical_sb_block, blocksize);
5038         } else {
5039                 logical_sb_block = sbi->s_sb_block;
5040         }
5041
5042         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5043         if (IS_ERR(bh)) {
5044                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
5045                 return PTR_ERR(bh);
5046         }
5047         /*
5048          * Note: s_es must be initialized as soon as possible because
5049          *       some ext4 macro-instructions depend on its value
5050          */
5051         es = (struct ext4_super_block *) (bh->b_data + offset);
5052         sbi->s_es = es;
5053         sb->s_magic = le16_to_cpu(es->s_magic);
5054         if (sb->s_magic != EXT4_SUPER_MAGIC) {
5055                 if (!silent)
5056                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5057                 goto out;
5058         }
5059
5060         if (le32_to_cpu(es->s_log_block_size) >
5061             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5062                 ext4_msg(sb, KERN_ERR,
5063                          "Invalid log block size: %u",
5064                          le32_to_cpu(es->s_log_block_size));
5065                 goto out;
5066         }
5067         if (le32_to_cpu(es->s_log_cluster_size) >
5068             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5069                 ext4_msg(sb, KERN_ERR,
5070                          "Invalid log cluster size: %u",
5071                          le32_to_cpu(es->s_log_cluster_size));
5072                 goto out;
5073         }
5074
5075         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
5076
5077         /*
5078          * If the default block size is not the same as the real block size,
5079          * we need to reload it.
5080          */
5081         if (sb->s_blocksize == blocksize) {
5082                 *lsb = logical_sb_block;
5083                 sbi->s_sbh = bh;
5084                 return 0;
5085         }
5086
5087         /*
5088          * bh must be released before kill_bdev(), otherwise
5089          * it won't be freed and its page also. kill_bdev()
5090          * is called by sb_set_blocksize().
5091          */
5092         brelse(bh);
5093         /* Validate the filesystem blocksize */
5094         if (!sb_set_blocksize(sb, blocksize)) {
5095                 ext4_msg(sb, KERN_ERR, "bad block size %d",
5096                                 blocksize);
5097                 bh = NULL;
5098                 goto out;
5099         }
5100
5101         logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5102         offset = do_div(logical_sb_block, blocksize);
5103         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5104         if (IS_ERR(bh)) {
5105                 ext4_msg(sb, KERN_ERR, "Can't read superblock on 2nd try");
5106                 ret = PTR_ERR(bh);
5107                 bh = NULL;
5108                 goto out;
5109         }
5110         es = (struct ext4_super_block *)(bh->b_data + offset);
5111         sbi->s_es = es;
5112         if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
5113                 ext4_msg(sb, KERN_ERR, "Magic mismatch, very weird!");
5114                 goto out;
5115         }
5116         *lsb = logical_sb_block;
5117         sbi->s_sbh = bh;
5118         return 0;
5119 out:
5120         brelse(bh);
5121         return ret;
5122 }
5123
5124 static void ext4_hash_info_init(struct super_block *sb)
5125 {
5126         struct ext4_sb_info *sbi = EXT4_SB(sb);
5127         struct ext4_super_block *es = sbi->s_es;
5128         unsigned int i;
5129
5130         for (i = 0; i < 4; i++)
5131                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
5132
5133         sbi->s_def_hash_version = es->s_def_hash_version;
5134         if (ext4_has_feature_dir_index(sb)) {
5135                 i = le32_to_cpu(es->s_flags);
5136                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
5137                         sbi->s_hash_unsigned = 3;
5138                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
5139 #ifdef __CHAR_UNSIGNED__
5140                         if (!sb_rdonly(sb))
5141                                 es->s_flags |=
5142                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
5143                         sbi->s_hash_unsigned = 3;
5144 #else
5145                         if (!sb_rdonly(sb))
5146                                 es->s_flags |=
5147                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
5148 #endif
5149                 }
5150         }
5151 }
5152
5153 static int ext4_block_group_meta_init(struct super_block *sb, int silent)
5154 {
5155         struct ext4_sb_info *sbi = EXT4_SB(sb);
5156         struct ext4_super_block *es = sbi->s_es;
5157         int has_huge_files;
5158
5159         has_huge_files = ext4_has_feature_huge_file(sb);
5160         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
5161                                                       has_huge_files);
5162         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
5163
5164         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
5165         if (ext4_has_feature_64bit(sb)) {
5166                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
5167                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
5168                     !is_power_of_2(sbi->s_desc_size)) {
5169                         ext4_msg(sb, KERN_ERR,
5170                                "unsupported descriptor size %lu",
5171                                sbi->s_desc_size);
5172                         return -EINVAL;
5173                 }
5174         } else
5175                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
5176
5177         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
5178         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
5179
5180         sbi->s_inodes_per_block = sb->s_blocksize / EXT4_INODE_SIZE(sb);
5181         if (sbi->s_inodes_per_block == 0 || sbi->s_blocks_per_group == 0) {
5182                 if (!silent)
5183                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5184                 return -EINVAL;
5185         }
5186         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
5187             sbi->s_inodes_per_group > sb->s_blocksize * 8) {
5188                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
5189                          sbi->s_inodes_per_group);
5190                 return -EINVAL;
5191         }
5192         sbi->s_itb_per_group = sbi->s_inodes_per_group /
5193                                         sbi->s_inodes_per_block;
5194         sbi->s_desc_per_block = sb->s_blocksize / EXT4_DESC_SIZE(sb);
5195         sbi->s_mount_state = le16_to_cpu(es->s_state) & ~EXT4_FC_REPLAY;
5196         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
5197         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
5198
5199         return 0;
5200 }
5201
5202 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
5203 {
5204         struct ext4_super_block *es = NULL;
5205         struct ext4_sb_info *sbi = EXT4_SB(sb);
5206         ext4_fsblk_t logical_sb_block;
5207         struct inode *root;
5208         int needs_recovery;
5209         int err;
5210         ext4_group_t first_not_zeroed;
5211         struct ext4_fs_context *ctx = fc->fs_private;
5212         int silent = fc->sb_flags & SB_SILENT;
5213
5214         /* Set defaults for the variables that will be set during parsing */
5215         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO))
5216                 ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5217
5218         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
5219         sbi->s_sectors_written_start =
5220                 part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
5221
5222         err = ext4_load_super(sb, &logical_sb_block, silent);
5223         if (err)
5224                 goto out_fail;
5225
5226         es = sbi->s_es;
5227         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
5228
5229         err = ext4_init_metadata_csum(sb, es);
5230         if (err)
5231                 goto failed_mount;
5232
5233         ext4_set_def_opts(sb, es);
5234
5235         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
5236         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
5237         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
5238         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
5239         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
5240
5241         /*
5242          * set default s_li_wait_mult for lazyinit, for the case there is
5243          * no mount option specified.
5244          */
5245         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
5246
5247         err = ext4_inode_info_init(sb, es);
5248         if (err)
5249                 goto failed_mount;
5250
5251         err = parse_apply_sb_mount_options(sb, ctx);
5252         if (err < 0)
5253                 goto failed_mount;
5254
5255         sbi->s_def_mount_opt = sbi->s_mount_opt;
5256         sbi->s_def_mount_opt2 = sbi->s_mount_opt2;
5257
5258         err = ext4_check_opt_consistency(fc, sb);
5259         if (err < 0)
5260                 goto failed_mount;
5261
5262         ext4_apply_options(fc, sb);
5263
5264         err = ext4_encoding_init(sb, es);
5265         if (err)
5266                 goto failed_mount;
5267
5268         err = ext4_check_journal_data_mode(sb);
5269         if (err)
5270                 goto failed_mount;
5271
5272         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5273                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5274
5275         /* i_version is always enabled now */
5276         sb->s_flags |= SB_I_VERSION;
5277
5278         err = ext4_check_feature_compatibility(sb, es, silent);
5279         if (err)
5280                 goto failed_mount;
5281
5282         err = ext4_block_group_meta_init(sb, silent);
5283         if (err)
5284                 goto failed_mount;
5285
5286         ext4_hash_info_init(sb);
5287
5288         err = ext4_handle_clustersize(sb);
5289         if (err)
5290                 goto failed_mount;
5291
5292         err = ext4_check_geometry(sb, es);
5293         if (err)
5294                 goto failed_mount;
5295
5296         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5297         spin_lock_init(&sbi->s_error_lock);
5298         INIT_WORK(&sbi->s_sb_upd_work, update_super_work);
5299
5300         err = ext4_group_desc_init(sb, es, logical_sb_block, &first_not_zeroed);
5301         if (err)
5302                 goto failed_mount3;
5303
5304         err = ext4_es_register_shrinker(sbi);
5305         if (err)
5306                 goto failed_mount3;
5307
5308         sbi->s_stripe = ext4_get_stripe_size(sbi);
5309         /*
5310          * It's hard to get stripe aligned blocks if stripe is not aligned with
5311          * cluster, just disable stripe and alert user to simpfy code and avoid
5312          * stripe aligned allocation which will rarely successes.
5313          */
5314         if (sbi->s_stripe > 0 && sbi->s_cluster_ratio > 1 &&
5315             sbi->s_stripe % sbi->s_cluster_ratio != 0) {
5316                 ext4_msg(sb, KERN_WARNING,
5317                          "stripe (%lu) is not aligned with cluster size (%u), "
5318                          "stripe is disabled",
5319                          sbi->s_stripe, sbi->s_cluster_ratio);
5320                 sbi->s_stripe = 0;
5321         }
5322         sbi->s_extent_max_zeroout_kb = 32;
5323
5324         /*
5325          * set up enough so that it can read an inode
5326          */
5327         sb->s_op = &ext4_sops;
5328         sb->s_export_op = &ext4_export_ops;
5329         sb->s_xattr = ext4_xattr_handlers;
5330 #ifdef CONFIG_FS_ENCRYPTION
5331         sb->s_cop = &ext4_cryptops;
5332 #endif
5333 #ifdef CONFIG_FS_VERITY
5334         sb->s_vop = &ext4_verityops;
5335 #endif
5336 #ifdef CONFIG_QUOTA
5337         sb->dq_op = &ext4_quota_operations;
5338         if (ext4_has_feature_quota(sb))
5339                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
5340         else
5341                 sb->s_qcop = &ext4_qctl_operations;
5342         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5343 #endif
5344         super_set_uuid(sb, es->s_uuid, sizeof(es->s_uuid));
5345
5346         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5347         mutex_init(&sbi->s_orphan_lock);
5348
5349         ext4_fast_commit_init(sb);
5350
5351         sb->s_root = NULL;
5352
5353         needs_recovery = (es->s_last_orphan != 0 ||
5354                           ext4_has_feature_orphan_present(sb) ||
5355                           ext4_has_feature_journal_needs_recovery(sb));
5356
5357         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb)) {
5358                 err = ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block));
5359                 if (err)
5360                         goto failed_mount3a;
5361         }
5362
5363         err = -EINVAL;
5364         /*
5365          * The first inode we look at is the journal inode.  Don't try
5366          * root first: it may be modified in the journal!
5367          */
5368         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5369                 err = ext4_load_and_init_journal(sb, es, ctx);
5370                 if (err)
5371                         goto failed_mount3a;
5372         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5373                    ext4_has_feature_journal_needs_recovery(sb)) {
5374                 ext4_msg(sb, KERN_ERR, "required journal recovery "
5375                        "suppressed and not mounted read-only");
5376                 goto failed_mount3a;
5377         } else {
5378                 /* Nojournal mode, all journal mount options are illegal */
5379                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5380                         ext4_msg(sb, KERN_ERR, "can't mount with "
5381                                  "journal_async_commit, fs mounted w/o journal");
5382                         goto failed_mount3a;
5383                 }
5384
5385                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
5386                         ext4_msg(sb, KERN_ERR, "can't mount with "
5387                                  "journal_checksum, fs mounted w/o journal");
5388                         goto failed_mount3a;
5389                 }
5390                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
5391                         ext4_msg(sb, KERN_ERR, "can't mount with "
5392                                  "commit=%lu, fs mounted w/o journal",
5393                                  sbi->s_commit_interval / HZ);
5394                         goto failed_mount3a;
5395                 }
5396                 if (EXT4_MOUNT_DATA_FLAGS &
5397                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
5398                         ext4_msg(sb, KERN_ERR, "can't mount with "
5399                                  "data=, fs mounted w/o journal");
5400                         goto failed_mount3a;
5401                 }
5402                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5403                 clear_opt(sb, JOURNAL_CHECKSUM);
5404                 clear_opt(sb, DATA_FLAGS);
5405                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
5406                 sbi->s_journal = NULL;
5407                 needs_recovery = 0;
5408         }
5409
5410         if (!test_opt(sb, NO_MBCACHE)) {
5411                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
5412                 if (!sbi->s_ea_block_cache) {
5413                         ext4_msg(sb, KERN_ERR,
5414                                  "Failed to create ea_block_cache");
5415                         err = -EINVAL;
5416                         goto failed_mount_wq;
5417                 }
5418
5419                 if (ext4_has_feature_ea_inode(sb)) {
5420                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5421                         if (!sbi->s_ea_inode_cache) {
5422                                 ext4_msg(sb, KERN_ERR,
5423                                          "Failed to create ea_inode_cache");
5424                                 err = -EINVAL;
5425                                 goto failed_mount_wq;
5426                         }
5427                 }
5428         }
5429
5430         /*
5431          * Get the # of file system overhead blocks from the
5432          * superblock if present.
5433          */
5434         sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5435         /* ignore the precalculated value if it is ridiculous */
5436         if (sbi->s_overhead > ext4_blocks_count(es))
5437                 sbi->s_overhead = 0;
5438         /*
5439          * If the bigalloc feature is not enabled recalculating the
5440          * overhead doesn't take long, so we might as well just redo
5441          * it to make sure we are using the correct value.
5442          */
5443         if (!ext4_has_feature_bigalloc(sb))
5444                 sbi->s_overhead = 0;
5445         if (sbi->s_overhead == 0) {
5446                 err = ext4_calculate_overhead(sb);
5447                 if (err)
5448                         goto failed_mount_wq;
5449         }
5450
5451         /*
5452          * The maximum number of concurrent works can be high and
5453          * concurrency isn't really necessary.  Limit it to 1.
5454          */
5455         EXT4_SB(sb)->rsv_conversion_wq =
5456                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5457         if (!EXT4_SB(sb)->rsv_conversion_wq) {
5458                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5459                 err = -ENOMEM;
5460                 goto failed_mount4;
5461         }
5462
5463         /*
5464          * The jbd2_journal_load will have done any necessary log recovery,
5465          * so we can safely mount the rest of the filesystem now.
5466          */
5467
5468         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5469         if (IS_ERR(root)) {
5470                 ext4_msg(sb, KERN_ERR, "get root inode failed");
5471                 err = PTR_ERR(root);
5472                 root = NULL;
5473                 goto failed_mount4;
5474         }
5475         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5476                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5477                 iput(root);
5478                 err = -EFSCORRUPTED;
5479                 goto failed_mount4;
5480         }
5481
5482         generic_set_sb_d_ops(sb);
5483         sb->s_root = d_make_root(root);
5484         if (!sb->s_root) {
5485                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
5486                 err = -ENOMEM;
5487                 goto failed_mount4;
5488         }
5489
5490         err = ext4_setup_super(sb, es, sb_rdonly(sb));
5491         if (err == -EROFS) {
5492                 sb->s_flags |= SB_RDONLY;
5493         } else if (err)
5494                 goto failed_mount4a;
5495
5496         ext4_set_resv_clusters(sb);
5497
5498         if (test_opt(sb, BLOCK_VALIDITY)) {
5499                 err = ext4_setup_system_zone(sb);
5500                 if (err) {
5501                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
5502                                  "zone (%d)", err);
5503                         goto failed_mount4a;
5504                 }
5505         }
5506         ext4_fc_replay_cleanup(sb);
5507
5508         ext4_ext_init(sb);
5509
5510         /*
5511          * Enable optimize_scan if number of groups is > threshold. This can be
5512          * turned off by passing "mb_optimize_scan=0". This can also be
5513          * turned on forcefully by passing "mb_optimize_scan=1".
5514          */
5515         if (!(ctx->spec & EXT4_SPEC_mb_optimize_scan)) {
5516                 if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5517                         set_opt2(sb, MB_OPTIMIZE_SCAN);
5518                 else
5519                         clear_opt2(sb, MB_OPTIMIZE_SCAN);
5520         }
5521
5522         err = ext4_mb_init(sb);
5523         if (err) {
5524                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5525                          err);
5526                 goto failed_mount5;
5527         }
5528
5529         /*
5530          * We can only set up the journal commit callback once
5531          * mballoc is initialized
5532          */
5533         if (sbi->s_journal)
5534                 sbi->s_journal->j_commit_callback =
5535                         ext4_journal_commit_callback;
5536
5537         err = ext4_percpu_param_init(sbi);
5538         if (err)
5539                 goto failed_mount6;
5540
5541         if (ext4_has_feature_flex_bg(sb))
5542                 if (!ext4_fill_flex_info(sb)) {
5543                         ext4_msg(sb, KERN_ERR,
5544                                "unable to initialize "
5545                                "flex_bg meta info!");
5546                         err = -ENOMEM;
5547                         goto failed_mount6;
5548                 }
5549
5550         err = ext4_register_li_request(sb, first_not_zeroed);
5551         if (err)
5552                 goto failed_mount6;
5553
5554         err = ext4_register_sysfs(sb);
5555         if (err)
5556                 goto failed_mount7;
5557
5558         err = ext4_init_orphan_info(sb);
5559         if (err)
5560                 goto failed_mount8;
5561 #ifdef CONFIG_QUOTA
5562         /* Enable quota usage during mount. */
5563         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5564                 err = ext4_enable_quotas(sb);
5565                 if (err)
5566                         goto failed_mount9;
5567         }
5568 #endif  /* CONFIG_QUOTA */
5569
5570         /*
5571          * Save the original bdev mapping's wb_err value which could be
5572          * used to detect the metadata async write error.
5573          */
5574         spin_lock_init(&sbi->s_bdev_wb_lock);
5575         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5576                                  &sbi->s_bdev_wb_err);
5577         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5578         ext4_orphan_cleanup(sb, es);
5579         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5580         /*
5581          * Update the checksum after updating free space/inode counters and
5582          * ext4_orphan_cleanup. Otherwise the superblock can have an incorrect
5583          * checksum in the buffer cache until it is written out and
5584          * e2fsprogs programs trying to open a file system immediately
5585          * after it is mounted can fail.
5586          */
5587         ext4_superblock_csum_set(sb);
5588         if (needs_recovery) {
5589                 ext4_msg(sb, KERN_INFO, "recovery complete");
5590                 err = ext4_mark_recovery_complete(sb, es);
5591                 if (err)
5592                         goto failed_mount10;
5593         }
5594
5595         if (test_opt(sb, DISCARD) && !bdev_max_discard_sectors(sb->s_bdev))
5596                 ext4_msg(sb, KERN_WARNING,
5597                          "mounting with \"discard\" option, but the device does not support discard");
5598
5599         if (es->s_error_count)
5600                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5601
5602         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5603         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5604         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5605         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5606         atomic_set(&sbi->s_warning_count, 0);
5607         atomic_set(&sbi->s_msg_count, 0);
5608
5609         return 0;
5610
5611 failed_mount10:
5612         ext4_quotas_off(sb, EXT4_MAXQUOTAS);
5613 failed_mount9: __maybe_unused
5614         ext4_release_orphan_info(sb);
5615 failed_mount8:
5616         ext4_unregister_sysfs(sb);
5617         kobject_put(&sbi->s_kobj);
5618 failed_mount7:
5619         ext4_unregister_li_request(sb);
5620 failed_mount6:
5621         ext4_mb_release(sb);
5622         ext4_flex_groups_free(sbi);
5623         ext4_percpu_param_destroy(sbi);
5624 failed_mount5:
5625         ext4_ext_release(sb);
5626         ext4_release_system_zone(sb);
5627 failed_mount4a:
5628         dput(sb->s_root);
5629         sb->s_root = NULL;
5630 failed_mount4:
5631         ext4_msg(sb, KERN_ERR, "mount failed");
5632         if (EXT4_SB(sb)->rsv_conversion_wq)
5633                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5634 failed_mount_wq:
5635         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5636         sbi->s_ea_inode_cache = NULL;
5637
5638         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5639         sbi->s_ea_block_cache = NULL;
5640
5641         if (sbi->s_journal) {
5642                 /* flush s_sb_upd_work before journal destroy. */
5643                 flush_work(&sbi->s_sb_upd_work);
5644                 jbd2_journal_destroy(sbi->s_journal);
5645                 sbi->s_journal = NULL;
5646         }
5647 failed_mount3a:
5648         ext4_es_unregister_shrinker(sbi);
5649 failed_mount3:
5650         /* flush s_sb_upd_work before sbi destroy */
5651         flush_work(&sbi->s_sb_upd_work);
5652         del_timer_sync(&sbi->s_err_report);
5653         ext4_stop_mmpd(sbi);
5654         ext4_group_desc_free(sbi);
5655 failed_mount:
5656         if (sbi->s_chksum_driver)
5657                 crypto_free_shash(sbi->s_chksum_driver);
5658
5659 #if IS_ENABLED(CONFIG_UNICODE)
5660         utf8_unload(sb->s_encoding);
5661 #endif
5662
5663 #ifdef CONFIG_QUOTA
5664         for (unsigned int i = 0; i < EXT4_MAXQUOTAS; i++)
5665                 kfree(get_qf_name(sb, sbi, i));
5666 #endif
5667         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5668         brelse(sbi->s_sbh);
5669         if (sbi->s_journal_bdev_file) {
5670                 invalidate_bdev(file_bdev(sbi->s_journal_bdev_file));
5671                 fput(sbi->s_journal_bdev_file);
5672         }
5673 out_fail:
5674         invalidate_bdev(sb->s_bdev);
5675         sb->s_fs_info = NULL;
5676         return err;
5677 }
5678
5679 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5680 {
5681         struct ext4_fs_context *ctx = fc->fs_private;
5682         struct ext4_sb_info *sbi;
5683         const char *descr;
5684         int ret;
5685
5686         sbi = ext4_alloc_sbi(sb);
5687         if (!sbi)
5688                 return -ENOMEM;
5689
5690         fc->s_fs_info = sbi;
5691
5692         /* Cleanup superblock name */
5693         strreplace(sb->s_id, '/', '!');
5694
5695         sbi->s_sb_block = 1;    /* Default super block location */
5696         if (ctx->spec & EXT4_SPEC_s_sb_block)
5697                 sbi->s_sb_block = ctx->s_sb_block;
5698
5699         ret = __ext4_fill_super(fc, sb);
5700         if (ret < 0)
5701                 goto free_sbi;
5702
5703         if (sbi->s_journal) {
5704                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5705                         descr = " journalled data mode";
5706                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5707                         descr = " ordered data mode";
5708                 else
5709                         descr = " writeback data mode";
5710         } else
5711                 descr = "out journal";
5712
5713         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5714                 ext4_msg(sb, KERN_INFO, "mounted filesystem %pU %s with%s. "
5715                          "Quota mode: %s.", &sb->s_uuid,
5716                          sb_rdonly(sb) ? "ro" : "r/w", descr,
5717                          ext4_quota_mode(sb));
5718
5719         /* Update the s_overhead_clusters if necessary */
5720         ext4_update_overhead(sb, false);
5721         return 0;
5722
5723 free_sbi:
5724         ext4_free_sbi(sbi);
5725         fc->s_fs_info = NULL;
5726         return ret;
5727 }
5728
5729 static int ext4_get_tree(struct fs_context *fc)
5730 {
5731         return get_tree_bdev(fc, ext4_fill_super);
5732 }
5733
5734 /*
5735  * Setup any per-fs journal parameters now.  We'll do this both on
5736  * initial mount, once the journal has been initialised but before we've
5737  * done any recovery; and again on any subsequent remount.
5738  */
5739 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5740 {
5741         struct ext4_sb_info *sbi = EXT4_SB(sb);
5742
5743         journal->j_commit_interval = sbi->s_commit_interval;
5744         journal->j_min_batch_time = sbi->s_min_batch_time;
5745         journal->j_max_batch_time = sbi->s_max_batch_time;
5746         ext4_fc_init(sb, journal);
5747
5748         write_lock(&journal->j_state_lock);
5749         if (test_opt(sb, BARRIER))
5750                 journal->j_flags |= JBD2_BARRIER;
5751         else
5752                 journal->j_flags &= ~JBD2_BARRIER;
5753         if (test_opt(sb, DATA_ERR_ABORT))
5754                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5755         else
5756                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5757         /*
5758          * Always enable journal cycle record option, letting the journal
5759          * records log transactions continuously between each mount.
5760          */
5761         journal->j_flags |= JBD2_CYCLE_RECORD;
5762         write_unlock(&journal->j_state_lock);
5763 }
5764
5765 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5766                                              unsigned int journal_inum)
5767 {
5768         struct inode *journal_inode;
5769
5770         /*
5771          * Test for the existence of a valid inode on disk.  Bad things
5772          * happen if we iget() an unused inode, as the subsequent iput()
5773          * will try to delete it.
5774          */
5775         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5776         if (IS_ERR(journal_inode)) {
5777                 ext4_msg(sb, KERN_ERR, "no journal found");
5778                 return ERR_CAST(journal_inode);
5779         }
5780         if (!journal_inode->i_nlink) {
5781                 make_bad_inode(journal_inode);
5782                 iput(journal_inode);
5783                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5784                 return ERR_PTR(-EFSCORRUPTED);
5785         }
5786         if (!S_ISREG(journal_inode->i_mode) || IS_ENCRYPTED(journal_inode)) {
5787                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5788                 iput(journal_inode);
5789                 return ERR_PTR(-EFSCORRUPTED);
5790         }
5791
5792         ext4_debug("Journal inode found at %p: %lld bytes\n",
5793                   journal_inode, journal_inode->i_size);
5794         return journal_inode;
5795 }
5796
5797 static int ext4_journal_bmap(journal_t *journal, sector_t *block)
5798 {
5799         struct ext4_map_blocks map;
5800         int ret;
5801
5802         if (journal->j_inode == NULL)
5803                 return 0;
5804
5805         map.m_lblk = *block;
5806         map.m_len = 1;
5807         ret = ext4_map_blocks(NULL, journal->j_inode, &map, 0);
5808         if (ret <= 0) {
5809                 ext4_msg(journal->j_inode->i_sb, KERN_CRIT,
5810                          "journal bmap failed: block %llu ret %d\n",
5811                          *block, ret);
5812                 jbd2_journal_abort(journal, ret ? ret : -EIO);
5813                 return ret;
5814         }
5815         *block = map.m_pblk;
5816         return 0;
5817 }
5818
5819 static journal_t *ext4_open_inode_journal(struct super_block *sb,
5820                                           unsigned int journal_inum)
5821 {
5822         struct inode *journal_inode;
5823         journal_t *journal;
5824
5825         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5826         if (IS_ERR(journal_inode))
5827                 return ERR_CAST(journal_inode);
5828
5829         journal = jbd2_journal_init_inode(journal_inode);
5830         if (IS_ERR(journal)) {
5831                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5832                 iput(journal_inode);
5833                 return ERR_CAST(journal);
5834         }
5835         journal->j_private = sb;
5836         journal->j_bmap = ext4_journal_bmap;
5837         ext4_init_journal_params(sb, journal);
5838         return journal;
5839 }
5840
5841 static struct file *ext4_get_journal_blkdev(struct super_block *sb,
5842                                         dev_t j_dev, ext4_fsblk_t *j_start,
5843                                         ext4_fsblk_t *j_len)
5844 {
5845         struct buffer_head *bh;
5846         struct block_device *bdev;
5847         struct file *bdev_file;
5848         int hblock, blocksize;
5849         ext4_fsblk_t sb_block;
5850         unsigned long offset;
5851         struct ext4_super_block *es;
5852         int errno;
5853
5854         bdev_file = bdev_file_open_by_dev(j_dev,
5855                 BLK_OPEN_READ | BLK_OPEN_WRITE | BLK_OPEN_RESTRICT_WRITES,
5856                 sb, &fs_holder_ops);
5857         if (IS_ERR(bdev_file)) {
5858                 ext4_msg(sb, KERN_ERR,
5859                          "failed to open journal device unknown-block(%u,%u) %ld",
5860                          MAJOR(j_dev), MINOR(j_dev), PTR_ERR(bdev_file));
5861                 return bdev_file;
5862         }
5863
5864         bdev = file_bdev(bdev_file);
5865         blocksize = sb->s_blocksize;
5866         hblock = bdev_logical_block_size(bdev);
5867         if (blocksize < hblock) {
5868                 ext4_msg(sb, KERN_ERR,
5869                         "blocksize too small for journal device");
5870                 errno = -EINVAL;
5871                 goto out_bdev;
5872         }
5873
5874         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5875         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5876         set_blocksize(bdev, blocksize);
5877         bh = __bread(bdev, sb_block, blocksize);
5878         if (!bh) {
5879                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5880                        "external journal");
5881                 errno = -EINVAL;
5882                 goto out_bdev;
5883         }
5884
5885         es = (struct ext4_super_block *) (bh->b_data + offset);
5886         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5887             !(le32_to_cpu(es->s_feature_incompat) &
5888               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5889                 ext4_msg(sb, KERN_ERR, "external journal has bad superblock");
5890                 errno = -EFSCORRUPTED;
5891                 goto out_bh;
5892         }
5893
5894         if ((le32_to_cpu(es->s_feature_ro_compat) &
5895              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5896             es->s_checksum != ext4_superblock_csum(sb, es)) {
5897                 ext4_msg(sb, KERN_ERR, "external journal has corrupt superblock");
5898                 errno = -EFSCORRUPTED;
5899                 goto out_bh;
5900         }
5901
5902         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5903                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5904                 errno = -EFSCORRUPTED;
5905                 goto out_bh;
5906         }
5907
5908         *j_start = sb_block + 1;
5909         *j_len = ext4_blocks_count(es);
5910         brelse(bh);
5911         return bdev_file;
5912
5913 out_bh:
5914         brelse(bh);
5915 out_bdev:
5916         fput(bdev_file);
5917         return ERR_PTR(errno);
5918 }
5919
5920 static journal_t *ext4_open_dev_journal(struct super_block *sb,
5921                                         dev_t j_dev)
5922 {
5923         journal_t *journal;
5924         ext4_fsblk_t j_start;
5925         ext4_fsblk_t j_len;
5926         struct file *bdev_file;
5927         int errno = 0;
5928
5929         bdev_file = ext4_get_journal_blkdev(sb, j_dev, &j_start, &j_len);
5930         if (IS_ERR(bdev_file))
5931                 return ERR_CAST(bdev_file);
5932
5933         journal = jbd2_journal_init_dev(file_bdev(bdev_file), sb->s_bdev, j_start,
5934                                         j_len, sb->s_blocksize);
5935         if (IS_ERR(journal)) {
5936                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5937                 errno = PTR_ERR(journal);
5938                 goto out_bdev;
5939         }
5940         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5941                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5942                                         "user (unsupported) - %d",
5943                         be32_to_cpu(journal->j_superblock->s_nr_users));
5944                 errno = -EINVAL;
5945                 goto out_journal;
5946         }
5947         journal->j_private = sb;
5948         EXT4_SB(sb)->s_journal_bdev_file = bdev_file;
5949         ext4_init_journal_params(sb, journal);
5950         return journal;
5951
5952 out_journal:
5953         jbd2_journal_destroy(journal);
5954 out_bdev:
5955         fput(bdev_file);
5956         return ERR_PTR(errno);
5957 }
5958
5959 static int ext4_load_journal(struct super_block *sb,
5960                              struct ext4_super_block *es,
5961                              unsigned long journal_devnum)
5962 {
5963         journal_t *journal;
5964         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5965         dev_t journal_dev;
5966         int err = 0;
5967         int really_read_only;
5968         int journal_dev_ro;
5969
5970         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5971                 return -EFSCORRUPTED;
5972
5973         if (journal_devnum &&
5974             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5975                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5976                         "numbers have changed");
5977                 journal_dev = new_decode_dev(journal_devnum);
5978         } else
5979                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5980
5981         if (journal_inum && journal_dev) {
5982                 ext4_msg(sb, KERN_ERR,
5983                          "filesystem has both journal inode and journal device!");
5984                 return -EINVAL;
5985         }
5986
5987         if (journal_inum) {
5988                 journal = ext4_open_inode_journal(sb, journal_inum);
5989                 if (IS_ERR(journal))
5990                         return PTR_ERR(journal);
5991         } else {
5992                 journal = ext4_open_dev_journal(sb, journal_dev);
5993                 if (IS_ERR(journal))
5994                         return PTR_ERR(journal);
5995         }
5996
5997         journal_dev_ro = bdev_read_only(journal->j_dev);
5998         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5999
6000         if (journal_dev_ro && !sb_rdonly(sb)) {
6001                 ext4_msg(sb, KERN_ERR,
6002                          "journal device read-only, try mounting with '-o ro'");
6003                 err = -EROFS;
6004                 goto err_out;
6005         }
6006
6007         /*
6008          * Are we loading a blank journal or performing recovery after a
6009          * crash?  For recovery, we need to check in advance whether we
6010          * can get read-write access to the device.
6011          */
6012         if (ext4_has_feature_journal_needs_recovery(sb)) {
6013                 if (sb_rdonly(sb)) {
6014                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
6015                                         "required on readonly filesystem");
6016                         if (really_read_only) {
6017                                 ext4_msg(sb, KERN_ERR, "write access "
6018                                         "unavailable, cannot proceed "
6019                                         "(try mounting with noload)");
6020                                 err = -EROFS;
6021                                 goto err_out;
6022                         }
6023                         ext4_msg(sb, KERN_INFO, "write access will "
6024                                "be enabled during recovery");
6025                 }
6026         }
6027
6028         if (!(journal->j_flags & JBD2_BARRIER))
6029                 ext4_msg(sb, KERN_INFO, "barriers disabled");
6030
6031         if (!ext4_has_feature_journal_needs_recovery(sb))
6032                 err = jbd2_journal_wipe(journal, !really_read_only);
6033         if (!err) {
6034                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
6035                 __le16 orig_state;
6036                 bool changed = false;
6037
6038                 if (save)
6039                         memcpy(save, ((char *) es) +
6040                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
6041                 err = jbd2_journal_load(journal);
6042                 if (save && memcmp(((char *) es) + EXT4_S_ERR_START,
6043                                    save, EXT4_S_ERR_LEN)) {
6044                         memcpy(((char *) es) + EXT4_S_ERR_START,
6045                                save, EXT4_S_ERR_LEN);
6046                         changed = true;
6047                 }
6048                 kfree(save);
6049                 orig_state = es->s_state;
6050                 es->s_state |= cpu_to_le16(EXT4_SB(sb)->s_mount_state &
6051                                            EXT4_ERROR_FS);
6052                 if (orig_state != es->s_state)
6053                         changed = true;
6054                 /* Write out restored error information to the superblock */
6055                 if (changed && !really_read_only) {
6056                         int err2;
6057                         err2 = ext4_commit_super(sb);
6058                         err = err ? : err2;
6059                 }
6060         }
6061
6062         if (err) {
6063                 ext4_msg(sb, KERN_ERR, "error loading journal");
6064                 goto err_out;
6065         }
6066
6067         EXT4_SB(sb)->s_journal = journal;
6068         err = ext4_clear_journal_err(sb, es);
6069         if (err) {
6070                 EXT4_SB(sb)->s_journal = NULL;
6071                 jbd2_journal_destroy(journal);
6072                 return err;
6073         }
6074
6075         if (!really_read_only && journal_devnum &&
6076             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
6077                 es->s_journal_dev = cpu_to_le32(journal_devnum);
6078                 ext4_commit_super(sb);
6079         }
6080         if (!really_read_only && journal_inum &&
6081             journal_inum != le32_to_cpu(es->s_journal_inum)) {
6082                 es->s_journal_inum = cpu_to_le32(journal_inum);
6083                 ext4_commit_super(sb);
6084         }
6085
6086         return 0;
6087
6088 err_out:
6089         jbd2_journal_destroy(journal);
6090         return err;
6091 }
6092
6093 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
6094 static void ext4_update_super(struct super_block *sb)
6095 {
6096         struct ext4_sb_info *sbi = EXT4_SB(sb);
6097         struct ext4_super_block *es = sbi->s_es;
6098         struct buffer_head *sbh = sbi->s_sbh;
6099
6100         lock_buffer(sbh);
6101         /*
6102          * If the file system is mounted read-only, don't update the
6103          * superblock write time.  This avoids updating the superblock
6104          * write time when we are mounting the root file system
6105          * read/only but we need to replay the journal; at that point,
6106          * for people who are east of GMT and who make their clock
6107          * tick in localtime for Windows bug-for-bug compatibility,
6108          * the clock is set in the future, and this will cause e2fsck
6109          * to complain and force a full file system check.
6110          */
6111         if (!sb_rdonly(sb))
6112                 ext4_update_tstamp(es, s_wtime);
6113         es->s_kbytes_written =
6114                 cpu_to_le64(sbi->s_kbytes_written +
6115                     ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
6116                       sbi->s_sectors_written_start) >> 1));
6117         if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
6118                 ext4_free_blocks_count_set(es,
6119                         EXT4_C2B(sbi, percpu_counter_sum_positive(
6120                                 &sbi->s_freeclusters_counter)));
6121         if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
6122                 es->s_free_inodes_count =
6123                         cpu_to_le32(percpu_counter_sum_positive(
6124                                 &sbi->s_freeinodes_counter));
6125         /* Copy error information to the on-disk superblock */
6126         spin_lock(&sbi->s_error_lock);
6127         if (sbi->s_add_error_count > 0) {
6128                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6129                 if (!es->s_first_error_time && !es->s_first_error_time_hi) {
6130                         __ext4_update_tstamp(&es->s_first_error_time,
6131                                              &es->s_first_error_time_hi,
6132                                              sbi->s_first_error_time);
6133                         strncpy(es->s_first_error_func, sbi->s_first_error_func,
6134                                 sizeof(es->s_first_error_func));
6135                         es->s_first_error_line =
6136                                 cpu_to_le32(sbi->s_first_error_line);
6137                         es->s_first_error_ino =
6138                                 cpu_to_le32(sbi->s_first_error_ino);
6139                         es->s_first_error_block =
6140                                 cpu_to_le64(sbi->s_first_error_block);
6141                         es->s_first_error_errcode =
6142                                 ext4_errno_to_code(sbi->s_first_error_code);
6143                 }
6144                 __ext4_update_tstamp(&es->s_last_error_time,
6145                                      &es->s_last_error_time_hi,
6146                                      sbi->s_last_error_time);
6147                 strncpy(es->s_last_error_func, sbi->s_last_error_func,
6148                         sizeof(es->s_last_error_func));
6149                 es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
6150                 es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
6151                 es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
6152                 es->s_last_error_errcode =
6153                                 ext4_errno_to_code(sbi->s_last_error_code);
6154                 /*
6155                  * Start the daily error reporting function if it hasn't been
6156                  * started already
6157                  */
6158                 if (!es->s_error_count)
6159                         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
6160                 le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
6161                 sbi->s_add_error_count = 0;
6162         }
6163         spin_unlock(&sbi->s_error_lock);
6164
6165         ext4_superblock_csum_set(sb);
6166         unlock_buffer(sbh);
6167 }
6168
6169 static int ext4_commit_super(struct super_block *sb)
6170 {
6171         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
6172
6173         if (!sbh)
6174                 return -EINVAL;
6175         if (block_device_ejected(sb))
6176                 return -ENODEV;
6177
6178         ext4_update_super(sb);
6179
6180         lock_buffer(sbh);
6181         /* Buffer got discarded which means block device got invalidated */
6182         if (!buffer_mapped(sbh)) {
6183                 unlock_buffer(sbh);
6184                 return -EIO;
6185         }
6186
6187         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
6188                 /*
6189                  * Oh, dear.  A previous attempt to write the
6190                  * superblock failed.  This could happen because the
6191                  * USB device was yanked out.  Or it could happen to
6192                  * be a transient write error and maybe the block will
6193                  * be remapped.  Nothing we can do but to retry the
6194                  * write and hope for the best.
6195                  */
6196                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
6197                        "superblock detected");
6198                 clear_buffer_write_io_error(sbh);
6199                 set_buffer_uptodate(sbh);
6200         }
6201         get_bh(sbh);
6202         /* Clear potential dirty bit if it was journalled update */
6203         clear_buffer_dirty(sbh);
6204         sbh->b_end_io = end_buffer_write_sync;
6205         submit_bh(REQ_OP_WRITE | REQ_SYNC |
6206                   (test_opt(sb, BARRIER) ? REQ_FUA : 0), sbh);
6207         wait_on_buffer(sbh);
6208         if (buffer_write_io_error(sbh)) {
6209                 ext4_msg(sb, KERN_ERR, "I/O error while writing "
6210                        "superblock");
6211                 clear_buffer_write_io_error(sbh);
6212                 set_buffer_uptodate(sbh);
6213                 return -EIO;
6214         }
6215         return 0;
6216 }
6217
6218 /*
6219  * Have we just finished recovery?  If so, and if we are mounting (or
6220  * remounting) the filesystem readonly, then we will end up with a
6221  * consistent fs on disk.  Record that fact.
6222  */
6223 static int ext4_mark_recovery_complete(struct super_block *sb,
6224                                        struct ext4_super_block *es)
6225 {
6226         int err;
6227         journal_t *journal = EXT4_SB(sb)->s_journal;
6228
6229         if (!ext4_has_feature_journal(sb)) {
6230                 if (journal != NULL) {
6231                         ext4_error(sb, "Journal got removed while the fs was "
6232                                    "mounted!");
6233                         return -EFSCORRUPTED;
6234                 }
6235                 return 0;
6236         }
6237         jbd2_journal_lock_updates(journal);
6238         err = jbd2_journal_flush(journal, 0);
6239         if (err < 0)
6240                 goto out;
6241
6242         if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6243             ext4_has_feature_orphan_present(sb))) {
6244                 if (!ext4_orphan_file_empty(sb)) {
6245                         ext4_error(sb, "Orphan file not empty on read-only fs.");
6246                         err = -EFSCORRUPTED;
6247                         goto out;
6248                 }
6249                 ext4_clear_feature_journal_needs_recovery(sb);
6250                 ext4_clear_feature_orphan_present(sb);
6251                 ext4_commit_super(sb);
6252         }
6253 out:
6254         jbd2_journal_unlock_updates(journal);
6255         return err;
6256 }
6257
6258 /*
6259  * If we are mounting (or read-write remounting) a filesystem whose journal
6260  * has recorded an error from a previous lifetime, move that error to the
6261  * main filesystem now.
6262  */
6263 static int ext4_clear_journal_err(struct super_block *sb,
6264                                    struct ext4_super_block *es)
6265 {
6266         journal_t *journal;
6267         int j_errno;
6268         const char *errstr;
6269
6270         if (!ext4_has_feature_journal(sb)) {
6271                 ext4_error(sb, "Journal got removed while the fs was mounted!");
6272                 return -EFSCORRUPTED;
6273         }
6274
6275         journal = EXT4_SB(sb)->s_journal;
6276
6277         /*
6278          * Now check for any error status which may have been recorded in the
6279          * journal by a prior ext4_error() or ext4_abort()
6280          */
6281
6282         j_errno = jbd2_journal_errno(journal);
6283         if (j_errno) {
6284                 char nbuf[16];
6285
6286                 errstr = ext4_decode_error(sb, j_errno, nbuf);
6287                 ext4_warning(sb, "Filesystem error recorded "
6288                              "from previous mount: %s", errstr);
6289
6290                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6291                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6292                 j_errno = ext4_commit_super(sb);
6293                 if (j_errno)
6294                         return j_errno;
6295                 ext4_warning(sb, "Marked fs in need of filesystem check.");
6296
6297                 jbd2_journal_clear_err(journal);
6298                 jbd2_journal_update_sb_errno(journal);
6299         }
6300         return 0;
6301 }
6302
6303 /*
6304  * Force the running and committing transactions to commit,
6305  * and wait on the commit.
6306  */
6307 int ext4_force_commit(struct super_block *sb)
6308 {
6309         return ext4_journal_force_commit(EXT4_SB(sb)->s_journal);
6310 }
6311
6312 static int ext4_sync_fs(struct super_block *sb, int wait)
6313 {
6314         int ret = 0;
6315         tid_t target;
6316         bool needs_barrier = false;
6317         struct ext4_sb_info *sbi = EXT4_SB(sb);
6318
6319         if (unlikely(ext4_forced_shutdown(sb)))
6320                 return 0;
6321
6322         trace_ext4_sync_fs(sb, wait);
6323         flush_workqueue(sbi->rsv_conversion_wq);
6324         /*
6325          * Writeback quota in non-journalled quota case - journalled quota has
6326          * no dirty dquots
6327          */
6328         dquot_writeback_dquots(sb, -1);
6329         /*
6330          * Data writeback is possible w/o journal transaction, so barrier must
6331          * being sent at the end of the function. But we can skip it if
6332          * transaction_commit will do it for us.
6333          */
6334         if (sbi->s_journal) {
6335                 target = jbd2_get_latest_transaction(sbi->s_journal);
6336                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6337                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6338                         needs_barrier = true;
6339
6340                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6341                         if (wait)
6342                                 ret = jbd2_log_wait_commit(sbi->s_journal,
6343                                                            target);
6344                 }
6345         } else if (wait && test_opt(sb, BARRIER))
6346                 needs_barrier = true;
6347         if (needs_barrier) {
6348                 int err;
6349                 err = blkdev_issue_flush(sb->s_bdev);
6350                 if (!ret)
6351                         ret = err;
6352         }
6353
6354         return ret;
6355 }
6356
6357 /*
6358  * LVM calls this function before a (read-only) snapshot is created.  This
6359  * gives us a chance to flush the journal completely and mark the fs clean.
6360  *
6361  * Note that only this function cannot bring a filesystem to be in a clean
6362  * state independently. It relies on upper layer to stop all data & metadata
6363  * modifications.
6364  */
6365 static int ext4_freeze(struct super_block *sb)
6366 {
6367         int error = 0;
6368         journal_t *journal = EXT4_SB(sb)->s_journal;
6369
6370         if (journal) {
6371                 /* Now we set up the journal barrier. */
6372                 jbd2_journal_lock_updates(journal);
6373
6374                 /*
6375                  * Don't clear the needs_recovery flag if we failed to
6376                  * flush the journal.
6377                  */
6378                 error = jbd2_journal_flush(journal, 0);
6379                 if (error < 0)
6380                         goto out;
6381
6382                 /* Journal blocked and flushed, clear needs_recovery flag. */
6383                 ext4_clear_feature_journal_needs_recovery(sb);
6384                 if (ext4_orphan_file_empty(sb))
6385                         ext4_clear_feature_orphan_present(sb);
6386         }
6387
6388         error = ext4_commit_super(sb);
6389 out:
6390         if (journal)
6391                 /* we rely on upper layer to stop further updates */
6392                 jbd2_journal_unlock_updates(journal);
6393         return error;
6394 }
6395
6396 /*
6397  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6398  * flag here, even though the filesystem is not technically dirty yet.
6399  */
6400 static int ext4_unfreeze(struct super_block *sb)
6401 {
6402         if (ext4_forced_shutdown(sb))
6403                 return 0;
6404
6405         if (EXT4_SB(sb)->s_journal) {
6406                 /* Reset the needs_recovery flag before the fs is unlocked. */
6407                 ext4_set_feature_journal_needs_recovery(sb);
6408                 if (ext4_has_feature_orphan_file(sb))
6409                         ext4_set_feature_orphan_present(sb);
6410         }
6411
6412         ext4_commit_super(sb);
6413         return 0;
6414 }
6415
6416 /*
6417  * Structure to save mount options for ext4_remount's benefit
6418  */
6419 struct ext4_mount_options {
6420         unsigned long s_mount_opt;
6421         unsigned long s_mount_opt2;
6422         kuid_t s_resuid;
6423         kgid_t s_resgid;
6424         unsigned long s_commit_interval;
6425         u32 s_min_batch_time, s_max_batch_time;
6426 #ifdef CONFIG_QUOTA
6427         int s_jquota_fmt;
6428         char *s_qf_names[EXT4_MAXQUOTAS];
6429 #endif
6430 };
6431
6432 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6433 {
6434         struct ext4_fs_context *ctx = fc->fs_private;
6435         struct ext4_super_block *es;
6436         struct ext4_sb_info *sbi = EXT4_SB(sb);
6437         unsigned long old_sb_flags;
6438         struct ext4_mount_options old_opts;
6439         ext4_group_t g;
6440         int err = 0;
6441         int alloc_ctx;
6442 #ifdef CONFIG_QUOTA
6443         int enable_quota = 0;
6444         int i, j;
6445         char *to_free[EXT4_MAXQUOTAS];
6446 #endif
6447
6448
6449         /* Store the original options */
6450         old_sb_flags = sb->s_flags;
6451         old_opts.s_mount_opt = sbi->s_mount_opt;
6452         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6453         old_opts.s_resuid = sbi->s_resuid;
6454         old_opts.s_resgid = sbi->s_resgid;
6455         old_opts.s_commit_interval = sbi->s_commit_interval;
6456         old_opts.s_min_batch_time = sbi->s_min_batch_time;
6457         old_opts.s_max_batch_time = sbi->s_max_batch_time;
6458 #ifdef CONFIG_QUOTA
6459         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6460         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6461                 if (sbi->s_qf_names[i]) {
6462                         char *qf_name = get_qf_name(sb, sbi, i);
6463
6464                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6465                         if (!old_opts.s_qf_names[i]) {
6466                                 for (j = 0; j < i; j++)
6467                                         kfree(old_opts.s_qf_names[j]);
6468                                 return -ENOMEM;
6469                         }
6470                 } else
6471                         old_opts.s_qf_names[i] = NULL;
6472 #endif
6473         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)) {
6474                 if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6475                         ctx->journal_ioprio =
6476                                 sbi->s_journal->j_task->io_context->ioprio;
6477                 else
6478                         ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
6479
6480         }
6481
6482         /*
6483          * Changing the DIOREAD_NOLOCK or DELALLOC mount options may cause
6484          * two calls to ext4_should_dioread_nolock() to return inconsistent
6485          * values, triggering WARN_ON in ext4_add_complete_io(). we grab
6486          * here s_writepages_rwsem to avoid race between writepages ops and
6487          * remount.
6488          */
6489         alloc_ctx = ext4_writepages_down_write(sb);
6490         ext4_apply_options(fc, sb);
6491         ext4_writepages_up_write(sb, alloc_ctx);
6492
6493         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6494             test_opt(sb, JOURNAL_CHECKSUM)) {
6495                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6496                          "during remount not supported; ignoring");
6497                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6498         }
6499
6500         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6501                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6502                         ext4_msg(sb, KERN_ERR, "can't mount with "
6503                                  "both data=journal and delalloc");
6504                         err = -EINVAL;
6505                         goto restore_opts;
6506                 }
6507                 if (test_opt(sb, DIOREAD_NOLOCK)) {
6508                         ext4_msg(sb, KERN_ERR, "can't mount with "
6509                                  "both data=journal and dioread_nolock");
6510                         err = -EINVAL;
6511                         goto restore_opts;
6512                 }
6513         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6514                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6515                         ext4_msg(sb, KERN_ERR, "can't mount with "
6516                                 "journal_async_commit in data=ordered mode");
6517                         err = -EINVAL;
6518                         goto restore_opts;
6519                 }
6520         }
6521
6522         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6523                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6524                 err = -EINVAL;
6525                 goto restore_opts;
6526         }
6527
6528         if (test_opt2(sb, ABORT))
6529                 ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6530
6531         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6532                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6533
6534         es = sbi->s_es;
6535
6536         if (sbi->s_journal) {
6537                 ext4_init_journal_params(sb, sbi->s_journal);
6538                 set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6539         }
6540
6541         /* Flush outstanding errors before changing fs state */
6542         flush_work(&sbi->s_sb_upd_work);
6543
6544         if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6545                 if (ext4_forced_shutdown(sb)) {
6546                         err = -EROFS;
6547                         goto restore_opts;
6548                 }
6549
6550                 if (fc->sb_flags & SB_RDONLY) {
6551                         err = sync_filesystem(sb);
6552                         if (err < 0)
6553                                 goto restore_opts;
6554                         err = dquot_suspend(sb, -1);
6555                         if (err < 0)
6556                                 goto restore_opts;
6557
6558                         /*
6559                          * First of all, the unconditional stuff we have to do
6560                          * to disable replay of the journal when we next remount
6561                          */
6562                         sb->s_flags |= SB_RDONLY;
6563
6564                         /*
6565                          * OK, test if we are remounting a valid rw partition
6566                          * readonly, and if so set the rdonly flag and then
6567                          * mark the partition as valid again.
6568                          */
6569                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6570                             (sbi->s_mount_state & EXT4_VALID_FS))
6571                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
6572
6573                         if (sbi->s_journal) {
6574                                 /*
6575                                  * We let remount-ro finish even if marking fs
6576                                  * as clean failed...
6577                                  */
6578                                 ext4_mark_recovery_complete(sb, es);
6579                         }
6580                 } else {
6581                         /* Make sure we can mount this feature set readwrite */
6582                         if (ext4_has_feature_readonly(sb) ||
6583                             !ext4_feature_set_ok(sb, 0)) {
6584                                 err = -EROFS;
6585                                 goto restore_opts;
6586                         }
6587                         /*
6588                          * Make sure the group descriptor checksums
6589                          * are sane.  If they aren't, refuse to remount r/w.
6590                          */
6591                         for (g = 0; g < sbi->s_groups_count; g++) {
6592                                 struct ext4_group_desc *gdp =
6593                                         ext4_get_group_desc(sb, g, NULL);
6594
6595                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6596                                         ext4_msg(sb, KERN_ERR,
6597                "ext4_remount: Checksum for group %u failed (%u!=%u)",
6598                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6599                                                le16_to_cpu(gdp->bg_checksum));
6600                                         err = -EFSBADCRC;
6601                                         goto restore_opts;
6602                                 }
6603                         }
6604
6605                         /*
6606                          * If we have an unprocessed orphan list hanging
6607                          * around from a previously readonly bdev mount,
6608                          * require a full umount/remount for now.
6609                          */
6610                         if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6611                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
6612                                        "remount RDWR because of unprocessed "
6613                                        "orphan inode list.  Please "
6614                                        "umount/remount instead");
6615                                 err = -EINVAL;
6616                                 goto restore_opts;
6617                         }
6618
6619                         /*
6620                          * Mounting a RDONLY partition read-write, so reread
6621                          * and store the current valid flag.  (It may have
6622                          * been changed by e2fsck since we originally mounted
6623                          * the partition.)
6624                          */
6625                         if (sbi->s_journal) {
6626                                 err = ext4_clear_journal_err(sb, es);
6627                                 if (err)
6628                                         goto restore_opts;
6629                         }
6630                         sbi->s_mount_state = (le16_to_cpu(es->s_state) &
6631                                               ~EXT4_FC_REPLAY);
6632
6633                         err = ext4_setup_super(sb, es, 0);
6634                         if (err)
6635                                 goto restore_opts;
6636
6637                         sb->s_flags &= ~SB_RDONLY;
6638                         if (ext4_has_feature_mmp(sb)) {
6639                                 err = ext4_multi_mount_protect(sb,
6640                                                 le64_to_cpu(es->s_mmp_block));
6641                                 if (err)
6642                                         goto restore_opts;
6643                         }
6644 #ifdef CONFIG_QUOTA
6645                         enable_quota = 1;
6646 #endif
6647                 }
6648         }
6649
6650         /*
6651          * Handle creation of system zone data early because it can fail.
6652          * Releasing of existing data is done when we are sure remount will
6653          * succeed.
6654          */
6655         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6656                 err = ext4_setup_system_zone(sb);
6657                 if (err)
6658                         goto restore_opts;
6659         }
6660
6661         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6662                 err = ext4_commit_super(sb);
6663                 if (err)
6664                         goto restore_opts;
6665         }
6666
6667 #ifdef CONFIG_QUOTA
6668         if (enable_quota) {
6669                 if (sb_any_quota_suspended(sb))
6670                         dquot_resume(sb, -1);
6671                 else if (ext4_has_feature_quota(sb)) {
6672                         err = ext4_enable_quotas(sb);
6673                         if (err)
6674                                 goto restore_opts;
6675                 }
6676         }
6677         /* Release old quota file names */
6678         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6679                 kfree(old_opts.s_qf_names[i]);
6680 #endif
6681         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6682                 ext4_release_system_zone(sb);
6683
6684         /*
6685          * Reinitialize lazy itable initialization thread based on
6686          * current settings
6687          */
6688         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6689                 ext4_unregister_li_request(sb);
6690         else {
6691                 ext4_group_t first_not_zeroed;
6692                 first_not_zeroed = ext4_has_uninit_itable(sb);
6693                 ext4_register_li_request(sb, first_not_zeroed);
6694         }
6695
6696         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6697                 ext4_stop_mmpd(sbi);
6698
6699         return 0;
6700
6701 restore_opts:
6702         /*
6703          * If there was a failing r/w to ro transition, we may need to
6704          * re-enable quota
6705          */
6706         if (sb_rdonly(sb) && !(old_sb_flags & SB_RDONLY) &&
6707             sb_any_quota_suspended(sb))
6708                 dquot_resume(sb, -1);
6709
6710         alloc_ctx = ext4_writepages_down_write(sb);
6711         sb->s_flags = old_sb_flags;
6712         sbi->s_mount_opt = old_opts.s_mount_opt;
6713         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6714         sbi->s_resuid = old_opts.s_resuid;
6715         sbi->s_resgid = old_opts.s_resgid;
6716         sbi->s_commit_interval = old_opts.s_commit_interval;
6717         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6718         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6719         ext4_writepages_up_write(sb, alloc_ctx);
6720
6721         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6722                 ext4_release_system_zone(sb);
6723 #ifdef CONFIG_QUOTA
6724         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6725         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6726                 to_free[i] = get_qf_name(sb, sbi, i);
6727                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6728         }
6729         synchronize_rcu();
6730         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6731                 kfree(to_free[i]);
6732 #endif
6733         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6734                 ext4_stop_mmpd(sbi);
6735         return err;
6736 }
6737
6738 static int ext4_reconfigure(struct fs_context *fc)
6739 {
6740         struct super_block *sb = fc->root->d_sb;
6741         int ret;
6742
6743         fc->s_fs_info = EXT4_SB(sb);
6744
6745         ret = ext4_check_opt_consistency(fc, sb);
6746         if (ret < 0)
6747                 return ret;
6748
6749         ret = __ext4_remount(fc, sb);
6750         if (ret < 0)
6751                 return ret;
6752
6753         ext4_msg(sb, KERN_INFO, "re-mounted %pU %s. Quota mode: %s.",
6754                  &sb->s_uuid, sb_rdonly(sb) ? "ro" : "r/w",
6755                  ext4_quota_mode(sb));
6756
6757         return 0;
6758 }
6759
6760 #ifdef CONFIG_QUOTA
6761 static int ext4_statfs_project(struct super_block *sb,
6762                                kprojid_t projid, struct kstatfs *buf)
6763 {
6764         struct kqid qid;
6765         struct dquot *dquot;
6766         u64 limit;
6767         u64 curblock;
6768
6769         qid = make_kqid_projid(projid);
6770         dquot = dqget(sb, qid);
6771         if (IS_ERR(dquot))
6772                 return PTR_ERR(dquot);
6773         spin_lock(&dquot->dq_dqb_lock);
6774
6775         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6776                              dquot->dq_dqb.dqb_bhardlimit);
6777         limit >>= sb->s_blocksize_bits;
6778
6779         if (limit && buf->f_blocks > limit) {
6780                 curblock = (dquot->dq_dqb.dqb_curspace +
6781                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6782                 buf->f_blocks = limit;
6783                 buf->f_bfree = buf->f_bavail =
6784                         (buf->f_blocks > curblock) ?
6785                          (buf->f_blocks - curblock) : 0;
6786         }
6787
6788         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6789                              dquot->dq_dqb.dqb_ihardlimit);
6790         if (limit && buf->f_files > limit) {
6791                 buf->f_files = limit;
6792                 buf->f_ffree =
6793                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6794                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6795         }
6796
6797         spin_unlock(&dquot->dq_dqb_lock);
6798         dqput(dquot);
6799         return 0;
6800 }
6801 #endif
6802
6803 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6804 {
6805         struct super_block *sb = dentry->d_sb;
6806         struct ext4_sb_info *sbi = EXT4_SB(sb);
6807         struct ext4_super_block *es = sbi->s_es;
6808         ext4_fsblk_t overhead = 0, resv_blocks;
6809         s64 bfree;
6810         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6811
6812         if (!test_opt(sb, MINIX_DF))
6813                 overhead = sbi->s_overhead;
6814
6815         buf->f_type = EXT4_SUPER_MAGIC;
6816         buf->f_bsize = sb->s_blocksize;
6817         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6818         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6819                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6820         /* prevent underflow in case that few free space is available */
6821         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6822         buf->f_bavail = buf->f_bfree -
6823                         (ext4_r_blocks_count(es) + resv_blocks);
6824         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6825                 buf->f_bavail = 0;
6826         buf->f_files = le32_to_cpu(es->s_inodes_count);
6827         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6828         buf->f_namelen = EXT4_NAME_LEN;
6829         buf->f_fsid = uuid_to_fsid(es->s_uuid);
6830
6831 #ifdef CONFIG_QUOTA
6832         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6833             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6834                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6835 #endif
6836         return 0;
6837 }
6838
6839
6840 #ifdef CONFIG_QUOTA
6841
6842 /*
6843  * Helper functions so that transaction is started before we acquire dqio_sem
6844  * to keep correct lock ordering of transaction > dqio_sem
6845  */
6846 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6847 {
6848         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6849 }
6850
6851 static int ext4_write_dquot(struct dquot *dquot)
6852 {
6853         int ret, err;
6854         handle_t *handle;
6855         struct inode *inode;
6856
6857         inode = dquot_to_inode(dquot);
6858         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6859                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6860         if (IS_ERR(handle))
6861                 return PTR_ERR(handle);
6862         ret = dquot_commit(dquot);
6863         if (ret < 0)
6864                 ext4_error_err(dquot->dq_sb, -ret,
6865                                "Failed to commit dquot type %d",
6866                                dquot->dq_id.type);
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         if (ret < 0)
6884                 ext4_error_err(dquot->dq_sb, -ret,
6885                               "Failed to acquire dquot type %d",
6886                               dquot->dq_id.type);
6887         err = ext4_journal_stop(handle);
6888         if (!ret)
6889                 ret = err;
6890         return ret;
6891 }
6892
6893 static int ext4_release_dquot(struct dquot *dquot)
6894 {
6895         int ret, err;
6896         handle_t *handle;
6897
6898         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6899                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6900         if (IS_ERR(handle)) {
6901                 /* Release dquot anyway to avoid endless cycle in dqput() */
6902                 dquot_release(dquot);
6903                 return PTR_ERR(handle);
6904         }
6905         ret = dquot_release(dquot);
6906         if (ret < 0)
6907                 ext4_error_err(dquot->dq_sb, -ret,
6908                                "Failed to release dquot type %d",
6909                                dquot->dq_id.type);
6910         err = ext4_journal_stop(handle);
6911         if (!ret)
6912                 ret = err;
6913         return ret;
6914 }
6915
6916 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6917 {
6918         struct super_block *sb = dquot->dq_sb;
6919
6920         if (ext4_is_quota_journalled(sb)) {
6921                 dquot_mark_dquot_dirty(dquot);
6922                 return ext4_write_dquot(dquot);
6923         } else {
6924                 return dquot_mark_dquot_dirty(dquot);
6925         }
6926 }
6927
6928 static int ext4_write_info(struct super_block *sb, int type)
6929 {
6930         int ret, err;
6931         handle_t *handle;
6932
6933         /* Data block + inode block */
6934         handle = ext4_journal_start_sb(sb, EXT4_HT_QUOTA, 2);
6935         if (IS_ERR(handle))
6936                 return PTR_ERR(handle);
6937         ret = dquot_commit_info(sb, type);
6938         err = ext4_journal_stop(handle);
6939         if (!ret)
6940                 ret = err;
6941         return ret;
6942 }
6943
6944 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6945 {
6946         struct ext4_inode_info *ei = EXT4_I(inode);
6947
6948         /* The first argument of lockdep_set_subclass has to be
6949          * *exactly* the same as the argument to init_rwsem() --- in
6950          * this case, in init_once() --- or lockdep gets unhappy
6951          * because the name of the lock is set using the
6952          * stringification of the argument to init_rwsem().
6953          */
6954         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6955         lockdep_set_subclass(&ei->i_data_sem, subclass);
6956 }
6957
6958 /*
6959  * Standard function to be called on quota_on
6960  */
6961 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6962                          const struct path *path)
6963 {
6964         int err;
6965
6966         if (!test_opt(sb, QUOTA))
6967                 return -EINVAL;
6968
6969         /* Quotafile not on the same filesystem? */
6970         if (path->dentry->d_sb != sb)
6971                 return -EXDEV;
6972
6973         /* Quota already enabled for this file? */
6974         if (IS_NOQUOTA(d_inode(path->dentry)))
6975                 return -EBUSY;
6976
6977         /* Journaling quota? */
6978         if (EXT4_SB(sb)->s_qf_names[type]) {
6979                 /* Quotafile not in fs root? */
6980                 if (path->dentry->d_parent != sb->s_root)
6981                         ext4_msg(sb, KERN_WARNING,
6982                                 "Quota file not on filesystem root. "
6983                                 "Journaled quota will not work");
6984                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6985         } else {
6986                 /*
6987                  * Clear the flag just in case mount options changed since
6988                  * last time.
6989                  */
6990                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6991         }
6992
6993         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6994         err = dquot_quota_on(sb, type, format_id, path);
6995         if (!err) {
6996                 struct inode *inode = d_inode(path->dentry);
6997                 handle_t *handle;
6998
6999                 /*
7000                  * Set inode flags to prevent userspace from messing with quota
7001                  * files. If this fails, we return success anyway since quotas
7002                  * are already enabled and this is not a hard failure.
7003                  */
7004                 inode_lock(inode);
7005                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7006                 if (IS_ERR(handle))
7007                         goto unlock_inode;
7008                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
7009                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
7010                                 S_NOATIME | S_IMMUTABLE);
7011                 err = ext4_mark_inode_dirty(handle, inode);
7012                 ext4_journal_stop(handle);
7013         unlock_inode:
7014                 inode_unlock(inode);
7015                 if (err)
7016                         dquot_quota_off(sb, type);
7017         }
7018         if (err)
7019                 lockdep_set_quota_inode(path->dentry->d_inode,
7020                                              I_DATA_SEM_NORMAL);
7021         return err;
7022 }
7023
7024 static inline bool ext4_check_quota_inum(int type, unsigned long qf_inum)
7025 {
7026         switch (type) {
7027         case USRQUOTA:
7028                 return qf_inum == EXT4_USR_QUOTA_INO;
7029         case GRPQUOTA:
7030                 return qf_inum == EXT4_GRP_QUOTA_INO;
7031         case PRJQUOTA:
7032                 return qf_inum >= EXT4_GOOD_OLD_FIRST_INO;
7033         default:
7034                 BUG();
7035         }
7036 }
7037
7038 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
7039                              unsigned int flags)
7040 {
7041         int err;
7042         struct inode *qf_inode;
7043         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7044                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7045                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7046                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7047         };
7048
7049         BUG_ON(!ext4_has_feature_quota(sb));
7050
7051         if (!qf_inums[type])
7052                 return -EPERM;
7053
7054         if (!ext4_check_quota_inum(type, qf_inums[type])) {
7055                 ext4_error(sb, "Bad quota inum: %lu, type: %d",
7056                                 qf_inums[type], type);
7057                 return -EUCLEAN;
7058         }
7059
7060         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
7061         if (IS_ERR(qf_inode)) {
7062                 ext4_error(sb, "Bad quota inode: %lu, type: %d",
7063                                 qf_inums[type], type);
7064                 return PTR_ERR(qf_inode);
7065         }
7066
7067         /* Don't account quota for quota files to avoid recursion */
7068         qf_inode->i_flags |= S_NOQUOTA;
7069         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
7070         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
7071         if (err)
7072                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
7073         iput(qf_inode);
7074
7075         return err;
7076 }
7077
7078 /* Enable usage tracking for all quota types. */
7079 int ext4_enable_quotas(struct super_block *sb)
7080 {
7081         int type, err = 0;
7082         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7083                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7084                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7085                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7086         };
7087         bool quota_mopt[EXT4_MAXQUOTAS] = {
7088                 test_opt(sb, USRQUOTA),
7089                 test_opt(sb, GRPQUOTA),
7090                 test_opt(sb, PRJQUOTA),
7091         };
7092
7093         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
7094         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
7095                 if (qf_inums[type]) {
7096                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
7097                                 DQUOT_USAGE_ENABLED |
7098                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
7099                         if (err) {
7100                                 ext4_warning(sb,
7101                                         "Failed to enable quota tracking "
7102                                         "(type=%d, err=%d, ino=%lu). "
7103                                         "Please run e2fsck to fix.", type,
7104                                         err, qf_inums[type]);
7105
7106                                 ext4_quotas_off(sb, type);
7107                                 return err;
7108                         }
7109                 }
7110         }
7111         return 0;
7112 }
7113
7114 static int ext4_quota_off(struct super_block *sb, int type)
7115 {
7116         struct inode *inode = sb_dqopt(sb)->files[type];
7117         handle_t *handle;
7118         int err;
7119
7120         /* Force all delayed allocation blocks to be allocated.
7121          * Caller already holds s_umount sem */
7122         if (test_opt(sb, DELALLOC))
7123                 sync_filesystem(sb);
7124
7125         if (!inode || !igrab(inode))
7126                 goto out;
7127
7128         err = dquot_quota_off(sb, type);
7129         if (err || ext4_has_feature_quota(sb))
7130                 goto out_put;
7131         /*
7132          * When the filesystem was remounted read-only first, we cannot cleanup
7133          * inode flags here. Bad luck but people should be using QUOTA feature
7134          * these days anyway.
7135          */
7136         if (sb_rdonly(sb))
7137                 goto out_put;
7138
7139         inode_lock(inode);
7140         /*
7141          * Update modification times of quota files when userspace can
7142          * start looking at them. If we fail, we return success anyway since
7143          * this is not a hard failure and quotas are already disabled.
7144          */
7145         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7146         if (IS_ERR(handle)) {
7147                 err = PTR_ERR(handle);
7148                 goto out_unlock;
7149         }
7150         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
7151         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
7152         inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
7153         err = ext4_mark_inode_dirty(handle, inode);
7154         ext4_journal_stop(handle);
7155 out_unlock:
7156         inode_unlock(inode);
7157 out_put:
7158         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
7159         iput(inode);
7160         return err;
7161 out:
7162         return dquot_quota_off(sb, type);
7163 }
7164
7165 /* Read data from quotafile - avoid pagecache and such because we cannot afford
7166  * acquiring the locks... As quota files are never truncated and quota code
7167  * itself serializes the operations (and no one else should touch the files)
7168  * we don't have to be afraid of races */
7169 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
7170                                size_t len, loff_t off)
7171 {
7172         struct inode *inode = sb_dqopt(sb)->files[type];
7173         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7174         int offset = off & (sb->s_blocksize - 1);
7175         int tocopy;
7176         size_t toread;
7177         struct buffer_head *bh;
7178         loff_t i_size = i_size_read(inode);
7179
7180         if (off > i_size)
7181                 return 0;
7182         if (off+len > i_size)
7183                 len = i_size-off;
7184         toread = len;
7185         while (toread > 0) {
7186                 tocopy = min_t(unsigned long, sb->s_blocksize - offset, toread);
7187                 bh = ext4_bread(NULL, inode, blk, 0);
7188                 if (IS_ERR(bh))
7189                         return PTR_ERR(bh);
7190                 if (!bh)        /* A hole? */
7191                         memset(data, 0, tocopy);
7192                 else
7193                         memcpy(data, bh->b_data+offset, tocopy);
7194                 brelse(bh);
7195                 offset = 0;
7196                 toread -= tocopy;
7197                 data += tocopy;
7198                 blk++;
7199         }
7200         return len;
7201 }
7202
7203 /* Write to quotafile (we know the transaction is already started and has
7204  * enough credits) */
7205 static ssize_t ext4_quota_write(struct super_block *sb, int type,
7206                                 const char *data, size_t len, loff_t off)
7207 {
7208         struct inode *inode = sb_dqopt(sb)->files[type];
7209         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7210         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
7211         int retries = 0;
7212         struct buffer_head *bh;
7213         handle_t *handle = journal_current_handle();
7214
7215         if (!handle) {
7216                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7217                         " cancelled because transaction is not started",
7218                         (unsigned long long)off, (unsigned long long)len);
7219                 return -EIO;
7220         }
7221         /*
7222          * Since we account only one data block in transaction credits,
7223          * then it is impossible to cross a block boundary.
7224          */
7225         if (sb->s_blocksize - offset < len) {
7226                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7227                         " cancelled because not block aligned",
7228                         (unsigned long long)off, (unsigned long long)len);
7229                 return -EIO;
7230         }
7231
7232         do {
7233                 bh = ext4_bread(handle, inode, blk,
7234                                 EXT4_GET_BLOCKS_CREATE |
7235                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
7236         } while (PTR_ERR(bh) == -ENOSPC &&
7237                  ext4_should_retry_alloc(inode->i_sb, &retries));
7238         if (IS_ERR(bh))
7239                 return PTR_ERR(bh);
7240         if (!bh)
7241                 goto out;
7242         BUFFER_TRACE(bh, "get write access");
7243         err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
7244         if (err) {
7245                 brelse(bh);
7246                 return err;
7247         }
7248         lock_buffer(bh);
7249         memcpy(bh->b_data+offset, data, len);
7250         flush_dcache_page(bh->b_page);
7251         unlock_buffer(bh);
7252         err = ext4_handle_dirty_metadata(handle, NULL, bh);
7253         brelse(bh);
7254 out:
7255         if (inode->i_size < off + len) {
7256                 i_size_write(inode, off + len);
7257                 EXT4_I(inode)->i_disksize = inode->i_size;
7258                 err2 = ext4_mark_inode_dirty(handle, inode);
7259                 if (unlikely(err2 && !err))
7260                         err = err2;
7261         }
7262         return err ? err : len;
7263 }
7264 #endif
7265
7266 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
7267 static inline void register_as_ext2(void)
7268 {
7269         int err = register_filesystem(&ext2_fs_type);
7270         if (err)
7271                 printk(KERN_WARNING
7272                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7273 }
7274
7275 static inline void unregister_as_ext2(void)
7276 {
7277         unregister_filesystem(&ext2_fs_type);
7278 }
7279
7280 static inline int ext2_feature_set_ok(struct super_block *sb)
7281 {
7282         if (ext4_has_unknown_ext2_incompat_features(sb))
7283                 return 0;
7284         if (sb_rdonly(sb))
7285                 return 1;
7286         if (ext4_has_unknown_ext2_ro_compat_features(sb))
7287                 return 0;
7288         return 1;
7289 }
7290 #else
7291 static inline void register_as_ext2(void) { }
7292 static inline void unregister_as_ext2(void) { }
7293 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7294 #endif
7295
7296 static inline void register_as_ext3(void)
7297 {
7298         int err = register_filesystem(&ext3_fs_type);
7299         if (err)
7300                 printk(KERN_WARNING
7301                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7302 }
7303
7304 static inline void unregister_as_ext3(void)
7305 {
7306         unregister_filesystem(&ext3_fs_type);
7307 }
7308
7309 static inline int ext3_feature_set_ok(struct super_block *sb)
7310 {
7311         if (ext4_has_unknown_ext3_incompat_features(sb))
7312                 return 0;
7313         if (!ext4_has_feature_journal(sb))
7314                 return 0;
7315         if (sb_rdonly(sb))
7316                 return 1;
7317         if (ext4_has_unknown_ext3_ro_compat_features(sb))
7318                 return 0;
7319         return 1;
7320 }
7321
7322 static void ext4_kill_sb(struct super_block *sb)
7323 {
7324         struct ext4_sb_info *sbi = EXT4_SB(sb);
7325         struct file *bdev_file = sbi ? sbi->s_journal_bdev_file : NULL;
7326
7327         kill_block_super(sb);
7328
7329         if (bdev_file)
7330                 fput(bdev_file);
7331 }
7332
7333 static struct file_system_type ext4_fs_type = {
7334         .owner                  = THIS_MODULE,
7335         .name                   = "ext4",
7336         .init_fs_context        = ext4_init_fs_context,
7337         .parameters             = ext4_param_specs,
7338         .kill_sb                = ext4_kill_sb,
7339         .fs_flags               = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
7340 };
7341 MODULE_ALIAS_FS("ext4");
7342
7343 /* Shared across all ext4 file systems */
7344 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
7345
7346 static int __init ext4_init_fs(void)
7347 {
7348         int i, err;
7349
7350         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7351         ext4_li_info = NULL;
7352
7353         /* Build-time check for flags consistency */
7354         ext4_check_flag_values();
7355
7356         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
7357                 init_waitqueue_head(&ext4__ioend_wq[i]);
7358
7359         err = ext4_init_es();
7360         if (err)
7361                 return err;
7362
7363         err = ext4_init_pending();
7364         if (err)
7365                 goto out7;
7366
7367         err = ext4_init_post_read_processing();
7368         if (err)
7369                 goto out6;
7370
7371         err = ext4_init_pageio();
7372         if (err)
7373                 goto out5;
7374
7375         err = ext4_init_system_zone();
7376         if (err)
7377                 goto out4;
7378
7379         err = ext4_init_sysfs();
7380         if (err)
7381                 goto out3;
7382
7383         err = ext4_init_mballoc();
7384         if (err)
7385                 goto out2;
7386         err = init_inodecache();
7387         if (err)
7388                 goto out1;
7389
7390         err = ext4_fc_init_dentry_cache();
7391         if (err)
7392                 goto out05;
7393
7394         register_as_ext3();
7395         register_as_ext2();
7396         err = register_filesystem(&ext4_fs_type);
7397         if (err)
7398                 goto out;
7399
7400         return 0;
7401 out:
7402         unregister_as_ext2();
7403         unregister_as_ext3();
7404         ext4_fc_destroy_dentry_cache();
7405 out05:
7406         destroy_inodecache();
7407 out1:
7408         ext4_exit_mballoc();
7409 out2:
7410         ext4_exit_sysfs();
7411 out3:
7412         ext4_exit_system_zone();
7413 out4:
7414         ext4_exit_pageio();
7415 out5:
7416         ext4_exit_post_read_processing();
7417 out6:
7418         ext4_exit_pending();
7419 out7:
7420         ext4_exit_es();
7421
7422         return err;
7423 }
7424
7425 static void __exit ext4_exit_fs(void)
7426 {
7427         ext4_destroy_lazyinit_thread();
7428         unregister_as_ext2();
7429         unregister_as_ext3();
7430         unregister_filesystem(&ext4_fs_type);
7431         ext4_fc_destroy_dentry_cache();
7432         destroy_inodecache();
7433         ext4_exit_mballoc();
7434         ext4_exit_sysfs();
7435         ext4_exit_system_zone();
7436         ext4_exit_pageio();
7437         ext4_exit_post_read_processing();
7438         ext4_exit_es();
7439         ext4_exit_pending();
7440 }
7441
7442 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7443 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7444 MODULE_LICENSE("GPL");
7445 MODULE_SOFTDEP("pre: crc32c");
7446 module_init(ext4_init_fs)
7447 module_exit(ext4_exit_fs)