fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller (davem@caip.rutgers.edu), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/uaccess.h>
  43 #include <linux/iversion.h>
  44 #include <linux/unicode.h>
  45 #include <linux/part_stat.h>
  46 #include <linux/kthread.h>
  47 #include <linux/freezer.h>
  48 #include <linux/fsnotify.h>
  49 #include <linux/fs_context.h>
  50 #include <linux/fs_parser.h>
  51
  52 #include "ext4.h"
  53 #include "ext4_extents.h"       /* Needed for trace points definition */
  54 #include "ext4_jbd2.h"
  55 #include "xattr.h"
  56 #include "acl.h"
  57 #include "mballoc.h"
  58 #include "fsmap.h"
  59
  60 #define CREATE_TRACE_POINTS
  61 #include <trace/events/ext4.h>
  62
  63 static struct ext4_lazy_init *ext4_li_info;
  64 static DEFINE_MUTEX(ext4_li_mtx);
  65 static struct ratelimit_state ext4_mount_msg_ratelimit;
  66
  67 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  68                              unsigned long journal_devnum);
  69 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  70 static void ext4_update_super(struct super_block *sb);
  71 static int ext4_commit_super(struct super_block *sb);
  72 static int ext4_mark_recovery_complete(struct super_block *sb,
  73                                         struct ext4_super_block *es);
  74 static int ext4_clear_journal_err(struct super_block *sb,
  75                                   struct ext4_super_block *es);
  76 static int ext4_sync_fs(struct super_block *sb, int wait);
  77 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  78 static int ext4_unfreeze(struct super_block *sb);
  79 static int ext4_freeze(struct super_block *sb);
  80 static inline int ext2_feature_set_ok(struct super_block *sb);
  81 static inline int ext3_feature_set_ok(struct super_block *sb);
  82 static void ext4_destroy_lazyinit_thread(void);
  83 static void ext4_unregister_li_request(struct super_block *sb);
  84 static void ext4_clear_request_list(void);
  85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  86                                             unsigned int journal_inum);
  87 static int ext4_validate_options(struct fs_context *fc);
  88 static int ext4_check_opt_consistency(struct fs_context *fc,
  89                                       struct super_block *sb);
  90 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb);
  91 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param);
  92 static int ext4_get_tree(struct fs_context *fc);
  93 static int ext4_reconfigure(struct fs_context *fc);
  94 static void ext4_fc_free(struct fs_context *fc);
  95 static int ext4_init_fs_context(struct fs_context *fc);
  96 static void ext4_kill_sb(struct super_block *sb);
  97 static const struct fs_parameter_spec ext4_param_specs[];
  98
  99 /*
 100  * Lock ordering
 101  *
 102  * page fault path:
 103  * mmap_lock -> sb_start_pagefault -> invalidate_lock (r) -> transaction start
 104  *   -> page lock -> i_data_sem (rw)
 105  *
 106  * buffered write path:
 107  * sb_start_write -> i_mutex -> mmap_lock
 108  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 109  *   i_data_sem (rw)
 110  *
 111  * truncate:
 112  * sb_start_write -> i_mutex -> invalidate_lock (w) -> i_mmap_rwsem (w) ->
 113  *   page lock
 114  * sb_start_write -> i_mutex -> invalidate_lock (w) -> transaction start ->
 115  *   i_data_sem (rw)
 116  *
 117  * direct IO:
 118  * sb_start_write -> i_mutex -> mmap_lock
 119  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 120  *
 121  * writepages:
 122  * transaction start -> page lock(s) -> i_data_sem (rw)
 123  */
 124
 125 static const struct fs_context_operations ext4_context_ops = {
 126         .parse_param    = ext4_parse_param,
 127         .get_tree       = ext4_get_tree,
 128         .reconfigure    = ext4_reconfigure,
 129         .free           = ext4_fc_free,
 130 };
 131
 132
 133 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 134 static struct file_system_type ext2_fs_type = {
 135         .owner                  = THIS_MODULE,
 136         .name                   = "ext2",
 137         .init_fs_context        = ext4_init_fs_context,
 138         .parameters             = ext4_param_specs,
 139         .kill_sb                = ext4_kill_sb,
 140         .fs_flags               = FS_REQUIRES_DEV,
 141 };
 142 MODULE_ALIAS_FS("ext2");
 143 MODULE_ALIAS("ext2");
 144 #define IS_EXT2_SB(sb) ((sb)->s_type == &ext2_fs_type)
 145 #else
 146 #define IS_EXT2_SB(sb) (0)
 147 #endif
 148
 149
 150 static struct file_system_type ext3_fs_type = {
 151         .owner                  = THIS_MODULE,
 152         .name                   = "ext3",
 153         .init_fs_context        = ext4_init_fs_context,
 154         .parameters             = ext4_param_specs,
 155         .kill_sb                = ext4_kill_sb,
 156         .fs_flags               = FS_REQUIRES_DEV,
 157 };
 158 MODULE_ALIAS_FS("ext3");
 159 MODULE_ALIAS("ext3");
 160 #define IS_EXT3_SB(sb) ((sb)->s_type == &ext3_fs_type)
 161
 162
 163 static inline void __ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
 164                                   bh_end_io_t *end_io)
 165 {
 166         /*
 167          * buffer's verified bit is no longer valid after reading from
 168          * disk again due to write out error, clear it to make sure we
 169          * recheck the buffer contents.
 170          */
 171         clear_buffer_verified(bh);
 172
 173         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
 174         get_bh(bh);
 175         submit_bh(REQ_OP_READ | op_flags, bh);
 176 }
 177
 178 void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
 179                          bh_end_io_t *end_io)
 180 {
 181         BUG_ON(!buffer_locked(bh));
 182
 183         if (ext4_buffer_uptodate(bh)) {
 184                 unlock_buffer(bh);
 185                 return;
 186         }
 187         __ext4_read_bh(bh, op_flags, end_io);
 188 }
 189
 190 int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags, bh_end_io_t *end_io)
 191 {
 192         BUG_ON(!buffer_locked(bh));
 193
 194         if (ext4_buffer_uptodate(bh)) {
 195                 unlock_buffer(bh);
 196                 return 0;
 197         }
 198
 199         __ext4_read_bh(bh, op_flags, end_io);
 200
 201         wait_on_buffer(bh);
 202         if (buffer_uptodate(bh))
 203                 return 0;
 204         return -EIO;
 205 }
 206
 207 int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait)
 208 {
 209         lock_buffer(bh);
 210         if (!wait) {
 211                 ext4_read_bh_nowait(bh, op_flags, NULL);
 212                 return 0;
 213         }
 214         return ext4_read_bh(bh, op_flags, NULL);
 215 }
 216
 217 /*
 218  * This works like __bread_gfp() except it uses ERR_PTR for error
 219  * returns.  Currently with sb_bread it's impossible to distinguish
 220  * between ENOMEM and EIO situations (since both result in a NULL
 221  * return.
 222  */
 223 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 224                                                sector_t block,
 225                                                blk_opf_t op_flags, gfp_t gfp)
 226 {
 227         struct buffer_head *bh;
 228         int ret;
 229
 230         bh = sb_getblk_gfp(sb, block, gfp);
 231         if (bh == NULL)
 232                 return ERR_PTR(-ENOMEM);
 233         if (ext4_buffer_uptodate(bh))
 234                 return bh;
 235
 236         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
 237         if (ret) {
 238                 put_bh(bh);
 239                 return ERR_PTR(ret);
 240         }
 241         return bh;
 242 }
 243
 244 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 245                                    blk_opf_t op_flags)
 246 {
 247         gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_inode->i_mapping,
 248                         ~__GFP_FS) | __GFP_MOVABLE;
 249
 250         return __ext4_sb_bread_gfp(sb, block, op_flags, gfp);
 251 }
 252
 253 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 254                                             sector_t block)
 255 {
 256         gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_inode->i_mapping,
 257                         ~__GFP_FS);
 258
 259         return __ext4_sb_bread_gfp(sb, block, 0, gfp);
 260 }
 261
 262 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
 263 {
 264         struct buffer_head *bh = bdev_getblk(sb->s_bdev, block,
 265                         sb->s_blocksize, GFP_NOWAIT | __GFP_NOWARN);
 266
 267         if (likely(bh)) {
 268                 if (trylock_buffer(bh))
 269                         ext4_read_bh_nowait(bh, REQ_RAHEAD, NULL);
 270                 brelse(bh);
 271         }
 272 }
 273
 274 static int ext4_verify_csum_type(struct super_block *sb,
 275                                  struct ext4_super_block *es)
 276 {
 277         if (!ext4_has_feature_metadata_csum(sb))
 278                 return 1;
 279
 280         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 281 }
 282
 283 __le32 ext4_superblock_csum(struct super_block *sb,
 284                             struct ext4_super_block *es)
 285 {
 286         struct ext4_sb_info *sbi = EXT4_SB(sb);
 287         int offset = offsetof(struct ext4_super_block, s_checksum);
 288         __u32 csum;
 289
 290         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 291
 292         return cpu_to_le32(csum);
 293 }
 294
 295 static int ext4_superblock_csum_verify(struct super_block *sb,
 296                                        struct ext4_super_block *es)
 297 {
 298         if (!ext4_has_metadata_csum(sb))
 299                 return 1;
 300
 301         return es->s_checksum == ext4_superblock_csum(sb, es);
 302 }
 303
 304 void ext4_superblock_csum_set(struct super_block *sb)
 305 {
 306         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 307
 308         if (!ext4_has_metadata_csum(sb))
 309                 return;
 310
 311         es->s_checksum = ext4_superblock_csum(sb, es);
 312 }
 313
 314 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 315                                struct ext4_group_desc *bg)
 316 {
 317         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 318                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 319                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 320 }
 321
 322 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 323                                struct ext4_group_desc *bg)
 324 {
 325         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 326                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 327                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 328 }
 329
 330 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 331                               struct ext4_group_desc *bg)
 332 {
 333         return le32_to_cpu(bg->bg_inode_table_lo) |
 334                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 335                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 336 }
 337
 338 __u32 ext4_free_group_clusters(struct super_block *sb,
 339                                struct ext4_group_desc *bg)
 340 {
 341         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 342                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 343                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 344 }
 345
 346 __u32 ext4_free_inodes_count(struct super_block *sb,
 347                               struct ext4_group_desc *bg)
 348 {
 349         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 350                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 351                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 352 }
 353
 354 __u32 ext4_used_dirs_count(struct super_block *sb,
 355                               struct ext4_group_desc *bg)
 356 {
 357         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 358                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 359                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 360 }
 361
 362 __u32 ext4_itable_unused_count(struct super_block *sb,
 363                               struct ext4_group_desc *bg)
 364 {
 365         return le16_to_cpu(bg->bg_itable_unused_lo) |
 366                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 367                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 368 }
 369
 370 void ext4_block_bitmap_set(struct super_block *sb,
 371                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 372 {
 373         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 374         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 375                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 376 }
 377
 378 void ext4_inode_bitmap_set(struct super_block *sb,
 379                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 380 {
 381         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 382         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 383                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 384 }
 385
 386 void ext4_inode_table_set(struct super_block *sb,
 387                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 388 {
 389         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 390         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 391                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 392 }
 393
 394 void ext4_free_group_clusters_set(struct super_block *sb,
 395                                   struct ext4_group_desc *bg, __u32 count)
 396 {
 397         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 398         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 399                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 400 }
 401
 402 void ext4_free_inodes_set(struct super_block *sb,
 403                           struct ext4_group_desc *bg, __u32 count)
 404 {
 405         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 406         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 407                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 408 }
 409
 410 void ext4_used_dirs_set(struct super_block *sb,
 411                           struct ext4_group_desc *bg, __u32 count)
 412 {
 413         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 414         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 415                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 416 }
 417
 418 void ext4_itable_unused_set(struct super_block *sb,
 419                           struct ext4_group_desc *bg, __u32 count)
 420 {
 421         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 422         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 423                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 424 }
 425
 426 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi, time64_t now)
 427 {
 428         now = clamp_val(now, 0, (1ull << 40) - 1);
 429
 430         *lo = cpu_to_le32(lower_32_bits(now));
 431         *hi = upper_32_bits(now);
 432 }
 433
 434 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 435 {
 436         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 437 }
 438 #define ext4_update_tstamp(es, tstamp) \
 439         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi, \
 440                              ktime_get_real_seconds())
 441 #define ext4_get_tstamp(es, tstamp) \
 442         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 443
 444 #define EXT4_SB_REFRESH_INTERVAL_SEC (3600) /* seconds (1 hour) */
 445 #define EXT4_SB_REFRESH_INTERVAL_KB (16384) /* kilobytes (16MB) */
 446
 447 /*
 448  * The ext4_maybe_update_superblock() function checks and updates the
 449  * superblock if needed.
 450  *
 451  * This function is designed to update the on-disk superblock only under
 452  * certain conditions to prevent excessive disk writes and unnecessary
 453  * waking of the disk from sleep. The superblock will be updated if:
 454  * 1. More than an hour has passed since the last superblock update, and
 455  * 2. More than 16MB have been written since the last superblock update.
 456  *
 457  * @sb: The superblock
 458  */
 459 static void ext4_maybe_update_superblock(struct super_block *sb)
 460 {
 461         struct ext4_sb_info *sbi = EXT4_SB(sb);
 462         struct ext4_super_block *es = sbi->s_es;
 463         journal_t *journal = sbi->s_journal;
 464         time64_t now;
 465         __u64 last_update;
 466         __u64 lifetime_write_kbytes;
 467         __u64 diff_size;
 468
 469         if (sb_rdonly(sb) || !(sb->s_flags & SB_ACTIVE) ||
 470             !journal || (journal->j_flags & JBD2_UNMOUNT))
 471                 return;
 472
 473         now = ktime_get_real_seconds();
 474         last_update = ext4_get_tstamp(es, s_wtime);
 475
 476         if (likely(now - last_update < EXT4_SB_REFRESH_INTERVAL_SEC))
 477                 return;
 478
 479         lifetime_write_kbytes = sbi->s_kbytes_written +
 480                 ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
 481                   sbi->s_sectors_written_start) >> 1);
 482
 483         /* Get the number of kilobytes not written to disk to account
 484          * for statistics and compare with a multiple of 16 MB. This
 485          * is used to determine when the next superblock commit should
 486          * occur (i.e. not more often than once per 16MB if there was
 487          * less written in an hour).
 488          */
 489         diff_size = lifetime_write_kbytes - le64_to_cpu(es->s_kbytes_written);
 490
 491         if (diff_size > EXT4_SB_REFRESH_INTERVAL_KB)
 492                 schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
 493 }
 494
 495 /*
 496  * The del_gendisk() function uninitializes the disk-specific data
 497  * structures, including the bdi structure, without telling anyone
 498  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 499  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 500  * This is a kludge to prevent these oops until we can put in a proper
 501  * hook in del_gendisk() to inform the VFS and file system layers.
 502  */
 503 static int block_device_ejected(struct super_block *sb)
 504 {
 505         struct inode *bd_inode = sb->s_bdev->bd_inode;
 506         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 507
 508         return bdi->dev == NULL;
 509 }
 510
 511 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 512 {
 513         struct super_block              *sb = journal->j_private;
 514         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 515         int                             error = is_journal_aborted(journal);
 516         struct ext4_journal_cb_entry    *jce;
 517
 518         BUG_ON(txn->t_state == T_FINISHED);
 519
 520         ext4_process_freed_data(sb, txn->t_tid);
 521         ext4_maybe_update_superblock(sb);
 522
 523         spin_lock(&sbi->s_md_lock);
 524         while (!list_empty(&txn->t_private_list)) {
 525                 jce = list_entry(txn->t_private_list.next,
 526                                  struct ext4_journal_cb_entry, jce_list);
 527                 list_del_init(&jce->jce_list);
 528                 spin_unlock(&sbi->s_md_lock);
 529                 jce->jce_func(sb, jce, error);
 530                 spin_lock(&sbi->s_md_lock);
 531         }
 532         spin_unlock(&sbi->s_md_lock);
 533 }
 534
 535 /*
 536  * This writepage callback for write_cache_pages()
 537  * takes care of a few cases after page cleaning.
 538  *
 539  * write_cache_pages() already checks for dirty pages
 540  * and calls clear_page_dirty_for_io(), which we want,
 541  * to write protect the pages.
 542  *
 543  * However, we may have to redirty a page (see below.)
 544  */
 545 static int ext4_journalled_writepage_callback(struct folio *folio,
 546                                               struct writeback_control *wbc,
 547                                               void *data)
 548 {
 549         transaction_t *transaction = (transaction_t *) data;
 550         struct buffer_head *bh, *head;
 551         struct journal_head *jh;
 552
 553         bh = head = folio_buffers(folio);
 554         do {
 555                 /*
 556                  * We have to redirty a page in these cases:
 557                  * 1) If buffer is dirty, it means the page was dirty because it
 558                  * contains a buffer that needs checkpointing. So the dirty bit
 559                  * needs to be preserved so that checkpointing writes the buffer
 560                  * properly.
 561                  * 2) If buffer is not part of the committing transaction
 562                  * (we may have just accidentally come across this buffer because
 563                  * inode range tracking is not exact) or if the currently running
 564                  * transaction already contains this buffer as well, dirty bit
 565                  * needs to be preserved so that the buffer gets writeprotected
 566                  * properly on running transaction's commit.
 567                  */
 568                 jh = bh2jh(bh);
 569                 if (buffer_dirty(bh) ||
 570                     (jh && (jh->b_transaction != transaction ||
 571                             jh->b_next_transaction))) {
 572                         folio_redirty_for_writepage(wbc, folio);
 573                         goto out;
 574                 }
 575         } while ((bh = bh->b_this_page) != head);
 576
 577 out:
 578         return AOP_WRITEPAGE_ACTIVATE;
 579 }
 580
 581 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
 582 {
 583         struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
 584         struct writeback_control wbc = {
 585                 .sync_mode =  WB_SYNC_ALL,
 586                 .nr_to_write = LONG_MAX,
 587                 .range_start = jinode->i_dirty_start,
 588                 .range_end = jinode->i_dirty_end,
 589         };
 590
 591         return write_cache_pages(mapping, &wbc,
 592                                  ext4_journalled_writepage_callback,
 593                                  jinode->i_transaction);
 594 }
 595
 596 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
 597 {
 598         int ret;
 599
 600         if (ext4_should_journal_data(jinode->i_vfs_inode))
 601                 ret = ext4_journalled_submit_inode_data_buffers(jinode);
 602         else
 603                 ret = ext4_normal_submit_inode_data_buffers(jinode);
 604         return ret;
 605 }
 606
 607 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
 608 {
 609         int ret = 0;
 610
 611         if (!ext4_should_journal_data(jinode->i_vfs_inode))
 612                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
 613
 614         return ret;
 615 }
 616
 617 static bool system_going_down(void)
 618 {
 619         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 620                 || system_state == SYSTEM_RESTART;
 621 }
 622
 623 struct ext4_err_translation {
 624         int code;
 625         int errno;
 626 };
 627
 628 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
 629
 630 static struct ext4_err_translation err_translation[] = {
 631         EXT4_ERR_TRANSLATE(EIO),
 632         EXT4_ERR_TRANSLATE(ENOMEM),
 633         EXT4_ERR_TRANSLATE(EFSBADCRC),
 634         EXT4_ERR_TRANSLATE(EFSCORRUPTED),
 635         EXT4_ERR_TRANSLATE(ENOSPC),
 636         EXT4_ERR_TRANSLATE(ENOKEY),
 637         EXT4_ERR_TRANSLATE(EROFS),
 638         EXT4_ERR_TRANSLATE(EFBIG),
 639         EXT4_ERR_TRANSLATE(EEXIST),
 640         EXT4_ERR_TRANSLATE(ERANGE),
 641         EXT4_ERR_TRANSLATE(EOVERFLOW),
 642         EXT4_ERR_TRANSLATE(EBUSY),
 643         EXT4_ERR_TRANSLATE(ENOTDIR),
 644         EXT4_ERR_TRANSLATE(ENOTEMPTY),
 645         EXT4_ERR_TRANSLATE(ESHUTDOWN),
 646         EXT4_ERR_TRANSLATE(EFAULT),
 647 };
 648
 649 static int ext4_errno_to_code(int errno)
 650 {
 651         int i;
 652
 653         for (i = 0; i < ARRAY_SIZE(err_translation); i++)
 654                 if (err_translation[i].errno == errno)
 655                         return err_translation[i].code;
 656         return EXT4_ERR_UNKNOWN;
 657 }
 658
 659 static void save_error_info(struct super_block *sb, int error,
 660                             __u32 ino, __u64 block,
 661                             const char *func, unsigned int line)
 662 {
 663         struct ext4_sb_info *sbi = EXT4_SB(sb);
 664
 665         /* We default to EFSCORRUPTED error... */
 666         if (error == 0)
 667                 error = EFSCORRUPTED;
 668
 669         spin_lock(&sbi->s_error_lock);
 670         sbi->s_add_error_count++;
 671         sbi->s_last_error_code = error;
 672         sbi->s_last_error_line = line;
 673         sbi->s_last_error_ino = ino;
 674         sbi->s_last_error_block = block;
 675         sbi->s_last_error_func = func;
 676         sbi->s_last_error_time = ktime_get_real_seconds();
 677         if (!sbi->s_first_error_time) {
 678                 sbi->s_first_error_code = error;
 679                 sbi->s_first_error_line = line;
 680                 sbi->s_first_error_ino = ino;
 681                 sbi->s_first_error_block = block;
 682                 sbi->s_first_error_func = func;
 683                 sbi->s_first_error_time = sbi->s_last_error_time;
 684         }
 685         spin_unlock(&sbi->s_error_lock);
 686 }
 687
 688 /* Deal with the reporting of failure conditions on a filesystem such as
 689  * inconsistencies detected or read IO failures.
 690  *
 691  * On ext2, we can store the error state of the filesystem in the
 692  * superblock.  That is not possible on ext4, because we may have other
 693  * write ordering constraints on the superblock which prevent us from
 694  * writing it out straight away; and given that the journal is about to
 695  * be aborted, we can't rely on the current, or future, transactions to
 696  * write out the superblock safely.
 697  *
 698  * We'll just use the jbd2_journal_abort() error code to record an error in
 699  * the journal instead.  On recovery, the journal will complain about
 700  * that error until we've noted it down and cleared it.
 701  *
 702  * If force_ro is set, we unconditionally force the filesystem into an
 703  * ABORT|READONLY state, unless the error response on the fs has been set to
 704  * panic in which case we take the easy way out and panic immediately. This is
 705  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
 706  * at a critical moment in log management.
 707  */
 708 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
 709                               __u32 ino, __u64 block,
 710                               const char *func, unsigned int line)
 711 {
 712         journal_t *journal = EXT4_SB(sb)->s_journal;
 713         bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
 714
 715         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 716         if (test_opt(sb, WARN_ON_ERROR))
 717                 WARN_ON_ONCE(1);
 718
 719         if (!continue_fs && !sb_rdonly(sb)) {
 720                 set_bit(EXT4_FLAGS_SHUTDOWN, &EXT4_SB(sb)->s_ext4_flags);
 721                 if (journal)
 722                         jbd2_journal_abort(journal, -EIO);
 723         }
 724
 725         if (!bdev_read_only(sb->s_bdev)) {
 726                 save_error_info(sb, error, ino, block, func, line);
 727                 /*
 728                  * In case the fs should keep running, we need to writeout
 729                  * superblock through the journal. Due to lock ordering
 730                  * constraints, it may not be safe to do it right here so we
 731                  * defer superblock flushing to a workqueue.
 732                  */
 733                 if (continue_fs && journal)
 734                         schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
 735                 else
 736                         ext4_commit_super(sb);
 737         }
 738
 739         /*
 740          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 741          * could panic during 'reboot -f' as the underlying device got already
 742          * disabled.
 743          */
 744         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 745                 panic("EXT4-fs (device %s): panic forced after error\n",
 746                         sb->s_id);
 747         }
 748
 749         if (sb_rdonly(sb) || continue_fs)
 750                 return;
 751
 752         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 753         /*
 754          * Make sure updated value of ->s_mount_flags will be visible before
 755          * ->s_flags update
 756          */
 757         smp_wmb();
 758         sb->s_flags |= SB_RDONLY;
 759 }
 760
 761 static void update_super_work(struct work_struct *work)
 762 {
 763         struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
 764                                                 s_sb_upd_work);
 765         journal_t *journal = sbi->s_journal;
 766         handle_t *handle;
 767
 768         /*
 769          * If the journal is still running, we have to write out superblock
 770          * through the journal to avoid collisions of other journalled sb
 771          * updates.
 772          *
 773          * We use directly jbd2 functions here to avoid recursing back into
 774          * ext4 error handling code during handling of previous errors.
 775          */
 776         if (!sb_rdonly(sbi->s_sb) && journal) {
 777                 struct buffer_head *sbh = sbi->s_sbh;
 778                 bool call_notify_err = false;
 779
 780                 handle = jbd2_journal_start(journal, 1);
 781                 if (IS_ERR(handle))
 782                         goto write_directly;
 783                 if (jbd2_journal_get_write_access(handle, sbh)) {
 784                         jbd2_journal_stop(handle);
 785                         goto write_directly;
 786                 }
 787
 788                 if (sbi->s_add_error_count > 0)
 789                         call_notify_err = true;
 790
 791                 ext4_update_super(sbi->s_sb);
 792                 if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
 793                         ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
 794                                  "superblock detected");
 795                         clear_buffer_write_io_error(sbh);
 796                         set_buffer_uptodate(sbh);
 797                 }
 798
 799                 if (jbd2_journal_dirty_metadata(handle, sbh)) {
 800                         jbd2_journal_stop(handle);
 801                         goto write_directly;
 802                 }
 803                 jbd2_journal_stop(handle);
 804
 805                 if (call_notify_err)
 806                         ext4_notify_error_sysfs(sbi);
 807
 808                 return;
 809         }
 810 write_directly:
 811         /*
 812          * Write through journal failed. Write sb directly to get error info
 813          * out and hope for the best.
 814          */
 815         ext4_commit_super(sbi->s_sb);
 816         ext4_notify_error_sysfs(sbi);
 817 }
 818
 819 #define ext4_error_ratelimit(sb)                                        \
 820                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 821                              "EXT4-fs error")
 822
 823 void __ext4_error(struct super_block *sb, const char *function,
 824                   unsigned int line, bool force_ro, int error, __u64 block,
 825                   const char *fmt, ...)
 826 {
 827         struct va_format vaf;
 828         va_list args;
 829
 830         if (unlikely(ext4_forced_shutdown(sb)))
 831                 return;
 832
 833         trace_ext4_error(sb, function, line);
 834         if (ext4_error_ratelimit(sb)) {
 835                 va_start(args, fmt);
 836                 vaf.fmt = fmt;
 837                 vaf.va = &args;
 838                 printk(KERN_CRIT
 839                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 840                        sb->s_id, function, line, current->comm, &vaf);
 841                 va_end(args);
 842         }
 843         fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
 844
 845         ext4_handle_error(sb, force_ro, error, 0, block, function, line);
 846 }
 847
 848 void __ext4_error_inode(struct inode *inode, const char *function,
 849                         unsigned int line, ext4_fsblk_t block, int error,
 850                         const char *fmt, ...)
 851 {
 852         va_list args;
 853         struct va_format vaf;
 854
 855         if (unlikely(ext4_forced_shutdown(inode->i_sb)))
 856                 return;
 857
 858         trace_ext4_error(inode->i_sb, function, line);
 859         if (ext4_error_ratelimit(inode->i_sb)) {
 860                 va_start(args, fmt);
 861                 vaf.fmt = fmt;
 862                 vaf.va = &args;
 863                 if (block)
 864                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 865                                "inode #%lu: block %llu: comm %s: %pV\n",
 866                                inode->i_sb->s_id, function, line, inode->i_ino,
 867                                block, current->comm, &vaf);
 868                 else
 869                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 870                                "inode #%lu: comm %s: %pV\n",
 871                                inode->i_sb->s_id, function, line, inode->i_ino,
 872                                current->comm, &vaf);
 873                 va_end(args);
 874         }
 875         fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
 876
 877         ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
 878                           function, line);
 879 }
 880
 881 void __ext4_error_file(struct file *file, const char *function,
 882                        unsigned int line, ext4_fsblk_t block,
 883                        const char *fmt, ...)
 884 {
 885         va_list args;
 886         struct va_format vaf;
 887         struct inode *inode = file_inode(file);
 888         char pathname[80], *path;
 889
 890         if (unlikely(ext4_forced_shutdown(inode->i_sb)))
 891                 return;
 892
 893         trace_ext4_error(inode->i_sb, function, line);
 894         if (ext4_error_ratelimit(inode->i_sb)) {
 895                 path = file_path(file, pathname, sizeof(pathname));
 896                 if (IS_ERR(path))
 897                         path = "(unknown)";
 898                 va_start(args, fmt);
 899                 vaf.fmt = fmt;
 900                 vaf.va = &args;
 901                 if (block)
 902                         printk(KERN_CRIT
 903                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 904                                "block %llu: comm %s: path %s: %pV\n",
 905                                inode->i_sb->s_id, function, line, inode->i_ino,
 906                                block, current->comm, path, &vaf);
 907                 else
 908                         printk(KERN_CRIT
 909                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 910                                "comm %s: path %s: %pV\n",
 911                                inode->i_sb->s_id, function, line, inode->i_ino,
 912                                current->comm, path, &vaf);
 913                 va_end(args);
 914         }
 915         fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
 916
 917         ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
 918                           function, line);
 919 }
 920
 921 const char *ext4_decode_error(struct super_block *sb, int errno,
 922                               char nbuf[16])
 923 {
 924         char *errstr = NULL;
 925
 926         switch (errno) {
 927         case -EFSCORRUPTED:
 928                 errstr = "Corrupt filesystem";
 929                 break;
 930         case -EFSBADCRC:
 931                 errstr = "Filesystem failed CRC";
 932                 break;
 933         case -EIO:
 934                 errstr = "IO failure";
 935                 break;
 936         case -ENOMEM:
 937                 errstr = "Out of memory";
 938                 break;
 939         case -EROFS:
 940                 if (!sb || (EXT4_SB(sb)->s_journal &&
 941                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 942                         errstr = "Journal has aborted";
 943                 else
 944                         errstr = "Readonly filesystem";
 945                 break;
 946         default:
 947                 /* If the caller passed in an extra buffer for unknown
 948                  * errors, textualise them now.  Else we just return
 949                  * NULL. */
 950                 if (nbuf) {
 951                         /* Check for truncated error codes... */
 952                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 953                                 errstr = nbuf;
 954                 }
 955                 break;
 956         }
 957
 958         return errstr;
 959 }
 960
 961 /* __ext4_std_error decodes expected errors from journaling functions
 962  * automatically and invokes the appropriate error response.  */
 963
 964 void __ext4_std_error(struct super_block *sb, const char *function,
 965                       unsigned int line, int errno)
 966 {
 967         char nbuf[16];
 968         const char *errstr;
 969
 970         if (unlikely(ext4_forced_shutdown(sb)))
 971                 return;
 972
 973         /* Special case: if the error is EROFS, and we're not already
 974          * inside a transaction, then there's really no point in logging
 975          * an error. */
 976         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 977                 return;
 978
 979         if (ext4_error_ratelimit(sb)) {
 980                 errstr = ext4_decode_error(sb, errno, nbuf);
 981                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 982                        sb->s_id, function, line, errstr);
 983         }
 984         fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
 985
 986         ext4_handle_error(sb, false, -errno, 0, 0, function, line);
 987 }
 988
 989 void __ext4_msg(struct super_block *sb,
 990                 const char *prefix, const char *fmt, ...)
 991 {
 992         struct va_format vaf;
 993         va_list args;
 994
 995         if (sb) {
 996                 atomic_inc(&EXT4_SB(sb)->s_msg_count);
 997                 if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state),
 998                                   "EXT4-fs"))
 999                         return;
1000         }
1001
1002         va_start(args, fmt);
1003         vaf.fmt = fmt;
1004         vaf.va = &args;
1005         if (sb)
1006                 printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
1007         else
1008                 printk("%sEXT4-fs: %pV\n", prefix, &vaf);
1009         va_end(args);
1010 }
1011
1012 static int ext4_warning_ratelimit(struct super_block *sb)
1013 {
1014         atomic_inc(&EXT4_SB(sb)->s_warning_count);
1015         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
1016                             "EXT4-fs warning");
1017 }
1018
1019 void __ext4_warning(struct super_block *sb, const char *function,
1020                     unsigned int line, const char *fmt, ...)
1021 {
1022         struct va_format vaf;
1023         va_list args;
1024
1025         if (!ext4_warning_ratelimit(sb))
1026                 return;
1027
1028         va_start(args, fmt);
1029         vaf.fmt = fmt;
1030         vaf.va = &args;
1031         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
1032                sb->s_id, function, line, &vaf);
1033         va_end(args);
1034 }
1035
1036 void __ext4_warning_inode(const struct inode *inode, const char *function,
1037                           unsigned int line, const char *fmt, ...)
1038 {
1039         struct va_format vaf;
1040         va_list args;
1041
1042         if (!ext4_warning_ratelimit(inode->i_sb))
1043                 return;
1044
1045         va_start(args, fmt);
1046         vaf.fmt = fmt;
1047         vaf.va = &args;
1048         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
1049                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
1050                function, line, inode->i_ino, current->comm, &vaf);
1051         va_end(args);
1052 }
1053
1054 void __ext4_grp_locked_error(const char *function, unsigned int line,
1055                              struct super_block *sb, ext4_group_t grp,
1056                              unsigned long ino, ext4_fsblk_t block,
1057                              const char *fmt, ...)
1058 __releases(bitlock)
1059 __acquires(bitlock)
1060 {
1061         struct va_format vaf;
1062         va_list args;
1063
1064         if (unlikely(ext4_forced_shutdown(sb)))
1065                 return;
1066
1067         trace_ext4_error(sb, function, line);
1068         if (ext4_error_ratelimit(sb)) {
1069                 va_start(args, fmt);
1070                 vaf.fmt = fmt;
1071                 vaf.va = &args;
1072                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1073                        sb->s_id, function, line, grp);
1074                 if (ino)
1075                         printk(KERN_CONT "inode %lu: ", ino);
1076                 if (block)
1077                         printk(KERN_CONT "block %llu:",
1078                                (unsigned long long) block);
1079                 printk(KERN_CONT "%pV\n", &vaf);
1080                 va_end(args);
1081         }
1082
1083         if (test_opt(sb, ERRORS_CONT)) {
1084                 if (test_opt(sb, WARN_ON_ERROR))
1085                         WARN_ON_ONCE(1);
1086                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
1087                 if (!bdev_read_only(sb->s_bdev)) {
1088                         save_error_info(sb, EFSCORRUPTED, ino, block, function,
1089                                         line);
1090                         schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
1091                 }
1092                 return;
1093         }
1094         ext4_unlock_group(sb, grp);
1095         ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1096         /*
1097          * We only get here in the ERRORS_RO case; relocking the group
1098          * may be dangerous, but nothing bad will happen since the
1099          * filesystem will have already been marked read/only and the
1100          * journal has been aborted.  We return 1 as a hint to callers
1101          * who might what to use the return value from
1102          * ext4_grp_locked_error() to distinguish between the
1103          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1104          * aggressively from the ext4 function in question, with a
1105          * more appropriate error code.
1106          */
1107         ext4_lock_group(sb, grp);
1108         return;
1109 }
1110
1111 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1112                                      ext4_group_t group,
1113                                      unsigned int flags)
1114 {
1115         struct ext4_sb_info *sbi = EXT4_SB(sb);
1116         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1117         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1118         int ret;
1119
1120         if (!grp || !gdp)
1121                 return;
1122         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1123                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1124                                             &grp->bb_state);
1125                 if (!ret)
1126                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1127                                            grp->bb_free);
1128         }
1129
1130         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1131                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1132                                             &grp->bb_state);
1133                 if (!ret && gdp) {
1134                         int count;
1135
1136                         count = ext4_free_inodes_count(sb, gdp);
1137                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1138                                            count);
1139                 }
1140         }
1141 }
1142
1143 void ext4_update_dynamic_rev(struct super_block *sb)
1144 {
1145         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1146
1147         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1148                 return;
1149
1150         ext4_warning(sb,
1151                      "updating to rev %d because of new feature flag, "
1152                      "running e2fsck is recommended",
1153                      EXT4_DYNAMIC_REV);
1154
1155         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1156         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1157         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1158         /* leave es->s_feature_*compat flags alone */
1159         /* es->s_uuid will be set by e2fsck if empty */
1160
1161         /*
1162          * The rest of the superblock fields should be zero, and if not it
1163          * means they are likely already in use, so leave them alone.  We
1164          * can leave it up to e2fsck to clean up any inconsistencies there.
1165          */
1166 }
1167
1168 static inline struct inode *orphan_list_entry(struct list_head *l)
1169 {
1170         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1171 }
1172
1173 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1174 {
1175         struct list_head *l;
1176
1177         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1178                  le32_to_cpu(sbi->s_es->s_last_orphan));
1179
1180         printk(KERN_ERR "sb_info orphan list:\n");
1181         list_for_each(l, &sbi->s_orphan) {
1182                 struct inode *inode = orphan_list_entry(l);
1183                 printk(KERN_ERR "  "
1184                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1185                        inode->i_sb->s_id, inode->i_ino, inode,
1186                        inode->i_mode, inode->i_nlink,
1187                        NEXT_ORPHAN(inode));
1188         }
1189 }
1190
1191 #ifdef CONFIG_QUOTA
1192 static int ext4_quota_off(struct super_block *sb, int type);
1193
1194 static inline void ext4_quotas_off(struct super_block *sb, int type)
1195 {
1196         BUG_ON(type > EXT4_MAXQUOTAS);
1197
1198         /* Use our quota_off function to clear inode flags etc. */
1199         for (type--; type >= 0; type--)
1200                 ext4_quota_off(sb, type);
1201 }
1202
1203 /*
1204  * This is a helper function which is used in the mount/remount
1205  * codepaths (which holds s_umount) to fetch the quota file name.
1206  */
1207 static inline char *get_qf_name(struct super_block *sb,
1208                                 struct ext4_sb_info *sbi,
1209                                 int type)
1210 {
1211         return rcu_dereference_protected(sbi->s_qf_names[type],
1212                                          lockdep_is_held(&sb->s_umount));
1213 }
1214 #else
1215 static inline void ext4_quotas_off(struct super_block *sb, int type)
1216 {
1217 }
1218 #endif
1219
1220 static int ext4_percpu_param_init(struct ext4_sb_info *sbi)
1221 {
1222         ext4_fsblk_t block;
1223         int err;
1224
1225         block = ext4_count_free_clusters(sbi->s_sb);
1226         ext4_free_blocks_count_set(sbi->s_es, EXT4_C2B(sbi, block));
1227         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
1228                                   GFP_KERNEL);
1229         if (!err) {
1230                 unsigned long freei = ext4_count_free_inodes(sbi->s_sb);
1231                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
1232                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
1233                                           GFP_KERNEL);
1234         }
1235         if (!err)
1236                 err = percpu_counter_init(&sbi->s_dirs_counter,
1237                                           ext4_count_dirs(sbi->s_sb), GFP_KERNEL);
1238         if (!err)
1239                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
1240                                           GFP_KERNEL);
1241         if (!err)
1242                 err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
1243                                           GFP_KERNEL);
1244         if (!err)
1245                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
1246
1247         if (err)
1248                 ext4_msg(sbi->s_sb, KERN_ERR, "insufficient memory");
1249
1250         return err;
1251 }
1252
1253 static void ext4_percpu_param_destroy(struct ext4_sb_info *sbi)
1254 {
1255         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1256         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1257         percpu_counter_destroy(&sbi->s_dirs_counter);
1258         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1259         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1260         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1261 }
1262
1263 static void ext4_group_desc_free(struct ext4_sb_info *sbi)
1264 {
1265         struct buffer_head **group_desc;
1266         int i;
1267
1268         rcu_read_lock();
1269         group_desc = rcu_dereference(sbi->s_group_desc);
1270         for (i = 0; i < sbi->s_gdb_count; i++)
1271                 brelse(group_desc[i]);
1272         kvfree(group_desc);
1273         rcu_read_unlock();
1274 }
1275
1276 static void ext4_flex_groups_free(struct ext4_sb_info *sbi)
1277 {
1278         struct flex_groups **flex_groups;
1279         int i;
1280
1281         rcu_read_lock();
1282         flex_groups = rcu_dereference(sbi->s_flex_groups);
1283         if (flex_groups) {
1284                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1285                         kvfree(flex_groups[i]);
1286                 kvfree(flex_groups);
1287         }
1288         rcu_read_unlock();
1289 }
1290
1291 static void ext4_put_super(struct super_block *sb)
1292 {
1293         struct ext4_sb_info *sbi = EXT4_SB(sb);
1294         struct ext4_super_block *es = sbi->s_es;
1295         int aborted = 0;
1296         int err;
1297
1298         /*
1299          * Unregister sysfs before destroying jbd2 journal.
1300          * Since we could still access attr_journal_task attribute via sysfs
1301          * path which could have sbi->s_journal->j_task as NULL
1302          * Unregister sysfs before flush sbi->s_sb_upd_work.
1303          * Since user may read /proc/fs/ext4/xx/mb_groups during umount, If
1304          * read metadata verify failed then will queue error work.
1305          * update_super_work will call start_this_handle may trigger
1306          * BUG_ON.
1307          */
1308         ext4_unregister_sysfs(sb);
1309
1310         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs unmount"))
1311                 ext4_msg(sb, KERN_INFO, "unmounting filesystem %pU.",
1312                          &sb->s_uuid);
1313
1314         ext4_unregister_li_request(sb);
1315         ext4_quotas_off(sb, EXT4_MAXQUOTAS);
1316
1317         flush_work(&sbi->s_sb_upd_work);
1318         destroy_workqueue(sbi->rsv_conversion_wq);
1319         ext4_release_orphan_info(sb);
1320
1321         if (sbi->s_journal) {
1322                 aborted = is_journal_aborted(sbi->s_journal);
1323                 err = jbd2_journal_destroy(sbi->s_journal);
1324                 sbi->s_journal = NULL;
1325                 if ((err < 0) && !aborted) {
1326                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1327                 }
1328         }
1329
1330         ext4_es_unregister_shrinker(sbi);
1331         timer_shutdown_sync(&sbi->s_err_report);
1332         ext4_release_system_zone(sb);
1333         ext4_mb_release(sb);
1334         ext4_ext_release(sb);
1335
1336         if (!sb_rdonly(sb) && !aborted) {
1337                 ext4_clear_feature_journal_needs_recovery(sb);
1338                 ext4_clear_feature_orphan_present(sb);
1339                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1340         }
1341         if (!sb_rdonly(sb))
1342                 ext4_commit_super(sb);
1343
1344         ext4_group_desc_free(sbi);
1345         ext4_flex_groups_free(sbi);
1346         ext4_percpu_param_destroy(sbi);
1347 #ifdef CONFIG_QUOTA
1348         for (int i = 0; i < EXT4_MAXQUOTAS; i++)
1349                 kfree(get_qf_name(sb, sbi, i));
1350 #endif
1351
1352         /* Debugging code just in case the in-memory inode orphan list
1353          * isn't empty.  The on-disk one can be non-empty if we've
1354          * detected an error and taken the fs readonly, but the
1355          * in-memory list had better be clean by this point. */
1356         if (!list_empty(&sbi->s_orphan))
1357                 dump_orphan_list(sb, sbi);
1358         ASSERT(list_empty(&sbi->s_orphan));
1359
1360         sync_blockdev(sb->s_bdev);
1361         invalidate_bdev(sb->s_bdev);
1362         if (sbi->s_journal_bdev_handle) {
1363                 /*
1364                  * Invalidate the journal device's buffers.  We don't want them
1365                  * floating about in memory - the physical journal device may
1366                  * hotswapped, and it breaks the `ro-after' testing code.
1367                  */
1368                 sync_blockdev(sbi->s_journal_bdev_handle->bdev);
1369                 invalidate_bdev(sbi->s_journal_bdev_handle->bdev);
1370         }
1371
1372         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1373         sbi->s_ea_inode_cache = NULL;
1374
1375         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1376         sbi->s_ea_block_cache = NULL;
1377
1378         ext4_stop_mmpd(sbi);
1379
1380         brelse(sbi->s_sbh);
1381         sb->s_fs_info = NULL;
1382         /*
1383          * Now that we are completely done shutting down the
1384          * superblock, we need to actually destroy the kobject.
1385          */
1386         kobject_put(&sbi->s_kobj);
1387         wait_for_completion(&sbi->s_kobj_unregister);
1388         if (sbi->s_chksum_driver)
1389                 crypto_free_shash(sbi->s_chksum_driver);
1390         kfree(sbi->s_blockgroup_lock);
1391         fs_put_dax(sbi->s_daxdev, NULL);
1392         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1393 #if IS_ENABLED(CONFIG_UNICODE)
1394         utf8_unload(sb->s_encoding);
1395 #endif
1396         kfree(sbi);
1397 }
1398
1399 static struct kmem_cache *ext4_inode_cachep;
1400
1401 /*
1402  * Called inside transaction, so use GFP_NOFS
1403  */
1404 static struct inode *ext4_alloc_inode(struct super_block *sb)
1405 {
1406         struct ext4_inode_info *ei;
1407
1408         ei = alloc_inode_sb(sb, ext4_inode_cachep, GFP_NOFS);
1409         if (!ei)
1410                 return NULL;
1411
1412         inode_set_iversion(&ei->vfs_inode, 1);
1413         ei->i_flags = 0;
1414         spin_lock_init(&ei->i_raw_lock);
1415         ei->i_prealloc_node = RB_ROOT;
1416         atomic_set(&ei->i_prealloc_active, 0);
1417         rwlock_init(&ei->i_prealloc_lock);
1418         ext4_es_init_tree(&ei->i_es_tree);
1419         rwlock_init(&ei->i_es_lock);
1420         INIT_LIST_HEAD(&ei->i_es_list);
1421         ei->i_es_all_nr = 0;
1422         ei->i_es_shk_nr = 0;
1423         ei->i_es_shrink_lblk = 0;
1424         ei->i_reserved_data_blocks = 0;
1425         spin_lock_init(&(ei->i_block_reservation_lock));
1426         ext4_init_pending_tree(&ei->i_pending_tree);
1427 #ifdef CONFIG_QUOTA
1428         ei->i_reserved_quota = 0;
1429         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1430 #endif
1431         ei->jinode = NULL;
1432         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1433         spin_lock_init(&ei->i_completed_io_lock);
1434         ei->i_sync_tid = 0;
1435         ei->i_datasync_tid = 0;
1436         atomic_set(&ei->i_unwritten, 0);
1437         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1438         ext4_fc_init_inode(&ei->vfs_inode);
1439         mutex_init(&ei->i_fc_lock);
1440         return &ei->vfs_inode;
1441 }
1442
1443 static int ext4_drop_inode(struct inode *inode)
1444 {
1445         int drop = generic_drop_inode(inode);
1446
1447         if (!drop)
1448                 drop = fscrypt_drop_inode(inode);
1449
1450         trace_ext4_drop_inode(inode, drop);
1451         return drop;
1452 }
1453
1454 static void ext4_free_in_core_inode(struct inode *inode)
1455 {
1456         fscrypt_free_inode(inode);
1457         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1458                 pr_warn("%s: inode %ld still in fc list",
1459                         __func__, inode->i_ino);
1460         }
1461         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1462 }
1463
1464 static void ext4_destroy_inode(struct inode *inode)
1465 {
1466         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1467                 ext4_msg(inode->i_sb, KERN_ERR,
1468                          "Inode %lu (%p): orphan list check failed!",
1469                          inode->i_ino, EXT4_I(inode));
1470                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1471                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1472                                 true);
1473                 dump_stack();
1474         }
1475
1476         if (EXT4_I(inode)->i_reserved_data_blocks)
1477                 ext4_msg(inode->i_sb, KERN_ERR,
1478                          "Inode %lu (%p): i_reserved_data_blocks (%u) not cleared!",
1479                          inode->i_ino, EXT4_I(inode),
1480                          EXT4_I(inode)->i_reserved_data_blocks);
1481 }
1482
1483 static void ext4_shutdown(struct super_block *sb)
1484 {
1485        ext4_force_shutdown(sb, EXT4_GOING_FLAGS_NOLOGFLUSH);
1486 }
1487
1488 static void init_once(void *foo)
1489 {
1490         struct ext4_inode_info *ei = foo;
1491
1492         INIT_LIST_HEAD(&ei->i_orphan);
1493         init_rwsem(&ei->xattr_sem);
1494         init_rwsem(&ei->i_data_sem);
1495         inode_init_once(&ei->vfs_inode);
1496         ext4_fc_init_inode(&ei->vfs_inode);
1497 }
1498
1499 static int __init init_inodecache(void)
1500 {
1501         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1502                                 sizeof(struct ext4_inode_info), 0,
1503                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1504                                         SLAB_ACCOUNT),
1505                                 offsetof(struct ext4_inode_info, i_data),
1506                                 sizeof_field(struct ext4_inode_info, i_data),
1507                                 init_once);
1508         if (ext4_inode_cachep == NULL)
1509                 return -ENOMEM;
1510         return 0;
1511 }
1512
1513 static void destroy_inodecache(void)
1514 {
1515         /*
1516          * Make sure all delayed rcu free inodes are flushed before we
1517          * destroy cache.
1518          */
1519         rcu_barrier();
1520         kmem_cache_destroy(ext4_inode_cachep);
1521 }
1522
1523 void ext4_clear_inode(struct inode *inode)
1524 {
1525         ext4_fc_del(inode);
1526         invalidate_inode_buffers(inode);
1527         clear_inode(inode);
1528         ext4_discard_preallocations(inode, 0);
1529         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1530         dquot_drop(inode);
1531         if (EXT4_I(inode)->jinode) {
1532                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1533                                                EXT4_I(inode)->jinode);
1534                 jbd2_free_inode(EXT4_I(inode)->jinode);
1535                 EXT4_I(inode)->jinode = NULL;
1536         }
1537         fscrypt_put_encryption_info(inode);
1538         fsverity_cleanup_inode(inode);
1539 }
1540
1541 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1542                                         u64 ino, u32 generation)
1543 {
1544         struct inode *inode;
1545
1546         /*
1547          * Currently we don't know the generation for parent directory, so
1548          * a generation of 0 means "accept any"
1549          */
1550         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1551         if (IS_ERR(inode))
1552                 return ERR_CAST(inode);
1553         if (generation && inode->i_generation != generation) {
1554                 iput(inode);
1555                 return ERR_PTR(-ESTALE);
1556         }
1557
1558         return inode;
1559 }
1560
1561 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1562                                         int fh_len, int fh_type)
1563 {
1564         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1565                                     ext4_nfs_get_inode);
1566 }
1567
1568 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1569                                         int fh_len, int fh_type)
1570 {
1571         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1572                                     ext4_nfs_get_inode);
1573 }
1574
1575 static int ext4_nfs_commit_metadata(struct inode *inode)
1576 {
1577         struct writeback_control wbc = {
1578                 .sync_mode = WB_SYNC_ALL
1579         };
1580
1581         trace_ext4_nfs_commit_metadata(inode);
1582         return ext4_write_inode(inode, &wbc);
1583 }
1584
1585 #ifdef CONFIG_QUOTA
1586 static const char * const quotatypes[] = INITQFNAMES;
1587 #define QTYPE2NAME(t) (quotatypes[t])
1588
1589 static int ext4_write_dquot(struct dquot *dquot);
1590 static int ext4_acquire_dquot(struct dquot *dquot);
1591 static int ext4_release_dquot(struct dquot *dquot);
1592 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1593 static int ext4_write_info(struct super_block *sb, int type);
1594 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1595                          const struct path *path);
1596 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1597                                size_t len, loff_t off);
1598 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1599                                 const char *data, size_t len, loff_t off);
1600 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1601                              unsigned int flags);
1602
1603 static struct dquot **ext4_get_dquots(struct inode *inode)
1604 {
1605         return EXT4_I(inode)->i_dquot;
1606 }
1607
1608 static const struct dquot_operations ext4_quota_operations = {
1609         .get_reserved_space     = ext4_get_reserved_space,
1610         .write_dquot            = ext4_write_dquot,
1611         .acquire_dquot          = ext4_acquire_dquot,
1612         .release_dquot          = ext4_release_dquot,
1613         .mark_dirty             = ext4_mark_dquot_dirty,
1614         .write_info             = ext4_write_info,
1615         .alloc_dquot            = dquot_alloc,
1616         .destroy_dquot          = dquot_destroy,
1617         .get_projid             = ext4_get_projid,
1618         .get_inode_usage        = ext4_get_inode_usage,
1619         .get_next_id            = dquot_get_next_id,
1620 };
1621
1622 static const struct quotactl_ops ext4_qctl_operations = {
1623         .quota_on       = ext4_quota_on,
1624         .quota_off      = ext4_quota_off,
1625         .quota_sync     = dquot_quota_sync,
1626         .get_state      = dquot_get_state,
1627         .set_info       = dquot_set_dqinfo,
1628         .get_dqblk      = dquot_get_dqblk,
1629         .set_dqblk      = dquot_set_dqblk,
1630         .get_nextdqblk  = dquot_get_next_dqblk,
1631 };
1632 #endif
1633
1634 static const struct super_operations ext4_sops = {
1635         .alloc_inode    = ext4_alloc_inode,
1636         .free_inode     = ext4_free_in_core_inode,
1637         .destroy_inode  = ext4_destroy_inode,
1638         .write_inode    = ext4_write_inode,
1639         .dirty_inode    = ext4_dirty_inode,
1640         .drop_inode     = ext4_drop_inode,
1641         .evict_inode    = ext4_evict_inode,
1642         .put_super      = ext4_put_super,
1643         .sync_fs        = ext4_sync_fs,
1644         .freeze_fs      = ext4_freeze,
1645         .unfreeze_fs    = ext4_unfreeze,
1646         .statfs         = ext4_statfs,
1647         .show_options   = ext4_show_options,
1648         .shutdown       = ext4_shutdown,
1649 #ifdef CONFIG_QUOTA
1650         .quota_read     = ext4_quota_read,
1651         .quota_write    = ext4_quota_write,
1652         .get_dquots     = ext4_get_dquots,
1653 #endif
1654 };
1655
1656 static const struct export_operations ext4_export_ops = {
1657         .encode_fh = generic_encode_ino32_fh,
1658         .fh_to_dentry = ext4_fh_to_dentry,
1659         .fh_to_parent = ext4_fh_to_parent,
1660         .get_parent = ext4_get_parent,
1661         .commit_metadata = ext4_nfs_commit_metadata,
1662 };
1663
1664 enum {
1665         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1666         Opt_resgid, Opt_resuid, Opt_sb,
1667         Opt_nouid32, Opt_debug, Opt_removed,
1668         Opt_user_xattr, Opt_acl,
1669         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1670         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1671         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1672         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1673         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1674         Opt_inlinecrypt,
1675         Opt_usrjquota, Opt_grpjquota, Opt_quota,
1676         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1677         Opt_usrquota, Opt_grpquota, Opt_prjquota,
1678         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1679         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1680         Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
1681         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1682         Opt_inode_readahead_blks, Opt_journal_ioprio,
1683         Opt_dioread_nolock, Opt_dioread_lock,
1684         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1685         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1686         Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1687         Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
1688 #ifdef CONFIG_EXT4_DEBUG
1689         Opt_fc_debug_max_replay, Opt_fc_debug_force
1690 #endif
1691 };
1692
1693 static const struct constant_table ext4_param_errors[] = {
1694         {"continue",    EXT4_MOUNT_ERRORS_CONT},
1695         {"panic",       EXT4_MOUNT_ERRORS_PANIC},
1696         {"remount-ro",  EXT4_MOUNT_ERRORS_RO},
1697         {}
1698 };
1699
1700 static const struct constant_table ext4_param_data[] = {
1701         {"journal",     EXT4_MOUNT_JOURNAL_DATA},
1702         {"ordered",     EXT4_MOUNT_ORDERED_DATA},
1703         {"writeback",   EXT4_MOUNT_WRITEBACK_DATA},
1704         {}
1705 };
1706
1707 static const struct constant_table ext4_param_data_err[] = {
1708         {"abort",       Opt_data_err_abort},
1709         {"ignore",      Opt_data_err_ignore},
1710         {}
1711 };
1712
1713 static const struct constant_table ext4_param_jqfmt[] = {
1714         {"vfsold",      QFMT_VFS_OLD},
1715         {"vfsv0",       QFMT_VFS_V0},
1716         {"vfsv1",       QFMT_VFS_V1},
1717         {}
1718 };
1719
1720 static const struct constant_table ext4_param_dax[] = {
1721         {"always",      Opt_dax_always},
1722         {"inode",       Opt_dax_inode},
1723         {"never",       Opt_dax_never},
1724         {}
1725 };
1726
1727 /* String parameter that allows empty argument */
1728 #define fsparam_string_empty(NAME, OPT) \
1729         __fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
1730
1731 /*
1732  * Mount option specification
1733  * We don't use fsparam_flag_no because of the way we set the
1734  * options and the way we show them in _ext4_show_options(). To
1735  * keep the changes to a minimum, let's keep the negative options
1736  * separate for now.
1737  */
1738 static const struct fs_parameter_spec ext4_param_specs[] = {
1739         fsparam_flag    ("bsddf",               Opt_bsd_df),
1740         fsparam_flag    ("minixdf",             Opt_minix_df),
1741         fsparam_flag    ("grpid",               Opt_grpid),
1742         fsparam_flag    ("bsdgroups",           Opt_grpid),
1743         fsparam_flag    ("nogrpid",             Opt_nogrpid),
1744         fsparam_flag    ("sysvgroups",          Opt_nogrpid),
1745         fsparam_u32     ("resgid",              Opt_resgid),
1746         fsparam_u32     ("resuid",              Opt_resuid),
1747         fsparam_u32     ("sb",                  Opt_sb),
1748         fsparam_enum    ("errors",              Opt_errors, ext4_param_errors),
1749         fsparam_flag    ("nouid32",             Opt_nouid32),
1750         fsparam_flag    ("debug",               Opt_debug),
1751         fsparam_flag    ("oldalloc",            Opt_removed),
1752         fsparam_flag    ("orlov",               Opt_removed),
1753         fsparam_flag    ("user_xattr",          Opt_user_xattr),
1754         fsparam_flag    ("acl",                 Opt_acl),
1755         fsparam_flag    ("norecovery",          Opt_noload),
1756         fsparam_flag    ("noload",              Opt_noload),
1757         fsparam_flag    ("bh",                  Opt_removed),
1758         fsparam_flag    ("nobh",                Opt_removed),
1759         fsparam_u32     ("commit",              Opt_commit),
1760         fsparam_u32     ("min_batch_time",      Opt_min_batch_time),
1761         fsparam_u32     ("max_batch_time",      Opt_max_batch_time),
1762         fsparam_u32     ("journal_dev",         Opt_journal_dev),
1763         fsparam_bdev    ("journal_path",        Opt_journal_path),
1764         fsparam_flag    ("journal_checksum",    Opt_journal_checksum),
1765         fsparam_flag    ("nojournal_checksum",  Opt_nojournal_checksum),
1766         fsparam_flag    ("journal_async_commit",Opt_journal_async_commit),
1767         fsparam_flag    ("abort",               Opt_abort),
1768         fsparam_enum    ("data",                Opt_data, ext4_param_data),
1769         fsparam_enum    ("data_err",            Opt_data_err,
1770                                                 ext4_param_data_err),
1771         fsparam_string_empty
1772                         ("usrjquota",           Opt_usrjquota),
1773         fsparam_string_empty
1774                         ("grpjquota",           Opt_grpjquota),
1775         fsparam_enum    ("jqfmt",               Opt_jqfmt, ext4_param_jqfmt),
1776         fsparam_flag    ("grpquota",            Opt_grpquota),
1777         fsparam_flag    ("quota",               Opt_quota),
1778         fsparam_flag    ("noquota",             Opt_noquota),
1779         fsparam_flag    ("usrquota",            Opt_usrquota),
1780         fsparam_flag    ("prjquota",            Opt_prjquota),
1781         fsparam_flag    ("barrier",             Opt_barrier),
1782         fsparam_u32     ("barrier",             Opt_barrier),
1783         fsparam_flag    ("nobarrier",           Opt_nobarrier),
1784         fsparam_flag    ("i_version",           Opt_removed),
1785         fsparam_flag    ("dax",                 Opt_dax),
1786         fsparam_enum    ("dax",                 Opt_dax_type, ext4_param_dax),
1787         fsparam_u32     ("stripe",              Opt_stripe),
1788         fsparam_flag    ("delalloc",            Opt_delalloc),
1789         fsparam_flag    ("nodelalloc",          Opt_nodelalloc),
1790         fsparam_flag    ("warn_on_error",       Opt_warn_on_error),
1791         fsparam_flag    ("nowarn_on_error",     Opt_nowarn_on_error),
1792         fsparam_u32     ("debug_want_extra_isize",
1793                                                 Opt_debug_want_extra_isize),
1794         fsparam_flag    ("mblk_io_submit",      Opt_removed),
1795         fsparam_flag    ("nomblk_io_submit",    Opt_removed),
1796         fsparam_flag    ("block_validity",      Opt_block_validity),
1797         fsparam_flag    ("noblock_validity",    Opt_noblock_validity),
1798         fsparam_u32     ("inode_readahead_blks",
1799                                                 Opt_inode_readahead_blks),
1800         fsparam_u32     ("journal_ioprio",      Opt_journal_ioprio),
1801         fsparam_u32     ("auto_da_alloc",       Opt_auto_da_alloc),
1802         fsparam_flag    ("auto_da_alloc",       Opt_auto_da_alloc),
1803         fsparam_flag    ("noauto_da_alloc",     Opt_noauto_da_alloc),
1804         fsparam_flag    ("dioread_nolock",      Opt_dioread_nolock),
1805         fsparam_flag    ("nodioread_nolock",    Opt_dioread_lock),
1806         fsparam_flag    ("dioread_lock",        Opt_dioread_lock),
1807         fsparam_flag    ("discard",             Opt_discard),
1808         fsparam_flag    ("nodiscard",           Opt_nodiscard),
1809         fsparam_u32     ("init_itable",         Opt_init_itable),
1810         fsparam_flag    ("init_itable",         Opt_init_itable),
1811         fsparam_flag    ("noinit_itable",       Opt_noinit_itable),
1812 #ifdef CONFIG_EXT4_DEBUG
1813         fsparam_flag    ("fc_debug_force",      Opt_fc_debug_force),
1814         fsparam_u32     ("fc_debug_max_replay", Opt_fc_debug_max_replay),
1815 #endif
1816         fsparam_u32     ("max_dir_size_kb",     Opt_max_dir_size_kb),
1817         fsparam_flag    ("test_dummy_encryption",
1818                                                 Opt_test_dummy_encryption),
1819         fsparam_string  ("test_dummy_encryption",
1820                                                 Opt_test_dummy_encryption),
1821         fsparam_flag    ("inlinecrypt",         Opt_inlinecrypt),
1822         fsparam_flag    ("nombcache",           Opt_nombcache),
1823         fsparam_flag    ("no_mbcache",          Opt_nombcache), /* for backward compatibility */
1824         fsparam_flag    ("prefetch_block_bitmaps",
1825                                                 Opt_removed),
1826         fsparam_flag    ("no_prefetch_block_bitmaps",
1827                                                 Opt_no_prefetch_block_bitmaps),
1828         fsparam_s32     ("mb_optimize_scan",    Opt_mb_optimize_scan),
1829         fsparam_string  ("check",               Opt_removed),   /* mount option from ext2/3 */
1830         fsparam_flag    ("nocheck",             Opt_removed),   /* mount option from ext2/3 */
1831         fsparam_flag    ("reservation",         Opt_removed),   /* mount option from ext2/3 */
1832         fsparam_flag    ("noreservation",       Opt_removed),   /* mount option from ext2/3 */
1833         fsparam_u32     ("journal",             Opt_removed),   /* mount option from ext2/3 */
1834         {}
1835 };
1836
1837 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1838
1839 #define MOPT_SET        0x0001
1840 #define MOPT_CLEAR      0x0002
1841 #define MOPT_NOSUPPORT  0x0004
1842 #define MOPT_EXPLICIT   0x0008
1843 #ifdef CONFIG_QUOTA
1844 #define MOPT_Q          0
1845 #define MOPT_QFMT       0x0010
1846 #else
1847 #define MOPT_Q          MOPT_NOSUPPORT
1848 #define MOPT_QFMT       MOPT_NOSUPPORT
1849 #endif
1850 #define MOPT_NO_EXT2    0x0020
1851 #define MOPT_NO_EXT3    0x0040
1852 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1853 #define MOPT_SKIP       0x0080
1854 #define MOPT_2          0x0100
1855
1856 static const struct mount_opts {
1857         int     token;
1858         int     mount_opt;
1859         int     flags;
1860 } ext4_mount_opts[] = {
1861         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1862         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1863         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1864         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1865         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1866         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1867         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1868          MOPT_EXT4_ONLY | MOPT_SET},
1869         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1870          MOPT_EXT4_ONLY | MOPT_CLEAR},
1871         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1872         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1873         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1874          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1875         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1876          MOPT_EXT4_ONLY | MOPT_CLEAR},
1877         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1878         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1879         {Opt_commit, 0, MOPT_NO_EXT2},
1880         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1881          MOPT_EXT4_ONLY | MOPT_CLEAR},
1882         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1883          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1884         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1885                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1886          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1887         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1888         {Opt_data_err, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_NO_EXT2},
1889         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1890         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1891         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1892         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1893         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1894         {Opt_dax_type, 0, MOPT_EXT4_ONLY},
1895         {Opt_journal_dev, 0, MOPT_NO_EXT2},
1896         {Opt_journal_path, 0, MOPT_NO_EXT2},
1897         {Opt_journal_ioprio, 0, MOPT_NO_EXT2},
1898         {Opt_data, 0, MOPT_NO_EXT2},
1899         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1900 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1901         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1902 #else
1903         {Opt_acl, 0, MOPT_NOSUPPORT},
1904 #endif
1905         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1906         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1907         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1908         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1909                                                         MOPT_SET | MOPT_Q},
1910         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1911                                                         MOPT_SET | MOPT_Q},
1912         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1913                                                         MOPT_SET | MOPT_Q},
1914         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1915                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1916                                                         MOPT_CLEAR | MOPT_Q},
1917         {Opt_usrjquota, 0, MOPT_Q},
1918         {Opt_grpjquota, 0, MOPT_Q},
1919         {Opt_jqfmt, 0, MOPT_QFMT},
1920         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1921         {Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
1922          MOPT_SET},
1923 #ifdef CONFIG_EXT4_DEBUG
1924         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1925          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1926 #endif
1927         {Opt_abort, EXT4_MOUNT2_ABORT, MOPT_SET | MOPT_2},
1928         {Opt_err, 0, 0}
1929 };
1930
1931 #if IS_ENABLED(CONFIG_UNICODE)
1932 static const struct ext4_sb_encodings {
1933         __u16 magic;
1934         char *name;
1935         unsigned int version;
1936 } ext4_sb_encoding_map[] = {
1937         {EXT4_ENC_UTF8_12_1, "utf8", UNICODE_AGE(12, 1, 0)},
1938 };
1939
1940 static const struct ext4_sb_encodings *
1941 ext4_sb_read_encoding(const struct ext4_super_block *es)
1942 {
1943         __u16 magic = le16_to_cpu(es->s_encoding);
1944         int i;
1945
1946         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1947                 if (magic == ext4_sb_encoding_map[i].magic)
1948                         return &ext4_sb_encoding_map[i];
1949
1950         return NULL;
1951 }
1952 #endif
1953
1954 #define EXT4_SPEC_JQUOTA                        (1 <<  0)
1955 #define EXT4_SPEC_JQFMT                         (1 <<  1)
1956 #define EXT4_SPEC_DATAJ                         (1 <<  2)
1957 #define EXT4_SPEC_SB_BLOCK                      (1 <<  3)
1958 #define EXT4_SPEC_JOURNAL_DEV                   (1 <<  4)
1959 #define EXT4_SPEC_JOURNAL_IOPRIO                (1 <<  5)
1960 #define EXT4_SPEC_s_want_extra_isize            (1 <<  7)
1961 #define EXT4_SPEC_s_max_batch_time              (1 <<  8)
1962 #define EXT4_SPEC_s_min_batch_time              (1 <<  9)
1963 #define EXT4_SPEC_s_inode_readahead_blks        (1 << 10)
1964 #define EXT4_SPEC_s_li_wait_mult                (1 << 11)
1965 #define EXT4_SPEC_s_max_dir_size_kb             (1 << 12)
1966 #define EXT4_SPEC_s_stripe                      (1 << 13)
1967 #define EXT4_SPEC_s_resuid                      (1 << 14)
1968 #define EXT4_SPEC_s_resgid                      (1 << 15)
1969 #define EXT4_SPEC_s_commit_interval             (1 << 16)
1970 #define EXT4_SPEC_s_fc_debug_max_replay         (1 << 17)
1971 #define EXT4_SPEC_s_sb_block                    (1 << 18)
1972 #define EXT4_SPEC_mb_optimize_scan              (1 << 19)
1973
1974 struct ext4_fs_context {
1975         char            *s_qf_names[EXT4_MAXQUOTAS];
1976         struct fscrypt_dummy_policy dummy_enc_policy;
1977         int             s_jquota_fmt;   /* Format of quota to use */
1978 #ifdef CONFIG_EXT4_DEBUG
1979         int s_fc_debug_max_replay;
1980 #endif
1981         unsigned short  qname_spec;
1982         unsigned long   vals_s_flags;   /* Bits to set in s_flags */
1983         unsigned long   mask_s_flags;   /* Bits changed in s_flags */
1984         unsigned long   journal_devnum;
1985         unsigned long   s_commit_interval;
1986         unsigned long   s_stripe;
1987         unsigned int    s_inode_readahead_blks;
1988         unsigned int    s_want_extra_isize;
1989         unsigned int    s_li_wait_mult;
1990         unsigned int    s_max_dir_size_kb;
1991         unsigned int    journal_ioprio;
1992         unsigned int    vals_s_mount_opt;
1993         unsigned int    mask_s_mount_opt;
1994         unsigned int    vals_s_mount_opt2;
1995         unsigned int    mask_s_mount_opt2;
1996         unsigned int    opt_flags;      /* MOPT flags */
1997         unsigned int    spec;
1998         u32             s_max_batch_time;
1999         u32             s_min_batch_time;
2000         kuid_t          s_resuid;
2001         kgid_t          s_resgid;
2002         ext4_fsblk_t    s_sb_block;
2003 };
2004
2005 static void ext4_fc_free(struct fs_context *fc)
2006 {
2007         struct ext4_fs_context *ctx = fc->fs_private;
2008         int i;
2009
2010         if (!ctx)
2011                 return;
2012
2013         for (i = 0; i < EXT4_MAXQUOTAS; i++)
2014                 kfree(ctx->s_qf_names[i]);
2015
2016         fscrypt_free_dummy_policy(&ctx->dummy_enc_policy);
2017         kfree(ctx);
2018 }
2019
2020 int ext4_init_fs_context(struct fs_context *fc)
2021 {
2022         struct ext4_fs_context *ctx;
2023
2024         ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2025         if (!ctx)
2026                 return -ENOMEM;
2027
2028         fc->fs_private = ctx;
2029         fc->ops = &ext4_context_ops;
2030
2031         return 0;
2032 }
2033
2034 #ifdef CONFIG_QUOTA
2035 /*
2036  * Note the name of the specified quota file.
2037  */
2038 static int note_qf_name(struct fs_context *fc, int qtype,
2039                        struct fs_parameter *param)
2040 {
2041         struct ext4_fs_context *ctx = fc->fs_private;
2042         char *qname;
2043
2044         if (param->size < 1) {
2045                 ext4_msg(NULL, KERN_ERR, "Missing quota name");
2046                 return -EINVAL;
2047         }
2048         if (strchr(param->string, '/')) {
2049                 ext4_msg(NULL, KERN_ERR,
2050                          "quotafile must be on filesystem root");
2051                 return -EINVAL;
2052         }
2053         if (ctx->s_qf_names[qtype]) {
2054                 if (strcmp(ctx->s_qf_names[qtype], param->string) != 0) {
2055                         ext4_msg(NULL, KERN_ERR,
2056                                  "%s quota file already specified",
2057                                  QTYPE2NAME(qtype));
2058                         return -EINVAL;
2059                 }
2060                 return 0;
2061         }
2062
2063         qname = kmemdup_nul(param->string, param->size, GFP_KERNEL);
2064         if (!qname) {
2065                 ext4_msg(NULL, KERN_ERR,
2066                          "Not enough memory for storing quotafile name");
2067                 return -ENOMEM;
2068         }
2069         ctx->s_qf_names[qtype] = qname;
2070         ctx->qname_spec |= 1 << qtype;
2071         ctx->spec |= EXT4_SPEC_JQUOTA;
2072         return 0;
2073 }
2074
2075 /*
2076  * Clear the name of the specified quota file.
2077  */
2078 static int unnote_qf_name(struct fs_context *fc, int qtype)
2079 {
2080         struct ext4_fs_context *ctx = fc->fs_private;
2081
2082         if (ctx->s_qf_names[qtype])
2083                 kfree(ctx->s_qf_names[qtype]);
2084
2085         ctx->s_qf_names[qtype] = NULL;
2086         ctx->qname_spec |= 1 << qtype;
2087         ctx->spec |= EXT4_SPEC_JQUOTA;
2088         return 0;
2089 }
2090 #endif
2091
2092 static int ext4_parse_test_dummy_encryption(const struct fs_parameter *param,
2093                                             struct ext4_fs_context *ctx)
2094 {
2095         int err;
2096
2097         if (!IS_ENABLED(CONFIG_FS_ENCRYPTION)) {
2098                 ext4_msg(NULL, KERN_WARNING,
2099                          "test_dummy_encryption option not supported");
2100                 return -EINVAL;
2101         }
2102         err = fscrypt_parse_test_dummy_encryption(param,
2103                                                   &ctx->dummy_enc_policy);
2104         if (err == -EINVAL) {
2105                 ext4_msg(NULL, KERN_WARNING,
2106                          "Value of option \"%s\" is unrecognized", param->key);
2107         } else if (err == -EEXIST) {
2108                 ext4_msg(NULL, KERN_WARNING,
2109                          "Conflicting test_dummy_encryption options");
2110                 return -EINVAL;
2111         }
2112         return err;
2113 }
2114
2115 #define EXT4_SET_CTX(name)                                              \
2116 static inline void ctx_set_##name(struct ext4_fs_context *ctx,          \
2117                                   unsigned long flag)                   \
2118 {                                                                       \
2119         ctx->mask_s_##name |= flag;                                     \
2120         ctx->vals_s_##name |= flag;                                     \
2121 }
2122
2123 #define EXT4_CLEAR_CTX(name)                                            \
2124 static inline void ctx_clear_##name(struct ext4_fs_context *ctx,        \
2125                                     unsigned long flag)                 \
2126 {                                                                       \
2127         ctx->mask_s_##name |= flag;                                     \
2128         ctx->vals_s_##name &= ~flag;                                    \
2129 }
2130
2131 #define EXT4_TEST_CTX(name)                                             \
2132 static inline unsigned long                                             \
2133 ctx_test_##name(struct ext4_fs_context *ctx, unsigned long flag)        \
2134 {                                                                       \
2135         return (ctx->vals_s_##name & flag);                             \
2136 }
2137
2138 EXT4_SET_CTX(flags); /* set only */
2139 EXT4_SET_CTX(mount_opt);
2140 EXT4_CLEAR_CTX(mount_opt);
2141 EXT4_TEST_CTX(mount_opt);
2142 EXT4_SET_CTX(mount_opt2);
2143 EXT4_CLEAR_CTX(mount_opt2);
2144 EXT4_TEST_CTX(mount_opt2);
2145
2146 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
2147 {
2148         struct ext4_fs_context *ctx = fc->fs_private;
2149         struct fs_parse_result result;
2150         const struct mount_opts *m;
2151         int is_remount;
2152         kuid_t uid;
2153         kgid_t gid;
2154         int token;
2155
2156         token = fs_parse(fc, ext4_param_specs, param, &result);
2157         if (token < 0)
2158                 return token;
2159         is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2160
2161         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2162                 if (token == m->token)
2163                         break;
2164
2165         ctx->opt_flags |= m->flags;
2166
2167         if (m->flags & MOPT_EXPLICIT) {
2168                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2169                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_EXPLICIT_DELALLOC);
2170                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2171                         ctx_set_mount_opt2(ctx,
2172                                        EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM);
2173                 } else
2174                         return -EINVAL;
2175         }
2176
2177         if (m->flags & MOPT_NOSUPPORT) {
2178                 ext4_msg(NULL, KERN_ERR, "%s option not supported",
2179                          param->key);
2180                 return 0;
2181         }
2182
2183         switch (token) {
2184 #ifdef CONFIG_QUOTA
2185         case Opt_usrjquota:
2186                 if (!*param->string)
2187                         return unnote_qf_name(fc, USRQUOTA);
2188                 else
2189                         return note_qf_name(fc, USRQUOTA, param);
2190         case Opt_grpjquota:
2191                 if (!*param->string)
2192                         return unnote_qf_name(fc, GRPQUOTA);
2193                 else
2194                         return note_qf_name(fc, GRPQUOTA, param);
2195 #endif
2196         case Opt_sb:
2197                 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2198                         ext4_msg(NULL, KERN_WARNING,
2199                                  "Ignoring %s option on remount", param->key);
2200                 } else {
2201                         ctx->s_sb_block = result.uint_32;
2202                         ctx->spec |= EXT4_SPEC_s_sb_block;
2203                 }
2204                 return 0;
2205         case Opt_removed:
2206                 ext4_msg(NULL, KERN_WARNING, "Ignoring removed %s option",
2207                          param->key);
2208                 return 0;
2209         case Opt_inlinecrypt:
2210 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2211                 ctx_set_flags(ctx, SB_INLINECRYPT);
2212 #else
2213                 ext4_msg(NULL, KERN_ERR, "inline encryption not supported");
2214 #endif
2215                 return 0;
2216         case Opt_errors:
2217                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_ERRORS_MASK);
2218                 ctx_set_mount_opt(ctx, result.uint_32);
2219                 return 0;
2220 #ifdef CONFIG_QUOTA
2221         case Opt_jqfmt:
2222                 ctx->s_jquota_fmt = result.uint_32;
2223                 ctx->spec |= EXT4_SPEC_JQFMT;
2224                 return 0;
2225 #endif
2226         case Opt_data:
2227                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2228                 ctx_set_mount_opt(ctx, result.uint_32);
2229                 ctx->spec |= EXT4_SPEC_DATAJ;
2230                 return 0;
2231         case Opt_commit:
2232                 if (result.uint_32 == 0)
2233                         result.uint_32 = JBD2_DEFAULT_MAX_COMMIT_AGE;
2234                 else if (result.uint_32 > INT_MAX / HZ) {
2235                         ext4_msg(NULL, KERN_ERR,
2236                                  "Invalid commit interval %d, "
2237                                  "must be smaller than %d",
2238                                  result.uint_32, INT_MAX / HZ);
2239                         return -EINVAL;
2240                 }
2241                 ctx->s_commit_interval = HZ * result.uint_32;
2242                 ctx->spec |= EXT4_SPEC_s_commit_interval;
2243                 return 0;
2244         case Opt_debug_want_extra_isize:
2245                 if ((result.uint_32 & 1) || (result.uint_32 < 4)) {
2246                         ext4_msg(NULL, KERN_ERR,
2247                                  "Invalid want_extra_isize %d", result.uint_32);
2248                         return -EINVAL;
2249                 }
2250                 ctx->s_want_extra_isize = result.uint_32;
2251                 ctx->spec |= EXT4_SPEC_s_want_extra_isize;
2252                 return 0;
2253         case Opt_max_batch_time:
2254                 ctx->s_max_batch_time = result.uint_32;
2255                 ctx->spec |= EXT4_SPEC_s_max_batch_time;
2256                 return 0;
2257         case Opt_min_batch_time:
2258                 ctx->s_min_batch_time = result.uint_32;
2259                 ctx->spec |= EXT4_SPEC_s_min_batch_time;
2260                 return 0;
2261         case Opt_inode_readahead_blks:
2262                 if (result.uint_32 &&
2263                     (result.uint_32 > (1 << 30) ||
2264                      !is_power_of_2(result.uint_32))) {
2265                         ext4_msg(NULL, KERN_ERR,
2266                                  "EXT4-fs: inode_readahead_blks must be "
2267                                  "0 or a power of 2 smaller than 2^31");
2268                         return -EINVAL;
2269                 }
2270                 ctx->s_inode_readahead_blks = result.uint_32;
2271                 ctx->spec |= EXT4_SPEC_s_inode_readahead_blks;
2272                 return 0;
2273         case Opt_init_itable:
2274                 ctx_set_mount_opt(ctx, EXT4_MOUNT_INIT_INODE_TABLE);
2275                 ctx->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
2276                 if (param->type == fs_value_is_string)
2277                         ctx->s_li_wait_mult = result.uint_32;
2278                 ctx->spec |= EXT4_SPEC_s_li_wait_mult;
2279                 return 0;
2280         case Opt_max_dir_size_kb:
2281                 ctx->s_max_dir_size_kb = result.uint_32;
2282                 ctx->spec |= EXT4_SPEC_s_max_dir_size_kb;
2283                 return 0;
2284 #ifdef CONFIG_EXT4_DEBUG
2285         case Opt_fc_debug_max_replay:
2286                 ctx->s_fc_debug_max_replay = result.uint_32;
2287                 ctx->spec |= EXT4_SPEC_s_fc_debug_max_replay;
2288                 return 0;
2289 #endif
2290         case Opt_stripe:
2291                 ctx->s_stripe = result.uint_32;
2292                 ctx->spec |= EXT4_SPEC_s_stripe;
2293                 return 0;
2294         case Opt_resuid:
2295                 uid = make_kuid(current_user_ns(), result.uint_32);
2296                 if (!uid_valid(uid)) {
2297                         ext4_msg(NULL, KERN_ERR, "Invalid uid value %d",
2298                                  result.uint_32);
2299                         return -EINVAL;
2300                 }
2301                 ctx->s_resuid = uid;
2302                 ctx->spec |= EXT4_SPEC_s_resuid;
2303                 return 0;
2304         case Opt_resgid:
2305                 gid = make_kgid(current_user_ns(), result.uint_32);
2306                 if (!gid_valid(gid)) {
2307                         ext4_msg(NULL, KERN_ERR, "Invalid gid value %d",
2308                                  result.uint_32);
2309                         return -EINVAL;
2310                 }
2311                 ctx->s_resgid = gid;
2312                 ctx->spec |= EXT4_SPEC_s_resgid;
2313                 return 0;
2314         case Opt_journal_dev:
2315                 if (is_remount) {
2316                         ext4_msg(NULL, KERN_ERR,
2317                                  "Cannot specify journal on remount");
2318                         return -EINVAL;
2319                 }
2320                 ctx->journal_devnum = result.uint_32;
2321                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2322                 return 0;
2323         case Opt_journal_path:
2324         {
2325                 struct inode *journal_inode;
2326                 struct path path;
2327                 int error;
2328
2329                 if (is_remount) {
2330                         ext4_msg(NULL, KERN_ERR,
2331                                  "Cannot specify journal on remount");
2332                         return -EINVAL;
2333                 }
2334
2335                 error = fs_lookup_param(fc, param, 1, LOOKUP_FOLLOW, &path);
2336                 if (error) {
2337                         ext4_msg(NULL, KERN_ERR, "error: could not find "
2338                                  "journal device path");
2339                         return -EINVAL;
2340                 }
2341
2342                 journal_inode = d_inode(path.dentry);
2343                 ctx->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2344                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2345                 path_put(&path);
2346                 return 0;
2347         }
2348         case Opt_journal_ioprio:
2349                 if (result.uint_32 > 7) {
2350                         ext4_msg(NULL, KERN_ERR, "Invalid journal IO priority"
2351                                  " (must be 0-7)");
2352                         return -EINVAL;
2353                 }
2354                 ctx->journal_ioprio =
2355                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, result.uint_32);
2356                 ctx->spec |= EXT4_SPEC_JOURNAL_IOPRIO;
2357                 return 0;
2358         case Opt_test_dummy_encryption:
2359                 return ext4_parse_test_dummy_encryption(param, ctx);
2360         case Opt_dax:
2361         case Opt_dax_type:
2362 #ifdef CONFIG_FS_DAX
2363         {
2364                 int type = (token == Opt_dax) ?
2365                            Opt_dax : result.uint_32;
2366
2367                 switch (type) {
2368                 case Opt_dax:
2369                 case Opt_dax_always:
2370                         ctx_set_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2371                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2372                         break;
2373                 case Opt_dax_never:
2374                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2375                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2376                         break;
2377                 case Opt_dax_inode:
2378                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2379                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2380                         /* Strictly for printing options */
2381                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE);
2382                         break;
2383                 }
2384                 return 0;
2385         }
2386 #else
2387                 ext4_msg(NULL, KERN_INFO, "dax option not supported");
2388                 return -EINVAL;
2389 #endif
2390         case Opt_data_err:
2391                 if (result.uint_32 == Opt_data_err_abort)
2392                         ctx_set_mount_opt(ctx, m->mount_opt);
2393                 else if (result.uint_32 == Opt_data_err_ignore)
2394                         ctx_clear_mount_opt(ctx, m->mount_opt);
2395                 return 0;
2396         case Opt_mb_optimize_scan:
2397                 if (result.int_32 == 1) {
2398                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2399                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2400                 } else if (result.int_32 == 0) {
2401                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2402                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2403                 } else {
2404                         ext4_msg(NULL, KERN_WARNING,
2405                                  "mb_optimize_scan should be set to 0 or 1.");
2406                         return -EINVAL;
2407                 }
2408                 return 0;
2409         }
2410
2411         /*
2412          * At this point we should only be getting options requiring MOPT_SET,
2413          * or MOPT_CLEAR. Anything else is a bug
2414          */
2415         if (m->token == Opt_err) {
2416                 ext4_msg(NULL, KERN_WARNING, "buggy handling of option %s",
2417                          param->key);
2418                 WARN_ON(1);
2419                 return -EINVAL;
2420         }
2421
2422         else {
2423                 unsigned int set = 0;
2424
2425                 if ((param->type == fs_value_is_flag) ||
2426                     result.uint_32 > 0)
2427                         set = 1;
2428
2429                 if (m->flags & MOPT_CLEAR)
2430                         set = !set;
2431                 else if (unlikely(!(m->flags & MOPT_SET))) {
2432                         ext4_msg(NULL, KERN_WARNING,
2433                                  "buggy handling of option %s",
2434                                  param->key);
2435                         WARN_ON(1);
2436                         return -EINVAL;
2437                 }
2438                 if (m->flags & MOPT_2) {
2439                         if (set != 0)
2440                                 ctx_set_mount_opt2(ctx, m->mount_opt);
2441                         else
2442                                 ctx_clear_mount_opt2(ctx, m->mount_opt);
2443                 } else {
2444                         if (set != 0)
2445                                 ctx_set_mount_opt(ctx, m->mount_opt);
2446                         else
2447                                 ctx_clear_mount_opt(ctx, m->mount_opt);
2448                 }
2449         }
2450
2451         return 0;
2452 }
2453
2454 static int parse_options(struct fs_context *fc, char *options)
2455 {
2456         struct fs_parameter param;
2457         int ret;
2458         char *key;
2459
2460         if (!options)
2461                 return 0;
2462
2463         while ((key = strsep(&options, ",")) != NULL) {
2464                 if (*key) {
2465                         size_t v_len = 0;
2466                         char *value = strchr(key, '=');
2467
2468                         param.type = fs_value_is_flag;
2469                         param.string = NULL;
2470
2471                         if (value) {
2472                                 if (value == key)
2473                                         continue;
2474
2475                                 *value++ = 0;
2476                                 v_len = strlen(value);
2477                                 param.string = kmemdup_nul(value, v_len,
2478                                                            GFP_KERNEL);
2479                                 if (!param.string)
2480                                         return -ENOMEM;
2481                                 param.type = fs_value_is_string;
2482                         }
2483
2484                         param.key = key;
2485                         param.size = v_len;
2486
2487                         ret = ext4_parse_param(fc, &param);
2488                         if (param.string)
2489                                 kfree(param.string);
2490                         if (ret < 0)
2491                                 return ret;
2492                 }
2493         }
2494
2495         ret = ext4_validate_options(fc);
2496         if (ret < 0)
2497                 return ret;
2498
2499         return 0;
2500 }
2501
2502 static int parse_apply_sb_mount_options(struct super_block *sb,
2503                                         struct ext4_fs_context *m_ctx)
2504 {
2505         struct ext4_sb_info *sbi = EXT4_SB(sb);
2506         char *s_mount_opts = NULL;
2507         struct ext4_fs_context *s_ctx = NULL;
2508         struct fs_context *fc = NULL;
2509         int ret = -ENOMEM;
2510
2511         if (!sbi->s_es->s_mount_opts[0])
2512                 return 0;
2513
2514         s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
2515                                 sizeof(sbi->s_es->s_mount_opts),
2516                                 GFP_KERNEL);
2517         if (!s_mount_opts)
2518                 return ret;
2519
2520         fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
2521         if (!fc)
2522                 goto out_free;
2523
2524         s_ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2525         if (!s_ctx)
2526                 goto out_free;
2527
2528         fc->fs_private = s_ctx;
2529         fc->s_fs_info = sbi;
2530
2531         ret = parse_options(fc, s_mount_opts);
2532         if (ret < 0)
2533                 goto parse_failed;
2534
2535         ret = ext4_check_opt_consistency(fc, sb);
2536         if (ret < 0) {
2537 parse_failed:
2538                 ext4_msg(sb, KERN_WARNING,
2539                          "failed to parse options in superblock: %s",
2540                          s_mount_opts);
2541                 ret = 0;
2542                 goto out_free;
2543         }
2544
2545         if (s_ctx->spec & EXT4_SPEC_JOURNAL_DEV)
2546                 m_ctx->journal_devnum = s_ctx->journal_devnum;
2547         if (s_ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)
2548                 m_ctx->journal_ioprio = s_ctx->journal_ioprio;
2549
2550         ext4_apply_options(fc, sb);
2551         ret = 0;
2552
2553 out_free:
2554         if (fc) {
2555                 ext4_fc_free(fc);
2556                 kfree(fc);
2557         }
2558         kfree(s_mount_opts);
2559         return ret;
2560 }
2561
2562 static void ext4_apply_quota_options(struct fs_context *fc,
2563                                      struct super_block *sb)
2564 {
2565 #ifdef CONFIG_QUOTA
2566         bool quota_feature = ext4_has_feature_quota(sb);
2567         struct ext4_fs_context *ctx = fc->fs_private;
2568         struct ext4_sb_info *sbi = EXT4_SB(sb);
2569         char *qname;
2570         int i;
2571
2572         if (quota_feature)
2573                 return;
2574
2575         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2576                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2577                         if (!(ctx->qname_spec & (1 << i)))
2578                                 continue;
2579
2580                         qname = ctx->s_qf_names[i]; /* May be NULL */
2581                         if (qname)
2582                                 set_opt(sb, QUOTA);
2583                         ctx->s_qf_names[i] = NULL;
2584                         qname = rcu_replace_pointer(sbi->s_qf_names[i], qname,
2585                                                 lockdep_is_held(&sb->s_umount));
2586                         if (qname)
2587                                 kfree_rcu_mightsleep(qname);
2588                 }
2589         }
2590
2591         if (ctx->spec & EXT4_SPEC_JQFMT)
2592                 sbi->s_jquota_fmt = ctx->s_jquota_fmt;
2593 #endif
2594 }
2595
2596 /*
2597  * Check quota settings consistency.
2598  */
2599 static int ext4_check_quota_consistency(struct fs_context *fc,
2600                                         struct super_block *sb)
2601 {
2602 #ifdef CONFIG_QUOTA
2603         struct ext4_fs_context *ctx = fc->fs_private;
2604         struct ext4_sb_info *sbi = EXT4_SB(sb);
2605         bool quota_feature = ext4_has_feature_quota(sb);
2606         bool quota_loaded = sb_any_quota_loaded(sb);
2607         bool usr_qf_name, grp_qf_name, usrquota, grpquota;
2608         int quota_flags, i;
2609
2610         /*
2611          * We do the test below only for project quotas. 'usrquota' and
2612          * 'grpquota' mount options are allowed even without quota feature
2613          * to support legacy quotas in quota files.
2614          */
2615         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_PRJQUOTA) &&
2616             !ext4_has_feature_project(sb)) {
2617                 ext4_msg(NULL, KERN_ERR, "Project quota feature not enabled. "
2618                          "Cannot enable project quota enforcement.");
2619                 return -EINVAL;
2620         }
2621
2622         quota_flags = EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2623                       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA;
2624         if (quota_loaded &&
2625             ctx->mask_s_mount_opt & quota_flags &&
2626             !ctx_test_mount_opt(ctx, quota_flags))
2627                 goto err_quota_change;
2628
2629         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2630
2631                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2632                         if (!(ctx->qname_spec & (1 << i)))
2633                                 continue;
2634
2635                         if (quota_loaded &&
2636                             !!sbi->s_qf_names[i] != !!ctx->s_qf_names[i])
2637                                 goto err_jquota_change;
2638
2639                         if (sbi->s_qf_names[i] && ctx->s_qf_names[i] &&
2640                             strcmp(get_qf_name(sb, sbi, i),
2641                                    ctx->s_qf_names[i]) != 0)
2642                                 goto err_jquota_specified;
2643                 }
2644
2645                 if (quota_feature) {
2646                         ext4_msg(NULL, KERN_INFO,
2647                                  "Journaled quota options ignored when "
2648                                  "QUOTA feature is enabled");
2649                         return 0;
2650                 }
2651         }
2652
2653         if (ctx->spec & EXT4_SPEC_JQFMT) {
2654                 if (sbi->s_jquota_fmt != ctx->s_jquota_fmt && quota_loaded)
2655                         goto err_jquota_change;
2656                 if (quota_feature) {
2657                         ext4_msg(NULL, KERN_INFO, "Quota format mount options "
2658                                  "ignored when QUOTA feature is enabled");
2659                         return 0;
2660                 }
2661         }
2662
2663         /* Make sure we don't mix old and new quota format */
2664         usr_qf_name = (get_qf_name(sb, sbi, USRQUOTA) ||
2665                        ctx->s_qf_names[USRQUOTA]);
2666         grp_qf_name = (get_qf_name(sb, sbi, GRPQUOTA) ||
2667                        ctx->s_qf_names[GRPQUOTA]);
2668
2669         usrquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2670                     test_opt(sb, USRQUOTA));
2671
2672         grpquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) ||
2673                     test_opt(sb, GRPQUOTA));
2674
2675         if (usr_qf_name) {
2676                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2677                 usrquota = false;
2678         }
2679         if (grp_qf_name) {
2680                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2681                 grpquota = false;
2682         }
2683
2684         if (usr_qf_name || grp_qf_name) {
2685                 if (usrquota || grpquota) {
2686                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2687                                  "format mixing");
2688                         return -EINVAL;
2689                 }
2690
2691                 if (!(ctx->spec & EXT4_SPEC_JQFMT || sbi->s_jquota_fmt)) {
2692                         ext4_msg(NULL, KERN_ERR, "journaled quota format "
2693                                  "not specified");
2694                         return -EINVAL;
2695                 }
2696         }
2697
2698         return 0;
2699
2700 err_quota_change:
2701         ext4_msg(NULL, KERN_ERR,
2702                  "Cannot change quota options when quota turned on");
2703         return -EINVAL;
2704 err_jquota_change:
2705         ext4_msg(NULL, KERN_ERR, "Cannot change journaled quota "
2706                  "options when quota turned on");
2707         return -EINVAL;
2708 err_jquota_specified:
2709         ext4_msg(NULL, KERN_ERR, "%s quota file already specified",
2710                  QTYPE2NAME(i));
2711         return -EINVAL;
2712 #else
2713         return 0;
2714 #endif
2715 }
2716
2717 static int ext4_check_test_dummy_encryption(const struct fs_context *fc,
2718                                             struct super_block *sb)
2719 {
2720         const struct ext4_fs_context *ctx = fc->fs_private;
2721         const struct ext4_sb_info *sbi = EXT4_SB(sb);
2722
2723         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy))
2724                 return 0;
2725
2726         if (!ext4_has_feature_encrypt(sb)) {
2727                 ext4_msg(NULL, KERN_WARNING,
2728                          "test_dummy_encryption requires encrypt feature");
2729                 return -EINVAL;
2730         }
2731         /*
2732          * This mount option is just for testing, and it's not worthwhile to
2733          * implement the extra complexity (e.g. RCU protection) that would be
2734          * needed to allow it to be set or changed during remount.  We do allow
2735          * it to be specified during remount, but only if there is no change.
2736          */
2737         if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2738                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2739                                                  &ctx->dummy_enc_policy))
2740                         return 0;
2741                 ext4_msg(NULL, KERN_WARNING,
2742                          "Can't set or change test_dummy_encryption on remount");
2743                 return -EINVAL;
2744         }
2745         /* Also make sure s_mount_opts didn't contain a conflicting value. */
2746         if (fscrypt_is_dummy_policy_set(&sbi->s_dummy_enc_policy)) {
2747                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2748                                                  &ctx->dummy_enc_policy))
2749                         return 0;
2750                 ext4_msg(NULL, KERN_WARNING,
2751                          "Conflicting test_dummy_encryption options");
2752                 return -EINVAL;
2753         }
2754         return 0;
2755 }
2756
2757 static void ext4_apply_test_dummy_encryption(struct ext4_fs_context *ctx,
2758                                              struct super_block *sb)
2759 {
2760         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy) ||
2761             /* if already set, it was already verified to be the same */
2762             fscrypt_is_dummy_policy_set(&EXT4_SB(sb)->s_dummy_enc_policy))
2763                 return;
2764         EXT4_SB(sb)->s_dummy_enc_policy = ctx->dummy_enc_policy;
2765         memset(&ctx->dummy_enc_policy, 0, sizeof(ctx->dummy_enc_policy));
2766         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2767 }
2768
2769 static int ext4_check_opt_consistency(struct fs_context *fc,
2770                                       struct super_block *sb)
2771 {
2772         struct ext4_fs_context *ctx = fc->fs_private;
2773         struct ext4_sb_info *sbi = fc->s_fs_info;
2774         int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2775         int err;
2776
2777         if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2778                 ext4_msg(NULL, KERN_ERR,
2779                          "Mount option(s) incompatible with ext2");
2780                 return -EINVAL;
2781         }
2782         if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2783                 ext4_msg(NULL, KERN_ERR,
2784                          "Mount option(s) incompatible with ext3");
2785                 return -EINVAL;
2786         }
2787
2788         if (ctx->s_want_extra_isize >
2789             (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2790                 ext4_msg(NULL, KERN_ERR,
2791                          "Invalid want_extra_isize %d",
2792                          ctx->s_want_extra_isize);
2793                 return -EINVAL;
2794         }
2795
2796         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DIOREAD_NOLOCK)) {
2797                 int blocksize =
2798                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2799                 if (blocksize < PAGE_SIZE)
2800                         ext4_msg(NULL, KERN_WARNING, "Warning: mounting with an "
2801                                  "experimental mount option 'dioread_nolock' "
2802                                  "for blocksize < PAGE_SIZE");
2803         }
2804
2805         err = ext4_check_test_dummy_encryption(fc, sb);
2806         if (err)
2807                 return err;
2808
2809         if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2810                 if (!sbi->s_journal) {
2811                         ext4_msg(NULL, KERN_WARNING,
2812                                  "Remounting file system with no journal "
2813                                  "so ignoring journalled data option");
2814                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2815                 } else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2816                            test_opt(sb, DATA_FLAGS)) {
2817                         ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2818                                  "on remount");
2819                         return -EINVAL;
2820                 }
2821         }
2822
2823         if (is_remount) {
2824                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2825                     (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2826                         ext4_msg(NULL, KERN_ERR, "can't mount with "
2827                                  "both data=journal and dax");
2828                         return -EINVAL;
2829                 }
2830
2831                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2832                     (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2833                      (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2834 fail_dax_change_remount:
2835                         ext4_msg(NULL, KERN_ERR, "can't change "
2836                                  "dax mount option while remounting");
2837                         return -EINVAL;
2838                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2839                          (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2840                           (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2841                         goto fail_dax_change_remount;
2842                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2843                            ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2844                             (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2845                             !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2846                         goto fail_dax_change_remount;
2847                 }
2848         }
2849
2850         return ext4_check_quota_consistency(fc, sb);
2851 }
2852
2853 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2854 {
2855         struct ext4_fs_context *ctx = fc->fs_private;
2856         struct ext4_sb_info *sbi = fc->s_fs_info;
2857
2858         sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2859         sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2860         sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2861         sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2862         sb->s_flags &= ~ctx->mask_s_flags;
2863         sb->s_flags |= ctx->vals_s_flags;
2864
2865 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2866         APPLY(s_commit_interval);
2867         APPLY(s_stripe);
2868         APPLY(s_max_batch_time);
2869         APPLY(s_min_batch_time);
2870         APPLY(s_want_extra_isize);
2871         APPLY(s_inode_readahead_blks);
2872         APPLY(s_max_dir_size_kb);
2873         APPLY(s_li_wait_mult);
2874         APPLY(s_resgid);
2875         APPLY(s_resuid);
2876
2877 #ifdef CONFIG_EXT4_DEBUG
2878         APPLY(s_fc_debug_max_replay);
2879 #endif
2880
2881         ext4_apply_quota_options(fc, sb);
2882         ext4_apply_test_dummy_encryption(ctx, sb);
2883 }
2884
2885
2886 static int ext4_validate_options(struct fs_context *fc)
2887 {
2888 #ifdef CONFIG_QUOTA
2889         struct ext4_fs_context *ctx = fc->fs_private;
2890         char *usr_qf_name, *grp_qf_name;
2891
2892         usr_qf_name = ctx->s_qf_names[USRQUOTA];
2893         grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2894
2895         if (usr_qf_name || grp_qf_name) {
2896                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2897                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2898
2899                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2900                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2901
2902                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2903                     ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2904                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2905                                  "format mixing");
2906                         return -EINVAL;
2907                 }
2908         }
2909 #endif
2910         return 1;
2911 }
2912
2913 static inline void ext4_show_quota_options(struct seq_file *seq,
2914                                            struct super_block *sb)
2915 {
2916 #if defined(CONFIG_QUOTA)
2917         struct ext4_sb_info *sbi = EXT4_SB(sb);
2918         char *usr_qf_name, *grp_qf_name;
2919
2920         if (sbi->s_jquota_fmt) {
2921                 char *fmtname = "";
2922
2923                 switch (sbi->s_jquota_fmt) {
2924                 case QFMT_VFS_OLD:
2925                         fmtname = "vfsold";
2926                         break;
2927                 case QFMT_VFS_V0:
2928                         fmtname = "vfsv0";
2929                         break;
2930                 case QFMT_VFS_V1:
2931                         fmtname = "vfsv1";
2932                         break;
2933                 }
2934                 seq_printf(seq, ",jqfmt=%s", fmtname);
2935         }
2936
2937         rcu_read_lock();
2938         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2939         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2940         if (usr_qf_name)
2941                 seq_show_option(seq, "usrjquota", usr_qf_name);
2942         if (grp_qf_name)
2943                 seq_show_option(seq, "grpjquota", grp_qf_name);
2944         rcu_read_unlock();
2945 #endif
2946 }
2947
2948 static const char *token2str(int token)
2949 {
2950         const struct fs_parameter_spec *spec;
2951
2952         for (spec = ext4_param_specs; spec->name != NULL; spec++)
2953                 if (spec->opt == token && !spec->type)
2954                         break;
2955         return spec->name;
2956 }
2957
2958 /*
2959  * Show an option if
2960  *  - it's set to a non-default value OR
2961  *  - if the per-sb default is different from the global default
2962  */
2963 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2964                               int nodefs)
2965 {
2966         struct ext4_sb_info *sbi = EXT4_SB(sb);
2967         struct ext4_super_block *es = sbi->s_es;
2968         int def_errors;
2969         const struct mount_opts *m;
2970         char sep = nodefs ? '\n' : ',';
2971
2972 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2973 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2974
2975         if (sbi->s_sb_block != 1)
2976                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2977
2978         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2979                 int want_set = m->flags & MOPT_SET;
2980                 int opt_2 = m->flags & MOPT_2;
2981                 unsigned int mount_opt, def_mount_opt;
2982
2983                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2984                     m->flags & MOPT_SKIP)
2985                         continue;
2986
2987                 if (opt_2) {
2988                         mount_opt = sbi->s_mount_opt2;
2989                         def_mount_opt = sbi->s_def_mount_opt2;
2990                 } else {
2991                         mount_opt = sbi->s_mount_opt;
2992                         def_mount_opt = sbi->s_def_mount_opt;
2993                 }
2994                 /* skip if same as the default */
2995                 if (!nodefs && !(m->mount_opt & (mount_opt ^ def_mount_opt)))
2996                         continue;
2997                 /* select Opt_noFoo vs Opt_Foo */
2998                 if ((want_set &&
2999                      (mount_opt & m->mount_opt) != m->mount_opt) ||
3000                     (!want_set && (mount_opt & m->mount_opt)))
3001                         continue;
3002                 SEQ_OPTS_PRINT("%s", token2str(m->token));
3003         }
3004
3005         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
3006             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
3007                 SEQ_OPTS_PRINT("resuid=%u",
3008                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
3009         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
3010             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
3011                 SEQ_OPTS_PRINT("resgid=%u",
3012                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
3013         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
3014         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
3015                 SEQ_OPTS_PUTS("errors=remount-ro");
3016         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
3017                 SEQ_OPTS_PUTS("errors=continue");
3018         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
3019                 SEQ_OPTS_PUTS("errors=panic");
3020         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
3021                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
3022         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
3023                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
3024         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
3025                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
3026         if (nodefs || sbi->s_stripe)
3027                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
3028         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
3029                         (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
3030                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3031                         SEQ_OPTS_PUTS("data=journal");
3032                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3033                         SEQ_OPTS_PUTS("data=ordered");
3034                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
3035                         SEQ_OPTS_PUTS("data=writeback");
3036         }
3037         if (nodefs ||
3038             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
3039                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
3040                                sbi->s_inode_readahead_blks);
3041
3042         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
3043                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
3044                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
3045         if (nodefs || sbi->s_max_dir_size_kb)
3046                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
3047         if (test_opt(sb, DATA_ERR_ABORT))
3048                 SEQ_OPTS_PUTS("data_err=abort");
3049
3050         fscrypt_show_test_dummy_encryption(seq, sep, sb);
3051
3052         if (sb->s_flags & SB_INLINECRYPT)
3053                 SEQ_OPTS_PUTS("inlinecrypt");
3054
3055         if (test_opt(sb, DAX_ALWAYS)) {
3056                 if (IS_EXT2_SB(sb))
3057                         SEQ_OPTS_PUTS("dax");
3058                 else
3059                         SEQ_OPTS_PUTS("dax=always");
3060         } else if (test_opt2(sb, DAX_NEVER)) {
3061                 SEQ_OPTS_PUTS("dax=never");
3062         } else if (test_opt2(sb, DAX_INODE)) {
3063                 SEQ_OPTS_PUTS("dax=inode");
3064         }
3065
3066         if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3067                         !test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3068                 SEQ_OPTS_PUTS("mb_optimize_scan=0");
3069         } else if (sbi->s_groups_count < MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3070                         test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3071                 SEQ_OPTS_PUTS("mb_optimize_scan=1");
3072         }
3073
3074         ext4_show_quota_options(seq, sb);
3075         return 0;
3076 }
3077
3078 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
3079 {
3080         return _ext4_show_options(seq, root->d_sb, 0);
3081 }
3082
3083 int ext4_seq_options_show(struct seq_file *seq, void *offset)
3084 {
3085         struct super_block *sb = seq->private;
3086         int rc;
3087
3088         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
3089         rc = _ext4_show_options(seq, sb, 1);
3090         seq_puts(seq, "\n");
3091         return rc;
3092 }
3093
3094 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3095                             int read_only)
3096 {
3097         struct ext4_sb_info *sbi = EXT4_SB(sb);
3098         int err = 0;
3099
3100         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3101                 ext4_msg(sb, KERN_ERR, "revision level too high, "
3102                          "forcing read-only mode");
3103                 err = -EROFS;
3104                 goto done;
3105         }
3106         if (read_only)
3107                 goto done;
3108         if (!(sbi->s_mount_state & EXT4_VALID_FS))
3109                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3110                          "running e2fsck is recommended");
3111         else if (sbi->s_mount_state & EXT4_ERROR_FS)
3112                 ext4_msg(sb, KERN_WARNING,
3113                          "warning: mounting fs with errors, "
3114                          "running e2fsck is recommended");
3115         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3116                  le16_to_cpu(es->s_mnt_count) >=
3117                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3118                 ext4_msg(sb, KERN_WARNING,
3119                          "warning: maximal mount count reached, "
3120                          "running e2fsck is recommended");
3121         else if (le32_to_cpu(es->s_checkinterval) &&
3122                  (ext4_get_tstamp(es, s_lastcheck) +
3123                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3124                 ext4_msg(sb, KERN_WARNING,
3125                          "warning: checktime reached, "
3126                          "running e2fsck is recommended");
3127         if (!sbi->s_journal)
3128                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3129         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3130                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3131         le16_add_cpu(&es->s_mnt_count, 1);
3132         ext4_update_tstamp(es, s_mtime);
3133         if (sbi->s_journal) {
3134                 ext4_set_feature_journal_needs_recovery(sb);
3135                 if (ext4_has_feature_orphan_file(sb))
3136                         ext4_set_feature_orphan_present(sb);
3137         }
3138
3139         err = ext4_commit_super(sb);
3140 done:
3141         if (test_opt(sb, DEBUG))
3142                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3143                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3144                         sb->s_blocksize,
3145                         sbi->s_groups_count,
3146                         EXT4_BLOCKS_PER_GROUP(sb),
3147                         EXT4_INODES_PER_GROUP(sb),
3148                         sbi->s_mount_opt, sbi->s_mount_opt2);
3149         return err;
3150 }
3151
3152 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3153 {
3154         struct ext4_sb_info *sbi = EXT4_SB(sb);
3155         struct flex_groups **old_groups, **new_groups;
3156         int size, i, j;
3157
3158         if (!sbi->s_log_groups_per_flex)
3159                 return 0;
3160
3161         size = ext4_flex_group(sbi, ngroup - 1) + 1;
3162         if (size <= sbi->s_flex_groups_allocated)
3163                 return 0;
3164
3165         new_groups = kvzalloc(roundup_pow_of_two(size *
3166                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3167         if (!new_groups) {
3168                 ext4_msg(sb, KERN_ERR,
3169                          "not enough memory for %d flex group pointers", size);
3170                 return -ENOMEM;
3171         }
3172         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3173                 new_groups[i] = kvzalloc(roundup_pow_of_two(
3174                                          sizeof(struct flex_groups)),
3175                                          GFP_KERNEL);
3176                 if (!new_groups[i]) {
3177                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
3178                                 kvfree(new_groups[j]);
3179                         kvfree(new_groups);
3180                         ext4_msg(sb, KERN_ERR,
3181                                  "not enough memory for %d flex groups", size);
3182                         return -ENOMEM;
3183                 }
3184         }
3185         rcu_read_lock();
3186         old_groups = rcu_dereference(sbi->s_flex_groups);
3187         if (old_groups)
3188                 memcpy(new_groups, old_groups,
3189                        (sbi->s_flex_groups_allocated *
3190                         sizeof(struct flex_groups *)));
3191         rcu_read_unlock();
3192         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3193         sbi->s_flex_groups_allocated = size;
3194         if (old_groups)
3195                 ext4_kvfree_array_rcu(old_groups);
3196         return 0;
3197 }
3198
3199 static int ext4_fill_flex_info(struct super_block *sb)
3200 {
3201         struct ext4_sb_info *sbi = EXT4_SB(sb);
3202         struct ext4_group_desc *gdp = NULL;
3203         struct flex_groups *fg;
3204         ext4_group_t flex_group;
3205         int i, err;
3206
3207         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3208         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3209                 sbi->s_log_groups_per_flex = 0;
3210                 return 1;
3211         }
3212
3213         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3214         if (err)
3215                 goto failed;
3216
3217         for (i = 0; i < sbi->s_groups_count; i++) {
3218                 gdp = ext4_get_group_desc(sb, i, NULL);
3219
3220                 flex_group = ext4_flex_group(sbi, i);
3221                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3222                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3223                 atomic64_add(ext4_free_group_clusters(sb, gdp),
3224                              &fg->free_clusters);
3225                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3226         }
3227
3228         return 1;
3229 failed:
3230         return 0;
3231 }
3232
3233 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3234                                    struct ext4_group_desc *gdp)
3235 {
3236         int offset = offsetof(struct ext4_group_desc, bg_checksum);
3237         __u16 crc = 0;
3238         __le32 le_group = cpu_to_le32(block_group);
3239         struct ext4_sb_info *sbi = EXT4_SB(sb);
3240
3241         if (ext4_has_metadata_csum(sbi->s_sb)) {
3242                 /* Use new metadata_csum algorithm */
3243                 __u32 csum32;
3244                 __u16 dummy_csum = 0;
3245
3246                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
3247                                      sizeof(le_group));
3248                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
3249                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
3250                                      sizeof(dummy_csum));
3251                 offset += sizeof(dummy_csum);
3252                 if (offset < sbi->s_desc_size)
3253                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
3254                                              sbi->s_desc_size - offset);
3255
3256                 crc = csum32 & 0xFFFF;
3257                 goto out;
3258         }
3259
3260         /* old crc16 code */
3261         if (!ext4_has_feature_gdt_csum(sb))
3262                 return 0;
3263
3264         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3265         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3266         crc = crc16(crc, (__u8 *)gdp, offset);
3267         offset += sizeof(gdp->bg_checksum); /* skip checksum */
3268         /* for checksum of struct ext4_group_desc do the rest...*/
3269         if (ext4_has_feature_64bit(sb) && offset < sbi->s_desc_size)
3270                 crc = crc16(crc, (__u8 *)gdp + offset,
3271                             sbi->s_desc_size - offset);
3272
3273 out:
3274         return cpu_to_le16(crc);
3275 }
3276
3277 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3278                                 struct ext4_group_desc *gdp)
3279 {
3280         if (ext4_has_group_desc_csum(sb) &&
3281             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3282                 return 0;
3283
3284         return 1;
3285 }
3286
3287 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3288                               struct ext4_group_desc *gdp)
3289 {
3290         if (!ext4_has_group_desc_csum(sb))
3291                 return;
3292         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3293 }
3294
3295 /* Called at mount-time, super-block is locked */
3296 static int ext4_check_descriptors(struct super_block *sb,
3297                                   ext4_fsblk_t sb_block,
3298                                   ext4_group_t *first_not_zeroed)
3299 {
3300         struct ext4_sb_info *sbi = EXT4_SB(sb);
3301         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3302         ext4_fsblk_t last_block;
3303         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3304         ext4_fsblk_t block_bitmap;
3305         ext4_fsblk_t inode_bitmap;
3306         ext4_fsblk_t inode_table;
3307         int flexbg_flag = 0;
3308         ext4_group_t i, grp = sbi->s_groups_count;
3309
3310         if (ext4_has_feature_flex_bg(sb))
3311                 flexbg_flag = 1;
3312
3313         ext4_debug("Checking group descriptors");
3314
3315         for (i = 0; i < sbi->s_groups_count; i++) {
3316                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3317
3318                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
3319                         last_block = ext4_blocks_count(sbi->s_es) - 1;
3320                 else
3321                         last_block = first_block +
3322                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
3323
3324                 if ((grp == sbi->s_groups_count) &&
3325                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3326                         grp = i;
3327
3328                 block_bitmap = ext4_block_bitmap(sb, gdp);
3329                 if (block_bitmap == sb_block) {
3330                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3331                                  "Block bitmap for group %u overlaps "
3332                                  "superblock", i);
3333                         if (!sb_rdonly(sb))
3334                                 return 0;
3335                 }
3336                 if (block_bitmap >= sb_block + 1 &&
3337                     block_bitmap <= last_bg_block) {
3338                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3339                                  "Block bitmap for group %u overlaps "
3340                                  "block group descriptors", i);
3341                         if (!sb_rdonly(sb))
3342                                 return 0;
3343                 }
3344                 if (block_bitmap < first_block || block_bitmap > last_block) {
3345                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3346                                "Block bitmap for group %u not in group "
3347                                "(block %llu)!", i, block_bitmap);
3348                         return 0;
3349                 }
3350                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
3351                 if (inode_bitmap == sb_block) {
3352                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3353                                  "Inode bitmap for group %u overlaps "
3354                                  "superblock", i);
3355                         if (!sb_rdonly(sb))
3356                                 return 0;
3357                 }
3358                 if (inode_bitmap >= sb_block + 1 &&
3359                     inode_bitmap <= last_bg_block) {
3360                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3361                                  "Inode bitmap for group %u overlaps "
3362                                  "block group descriptors", i);
3363                         if (!sb_rdonly(sb))
3364                                 return 0;
3365                 }
3366                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
3367                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3368                                "Inode bitmap for group %u not in group "
3369                                "(block %llu)!", i, inode_bitmap);
3370                         return 0;
3371                 }
3372                 inode_table = ext4_inode_table(sb, gdp);
3373                 if (inode_table == sb_block) {
3374                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3375                                  "Inode table for group %u overlaps "
3376                                  "superblock", i);
3377                         if (!sb_rdonly(sb))
3378                                 return 0;
3379                 }
3380                 if (inode_table >= sb_block + 1 &&
3381                     inode_table <= last_bg_block) {
3382                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3383                                  "Inode table for group %u overlaps "
3384                                  "block group descriptors", i);
3385                         if (!sb_rdonly(sb))
3386                                 return 0;
3387                 }
3388                 if (inode_table < first_block ||
3389                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
3390                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3391                                "Inode table for group %u not in group "
3392                                "(block %llu)!", i, inode_table);
3393                         return 0;
3394                 }
3395                 ext4_lock_group(sb, i);
3396                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3397                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3398                                  "Checksum for group %u failed (%u!=%u)",
3399                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3400                                      gdp)), le16_to_cpu(gdp->bg_checksum));
3401                         if (!sb_rdonly(sb)) {
3402                                 ext4_unlock_group(sb, i);
3403                                 return 0;
3404                         }
3405                 }
3406                 ext4_unlock_group(sb, i);
3407                 if (!flexbg_flag)
3408                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
3409         }
3410         if (NULL != first_not_zeroed)
3411                 *first_not_zeroed = grp;
3412         return 1;
3413 }
3414
3415 /*
3416  * Maximal extent format file size.
3417  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3418  * extent format containers, within a sector_t, and within i_blocks
3419  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3420  * so that won't be a limiting factor.
3421  *
3422  * However there is other limiting factor. We do store extents in the form
3423  * of starting block and length, hence the resulting length of the extent
3424  * covering maximum file size must fit into on-disk format containers as
3425  * well. Given that length is always by 1 unit bigger than max unit (because
3426  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3427  *
3428  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3429  */
3430 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3431 {
3432         loff_t res;
3433         loff_t upper_limit = MAX_LFS_FILESIZE;
3434
3435         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3436
3437         if (!has_huge_files) {
3438                 upper_limit = (1LL << 32) - 1;
3439
3440                 /* total blocks in file system block size */
3441                 upper_limit >>= (blkbits - 9);
3442                 upper_limit <<= blkbits;
3443         }
3444
3445         /*
3446          * 32-bit extent-start container, ee_block. We lower the maxbytes
3447          * by one fs block, so ee_len can cover the extent of maximum file
3448          * size
3449          */
3450         res = (1LL << 32) - 1;
3451         res <<= blkbits;
3452
3453         /* Sanity check against vm- & vfs- imposed limits */
3454         if (res > upper_limit)
3455                 res = upper_limit;
3456
3457         return res;
3458 }
3459
3460 /*
3461  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3462  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3463  * We need to be 1 filesystem block less than the 2^48 sector limit.
3464  */
3465 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3466 {
3467         loff_t upper_limit, res = EXT4_NDIR_BLOCKS;
3468         int meta_blocks;
3469         unsigned int ppb = 1 << (bits - 2);
3470
3471         /*
3472          * This is calculated to be the largest file size for a dense, block
3473          * mapped file such that the file's total number of 512-byte sectors,
3474          * including data and all indirect blocks, does not exceed (2^48 - 1).
3475          *
3476          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3477          * number of 512-byte sectors of the file.
3478          */
3479         if (!has_huge_files) {
3480                 /*
3481                  * !has_huge_files or implies that the inode i_block field
3482                  * represents total file blocks in 2^32 512-byte sectors ==
3483                  * size of vfs inode i_blocks * 8
3484                  */
3485                 upper_limit = (1LL << 32) - 1;
3486
3487                 /* total blocks in file system block size */
3488                 upper_limit >>= (bits - 9);
3489
3490         } else {
3491                 /*
3492                  * We use 48 bit ext4_inode i_blocks
3493                  * With EXT4_HUGE_FILE_FL set the i_blocks
3494                  * represent total number of blocks in
3495                  * file system block size
3496                  */
3497                 upper_limit = (1LL << 48) - 1;
3498
3499         }
3500
3501         /* Compute how many blocks we can address by block tree */
3502         res += ppb;
3503         res += ppb * ppb;
3504         res += ((loff_t)ppb) * ppb * ppb;
3505         /* Compute how many metadata blocks are needed */
3506         meta_blocks = 1;
3507         meta_blocks += 1 + ppb;
3508         meta_blocks += 1 + ppb + ppb * ppb;
3509         /* Does block tree limit file size? */
3510         if (res + meta_blocks <= upper_limit)
3511                 goto check_lfs;
3512
3513         res = upper_limit;
3514         /* How many metadata blocks are needed for addressing upper_limit? */
3515         upper_limit -= EXT4_NDIR_BLOCKS;
3516         /* indirect blocks */
3517         meta_blocks = 1;
3518         upper_limit -= ppb;
3519         /* double indirect blocks */
3520         if (upper_limit < ppb * ppb) {
3521                 meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb);
3522                 res -= meta_blocks;
3523                 goto check_lfs;
3524         }
3525         meta_blocks += 1 + ppb;
3526         upper_limit -= ppb * ppb;
3527         /* tripple indirect blocks for the rest */
3528         meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb) +
3529                 DIV_ROUND_UP_ULL(upper_limit, ppb*ppb);
3530         res -= meta_blocks;
3531 check_lfs:
3532         res <<= bits;
3533         if (res > MAX_LFS_FILESIZE)
3534                 res = MAX_LFS_FILESIZE;
3535
3536         return res;
3537 }
3538
3539 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3540                                    ext4_fsblk_t logical_sb_block, int nr)
3541 {
3542         struct ext4_sb_info *sbi = EXT4_SB(sb);
3543         ext4_group_t bg, first_meta_bg;
3544         int has_super = 0;
3545
3546         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3547
3548         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3549                 return logical_sb_block + nr + 1;
3550         bg = sbi->s_desc_per_block * nr;
3551         if (ext4_bg_has_super(sb, bg))
3552                 has_super = 1;
3553
3554         /*
3555          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3556          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3557          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3558          * compensate.
3559          */
3560         if (sb->s_blocksize == 1024 && nr == 0 &&
3561             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3562                 has_super++;
3563
3564         return (has_super + ext4_group_first_block_no(sb, bg));
3565 }
3566
3567 /**
3568  * ext4_get_stripe_size: Get the stripe size.
3569  * @sbi: In memory super block info
3570  *
3571  * If we have specified it via mount option, then
3572  * use the mount option value. If the value specified at mount time is
3573  * greater than the blocks per group use the super block value.
3574  * If the super block value is greater than blocks per group return 0.
3575  * Allocator needs it be less than blocks per group.
3576  *
3577  */
3578 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3579 {
3580         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3581         unsigned long stripe_width =
3582                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3583         int ret;
3584
3585         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3586                 ret = sbi->s_stripe;
3587         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3588                 ret = stripe_width;
3589         else if (stride && stride <= sbi->s_blocks_per_group)
3590                 ret = stride;
3591         else
3592                 ret = 0;
3593
3594         /*
3595          * If the stripe width is 1, this makes no sense and
3596          * we set it to 0 to turn off stripe handling code.
3597          */
3598         if (ret <= 1)
3599                 ret = 0;
3600
3601         return ret;
3602 }
3603
3604 /*
3605  * Check whether this filesystem can be mounted based on
3606  * the features present and the RDONLY/RDWR mount requested.
3607  * Returns 1 if this filesystem can be mounted as requested,
3608  * 0 if it cannot be.
3609  */
3610 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3611 {
3612         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3613                 ext4_msg(sb, KERN_ERR,
3614                         "Couldn't mount because of "
3615                         "unsupported optional features (%x)",
3616                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3617                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3618                 return 0;
3619         }
3620
3621 #if !IS_ENABLED(CONFIG_UNICODE)
3622         if (ext4_has_feature_casefold(sb)) {
3623                 ext4_msg(sb, KERN_ERR,
3624                          "Filesystem with casefold feature cannot be "
3625                          "mounted without CONFIG_UNICODE");
3626                 return 0;
3627         }
3628 #endif
3629
3630         if (readonly)
3631                 return 1;
3632
3633         if (ext4_has_feature_readonly(sb)) {
3634                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3635                 sb->s_flags |= SB_RDONLY;
3636                 return 1;
3637         }
3638
3639         /* Check that feature set is OK for a read-write mount */
3640         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3641                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3642                          "unsupported optional features (%x)",
3643                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3644                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3645                 return 0;
3646         }
3647         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3648                 ext4_msg(sb, KERN_ERR,
3649                          "Can't support bigalloc feature without "
3650                          "extents feature\n");
3651                 return 0;
3652         }
3653
3654 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3655         if (!readonly && (ext4_has_feature_quota(sb) ||
3656                           ext4_has_feature_project(sb))) {
3657                 ext4_msg(sb, KERN_ERR,
3658                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3659                 return 0;
3660         }
3661 #endif  /* CONFIG_QUOTA */
3662         return 1;
3663 }
3664
3665 /*
3666  * This function is called once a day if we have errors logged
3667  * on the file system
3668  */
3669 static void print_daily_error_info(struct timer_list *t)
3670 {
3671         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3672         struct super_block *sb = sbi->s_sb;
3673         struct ext4_super_block *es = sbi->s_es;
3674
3675         if (es->s_error_count)
3676                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3677                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3678                          le32_to_cpu(es->s_error_count));
3679         if (es->s_first_error_time) {
3680                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3681                        sb->s_id,
3682                        ext4_get_tstamp(es, s_first_error_time),
3683                        (int) sizeof(es->s_first_error_func),
3684                        es->s_first_error_func,
3685                        le32_to_cpu(es->s_first_error_line));
3686                 if (es->s_first_error_ino)
3687                         printk(KERN_CONT ": inode %u",
3688                                le32_to_cpu(es->s_first_error_ino));
3689                 if (es->s_first_error_block)
3690                         printk(KERN_CONT ": block %llu", (unsigned long long)
3691                                le64_to_cpu(es->s_first_error_block));
3692                 printk(KERN_CONT "\n");
3693         }
3694         if (es->s_last_error_time) {
3695                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3696                        sb->s_id,
3697                        ext4_get_tstamp(es, s_last_error_time),
3698                        (int) sizeof(es->s_last_error_func),
3699                        es->s_last_error_func,
3700                        le32_to_cpu(es->s_last_error_line));
3701                 if (es->s_last_error_ino)
3702                         printk(KERN_CONT ": inode %u",
3703                                le32_to_cpu(es->s_last_error_ino));
3704                 if (es->s_last_error_block)
3705                         printk(KERN_CONT ": block %llu", (unsigned long long)
3706                                le64_to_cpu(es->s_last_error_block));
3707                 printk(KERN_CONT "\n");
3708         }
3709         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3710 }
3711
3712 /* Find next suitable group and run ext4_init_inode_table */
3713 static int ext4_run_li_request(struct ext4_li_request *elr)
3714 {
3715         struct ext4_group_desc *gdp = NULL;
3716         struct super_block *sb = elr->lr_super;
3717         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3718         ext4_group_t group = elr->lr_next_group;
3719         unsigned int prefetch_ios = 0;
3720         int ret = 0;
3721         int nr = EXT4_SB(sb)->s_mb_prefetch;
3722         u64 start_time;
3723
3724         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3725                 elr->lr_next_group = ext4_mb_prefetch(sb, group, nr, &prefetch_ios);
3726                 ext4_mb_prefetch_fini(sb, elr->lr_next_group, nr);
3727                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group, nr);
3728                 if (group >= elr->lr_next_group) {
3729                         ret = 1;
3730                         if (elr->lr_first_not_zeroed != ngroups &&
3731                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3732                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3733                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3734                                 ret = 0;
3735                         }
3736                 }
3737                 return ret;
3738         }
3739
3740         for (; group < ngroups; group++) {
3741                 gdp = ext4_get_group_desc(sb, group, NULL);
3742                 if (!gdp) {
3743                         ret = 1;
3744                         break;
3745                 }
3746
3747                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3748                         break;
3749         }
3750
3751         if (group >= ngroups)
3752                 ret = 1;
3753
3754         if (!ret) {
3755                 start_time = ktime_get_real_ns();
3756                 ret = ext4_init_inode_table(sb, group,
3757                                             elr->lr_timeout ? 0 : 1);
3758                 trace_ext4_lazy_itable_init(sb, group);
3759                 if (elr->lr_timeout == 0) {
3760                         elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3761                                 EXT4_SB(elr->lr_super)->s_li_wait_mult);
3762                 }
3763                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3764                 elr->lr_next_group = group + 1;
3765         }
3766         return ret;
3767 }
3768
3769 /*
3770  * Remove lr_request from the list_request and free the
3771  * request structure. Should be called with li_list_mtx held
3772  */
3773 static void ext4_remove_li_request(struct ext4_li_request *elr)
3774 {
3775         if (!elr)
3776                 return;
3777
3778         list_del(&elr->lr_request);
3779         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3780         kfree(elr);
3781 }
3782
3783 static void ext4_unregister_li_request(struct super_block *sb)
3784 {
3785         mutex_lock(&ext4_li_mtx);
3786         if (!ext4_li_info) {
3787                 mutex_unlock(&ext4_li_mtx);
3788                 return;
3789         }
3790
3791         mutex_lock(&ext4_li_info->li_list_mtx);
3792         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3793         mutex_unlock(&ext4_li_info->li_list_mtx);
3794         mutex_unlock(&ext4_li_mtx);
3795 }
3796
3797 static struct task_struct *ext4_lazyinit_task;
3798
3799 /*
3800  * This is the function where ext4lazyinit thread lives. It walks
3801  * through the request list searching for next scheduled filesystem.
3802  * When such a fs is found, run the lazy initialization request
3803  * (ext4_rn_li_request) and keep track of the time spend in this
3804  * function. Based on that time we compute next schedule time of
3805  * the request. When walking through the list is complete, compute
3806  * next waking time and put itself into sleep.
3807  */
3808 static int ext4_lazyinit_thread(void *arg)
3809 {
3810         struct ext4_lazy_init *eli = arg;
3811         struct list_head *pos, *n;
3812         struct ext4_li_request *elr;
3813         unsigned long next_wakeup, cur;
3814
3815         BUG_ON(NULL == eli);
3816         set_freezable();
3817
3818 cont_thread:
3819         while (true) {
3820                 next_wakeup = MAX_JIFFY_OFFSET;
3821
3822                 mutex_lock(&eli->li_list_mtx);
3823                 if (list_empty(&eli->li_request_list)) {
3824                         mutex_unlock(&eli->li_list_mtx);
3825                         goto exit_thread;
3826                 }
3827                 list_for_each_safe(pos, n, &eli->li_request_list) {
3828                         int err = 0;
3829                         int progress = 0;
3830                         elr = list_entry(pos, struct ext4_li_request,
3831                                          lr_request);
3832
3833                         if (time_before(jiffies, elr->lr_next_sched)) {
3834                                 if (time_before(elr->lr_next_sched, next_wakeup))
3835                                         next_wakeup = elr->lr_next_sched;
3836                                 continue;
3837                         }
3838                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3839                                 if (sb_start_write_trylock(elr->lr_super)) {
3840                                         progress = 1;
3841                                         /*
3842                                          * We hold sb->s_umount, sb can not
3843                                          * be removed from the list, it is
3844                                          * now safe to drop li_list_mtx
3845                                          */
3846                                         mutex_unlock(&eli->li_list_mtx);
3847                                         err = ext4_run_li_request(elr);
3848                                         sb_end_write(elr->lr_super);
3849                                         mutex_lock(&eli->li_list_mtx);
3850                                         n = pos->next;
3851                                 }
3852                                 up_read((&elr->lr_super->s_umount));
3853                         }
3854                         /* error, remove the lazy_init job */
3855                         if (err) {
3856                                 ext4_remove_li_request(elr);
3857                                 continue;
3858                         }
3859                         if (!progress) {
3860                                 elr->lr_next_sched = jiffies +
3861                                         get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3862                         }
3863                         if (time_before(elr->lr_next_sched, next_wakeup))
3864                                 next_wakeup = elr->lr_next_sched;
3865                 }
3866                 mutex_unlock(&eli->li_list_mtx);
3867
3868                 try_to_freeze();
3869
3870                 cur = jiffies;
3871                 if ((time_after_eq(cur, next_wakeup)) ||
3872                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3873                         cond_resched();
3874                         continue;
3875                 }
3876
3877                 schedule_timeout_interruptible(next_wakeup - cur);
3878
3879                 if (kthread_should_stop()) {
3880                         ext4_clear_request_list();
3881                         goto exit_thread;
3882                 }
3883         }
3884
3885 exit_thread:
3886         /*
3887          * It looks like the request list is empty, but we need
3888          * to check it under the li_list_mtx lock, to prevent any
3889          * additions into it, and of course we should lock ext4_li_mtx
3890          * to atomically free the list and ext4_li_info, because at
3891          * this point another ext4 filesystem could be registering
3892          * new one.
3893          */
3894         mutex_lock(&ext4_li_mtx);
3895         mutex_lock(&eli->li_list_mtx);
3896         if (!list_empty(&eli->li_request_list)) {
3897                 mutex_unlock(&eli->li_list_mtx);
3898                 mutex_unlock(&ext4_li_mtx);
3899                 goto cont_thread;
3900         }
3901         mutex_unlock(&eli->li_list_mtx);
3902         kfree(ext4_li_info);
3903         ext4_li_info = NULL;
3904         mutex_unlock(&ext4_li_mtx);
3905
3906         return 0;
3907 }
3908
3909 static void ext4_clear_request_list(void)
3910 {
3911         struct list_head *pos, *n;
3912         struct ext4_li_request *elr;
3913
3914         mutex_lock(&ext4_li_info->li_list_mtx);
3915         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3916                 elr = list_entry(pos, struct ext4_li_request,
3917                                  lr_request);
3918                 ext4_remove_li_request(elr);
3919         }
3920         mutex_unlock(&ext4_li_info->li_list_mtx);
3921 }
3922
3923 static int ext4_run_lazyinit_thread(void)
3924 {
3925         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3926                                          ext4_li_info, "ext4lazyinit");
3927         if (IS_ERR(ext4_lazyinit_task)) {
3928                 int err = PTR_ERR(ext4_lazyinit_task);
3929                 ext4_clear_request_list();
3930                 kfree(ext4_li_info);
3931                 ext4_li_info = NULL;
3932                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3933                                  "initialization thread\n",
3934                                  err);
3935                 return err;
3936         }
3937         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3938         return 0;
3939 }
3940
3941 /*
3942  * Check whether it make sense to run itable init. thread or not.
3943  * If there is at least one uninitialized inode table, return
3944  * corresponding group number, else the loop goes through all
3945  * groups and return total number of groups.
3946  */
3947 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3948 {
3949         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3950         struct ext4_group_desc *gdp = NULL;
3951
3952         if (!ext4_has_group_desc_csum(sb))
3953                 return ngroups;
3954
3955         for (group = 0; group < ngroups; group++) {
3956                 gdp = ext4_get_group_desc(sb, group, NULL);
3957                 if (!gdp)
3958                         continue;
3959
3960                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3961                         break;
3962         }
3963
3964         return group;
3965 }
3966
3967 static int ext4_li_info_new(void)
3968 {
3969         struct ext4_lazy_init *eli = NULL;
3970
3971         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3972         if (!eli)
3973                 return -ENOMEM;
3974
3975         INIT_LIST_HEAD(&eli->li_request_list);
3976         mutex_init(&eli->li_list_mtx);
3977
3978         eli->li_state |= EXT4_LAZYINIT_QUIT;
3979
3980         ext4_li_info = eli;
3981
3982         return 0;
3983 }
3984
3985 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3986                                             ext4_group_t start)
3987 {
3988         struct ext4_li_request *elr;
3989
3990         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3991         if (!elr)
3992                 return NULL;
3993
3994         elr->lr_super = sb;
3995         elr->lr_first_not_zeroed = start;
3996         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3997                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3998                 elr->lr_next_group = start;
3999         } else {
4000                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
4001         }
4002
4003         /*
4004          * Randomize first schedule time of the request to
4005          * spread the inode table initialization requests
4006          * better.
4007          */
4008         elr->lr_next_sched = jiffies + get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
4009         return elr;
4010 }
4011
4012 int ext4_register_li_request(struct super_block *sb,
4013                              ext4_group_t first_not_zeroed)
4014 {
4015         struct ext4_sb_info *sbi = EXT4_SB(sb);
4016         struct ext4_li_request *elr = NULL;
4017         ext4_group_t ngroups = sbi->s_groups_count;
4018         int ret = 0;
4019
4020         mutex_lock(&ext4_li_mtx);
4021         if (sbi->s_li_request != NULL) {
4022                 /*
4023                  * Reset timeout so it can be computed again, because
4024                  * s_li_wait_mult might have changed.
4025                  */
4026                 sbi->s_li_request->lr_timeout = 0;
4027                 goto out;
4028         }
4029
4030         if (sb_rdonly(sb) ||
4031             (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
4032              (first_not_zeroed == ngroups || !test_opt(sb, INIT_INODE_TABLE))))
4033                 goto out;
4034
4035         elr = ext4_li_request_new(sb, first_not_zeroed);
4036         if (!elr) {
4037                 ret = -ENOMEM;
4038                 goto out;
4039         }
4040
4041         if (NULL == ext4_li_info) {
4042                 ret = ext4_li_info_new();
4043                 if (ret)
4044                         goto out;
4045         }
4046
4047         mutex_lock(&ext4_li_info->li_list_mtx);
4048         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
4049         mutex_unlock(&ext4_li_info->li_list_mtx);
4050
4051         sbi->s_li_request = elr;
4052         /*
4053          * set elr to NULL here since it has been inserted to
4054          * the request_list and the removal and free of it is
4055          * handled by ext4_clear_request_list from now on.
4056          */
4057         elr = NULL;
4058
4059         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
4060                 ret = ext4_run_lazyinit_thread();
4061                 if (ret)
4062                         goto out;
4063         }
4064 out:
4065         mutex_unlock(&ext4_li_mtx);
4066         if (ret)
4067                 kfree(elr);
4068         return ret;
4069 }
4070
4071 /*
4072  * We do not need to lock anything since this is called on
4073  * module unload.
4074  */
4075 static void ext4_destroy_lazyinit_thread(void)
4076 {
4077         /*
4078          * If thread exited earlier
4079          * there's nothing to be done.
4080          */
4081         if (!ext4_li_info || !ext4_lazyinit_task)
4082                 return;
4083
4084         kthread_stop(ext4_lazyinit_task);
4085 }
4086
4087 static int set_journal_csum_feature_set(struct super_block *sb)
4088 {
4089         int ret = 1;
4090         int compat, incompat;
4091         struct ext4_sb_info *sbi = EXT4_SB(sb);
4092
4093         if (ext4_has_metadata_csum(sb)) {
4094                 /* journal checksum v3 */
4095                 compat = 0;
4096                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4097         } else {
4098                 /* journal checksum v1 */
4099                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4100                 incompat = 0;
4101         }
4102
4103         jbd2_journal_clear_features(sbi->s_journal,
4104                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4105                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4106                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
4107         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4108                 ret = jbd2_journal_set_features(sbi->s_journal,
4109                                 compat, 0,
4110                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4111                                 incompat);
4112         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4113                 ret = jbd2_journal_set_features(sbi->s_journal,
4114                                 compat, 0,
4115                                 incompat);
4116                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4117                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4118         } else {
4119                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4120                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4121         }
4122
4123         return ret;
4124 }
4125
4126 /*
4127  * Note: calculating the overhead so we can be compatible with
4128  * historical BSD practice is quite difficult in the face of
4129  * clusters/bigalloc.  This is because multiple metadata blocks from
4130  * different block group can end up in the same allocation cluster.
4131  * Calculating the exact overhead in the face of clustered allocation
4132  * requires either O(all block bitmaps) in memory or O(number of block
4133  * groups**2) in time.  We will still calculate the superblock for
4134  * older file systems --- and if we come across with a bigalloc file
4135  * system with zero in s_overhead_clusters the estimate will be close to
4136  * correct especially for very large cluster sizes --- but for newer
4137  * file systems, it's better to calculate this figure once at mkfs
4138  * time, and store it in the superblock.  If the superblock value is
4139  * present (even for non-bigalloc file systems), we will use it.
4140  */
4141 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4142                           char *buf)
4143 {
4144         struct ext4_sb_info     *sbi = EXT4_SB(sb);
4145         struct ext4_group_desc  *gdp;
4146         ext4_fsblk_t            first_block, last_block, b;
4147         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
4148         int                     s, j, count = 0;
4149         int                     has_super = ext4_bg_has_super(sb, grp);
4150
4151         if (!ext4_has_feature_bigalloc(sb))
4152                 return (has_super + ext4_bg_num_gdb(sb, grp) +
4153                         (has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
4154                         sbi->s_itb_per_group + 2);
4155
4156         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4157                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
4158         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4159         for (i = 0; i < ngroups; i++) {
4160                 gdp = ext4_get_group_desc(sb, i, NULL);
4161                 b = ext4_block_bitmap(sb, gdp);
4162                 if (b >= first_block && b <= last_block) {
4163                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4164                         count++;
4165                 }
4166                 b = ext4_inode_bitmap(sb, gdp);
4167                 if (b >= first_block && b <= last_block) {
4168                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4169                         count++;
4170                 }
4171                 b = ext4_inode_table(sb, gdp);
4172                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4173                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4174                                 int c = EXT4_B2C(sbi, b - first_block);
4175                                 ext4_set_bit(c, buf);
4176                                 count++;
4177                         }
4178                 if (i != grp)
4179                         continue;
4180                 s = 0;
4181                 if (ext4_bg_has_super(sb, grp)) {
4182                         ext4_set_bit(s++, buf);
4183                         count++;
4184                 }
4185                 j = ext4_bg_num_gdb(sb, grp);
4186                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4187                         ext4_error(sb, "Invalid number of block group "
4188                                    "descriptor blocks: %d", j);
4189                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4190                 }
4191                 count += j;
4192                 for (; j > 0; j--)
4193                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4194         }
4195         if (!count)
4196                 return 0;
4197         return EXT4_CLUSTERS_PER_GROUP(sb) -
4198                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4199 }
4200
4201 /*
4202  * Compute the overhead and stash it in sbi->s_overhead
4203  */
4204 int ext4_calculate_overhead(struct super_block *sb)
4205 {
4206         struct ext4_sb_info *sbi = EXT4_SB(sb);
4207         struct ext4_super_block *es = sbi->s_es;
4208         struct inode *j_inode;
4209         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4210         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4211         ext4_fsblk_t overhead = 0;
4212         char *buf = (char *) get_zeroed_page(GFP_NOFS);
4213
4214         if (!buf)
4215                 return -ENOMEM;
4216
4217         /*
4218          * Compute the overhead (FS structures).  This is constant
4219          * for a given filesystem unless the number of block groups
4220          * changes so we cache the previous value until it does.
4221          */
4222
4223         /*
4224          * All of the blocks before first_data_block are overhead
4225          */
4226         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4227
4228         /*
4229          * Add the overhead found in each block group
4230          */
4231         for (i = 0; i < ngroups; i++) {
4232                 int blks;
4233
4234                 blks = count_overhead(sb, i, buf);
4235                 overhead += blks;
4236                 if (blks)
4237                         memset(buf, 0, PAGE_SIZE);
4238                 cond_resched();
4239         }
4240
4241         /*
4242          * Add the internal journal blocks whether the journal has been
4243          * loaded or not
4244          */
4245         if (sbi->s_journal && !sbi->s_journal_bdev_handle)
4246                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4247         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4248                 /* j_inum for internal journal is non-zero */
4249                 j_inode = ext4_get_journal_inode(sb, j_inum);
4250                 if (!IS_ERR(j_inode)) {
4251                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4252                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
4253                         iput(j_inode);
4254                 } else {
4255                         ext4_msg(sb, KERN_ERR, "can't get journal size");
4256                 }
4257         }
4258         sbi->s_overhead = overhead;
4259         smp_wmb();
4260         free_page((unsigned long) buf);
4261         return 0;
4262 }
4263
4264 static void ext4_set_resv_clusters(struct super_block *sb)
4265 {
4266         ext4_fsblk_t resv_clusters;
4267         struct ext4_sb_info *sbi = EXT4_SB(sb);
4268
4269         /*
4270          * There's no need to reserve anything when we aren't using extents.
4271          * The space estimates are exact, there are no unwritten extents,
4272          * hole punching doesn't need new metadata... This is needed especially
4273          * to keep ext2/3 backward compatibility.
4274          */
4275         if (!ext4_has_feature_extents(sb))
4276                 return;
4277         /*
4278          * By default we reserve 2% or 4096 clusters, whichever is smaller.
4279          * This should cover the situations where we can not afford to run
4280          * out of space like for example punch hole, or converting
4281          * unwritten extents in delalloc path. In most cases such
4282          * allocation would require 1, or 2 blocks, higher numbers are
4283          * very rare.
4284          */
4285         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4286                          sbi->s_cluster_bits);
4287
4288         do_div(resv_clusters, 50);
4289         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4290
4291         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4292 }
4293
4294 static const char *ext4_quota_mode(struct super_block *sb)
4295 {
4296 #ifdef CONFIG_QUOTA
4297         if (!ext4_quota_capable(sb))
4298                 return "none";
4299
4300         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4301                 return "journalled";
4302         else
4303                 return "writeback";
4304 #else
4305         return "disabled";
4306 #endif
4307 }
4308
4309 static void ext4_setup_csum_trigger(struct super_block *sb,
4310                                     enum ext4_journal_trigger_type type,
4311                                     void (*trigger)(
4312                                         struct jbd2_buffer_trigger_type *type,
4313                                         struct buffer_head *bh,
4314                                         void *mapped_data,
4315                                         size_t size))
4316 {
4317         struct ext4_sb_info *sbi = EXT4_SB(sb);
4318
4319         sbi->s_journal_triggers[type].sb = sb;
4320         sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4321 }
4322
4323 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4324 {
4325         if (!sbi)
4326                 return;
4327
4328         kfree(sbi->s_blockgroup_lock);
4329         fs_put_dax(sbi->s_daxdev, NULL);
4330         kfree(sbi);
4331 }
4332
4333 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4334 {
4335         struct ext4_sb_info *sbi;
4336
4337         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4338         if (!sbi)
4339                 return NULL;
4340
4341         sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
4342                                            NULL, NULL);
4343
4344         sbi->s_blockgroup_lock =
4345                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4346
4347         if (!sbi->s_blockgroup_lock)
4348                 goto err_out;
4349
4350         sb->s_fs_info = sbi;
4351         sbi->s_sb = sb;
4352         return sbi;
4353 err_out:
4354         fs_put_dax(sbi->s_daxdev, NULL);
4355         kfree(sbi);
4356         return NULL;
4357 }
4358
4359 static void ext4_set_def_opts(struct super_block *sb,
4360                               struct ext4_super_block *es)
4361 {
4362         unsigned long def_mount_opts;
4363
4364         /* Set defaults before we parse the mount options */
4365         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4366         set_opt(sb, INIT_INODE_TABLE);
4367         if (def_mount_opts & EXT4_DEFM_DEBUG)
4368                 set_opt(sb, DEBUG);
4369         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4370                 set_opt(sb, GRPID);
4371         if (def_mount_opts & EXT4_DEFM_UID16)
4372                 set_opt(sb, NO_UID32);
4373         /* xattr user namespace & acls are now defaulted on */
4374         set_opt(sb, XATTR_USER);
4375 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4376         set_opt(sb, POSIX_ACL);
4377 #endif
4378         if (ext4_has_feature_fast_commit(sb))
4379                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4380         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4381         if (ext4_has_metadata_csum(sb))
4382                 set_opt(sb, JOURNAL_CHECKSUM);
4383
4384         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4385                 set_opt(sb, JOURNAL_DATA);
4386         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4387                 set_opt(sb, ORDERED_DATA);
4388         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4389                 set_opt(sb, WRITEBACK_DATA);
4390
4391         if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_PANIC)
4392                 set_opt(sb, ERRORS_PANIC);
4393         else if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_CONTINUE)
4394                 set_opt(sb, ERRORS_CONT);
4395         else
4396                 set_opt(sb, ERRORS_RO);
4397         /* block_validity enabled by default; disable with noblock_validity */
4398         set_opt(sb, BLOCK_VALIDITY);
4399         if (def_mount_opts & EXT4_DEFM_DISCARD)
4400                 set_opt(sb, DISCARD);
4401
4402         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4403                 set_opt(sb, BARRIER);
4404
4405         /*
4406          * enable delayed allocation by default
4407          * Use -o nodelalloc to turn it off
4408          */
4409         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4410             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4411                 set_opt(sb, DELALLOC);
4412
4413         if (sb->s_blocksize == PAGE_SIZE)
4414                 set_opt(sb, DIOREAD_NOLOCK);
4415 }
4416
4417 static int ext4_handle_clustersize(struct super_block *sb)
4418 {
4419         struct ext4_sb_info *sbi = EXT4_SB(sb);
4420         struct ext4_super_block *es = sbi->s_es;
4421         int clustersize;
4422
4423         /* Handle clustersize */
4424         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4425         if (ext4_has_feature_bigalloc(sb)) {
4426                 if (clustersize < sb->s_blocksize) {
4427                         ext4_msg(sb, KERN_ERR,
4428                                  "cluster size (%d) smaller than "
4429                                  "block size (%lu)", clustersize, sb->s_blocksize);
4430                         return -EINVAL;
4431                 }
4432                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4433                         le32_to_cpu(es->s_log_block_size);
4434                 sbi->s_clusters_per_group =
4435                         le32_to_cpu(es->s_clusters_per_group);
4436                 if (sbi->s_clusters_per_group > sb->s_blocksize * 8) {
4437                         ext4_msg(sb, KERN_ERR,
4438                                  "#clusters per group too big: %lu",
4439                                  sbi->s_clusters_per_group);
4440                         return -EINVAL;
4441                 }
4442                 if (sbi->s_blocks_per_group !=
4443                     (sbi->s_clusters_per_group * (clustersize / sb->s_blocksize))) {
4444                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4445                                  "clusters per group (%lu) inconsistent",
4446                                  sbi->s_blocks_per_group,
4447                                  sbi->s_clusters_per_group);
4448                         return -EINVAL;
4449                 }
4450         } else {
4451                 if (clustersize != sb->s_blocksize) {
4452                         ext4_msg(sb, KERN_ERR,
4453                                  "fragment/cluster size (%d) != "
4454                                  "block size (%lu)", clustersize, sb->s_blocksize);
4455                         return -EINVAL;
4456                 }
4457                 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
4458                         ext4_msg(sb, KERN_ERR,
4459                                  "#blocks per group too big: %lu",
4460                                  sbi->s_blocks_per_group);
4461                         return -EINVAL;
4462                 }
4463                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4464                 sbi->s_cluster_bits = 0;
4465         }
4466         sbi->s_cluster_ratio = clustersize / sb->s_blocksize;
4467
4468         /* Do we have standard group size of clustersize * 8 blocks ? */
4469         if (sbi->s_blocks_per_group == clustersize << 3)
4470                 set_opt2(sb, STD_GROUP_SIZE);
4471
4472         return 0;
4473 }
4474
4475 static void ext4_fast_commit_init(struct super_block *sb)
4476 {
4477         struct ext4_sb_info *sbi = EXT4_SB(sb);
4478
4479         /* Initialize fast commit stuff */
4480         atomic_set(&sbi->s_fc_subtid, 0);
4481         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4482         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4483         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4484         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4485         sbi->s_fc_bytes = 0;
4486         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4487         sbi->s_fc_ineligible_tid = 0;
4488         spin_lock_init(&sbi->s_fc_lock);
4489         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4490         sbi->s_fc_replay_state.fc_regions = NULL;
4491         sbi->s_fc_replay_state.fc_regions_size = 0;
4492         sbi->s_fc_replay_state.fc_regions_used = 0;
4493         sbi->s_fc_replay_state.fc_regions_valid = 0;
4494         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4495         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4496         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4497 }
4498
4499 static int ext4_inode_info_init(struct super_block *sb,
4500                                 struct ext4_super_block *es)
4501 {
4502         struct ext4_sb_info *sbi = EXT4_SB(sb);
4503
4504         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4505                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4506                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4507         } else {
4508                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4509                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4510                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4511                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4512                                  sbi->s_first_ino);
4513                         return -EINVAL;
4514                 }
4515                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4516                     (!is_power_of_2(sbi->s_inode_size)) ||
4517                     (sbi->s_inode_size > sb->s_blocksize)) {
4518                         ext4_msg(sb, KERN_ERR,
4519                                "unsupported inode size: %d",
4520                                sbi->s_inode_size);
4521                         ext4_msg(sb, KERN_ERR, "blocksize: %lu", sb->s_blocksize);
4522                         return -EINVAL;
4523                 }
4524                 /*
4525                  * i_atime_extra is the last extra field available for
4526                  * [acm]times in struct ext4_inode. Checking for that
4527                  * field should suffice to ensure we have extra space
4528                  * for all three.
4529                  */
4530                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4531                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4532                         sb->s_time_gran = 1;
4533                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4534                 } else {
4535                         sb->s_time_gran = NSEC_PER_SEC;
4536                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4537                 }
4538                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4539         }
4540
4541         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4542                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4543                         EXT4_GOOD_OLD_INODE_SIZE;
4544                 if (ext4_has_feature_extra_isize(sb)) {
4545                         unsigned v, max = (sbi->s_inode_size -
4546                                            EXT4_GOOD_OLD_INODE_SIZE);
4547
4548                         v = le16_to_cpu(es->s_want_extra_isize);
4549                         if (v > max) {
4550                                 ext4_msg(sb, KERN_ERR,
4551                                          "bad s_want_extra_isize: %d", v);
4552                                 return -EINVAL;
4553                         }
4554                         if (sbi->s_want_extra_isize < v)
4555                                 sbi->s_want_extra_isize = v;
4556
4557                         v = le16_to_cpu(es->s_min_extra_isize);
4558                         if (v > max) {
4559                                 ext4_msg(sb, KERN_ERR,
4560                                          "bad s_min_extra_isize: %d", v);
4561                                 return -EINVAL;
4562                         }
4563                         if (sbi->s_want_extra_isize < v)
4564                                 sbi->s_want_extra_isize = v;
4565                 }
4566         }
4567
4568         return 0;
4569 }
4570
4571 #if IS_ENABLED(CONFIG_UNICODE)
4572 static int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4573 {
4574         const struct ext4_sb_encodings *encoding_info;
4575         struct unicode_map *encoding;
4576         __u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4577
4578         if (!ext4_has_feature_casefold(sb) || sb->s_encoding)
4579                 return 0;
4580
4581         encoding_info = ext4_sb_read_encoding(es);
4582         if (!encoding_info) {
4583                 ext4_msg(sb, KERN_ERR,
4584                         "Encoding requested by superblock is unknown");
4585                 return -EINVAL;
4586         }
4587
4588         encoding = utf8_load(encoding_info->version);
4589         if (IS_ERR(encoding)) {
4590                 ext4_msg(sb, KERN_ERR,
4591                         "can't mount with superblock charset: %s-%u.%u.%u "
4592                         "not supported by the kernel. flags: 0x%x.",
4593                         encoding_info->name,
4594                         unicode_major(encoding_info->version),
4595                         unicode_minor(encoding_info->version),
4596                         unicode_rev(encoding_info->version),
4597                         encoding_flags);
4598                 return -EINVAL;
4599         }
4600         ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4601                 "%s-%u.%u.%u with flags 0x%hx", encoding_info->name,
4602                 unicode_major(encoding_info->version),
4603                 unicode_minor(encoding_info->version),
4604                 unicode_rev(encoding_info->version),
4605                 encoding_flags);
4606
4607         sb->s_encoding = encoding;
4608         sb->s_encoding_flags = encoding_flags;
4609
4610         return 0;
4611 }
4612 #else
4613 static inline int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4614 {
4615         return 0;
4616 }
4617 #endif
4618
4619 static int ext4_init_metadata_csum(struct super_block *sb, struct ext4_super_block *es)
4620 {
4621         struct ext4_sb_info *sbi = EXT4_SB(sb);
4622
4623         /* Warn if metadata_csum and gdt_csum are both set. */
4624         if (ext4_has_feature_metadata_csum(sb) &&
4625             ext4_has_feature_gdt_csum(sb))
4626                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4627                              "redundant flags; please run fsck.");
4628
4629         /* Check for a known checksum algorithm */
4630         if (!ext4_verify_csum_type(sb, es)) {
4631                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4632                          "unknown checksum algorithm.");
4633                 return -EINVAL;
4634         }
4635         ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4636                                 ext4_orphan_file_block_trigger);
4637
4638         /* Load the checksum driver */
4639         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4640         if (IS_ERR(sbi->s_chksum_driver)) {
4641                 int ret = PTR_ERR(sbi->s_chksum_driver);
4642                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4643                 sbi->s_chksum_driver = NULL;
4644                 return ret;
4645         }
4646
4647         /* Check superblock checksum */
4648         if (!ext4_superblock_csum_verify(sb, es)) {
4649                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4650                          "invalid superblock checksum.  Run e2fsck?");
4651                 return -EFSBADCRC;
4652         }
4653
4654         /* Precompute checksum seed for all metadata */
4655         if (ext4_has_feature_csum_seed(sb))
4656                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4657         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4658                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4659                                                sizeof(es->s_uuid));
4660         return 0;
4661 }
4662
4663 static int ext4_check_feature_compatibility(struct super_block *sb,
4664                                             struct ext4_super_block *es,
4665                                             int silent)
4666 {
4667         struct ext4_sb_info *sbi = EXT4_SB(sb);
4668
4669         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4670             (ext4_has_compat_features(sb) ||
4671              ext4_has_ro_compat_features(sb) ||
4672              ext4_has_incompat_features(sb)))
4673                 ext4_msg(sb, KERN_WARNING,
4674                        "feature flags set on rev 0 fs, "
4675                        "running e2fsck is recommended");
4676
4677         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4678                 set_opt2(sb, HURD_COMPAT);
4679                 if (ext4_has_feature_64bit(sb)) {
4680                         ext4_msg(sb, KERN_ERR,
4681                                  "The Hurd can't support 64-bit file systems");
4682                         return -EINVAL;
4683                 }
4684
4685                 /*
4686                  * ea_inode feature uses l_i_version field which is not
4687                  * available in HURD_COMPAT mode.
4688                  */
4689                 if (ext4_has_feature_ea_inode(sb)) {
4690                         ext4_msg(sb, KERN_ERR,
4691                                  "ea_inode feature is not supported for Hurd");
4692                         return -EINVAL;
4693                 }
4694         }
4695
4696         if (IS_EXT2_SB(sb)) {
4697                 if (ext2_feature_set_ok(sb))
4698                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4699                                  "using the ext4 subsystem");
4700                 else {
4701                         /*
4702                          * If we're probing be silent, if this looks like
4703                          * it's actually an ext[34] filesystem.
4704                          */
4705                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4706                                 return -EINVAL;
4707                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4708                                  "to feature incompatibilities");
4709                         return -EINVAL;
4710                 }
4711         }
4712
4713         if (IS_EXT3_SB(sb)) {
4714                 if (ext3_feature_set_ok(sb))
4715                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4716                                  "using the ext4 subsystem");
4717                 else {
4718                         /*
4719                          * If we're probing be silent, if this looks like
4720                          * it's actually an ext4 filesystem.
4721                          */
4722                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4723                                 return -EINVAL;
4724                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4725                                  "to feature incompatibilities");
4726                         return -EINVAL;
4727                 }
4728         }
4729
4730         /*
4731          * Check feature flags regardless of the revision level, since we
4732          * previously didn't change the revision level when setting the flags,
4733          * so there is a chance incompat flags are set on a rev 0 filesystem.
4734          */
4735         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4736                 return -EINVAL;
4737
4738         if (sbi->s_daxdev) {
4739                 if (sb->s_blocksize == PAGE_SIZE)
4740                         set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4741                 else
4742                         ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
4743         }
4744
4745         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4746                 if (ext4_has_feature_inline_data(sb)) {
4747                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4748                                         " that may contain inline data");
4749                         return -EINVAL;
4750                 }
4751                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4752                         ext4_msg(sb, KERN_ERR,
4753                                 "DAX unsupported by block device.");
4754                         return -EINVAL;
4755                 }
4756         }
4757
4758         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4759                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4760                          es->s_encryption_level);
4761                 return -EINVAL;
4762         }
4763
4764         return 0;
4765 }
4766
4767 static int ext4_check_geometry(struct super_block *sb,
4768                                struct ext4_super_block *es)
4769 {
4770         struct ext4_sb_info *sbi = EXT4_SB(sb);
4771         __u64 blocks_count;
4772         int err;
4773
4774         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (sb->s_blocksize / 4)) {
4775                 ext4_msg(sb, KERN_ERR,
4776                          "Number of reserved GDT blocks insanely large: %d",
4777                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4778                 return -EINVAL;
4779         }
4780         /*
4781          * Test whether we have more sectors than will fit in sector_t,
4782          * and whether the max offset is addressable by the page cache.
4783          */
4784         err = generic_check_addressable(sb->s_blocksize_bits,
4785                                         ext4_blocks_count(es));
4786         if (err) {
4787                 ext4_msg(sb, KERN_ERR, "filesystem"
4788                          " too large to mount safely on this system");
4789                 return err;
4790         }
4791
4792         /* check blocks count against device size */
4793         blocks_count = sb_bdev_nr_blocks(sb);
4794         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4795                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4796                        "exceeds size of device (%llu blocks)",
4797                        ext4_blocks_count(es), blocks_count);
4798                 return -EINVAL;
4799         }
4800
4801         /*
4802          * It makes no sense for the first data block to be beyond the end
4803          * of the filesystem.
4804          */
4805         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4806                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4807                          "block %u is beyond end of filesystem (%llu)",
4808                          le32_to_cpu(es->s_first_data_block),
4809                          ext4_blocks_count(es));
4810                 return -EINVAL;
4811         }
4812         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4813             (sbi->s_cluster_ratio == 1)) {
4814                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4815                          "block is 0 with a 1k block and cluster size");
4816                 return -EINVAL;
4817         }
4818
4819         blocks_count = (ext4_blocks_count(es) -
4820                         le32_to_cpu(es->s_first_data_block) +
4821                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4822         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4823         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4824                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4825                        "(block count %llu, first data block %u, "
4826                        "blocks per group %lu)", blocks_count,
4827                        ext4_blocks_count(es),
4828                        le32_to_cpu(es->s_first_data_block),
4829                        EXT4_BLOCKS_PER_GROUP(sb));
4830                 return -EINVAL;
4831         }
4832         sbi->s_groups_count = blocks_count;
4833         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4834                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4835         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4836             le32_to_cpu(es->s_inodes_count)) {
4837                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4838                          le32_to_cpu(es->s_inodes_count),
4839                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4840                 return -EINVAL;
4841         }
4842
4843         return 0;
4844 }
4845
4846 static int ext4_group_desc_init(struct super_block *sb,
4847                                 struct ext4_super_block *es,
4848                                 ext4_fsblk_t logical_sb_block,
4849                                 ext4_group_t *first_not_zeroed)
4850 {
4851         struct ext4_sb_info *sbi = EXT4_SB(sb);
4852         unsigned int db_count;
4853         ext4_fsblk_t block;
4854         int i;
4855
4856         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4857                    EXT4_DESC_PER_BLOCK(sb);
4858         if (ext4_has_feature_meta_bg(sb)) {
4859                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4860                         ext4_msg(sb, KERN_WARNING,
4861                                  "first meta block group too large: %u "
4862                                  "(group descriptor block count %u)",
4863                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4864                         return -EINVAL;
4865                 }
4866         }
4867         rcu_assign_pointer(sbi->s_group_desc,
4868                            kvmalloc_array(db_count,
4869                                           sizeof(struct buffer_head *),
4870                                           GFP_KERNEL));
4871         if (sbi->s_group_desc == NULL) {
4872                 ext4_msg(sb, KERN_ERR, "not enough memory");
4873                 return -ENOMEM;
4874         }
4875
4876         bgl_lock_init(sbi->s_blockgroup_lock);
4877
4878         /* Pre-read the descriptors into the buffer cache */
4879         for (i = 0; i < db_count; i++) {
4880                 block = descriptor_loc(sb, logical_sb_block, i);
4881                 ext4_sb_breadahead_unmovable(sb, block);
4882         }
4883
4884         for (i = 0; i < db_count; i++) {
4885                 struct buffer_head *bh;
4886
4887                 block = descriptor_loc(sb, logical_sb_block, i);
4888                 bh = ext4_sb_bread_unmovable(sb, block);
4889                 if (IS_ERR(bh)) {
4890                         ext4_msg(sb, KERN_ERR,
4891                                "can't read group descriptor %d", i);
4892                         sbi->s_gdb_count = i;
4893                         return PTR_ERR(bh);
4894                 }
4895                 rcu_read_lock();
4896                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4897                 rcu_read_unlock();
4898         }
4899         sbi->s_gdb_count = db_count;
4900         if (!ext4_check_descriptors(sb, logical_sb_block, first_not_zeroed)) {
4901                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4902                 return -EFSCORRUPTED;
4903         }
4904
4905         return 0;
4906 }
4907
4908 static int ext4_load_and_init_journal(struct super_block *sb,
4909                                       struct ext4_super_block *es,
4910                                       struct ext4_fs_context *ctx)
4911 {
4912         struct ext4_sb_info *sbi = EXT4_SB(sb);
4913         int err;
4914
4915         err = ext4_load_journal(sb, es, ctx->journal_devnum);
4916         if (err)
4917                 return err;
4918
4919         if (ext4_has_feature_64bit(sb) &&
4920             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4921                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4922                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4923                 goto out;
4924         }
4925
4926         if (!set_journal_csum_feature_set(sb)) {
4927                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4928                          "feature set");
4929                 goto out;
4930         }
4931
4932         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4933                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4934                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4935                 ext4_msg(sb, KERN_ERR,
4936                         "Failed to set fast commit journal feature");
4937                 goto out;
4938         }
4939
4940         /* We have now updated the journal if required, so we can
4941          * validate the data journaling mode. */
4942         switch (test_opt(sb, DATA_FLAGS)) {
4943         case 0:
4944                 /* No mode set, assume a default based on the journal
4945                  * capabilities: ORDERED_DATA if the journal can
4946                  * cope, else JOURNAL_DATA
4947                  */
4948                 if (jbd2_journal_check_available_features
4949                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4950                         set_opt(sb, ORDERED_DATA);
4951                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4952                 } else {
4953                         set_opt(sb, JOURNAL_DATA);
4954                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4955                 }
4956                 break;
4957
4958         case EXT4_MOUNT_ORDERED_DATA:
4959         case EXT4_MOUNT_WRITEBACK_DATA:
4960                 if (!jbd2_journal_check_available_features
4961                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4962                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4963                                "requested data journaling mode");
4964                         goto out;
4965                 }
4966                 break;
4967         default:
4968                 break;
4969         }
4970
4971         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4972             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4973                 ext4_msg(sb, KERN_ERR, "can't mount with "
4974                         "journal_async_commit in data=ordered mode");
4975                 goto out;
4976         }
4977
4978         set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
4979
4980         sbi->s_journal->j_submit_inode_data_buffers =
4981                 ext4_journal_submit_inode_data_buffers;
4982         sbi->s_journal->j_finish_inode_data_buffers =
4983                 ext4_journal_finish_inode_data_buffers;
4984
4985         return 0;
4986
4987 out:
4988         /* flush s_sb_upd_work before destroying the journal. */
4989         flush_work(&sbi->s_sb_upd_work);
4990         jbd2_journal_destroy(sbi->s_journal);
4991         sbi->s_journal = NULL;
4992         return -EINVAL;
4993 }
4994
4995 static int ext4_check_journal_data_mode(struct super_block *sb)
4996 {
4997         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4998                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with "
4999                             "data=journal disables delayed allocation, "
5000                             "dioread_nolock, O_DIRECT and fast_commit support!\n");
5001                 /* can't mount with both data=journal and dioread_nolock. */
5002                 clear_opt(sb, DIOREAD_NOLOCK);
5003                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
5004                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5005                         ext4_msg(sb, KERN_ERR, "can't mount with "
5006                                  "both data=journal and delalloc");
5007                         return -EINVAL;
5008                 }
5009                 if (test_opt(sb, DAX_ALWAYS)) {
5010                         ext4_msg(sb, KERN_ERR, "can't mount with "
5011                                  "both data=journal and dax");
5012                         return -EINVAL;
5013                 }
5014                 if (ext4_has_feature_encrypt(sb)) {
5015                         ext4_msg(sb, KERN_WARNING,
5016                                  "encrypted files will use data=ordered "
5017                                  "instead of data journaling mode");
5018                 }
5019                 if (test_opt(sb, DELALLOC))
5020                         clear_opt(sb, DELALLOC);
5021         } else {
5022                 sb->s_iflags |= SB_I_CGROUPWB;
5023         }
5024
5025         return 0;
5026 }
5027
5028 static int ext4_load_super(struct super_block *sb, ext4_fsblk_t *lsb,
5029                            int silent)
5030 {
5031         struct ext4_sb_info *sbi = EXT4_SB(sb);
5032         struct ext4_super_block *es;
5033         ext4_fsblk_t logical_sb_block;
5034         unsigned long offset = 0;
5035         struct buffer_head *bh;
5036         int ret = -EINVAL;
5037         int blocksize;
5038
5039         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
5040         if (!blocksize) {
5041                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
5042                 return -EINVAL;
5043         }
5044
5045         /*
5046          * The ext4 superblock will not be buffer aligned for other than 1kB
5047          * block sizes.  We need to calculate the offset from buffer start.
5048          */
5049         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
5050                 logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5051                 offset = do_div(logical_sb_block, blocksize);
5052         } else {
5053                 logical_sb_block = sbi->s_sb_block;
5054         }
5055
5056         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5057         if (IS_ERR(bh)) {
5058                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
5059                 return PTR_ERR(bh);
5060         }
5061         /*
5062          * Note: s_es must be initialized as soon as possible because
5063          *       some ext4 macro-instructions depend on its value
5064          */
5065         es = (struct ext4_super_block *) (bh->b_data + offset);
5066         sbi->s_es = es;
5067         sb->s_magic = le16_to_cpu(es->s_magic);
5068         if (sb->s_magic != EXT4_SUPER_MAGIC) {
5069                 if (!silent)
5070                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5071                 goto out;
5072         }
5073
5074         if (le32_to_cpu(es->s_log_block_size) >
5075             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5076                 ext4_msg(sb, KERN_ERR,
5077                          "Invalid log block size: %u",
5078                          le32_to_cpu(es->s_log_block_size));
5079                 goto out;
5080         }
5081         if (le32_to_cpu(es->s_log_cluster_size) >
5082             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5083                 ext4_msg(sb, KERN_ERR,
5084                          "Invalid log cluster size: %u",
5085                          le32_to_cpu(es->s_log_cluster_size));
5086                 goto out;
5087         }
5088
5089         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
5090
5091         /*
5092          * If the default block size is not the same as the real block size,
5093          * we need to reload it.
5094          */
5095         if (sb->s_blocksize == blocksize) {
5096                 *lsb = logical_sb_block;
5097                 sbi->s_sbh = bh;
5098                 return 0;
5099         }
5100
5101         /*
5102          * bh must be released before kill_bdev(), otherwise
5103          * it won't be freed and its page also. kill_bdev()
5104          * is called by sb_set_blocksize().
5105          */
5106         brelse(bh);
5107         /* Validate the filesystem blocksize */
5108         if (!sb_set_blocksize(sb, blocksize)) {
5109                 ext4_msg(sb, KERN_ERR, "bad block size %d",
5110                                 blocksize);
5111                 bh = NULL;
5112                 goto out;
5113         }
5114
5115         logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5116         offset = do_div(logical_sb_block, blocksize);
5117         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5118         if (IS_ERR(bh)) {
5119                 ext4_msg(sb, KERN_ERR, "Can't read superblock on 2nd try");
5120                 ret = PTR_ERR(bh);
5121                 bh = NULL;
5122                 goto out;
5123         }
5124         es = (struct ext4_super_block *)(bh->b_data + offset);
5125         sbi->s_es = es;
5126         if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
5127                 ext4_msg(sb, KERN_ERR, "Magic mismatch, very weird!");
5128                 goto out;
5129         }
5130         *lsb = logical_sb_block;
5131         sbi->s_sbh = bh;
5132         return 0;
5133 out:
5134         brelse(bh);
5135         return ret;
5136 }
5137
5138 static void ext4_hash_info_init(struct super_block *sb)
5139 {
5140         struct ext4_sb_info *sbi = EXT4_SB(sb);
5141         struct ext4_super_block *es = sbi->s_es;
5142         unsigned int i;
5143
5144         for (i = 0; i < 4; i++)
5145                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
5146
5147         sbi->s_def_hash_version = es->s_def_hash_version;
5148         if (ext4_has_feature_dir_index(sb)) {
5149                 i = le32_to_cpu(es->s_flags);
5150                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
5151                         sbi->s_hash_unsigned = 3;
5152                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
5153 #ifdef __CHAR_UNSIGNED__
5154                         if (!sb_rdonly(sb))
5155                                 es->s_flags |=
5156                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
5157                         sbi->s_hash_unsigned = 3;
5158 #else
5159                         if (!sb_rdonly(sb))
5160                                 es->s_flags |=
5161                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
5162 #endif
5163                 }
5164         }
5165 }
5166
5167 static int ext4_block_group_meta_init(struct super_block *sb, int silent)
5168 {
5169         struct ext4_sb_info *sbi = EXT4_SB(sb);
5170         struct ext4_super_block *es = sbi->s_es;
5171         int has_huge_files;
5172
5173         has_huge_files = ext4_has_feature_huge_file(sb);
5174         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
5175                                                       has_huge_files);
5176         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
5177
5178         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
5179         if (ext4_has_feature_64bit(sb)) {
5180                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
5181                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
5182                     !is_power_of_2(sbi->s_desc_size)) {
5183                         ext4_msg(sb, KERN_ERR,
5184                                "unsupported descriptor size %lu",
5185                                sbi->s_desc_size);
5186                         return -EINVAL;
5187                 }
5188         } else
5189                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
5190
5191         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
5192         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
5193
5194         sbi->s_inodes_per_block = sb->s_blocksize / EXT4_INODE_SIZE(sb);
5195         if (sbi->s_inodes_per_block == 0 || sbi->s_blocks_per_group == 0) {
5196                 if (!silent)
5197                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5198                 return -EINVAL;
5199         }
5200         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
5201             sbi->s_inodes_per_group > sb->s_blocksize * 8) {
5202                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
5203                          sbi->s_inodes_per_group);
5204                 return -EINVAL;
5205         }
5206         sbi->s_itb_per_group = sbi->s_inodes_per_group /
5207                                         sbi->s_inodes_per_block;
5208         sbi->s_desc_per_block = sb->s_blocksize / EXT4_DESC_SIZE(sb);
5209         sbi->s_mount_state = le16_to_cpu(es->s_state) & ~EXT4_FC_REPLAY;
5210         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
5211         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
5212
5213         return 0;
5214 }
5215
5216 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
5217 {
5218         struct ext4_super_block *es = NULL;
5219         struct ext4_sb_info *sbi = EXT4_SB(sb);
5220         ext4_fsblk_t logical_sb_block;
5221         struct inode *root;
5222         int needs_recovery;
5223         int err;
5224         ext4_group_t first_not_zeroed;
5225         struct ext4_fs_context *ctx = fc->fs_private;
5226         int silent = fc->sb_flags & SB_SILENT;
5227
5228         /* Set defaults for the variables that will be set during parsing */
5229         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO))
5230                 ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5231
5232         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
5233         sbi->s_sectors_written_start =
5234                 part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
5235
5236         err = ext4_load_super(sb, &logical_sb_block, silent);
5237         if (err)
5238                 goto out_fail;
5239
5240         es = sbi->s_es;
5241         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
5242
5243         err = ext4_init_metadata_csum(sb, es);
5244         if (err)
5245                 goto failed_mount;
5246
5247         ext4_set_def_opts(sb, es);
5248
5249         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
5250         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
5251         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
5252         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
5253         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
5254
5255         /*
5256          * set default s_li_wait_mult for lazyinit, for the case there is
5257          * no mount option specified.
5258          */
5259         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
5260
5261         err = ext4_inode_info_init(sb, es);
5262         if (err)
5263                 goto failed_mount;
5264
5265         err = parse_apply_sb_mount_options(sb, ctx);
5266         if (err < 0)
5267                 goto failed_mount;
5268
5269         sbi->s_def_mount_opt = sbi->s_mount_opt;
5270         sbi->s_def_mount_opt2 = sbi->s_mount_opt2;
5271
5272         err = ext4_check_opt_consistency(fc, sb);
5273         if (err < 0)
5274                 goto failed_mount;
5275
5276         ext4_apply_options(fc, sb);
5277
5278         err = ext4_encoding_init(sb, es);
5279         if (err)
5280                 goto failed_mount;
5281
5282         err = ext4_check_journal_data_mode(sb);
5283         if (err)
5284                 goto failed_mount;
5285
5286         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5287                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5288
5289         /* i_version is always enabled now */
5290         sb->s_flags |= SB_I_VERSION;
5291
5292         err = ext4_check_feature_compatibility(sb, es, silent);
5293         if (err)
5294                 goto failed_mount;
5295
5296         err = ext4_block_group_meta_init(sb, silent);
5297         if (err)
5298                 goto failed_mount;
5299
5300         ext4_hash_info_init(sb);
5301
5302         err = ext4_handle_clustersize(sb);
5303         if (err)
5304                 goto failed_mount;
5305
5306         err = ext4_check_geometry(sb, es);
5307         if (err)
5308                 goto failed_mount;
5309
5310         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5311         spin_lock_init(&sbi->s_error_lock);
5312         INIT_WORK(&sbi->s_sb_upd_work, update_super_work);
5313
5314         err = ext4_group_desc_init(sb, es, logical_sb_block, &first_not_zeroed);
5315         if (err)
5316                 goto failed_mount3;
5317
5318         err = ext4_es_register_shrinker(sbi);
5319         if (err)
5320                 goto failed_mount3;
5321
5322         sbi->s_stripe = ext4_get_stripe_size(sbi);
5323         /*
5324          * It's hard to get stripe aligned blocks if stripe is not aligned with
5325          * cluster, just disable stripe and alert user to simpfy code and avoid
5326          * stripe aligned allocation which will rarely successes.
5327          */
5328         if (sbi->s_stripe > 0 && sbi->s_cluster_ratio > 1 &&
5329             sbi->s_stripe % sbi->s_cluster_ratio != 0) {
5330                 ext4_msg(sb, KERN_WARNING,
5331                          "stripe (%lu) is not aligned with cluster size (%u), "
5332                          "stripe is disabled",
5333                          sbi->s_stripe, sbi->s_cluster_ratio);
5334                 sbi->s_stripe = 0;
5335         }
5336         sbi->s_extent_max_zeroout_kb = 32;
5337
5338         /*
5339          * set up enough so that it can read an inode
5340          */
5341         sb->s_op = &ext4_sops;
5342         sb->s_export_op = &ext4_export_ops;
5343         sb->s_xattr = ext4_xattr_handlers;
5344 #ifdef CONFIG_FS_ENCRYPTION
5345         sb->s_cop = &ext4_cryptops;
5346 #endif
5347 #ifdef CONFIG_FS_VERITY
5348         sb->s_vop = &ext4_verityops;
5349 #endif
5350 #ifdef CONFIG_QUOTA
5351         sb->dq_op = &ext4_quota_operations;
5352         if (ext4_has_feature_quota(sb))
5353                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
5354         else
5355                 sb->s_qcop = &ext4_qctl_operations;
5356         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5357 #endif
5358         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
5359
5360         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5361         mutex_init(&sbi->s_orphan_lock);
5362
5363         ext4_fast_commit_init(sb);
5364
5365         sb->s_root = NULL;
5366
5367         needs_recovery = (es->s_last_orphan != 0 ||
5368                           ext4_has_feature_orphan_present(sb) ||
5369                           ext4_has_feature_journal_needs_recovery(sb));
5370
5371         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb)) {
5372                 err = ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block));
5373                 if (err)
5374                         goto failed_mount3a;
5375         }
5376
5377         err = -EINVAL;
5378         /*
5379          * The first inode we look at is the journal inode.  Don't try
5380          * root first: it may be modified in the journal!
5381          */
5382         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5383                 err = ext4_load_and_init_journal(sb, es, ctx);
5384                 if (err)
5385                         goto failed_mount3a;
5386         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5387                    ext4_has_feature_journal_needs_recovery(sb)) {
5388                 ext4_msg(sb, KERN_ERR, "required journal recovery "
5389                        "suppressed and not mounted read-only");
5390                 goto failed_mount3a;
5391         } else {
5392                 /* Nojournal mode, all journal mount options are illegal */
5393                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5394                         ext4_msg(sb, KERN_ERR, "can't mount with "
5395                                  "journal_async_commit, fs mounted w/o journal");
5396                         goto failed_mount3a;
5397                 }
5398
5399                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
5400                         ext4_msg(sb, KERN_ERR, "can't mount with "
5401                                  "journal_checksum, fs mounted w/o journal");
5402                         goto failed_mount3a;
5403                 }
5404                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
5405                         ext4_msg(sb, KERN_ERR, "can't mount with "
5406                                  "commit=%lu, fs mounted w/o journal",
5407                                  sbi->s_commit_interval / HZ);
5408                         goto failed_mount3a;
5409                 }
5410                 if (EXT4_MOUNT_DATA_FLAGS &
5411                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
5412                         ext4_msg(sb, KERN_ERR, "can't mount with "
5413                                  "data=, fs mounted w/o journal");
5414                         goto failed_mount3a;
5415                 }
5416                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5417                 clear_opt(sb, JOURNAL_CHECKSUM);
5418                 clear_opt(sb, DATA_FLAGS);
5419                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
5420                 sbi->s_journal = NULL;
5421                 needs_recovery = 0;
5422         }
5423
5424         if (!test_opt(sb, NO_MBCACHE)) {
5425                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
5426                 if (!sbi->s_ea_block_cache) {
5427                         ext4_msg(sb, KERN_ERR,
5428                                  "Failed to create ea_block_cache");
5429                         err = -EINVAL;
5430                         goto failed_mount_wq;
5431                 }
5432
5433                 if (ext4_has_feature_ea_inode(sb)) {
5434                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5435                         if (!sbi->s_ea_inode_cache) {
5436                                 ext4_msg(sb, KERN_ERR,
5437                                          "Failed to create ea_inode_cache");
5438                                 err = -EINVAL;
5439                                 goto failed_mount_wq;
5440                         }
5441                 }
5442         }
5443
5444         /*
5445          * Get the # of file system overhead blocks from the
5446          * superblock if present.
5447          */
5448         sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5449         /* ignore the precalculated value if it is ridiculous */
5450         if (sbi->s_overhead > ext4_blocks_count(es))
5451                 sbi->s_overhead = 0;
5452         /*
5453          * If the bigalloc feature is not enabled recalculating the
5454          * overhead doesn't take long, so we might as well just redo
5455          * it to make sure we are using the correct value.
5456          */
5457         if (!ext4_has_feature_bigalloc(sb))
5458                 sbi->s_overhead = 0;
5459         if (sbi->s_overhead == 0) {
5460                 err = ext4_calculate_overhead(sb);
5461                 if (err)
5462                         goto failed_mount_wq;
5463         }
5464
5465         /*
5466          * The maximum number of concurrent works can be high and
5467          * concurrency isn't really necessary.  Limit it to 1.
5468          */
5469         EXT4_SB(sb)->rsv_conversion_wq =
5470                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5471         if (!EXT4_SB(sb)->rsv_conversion_wq) {
5472                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5473                 err = -ENOMEM;
5474                 goto failed_mount4;
5475         }
5476
5477         /*
5478          * The jbd2_journal_load will have done any necessary log recovery,
5479          * so we can safely mount the rest of the filesystem now.
5480          */
5481
5482         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5483         if (IS_ERR(root)) {
5484                 ext4_msg(sb, KERN_ERR, "get root inode failed");
5485                 err = PTR_ERR(root);
5486                 root = NULL;
5487                 goto failed_mount4;
5488         }
5489         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5490                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5491                 iput(root);
5492                 err = -EFSCORRUPTED;
5493                 goto failed_mount4;
5494         }
5495
5496         sb->s_root = d_make_root(root);
5497         if (!sb->s_root) {
5498                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
5499                 err = -ENOMEM;
5500                 goto failed_mount4;
5501         }
5502
5503         err = ext4_setup_super(sb, es, sb_rdonly(sb));
5504         if (err == -EROFS) {
5505                 sb->s_flags |= SB_RDONLY;
5506         } else if (err)
5507                 goto failed_mount4a;
5508
5509         ext4_set_resv_clusters(sb);
5510
5511         if (test_opt(sb, BLOCK_VALIDITY)) {
5512                 err = ext4_setup_system_zone(sb);
5513                 if (err) {
5514                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
5515                                  "zone (%d)", err);
5516                         goto failed_mount4a;
5517                 }
5518         }
5519         ext4_fc_replay_cleanup(sb);
5520
5521         ext4_ext_init(sb);
5522
5523         /*
5524          * Enable optimize_scan if number of groups is > threshold. This can be
5525          * turned off by passing "mb_optimize_scan=0". This can also be
5526          * turned on forcefully by passing "mb_optimize_scan=1".
5527          */
5528         if (!(ctx->spec & EXT4_SPEC_mb_optimize_scan)) {
5529                 if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5530                         set_opt2(sb, MB_OPTIMIZE_SCAN);
5531                 else
5532                         clear_opt2(sb, MB_OPTIMIZE_SCAN);
5533         }
5534
5535         err = ext4_mb_init(sb);
5536         if (err) {
5537                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5538                          err);
5539                 goto failed_mount5;
5540         }
5541
5542         /*
5543          * We can only set up the journal commit callback once
5544          * mballoc is initialized
5545          */
5546         if (sbi->s_journal)
5547                 sbi->s_journal->j_commit_callback =
5548                         ext4_journal_commit_callback;
5549
5550         err = ext4_percpu_param_init(sbi);
5551         if (err)
5552                 goto failed_mount6;
5553
5554         if (ext4_has_feature_flex_bg(sb))
5555                 if (!ext4_fill_flex_info(sb)) {
5556                         ext4_msg(sb, KERN_ERR,
5557                                "unable to initialize "
5558                                "flex_bg meta info!");
5559                         err = -ENOMEM;
5560                         goto failed_mount6;
5561                 }
5562
5563         err = ext4_register_li_request(sb, first_not_zeroed);
5564         if (err)
5565                 goto failed_mount6;
5566
5567         err = ext4_register_sysfs(sb);
5568         if (err)
5569                 goto failed_mount7;
5570
5571         err = ext4_init_orphan_info(sb);
5572         if (err)
5573                 goto failed_mount8;
5574 #ifdef CONFIG_QUOTA
5575         /* Enable quota usage during mount. */
5576         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5577                 err = ext4_enable_quotas(sb);
5578                 if (err)
5579                         goto failed_mount9;
5580         }
5581 #endif  /* CONFIG_QUOTA */
5582
5583         /*
5584          * Save the original bdev mapping's wb_err value which could be
5585          * used to detect the metadata async write error.
5586          */
5587         spin_lock_init(&sbi->s_bdev_wb_lock);
5588         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5589                                  &sbi->s_bdev_wb_err);
5590         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5591         ext4_orphan_cleanup(sb, es);
5592         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5593         /*
5594          * Update the checksum after updating free space/inode counters and
5595          * ext4_orphan_cleanup. Otherwise the superblock can have an incorrect
5596          * checksum in the buffer cache until it is written out and
5597          * e2fsprogs programs trying to open a file system immediately
5598          * after it is mounted can fail.
5599          */
5600         ext4_superblock_csum_set(sb);
5601         if (needs_recovery) {
5602                 ext4_msg(sb, KERN_INFO, "recovery complete");
5603                 err = ext4_mark_recovery_complete(sb, es);
5604                 if (err)
5605                         goto failed_mount10;
5606         }
5607
5608         if (test_opt(sb, DISCARD) && !bdev_max_discard_sectors(sb->s_bdev))
5609                 ext4_msg(sb, KERN_WARNING,
5610                          "mounting with \"discard\" option, but the device does not support discard");
5611
5612         if (es->s_error_count)
5613                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5614
5615         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5616         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5617         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5618         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5619         atomic_set(&sbi->s_warning_count, 0);
5620         atomic_set(&sbi->s_msg_count, 0);
5621
5622         return 0;
5623
5624 failed_mount10:
5625         ext4_quotas_off(sb, EXT4_MAXQUOTAS);
5626 failed_mount9: __maybe_unused
5627         ext4_release_orphan_info(sb);
5628 failed_mount8:
5629         ext4_unregister_sysfs(sb);
5630         kobject_put(&sbi->s_kobj);
5631 failed_mount7:
5632         ext4_unregister_li_request(sb);
5633 failed_mount6:
5634         ext4_mb_release(sb);
5635         ext4_flex_groups_free(sbi);
5636         ext4_percpu_param_destroy(sbi);
5637 failed_mount5:
5638         ext4_ext_release(sb);
5639         ext4_release_system_zone(sb);
5640 failed_mount4a:
5641         dput(sb->s_root);
5642         sb->s_root = NULL;
5643 failed_mount4:
5644         ext4_msg(sb, KERN_ERR, "mount failed");
5645         if (EXT4_SB(sb)->rsv_conversion_wq)
5646                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5647 failed_mount_wq:
5648         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5649         sbi->s_ea_inode_cache = NULL;
5650
5651         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5652         sbi->s_ea_block_cache = NULL;
5653
5654         if (sbi->s_journal) {
5655                 /* flush s_sb_upd_work before journal destroy. */
5656                 flush_work(&sbi->s_sb_upd_work);
5657                 jbd2_journal_destroy(sbi->s_journal);
5658                 sbi->s_journal = NULL;
5659         }
5660 failed_mount3a:
5661         ext4_es_unregister_shrinker(sbi);
5662 failed_mount3:
5663         /* flush s_sb_upd_work before sbi destroy */
5664         flush_work(&sbi->s_sb_upd_work);
5665         del_timer_sync(&sbi->s_err_report);
5666         ext4_stop_mmpd(sbi);
5667         ext4_group_desc_free(sbi);
5668 failed_mount:
5669         if (sbi->s_chksum_driver)
5670                 crypto_free_shash(sbi->s_chksum_driver);
5671
5672 #if IS_ENABLED(CONFIG_UNICODE)
5673         utf8_unload(sb->s_encoding);
5674 #endif
5675
5676 #ifdef CONFIG_QUOTA
5677         for (unsigned int i = 0; i < EXT4_MAXQUOTAS; i++)
5678                 kfree(get_qf_name(sb, sbi, i));
5679 #endif
5680         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5681         brelse(sbi->s_sbh);
5682         if (sbi->s_journal_bdev_handle) {
5683                 invalidate_bdev(sbi->s_journal_bdev_handle->bdev);
5684                 bdev_release(sbi->s_journal_bdev_handle);
5685         }
5686 out_fail:
5687         invalidate_bdev(sb->s_bdev);
5688         sb->s_fs_info = NULL;
5689         return err;
5690 }
5691
5692 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5693 {
5694         struct ext4_fs_context *ctx = fc->fs_private;
5695         struct ext4_sb_info *sbi;
5696         const char *descr;
5697         int ret;
5698
5699         sbi = ext4_alloc_sbi(sb);
5700         if (!sbi)
5701                 return -ENOMEM;
5702
5703         fc->s_fs_info = sbi;
5704
5705         /* Cleanup superblock name */
5706         strreplace(sb->s_id, '/', '!');
5707
5708         sbi->s_sb_block = 1;    /* Default super block location */
5709         if (ctx->spec & EXT4_SPEC_s_sb_block)
5710                 sbi->s_sb_block = ctx->s_sb_block;
5711
5712         ret = __ext4_fill_super(fc, sb);
5713         if (ret < 0)
5714                 goto free_sbi;
5715
5716         if (sbi->s_journal) {
5717                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5718                         descr = " journalled data mode";
5719                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5720                         descr = " ordered data mode";
5721                 else
5722                         descr = " writeback data mode";
5723         } else
5724                 descr = "out journal";
5725
5726         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5727                 ext4_msg(sb, KERN_INFO, "mounted filesystem %pU %s with%s. "
5728                          "Quota mode: %s.", &sb->s_uuid,
5729                          sb_rdonly(sb) ? "ro" : "r/w", descr,
5730                          ext4_quota_mode(sb));
5731
5732         /* Update the s_overhead_clusters if necessary */
5733         ext4_update_overhead(sb, false);
5734         return 0;
5735
5736 free_sbi:
5737         ext4_free_sbi(sbi);
5738         fc->s_fs_info = NULL;
5739         return ret;
5740 }
5741
5742 static int ext4_get_tree(struct fs_context *fc)
5743 {
5744         return get_tree_bdev(fc, ext4_fill_super);
5745 }
5746
5747 /*
5748  * Setup any per-fs journal parameters now.  We'll do this both on
5749  * initial mount, once the journal has been initialised but before we've
5750  * done any recovery; and again on any subsequent remount.
5751  */
5752 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5753 {
5754         struct ext4_sb_info *sbi = EXT4_SB(sb);
5755
5756         journal->j_commit_interval = sbi->s_commit_interval;
5757         journal->j_min_batch_time = sbi->s_min_batch_time;
5758         journal->j_max_batch_time = sbi->s_max_batch_time;
5759         ext4_fc_init(sb, journal);
5760
5761         write_lock(&journal->j_state_lock);
5762         if (test_opt(sb, BARRIER))
5763                 journal->j_flags |= JBD2_BARRIER;
5764         else
5765                 journal->j_flags &= ~JBD2_BARRIER;
5766         if (test_opt(sb, DATA_ERR_ABORT))
5767                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5768         else
5769                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5770         /*
5771          * Always enable journal cycle record option, letting the journal
5772          * records log transactions continuously between each mount.
5773          */
5774         journal->j_flags |= JBD2_CYCLE_RECORD;
5775         write_unlock(&journal->j_state_lock);
5776 }
5777
5778 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5779                                              unsigned int journal_inum)
5780 {
5781         struct inode *journal_inode;
5782
5783         /*
5784          * Test for the existence of a valid inode on disk.  Bad things
5785          * happen if we iget() an unused inode, as the subsequent iput()
5786          * will try to delete it.
5787          */
5788         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5789         if (IS_ERR(journal_inode)) {
5790                 ext4_msg(sb, KERN_ERR, "no journal found");
5791                 return ERR_CAST(journal_inode);
5792         }
5793         if (!journal_inode->i_nlink) {
5794                 make_bad_inode(journal_inode);
5795                 iput(journal_inode);
5796                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5797                 return ERR_PTR(-EFSCORRUPTED);
5798         }
5799         if (!S_ISREG(journal_inode->i_mode) || IS_ENCRYPTED(journal_inode)) {
5800                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5801                 iput(journal_inode);
5802                 return ERR_PTR(-EFSCORRUPTED);
5803         }
5804
5805         ext4_debug("Journal inode found at %p: %lld bytes\n",
5806                   journal_inode, journal_inode->i_size);
5807         return journal_inode;
5808 }
5809
5810 static int ext4_journal_bmap(journal_t *journal, sector_t *block)
5811 {
5812         struct ext4_map_blocks map;
5813         int ret;
5814
5815         if (journal->j_inode == NULL)
5816                 return 0;
5817
5818         map.m_lblk = *block;
5819         map.m_len = 1;
5820         ret = ext4_map_blocks(NULL, journal->j_inode, &map, 0);
5821         if (ret <= 0) {
5822                 ext4_msg(journal->j_inode->i_sb, KERN_CRIT,
5823                          "journal bmap failed: block %llu ret %d\n",
5824                          *block, ret);
5825                 jbd2_journal_abort(journal, ret ? ret : -EIO);
5826                 return ret;
5827         }
5828         *block = map.m_pblk;
5829         return 0;
5830 }
5831
5832 static journal_t *ext4_open_inode_journal(struct super_block *sb,
5833                                           unsigned int journal_inum)
5834 {
5835         struct inode *journal_inode;
5836         journal_t *journal;
5837
5838         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5839         if (IS_ERR(journal_inode))
5840                 return ERR_CAST(journal_inode);
5841
5842         journal = jbd2_journal_init_inode(journal_inode);
5843         if (IS_ERR(journal)) {
5844                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5845                 iput(journal_inode);
5846                 return ERR_CAST(journal);
5847         }
5848         journal->j_private = sb;
5849         journal->j_bmap = ext4_journal_bmap;
5850         ext4_init_journal_params(sb, journal);
5851         return journal;
5852 }
5853
5854 static struct bdev_handle *ext4_get_journal_blkdev(struct super_block *sb,
5855                                         dev_t j_dev, ext4_fsblk_t *j_start,
5856                                         ext4_fsblk_t *j_len)
5857 {
5858         struct buffer_head *bh;
5859         struct block_device *bdev;
5860         struct bdev_handle *bdev_handle;
5861         int hblock, blocksize;
5862         ext4_fsblk_t sb_block;
5863         unsigned long offset;
5864         struct ext4_super_block *es;
5865         int errno;
5866
5867         /* see get_tree_bdev why this is needed and safe */
5868         up_write(&sb->s_umount);
5869         bdev_handle = bdev_open_by_dev(j_dev, BLK_OPEN_READ | BLK_OPEN_WRITE,
5870                                        sb, &fs_holder_ops);
5871         down_write(&sb->s_umount);
5872         if (IS_ERR(bdev_handle)) {
5873                 ext4_msg(sb, KERN_ERR,
5874                          "failed to open journal device unknown-block(%u,%u) %ld",
5875                          MAJOR(j_dev), MINOR(j_dev), PTR_ERR(bdev_handle));
5876                 return bdev_handle;
5877         }
5878
5879         bdev = bdev_handle->bdev;
5880         blocksize = sb->s_blocksize;
5881         hblock = bdev_logical_block_size(bdev);
5882         if (blocksize < hblock) {
5883                 ext4_msg(sb, KERN_ERR,
5884                         "blocksize too small for journal device");
5885                 errno = -EINVAL;
5886                 goto out_bdev;
5887         }
5888
5889         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5890         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5891         set_blocksize(bdev, blocksize);
5892         bh = __bread(bdev, sb_block, blocksize);
5893         if (!bh) {
5894                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5895                        "external journal");
5896                 errno = -EINVAL;
5897                 goto out_bdev;
5898         }
5899
5900         es = (struct ext4_super_block *) (bh->b_data + offset);
5901         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5902             !(le32_to_cpu(es->s_feature_incompat) &
5903               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5904                 ext4_msg(sb, KERN_ERR, "external journal has bad superblock");
5905                 errno = -EFSCORRUPTED;
5906                 goto out_bh;
5907         }
5908
5909         if ((le32_to_cpu(es->s_feature_ro_compat) &
5910              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5911             es->s_checksum != ext4_superblock_csum(sb, es)) {
5912                 ext4_msg(sb, KERN_ERR, "external journal has corrupt superblock");
5913                 errno = -EFSCORRUPTED;
5914                 goto out_bh;
5915         }
5916
5917         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5918                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5919                 errno = -EFSCORRUPTED;
5920                 goto out_bh;
5921         }
5922
5923         *j_start = sb_block + 1;
5924         *j_len = ext4_blocks_count(es);
5925         brelse(bh);
5926         return bdev_handle;
5927
5928 out_bh:
5929         brelse(bh);
5930 out_bdev:
5931         bdev_release(bdev_handle);
5932         return ERR_PTR(errno);
5933 }
5934
5935 static journal_t *ext4_open_dev_journal(struct super_block *sb,
5936                                         dev_t j_dev)
5937 {
5938         journal_t *journal;
5939         ext4_fsblk_t j_start;
5940         ext4_fsblk_t j_len;
5941         struct bdev_handle *bdev_handle;
5942         int errno = 0;
5943
5944         bdev_handle = ext4_get_journal_blkdev(sb, j_dev, &j_start, &j_len);
5945         if (IS_ERR(bdev_handle))
5946                 return ERR_CAST(bdev_handle);
5947
5948         journal = jbd2_journal_init_dev(bdev_handle->bdev, sb->s_bdev, j_start,
5949                                         j_len, sb->s_blocksize);
5950         if (IS_ERR(journal)) {
5951                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5952                 errno = PTR_ERR(journal);
5953                 goto out_bdev;
5954         }
5955         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5956                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5957                                         "user (unsupported) - %d",
5958                         be32_to_cpu(journal->j_superblock->s_nr_users));
5959                 errno = -EINVAL;
5960                 goto out_journal;
5961         }
5962         journal->j_private = sb;
5963         EXT4_SB(sb)->s_journal_bdev_handle = bdev_handle;
5964         ext4_init_journal_params(sb, journal);
5965         return journal;
5966
5967 out_journal:
5968         jbd2_journal_destroy(journal);
5969 out_bdev:
5970         bdev_release(bdev_handle);
5971         return ERR_PTR(errno);
5972 }
5973
5974 static int ext4_load_journal(struct super_block *sb,
5975                              struct ext4_super_block *es,
5976                              unsigned long journal_devnum)
5977 {
5978         journal_t *journal;
5979         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5980         dev_t journal_dev;
5981         int err = 0;
5982         int really_read_only;
5983         int journal_dev_ro;
5984
5985         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5986                 return -EFSCORRUPTED;
5987
5988         if (journal_devnum &&
5989             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5990                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5991                         "numbers have changed");
5992                 journal_dev = new_decode_dev(journal_devnum);
5993         } else
5994                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5995
5996         if (journal_inum && journal_dev) {
5997                 ext4_msg(sb, KERN_ERR,
5998                          "filesystem has both journal inode and journal device!");
5999                 return -EINVAL;
6000         }
6001
6002         if (journal_inum) {
6003                 journal = ext4_open_inode_journal(sb, journal_inum);
6004                 if (IS_ERR(journal))
6005                         return PTR_ERR(journal);
6006         } else {
6007                 journal = ext4_open_dev_journal(sb, journal_dev);
6008                 if (IS_ERR(journal))
6009                         return PTR_ERR(journal);
6010         }
6011
6012         journal_dev_ro = bdev_read_only(journal->j_dev);
6013         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
6014
6015         if (journal_dev_ro && !sb_rdonly(sb)) {
6016                 ext4_msg(sb, KERN_ERR,
6017                          "journal device read-only, try mounting with '-o ro'");
6018                 err = -EROFS;
6019                 goto err_out;
6020         }
6021
6022         /*
6023          * Are we loading a blank journal or performing recovery after a
6024          * crash?  For recovery, we need to check in advance whether we
6025          * can get read-write access to the device.
6026          */
6027         if (ext4_has_feature_journal_needs_recovery(sb)) {
6028                 if (sb_rdonly(sb)) {
6029                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
6030                                         "required on readonly filesystem");
6031                         if (really_read_only) {
6032                                 ext4_msg(sb, KERN_ERR, "write access "
6033                                         "unavailable, cannot proceed "
6034                                         "(try mounting with noload)");
6035                                 err = -EROFS;
6036                                 goto err_out;
6037                         }
6038                         ext4_msg(sb, KERN_INFO, "write access will "
6039                                "be enabled during recovery");
6040                 }
6041         }
6042
6043         if (!(journal->j_flags & JBD2_BARRIER))
6044                 ext4_msg(sb, KERN_INFO, "barriers disabled");
6045
6046         if (!ext4_has_feature_journal_needs_recovery(sb))
6047                 err = jbd2_journal_wipe(journal, !really_read_only);
6048         if (!err) {
6049                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
6050                 __le16 orig_state;
6051                 bool changed = false;
6052
6053                 if (save)
6054                         memcpy(save, ((char *) es) +
6055                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
6056                 err = jbd2_journal_load(journal);
6057                 if (save && memcmp(((char *) es) + EXT4_S_ERR_START,
6058                                    save, EXT4_S_ERR_LEN)) {
6059                         memcpy(((char *) es) + EXT4_S_ERR_START,
6060                                save, EXT4_S_ERR_LEN);
6061                         changed = true;
6062                 }
6063                 kfree(save);
6064                 orig_state = es->s_state;
6065                 es->s_state |= cpu_to_le16(EXT4_SB(sb)->s_mount_state &
6066                                            EXT4_ERROR_FS);
6067                 if (orig_state != es->s_state)
6068                         changed = true;
6069                 /* Write out restored error information to the superblock */
6070                 if (changed && !really_read_only) {
6071                         int err2;
6072                         err2 = ext4_commit_super(sb);
6073                         err = err ? : err2;
6074                 }
6075         }
6076
6077         if (err) {
6078                 ext4_msg(sb, KERN_ERR, "error loading journal");
6079                 goto err_out;
6080         }
6081
6082         EXT4_SB(sb)->s_journal = journal;
6083         err = ext4_clear_journal_err(sb, es);
6084         if (err) {
6085                 EXT4_SB(sb)->s_journal = NULL;
6086                 jbd2_journal_destroy(journal);
6087                 return err;
6088         }
6089
6090         if (!really_read_only && journal_devnum &&
6091             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
6092                 es->s_journal_dev = cpu_to_le32(journal_devnum);
6093                 ext4_commit_super(sb);
6094         }
6095         if (!really_read_only && journal_inum &&
6096             journal_inum != le32_to_cpu(es->s_journal_inum)) {
6097                 es->s_journal_inum = cpu_to_le32(journal_inum);
6098                 ext4_commit_super(sb);
6099         }
6100
6101         return 0;
6102
6103 err_out:
6104         jbd2_journal_destroy(journal);
6105         return err;
6106 }
6107
6108 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
6109 static void ext4_update_super(struct super_block *sb)
6110 {
6111         struct ext4_sb_info *sbi = EXT4_SB(sb);
6112         struct ext4_super_block *es = sbi->s_es;
6113         struct buffer_head *sbh = sbi->s_sbh;
6114
6115         lock_buffer(sbh);
6116         /*
6117          * If the file system is mounted read-only, don't update the
6118          * superblock write time.  This avoids updating the superblock
6119          * write time when we are mounting the root file system
6120          * read/only but we need to replay the journal; at that point,
6121          * for people who are east of GMT and who make their clock
6122          * tick in localtime for Windows bug-for-bug compatibility,
6123          * the clock is set in the future, and this will cause e2fsck
6124          * to complain and force a full file system check.
6125          */
6126         if (!sb_rdonly(sb))
6127                 ext4_update_tstamp(es, s_wtime);
6128         es->s_kbytes_written =
6129                 cpu_to_le64(sbi->s_kbytes_written +
6130                     ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
6131                       sbi->s_sectors_written_start) >> 1));
6132         if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
6133                 ext4_free_blocks_count_set(es,
6134                         EXT4_C2B(sbi, percpu_counter_sum_positive(
6135                                 &sbi->s_freeclusters_counter)));
6136         if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
6137                 es->s_free_inodes_count =
6138                         cpu_to_le32(percpu_counter_sum_positive(
6139                                 &sbi->s_freeinodes_counter));
6140         /* Copy error information to the on-disk superblock */
6141         spin_lock(&sbi->s_error_lock);
6142         if (sbi->s_add_error_count > 0) {
6143                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6144                 if (!es->s_first_error_time && !es->s_first_error_time_hi) {
6145                         __ext4_update_tstamp(&es->s_first_error_time,
6146                                              &es->s_first_error_time_hi,
6147                                              sbi->s_first_error_time);
6148                         strncpy(es->s_first_error_func, sbi->s_first_error_func,
6149                                 sizeof(es->s_first_error_func));
6150                         es->s_first_error_line =
6151                                 cpu_to_le32(sbi->s_first_error_line);
6152                         es->s_first_error_ino =
6153                                 cpu_to_le32(sbi->s_first_error_ino);
6154                         es->s_first_error_block =
6155                                 cpu_to_le64(sbi->s_first_error_block);
6156                         es->s_first_error_errcode =
6157                                 ext4_errno_to_code(sbi->s_first_error_code);
6158                 }
6159                 __ext4_update_tstamp(&es->s_last_error_time,
6160                                      &es->s_last_error_time_hi,
6161                                      sbi->s_last_error_time);
6162                 strncpy(es->s_last_error_func, sbi->s_last_error_func,
6163                         sizeof(es->s_last_error_func));
6164                 es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
6165                 es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
6166                 es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
6167                 es->s_last_error_errcode =
6168                                 ext4_errno_to_code(sbi->s_last_error_code);
6169                 /*
6170                  * Start the daily error reporting function if it hasn't been
6171                  * started already
6172                  */
6173                 if (!es->s_error_count)
6174                         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
6175                 le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
6176                 sbi->s_add_error_count = 0;
6177         }
6178         spin_unlock(&sbi->s_error_lock);
6179
6180         ext4_superblock_csum_set(sb);
6181         unlock_buffer(sbh);
6182 }
6183
6184 static int ext4_commit_super(struct super_block *sb)
6185 {
6186         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
6187
6188         if (!sbh)
6189                 return -EINVAL;
6190         if (block_device_ejected(sb))
6191                 return -ENODEV;
6192
6193         ext4_update_super(sb);
6194
6195         lock_buffer(sbh);
6196         /* Buffer got discarded which means block device got invalidated */
6197         if (!buffer_mapped(sbh)) {
6198                 unlock_buffer(sbh);
6199                 return -EIO;
6200         }
6201
6202         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
6203                 /*
6204                  * Oh, dear.  A previous attempt to write the
6205                  * superblock failed.  This could happen because the
6206                  * USB device was yanked out.  Or it could happen to
6207                  * be a transient write error and maybe the block will
6208                  * be remapped.  Nothing we can do but to retry the
6209                  * write and hope for the best.
6210                  */
6211                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
6212                        "superblock detected");
6213                 clear_buffer_write_io_error(sbh);
6214                 set_buffer_uptodate(sbh);
6215         }
6216         get_bh(sbh);
6217         /* Clear potential dirty bit if it was journalled update */
6218         clear_buffer_dirty(sbh);
6219         sbh->b_end_io = end_buffer_write_sync;
6220         submit_bh(REQ_OP_WRITE | REQ_SYNC |
6221                   (test_opt(sb, BARRIER) ? REQ_FUA : 0), sbh);
6222         wait_on_buffer(sbh);
6223         if (buffer_write_io_error(sbh)) {
6224                 ext4_msg(sb, KERN_ERR, "I/O error while writing "
6225                        "superblock");
6226                 clear_buffer_write_io_error(sbh);
6227                 set_buffer_uptodate(sbh);
6228                 return -EIO;
6229         }
6230         return 0;
6231 }
6232
6233 /*
6234  * Have we just finished recovery?  If so, and if we are mounting (or
6235  * remounting) the filesystem readonly, then we will end up with a
6236  * consistent fs on disk.  Record that fact.
6237  */
6238 static int ext4_mark_recovery_complete(struct super_block *sb,
6239                                        struct ext4_super_block *es)
6240 {
6241         int err;
6242         journal_t *journal = EXT4_SB(sb)->s_journal;
6243
6244         if (!ext4_has_feature_journal(sb)) {
6245                 if (journal != NULL) {
6246                         ext4_error(sb, "Journal got removed while the fs was "
6247                                    "mounted!");
6248                         return -EFSCORRUPTED;
6249                 }
6250                 return 0;
6251         }
6252         jbd2_journal_lock_updates(journal);
6253         err = jbd2_journal_flush(journal, 0);
6254         if (err < 0)
6255                 goto out;
6256
6257         if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6258             ext4_has_feature_orphan_present(sb))) {
6259                 if (!ext4_orphan_file_empty(sb)) {
6260                         ext4_error(sb, "Orphan file not empty on read-only fs.");
6261                         err = -EFSCORRUPTED;
6262                         goto out;
6263                 }
6264                 ext4_clear_feature_journal_needs_recovery(sb);
6265                 ext4_clear_feature_orphan_present(sb);
6266                 ext4_commit_super(sb);
6267         }
6268 out:
6269         jbd2_journal_unlock_updates(journal);
6270         return err;
6271 }
6272
6273 /*
6274  * If we are mounting (or read-write remounting) a filesystem whose journal
6275  * has recorded an error from a previous lifetime, move that error to the
6276  * main filesystem now.
6277  */
6278 static int ext4_clear_journal_err(struct super_block *sb,
6279                                    struct ext4_super_block *es)
6280 {
6281         journal_t *journal;
6282         int j_errno;
6283         const char *errstr;
6284
6285         if (!ext4_has_feature_journal(sb)) {
6286                 ext4_error(sb, "Journal got removed while the fs was mounted!");
6287                 return -EFSCORRUPTED;
6288         }
6289
6290         journal = EXT4_SB(sb)->s_journal;
6291
6292         /*
6293          * Now check for any error status which may have been recorded in the
6294          * journal by a prior ext4_error() or ext4_abort()
6295          */
6296
6297         j_errno = jbd2_journal_errno(journal);
6298         if (j_errno) {
6299                 char nbuf[16];
6300
6301                 errstr = ext4_decode_error(sb, j_errno, nbuf);
6302                 ext4_warning(sb, "Filesystem error recorded "
6303                              "from previous mount: %s", errstr);
6304
6305                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6306                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6307                 j_errno = ext4_commit_super(sb);
6308                 if (j_errno)
6309                         return j_errno;
6310                 ext4_warning(sb, "Marked fs in need of filesystem check.");
6311
6312                 jbd2_journal_clear_err(journal);
6313                 jbd2_journal_update_sb_errno(journal);
6314         }
6315         return 0;
6316 }
6317
6318 /*
6319  * Force the running and committing transactions to commit,
6320  * and wait on the commit.
6321  */
6322 int ext4_force_commit(struct super_block *sb)
6323 {
6324         return ext4_journal_force_commit(EXT4_SB(sb)->s_journal);
6325 }
6326
6327 static int ext4_sync_fs(struct super_block *sb, int wait)
6328 {
6329         int ret = 0;
6330         tid_t target;
6331         bool needs_barrier = false;
6332         struct ext4_sb_info *sbi = EXT4_SB(sb);
6333
6334         if (unlikely(ext4_forced_shutdown(sb)))
6335                 return 0;
6336
6337         trace_ext4_sync_fs(sb, wait);
6338         flush_workqueue(sbi->rsv_conversion_wq);
6339         /*
6340          * Writeback quota in non-journalled quota case - journalled quota has
6341          * no dirty dquots
6342          */
6343         dquot_writeback_dquots(sb, -1);
6344         /*
6345          * Data writeback is possible w/o journal transaction, so barrier must
6346          * being sent at the end of the function. But we can skip it if
6347          * transaction_commit will do it for us.
6348          */
6349         if (sbi->s_journal) {
6350                 target = jbd2_get_latest_transaction(sbi->s_journal);
6351                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6352                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6353                         needs_barrier = true;
6354
6355                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6356                         if (wait)
6357                                 ret = jbd2_log_wait_commit(sbi->s_journal,
6358                                                            target);
6359                 }
6360         } else if (wait && test_opt(sb, BARRIER))
6361                 needs_barrier = true;
6362         if (needs_barrier) {
6363                 int err;
6364                 err = blkdev_issue_flush(sb->s_bdev);
6365                 if (!ret)
6366                         ret = err;
6367         }
6368
6369         return ret;
6370 }
6371
6372 /*
6373  * LVM calls this function before a (read-only) snapshot is created.  This
6374  * gives us a chance to flush the journal completely and mark the fs clean.
6375  *
6376  * Note that only this function cannot bring a filesystem to be in a clean
6377  * state independently. It relies on upper layer to stop all data & metadata
6378  * modifications.
6379  */
6380 static int ext4_freeze(struct super_block *sb)
6381 {
6382         int error = 0;
6383         journal_t *journal = EXT4_SB(sb)->s_journal;
6384
6385         if (journal) {
6386                 /* Now we set up the journal barrier. */
6387                 jbd2_journal_lock_updates(journal);
6388
6389                 /*
6390                  * Don't clear the needs_recovery flag if we failed to
6391                  * flush the journal.
6392                  */
6393                 error = jbd2_journal_flush(journal, 0);
6394                 if (error < 0)
6395                         goto out;
6396
6397                 /* Journal blocked and flushed, clear needs_recovery flag. */
6398                 ext4_clear_feature_journal_needs_recovery(sb);
6399                 if (ext4_orphan_file_empty(sb))
6400                         ext4_clear_feature_orphan_present(sb);
6401         }
6402
6403         error = ext4_commit_super(sb);
6404 out:
6405         if (journal)
6406                 /* we rely on upper layer to stop further updates */
6407                 jbd2_journal_unlock_updates(journal);
6408         return error;
6409 }
6410
6411 /*
6412  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6413  * flag here, even though the filesystem is not technically dirty yet.
6414  */
6415 static int ext4_unfreeze(struct super_block *sb)
6416 {
6417         if (ext4_forced_shutdown(sb))
6418                 return 0;
6419
6420         if (EXT4_SB(sb)->s_journal) {
6421                 /* Reset the needs_recovery flag before the fs is unlocked. */
6422                 ext4_set_feature_journal_needs_recovery(sb);
6423                 if (ext4_has_feature_orphan_file(sb))
6424                         ext4_set_feature_orphan_present(sb);
6425         }
6426
6427         ext4_commit_super(sb);
6428         return 0;
6429 }
6430
6431 /*
6432  * Structure to save mount options for ext4_remount's benefit
6433  */
6434 struct ext4_mount_options {
6435         unsigned long s_mount_opt;
6436         unsigned long s_mount_opt2;
6437         kuid_t s_resuid;
6438         kgid_t s_resgid;
6439         unsigned long s_commit_interval;
6440         u32 s_min_batch_time, s_max_batch_time;
6441 #ifdef CONFIG_QUOTA
6442         int s_jquota_fmt;
6443         char *s_qf_names[EXT4_MAXQUOTAS];
6444 #endif
6445 };
6446
6447 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6448 {
6449         struct ext4_fs_context *ctx = fc->fs_private;
6450         struct ext4_super_block *es;
6451         struct ext4_sb_info *sbi = EXT4_SB(sb);
6452         unsigned long old_sb_flags;
6453         struct ext4_mount_options old_opts;
6454         ext4_group_t g;
6455         int err = 0;
6456         int alloc_ctx;
6457 #ifdef CONFIG_QUOTA
6458         int enable_quota = 0;
6459         int i, j;
6460         char *to_free[EXT4_MAXQUOTAS];
6461 #endif
6462
6463
6464         /* Store the original options */
6465         old_sb_flags = sb->s_flags;
6466         old_opts.s_mount_opt = sbi->s_mount_opt;
6467         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6468         old_opts.s_resuid = sbi->s_resuid;
6469         old_opts.s_resgid = sbi->s_resgid;
6470         old_opts.s_commit_interval = sbi->s_commit_interval;
6471         old_opts.s_min_batch_time = sbi->s_min_batch_time;
6472         old_opts.s_max_batch_time = sbi->s_max_batch_time;
6473 #ifdef CONFIG_QUOTA
6474         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6475         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6476                 if (sbi->s_qf_names[i]) {
6477                         char *qf_name = get_qf_name(sb, sbi, i);
6478
6479                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6480                         if (!old_opts.s_qf_names[i]) {
6481                                 for (j = 0; j < i; j++)
6482                                         kfree(old_opts.s_qf_names[j]);
6483                                 return -ENOMEM;
6484                         }
6485                 } else
6486                         old_opts.s_qf_names[i] = NULL;
6487 #endif
6488         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)) {
6489                 if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6490                         ctx->journal_ioprio =
6491                                 sbi->s_journal->j_task->io_context->ioprio;
6492                 else
6493                         ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
6494
6495         }
6496
6497         /*
6498          * Changing the DIOREAD_NOLOCK or DELALLOC mount options may cause
6499          * two calls to ext4_should_dioread_nolock() to return inconsistent
6500          * values, triggering WARN_ON in ext4_add_complete_io(). we grab
6501          * here s_writepages_rwsem to avoid race between writepages ops and
6502          * remount.
6503          */
6504         alloc_ctx = ext4_writepages_down_write(sb);
6505         ext4_apply_options(fc, sb);
6506         ext4_writepages_up_write(sb, alloc_ctx);
6507
6508         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6509             test_opt(sb, JOURNAL_CHECKSUM)) {
6510                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6511                          "during remount not supported; ignoring");
6512                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6513         }
6514
6515         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6516                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6517                         ext4_msg(sb, KERN_ERR, "can't mount with "
6518                                  "both data=journal and delalloc");
6519                         err = -EINVAL;
6520                         goto restore_opts;
6521                 }
6522                 if (test_opt(sb, DIOREAD_NOLOCK)) {
6523                         ext4_msg(sb, KERN_ERR, "can't mount with "
6524                                  "both data=journal and dioread_nolock");
6525                         err = -EINVAL;
6526                         goto restore_opts;
6527                 }
6528         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6529                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6530                         ext4_msg(sb, KERN_ERR, "can't mount with "
6531                                 "journal_async_commit in data=ordered mode");
6532                         err = -EINVAL;
6533                         goto restore_opts;
6534                 }
6535         }
6536
6537         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6538                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6539                 err = -EINVAL;
6540                 goto restore_opts;
6541         }
6542
6543         if (test_opt2(sb, ABORT))
6544                 ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6545
6546         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6547                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6548
6549         es = sbi->s_es;
6550
6551         if (sbi->s_journal) {
6552                 ext4_init_journal_params(sb, sbi->s_journal);
6553                 set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6554         }
6555
6556         /* Flush outstanding errors before changing fs state */
6557         flush_work(&sbi->s_sb_upd_work);
6558
6559         if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6560                 if (ext4_forced_shutdown(sb)) {
6561                         err = -EROFS;
6562                         goto restore_opts;
6563                 }
6564
6565                 if (fc->sb_flags & SB_RDONLY) {
6566                         err = sync_filesystem(sb);
6567                         if (err < 0)
6568                                 goto restore_opts;
6569                         err = dquot_suspend(sb, -1);
6570                         if (err < 0)
6571                                 goto restore_opts;
6572
6573                         /*
6574                          * First of all, the unconditional stuff we have to do
6575                          * to disable replay of the journal when we next remount
6576                          */
6577                         sb->s_flags |= SB_RDONLY;
6578
6579                         /*
6580                          * OK, test if we are remounting a valid rw partition
6581                          * readonly, and if so set the rdonly flag and then
6582                          * mark the partition as valid again.
6583                          */
6584                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6585                             (sbi->s_mount_state & EXT4_VALID_FS))
6586                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
6587
6588                         if (sbi->s_journal) {
6589                                 /*
6590                                  * We let remount-ro finish even if marking fs
6591                                  * as clean failed...
6592                                  */
6593                                 ext4_mark_recovery_complete(sb, es);
6594                         }
6595                 } else {
6596                         /* Make sure we can mount this feature set readwrite */
6597                         if (ext4_has_feature_readonly(sb) ||
6598                             !ext4_feature_set_ok(sb, 0)) {
6599                                 err = -EROFS;
6600                                 goto restore_opts;
6601                         }
6602                         /*
6603                          * Make sure the group descriptor checksums
6604                          * are sane.  If they aren't, refuse to remount r/w.
6605                          */
6606                         for (g = 0; g < sbi->s_groups_count; g++) {
6607                                 struct ext4_group_desc *gdp =
6608                                         ext4_get_group_desc(sb, g, NULL);
6609
6610                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6611                                         ext4_msg(sb, KERN_ERR,
6612                "ext4_remount: Checksum for group %u failed (%u!=%u)",
6613                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6614                                                le16_to_cpu(gdp->bg_checksum));
6615                                         err = -EFSBADCRC;
6616                                         goto restore_opts;
6617                                 }
6618                         }
6619
6620                         /*
6621                          * If we have an unprocessed orphan list hanging
6622                          * around from a previously readonly bdev mount,
6623                          * require a full umount/remount for now.
6624                          */
6625                         if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6626                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
6627                                        "remount RDWR because of unprocessed "
6628                                        "orphan inode list.  Please "
6629                                        "umount/remount instead");
6630                                 err = -EINVAL;
6631                                 goto restore_opts;
6632                         }
6633
6634                         /*
6635                          * Mounting a RDONLY partition read-write, so reread
6636                          * and store the current valid flag.  (It may have
6637                          * been changed by e2fsck since we originally mounted
6638                          * the partition.)
6639                          */
6640                         if (sbi->s_journal) {
6641                                 err = ext4_clear_journal_err(sb, es);
6642                                 if (err)
6643                                         goto restore_opts;
6644                         }
6645                         sbi->s_mount_state = (le16_to_cpu(es->s_state) &
6646                                               ~EXT4_FC_REPLAY);
6647
6648                         err = ext4_setup_super(sb, es, 0);
6649                         if (err)
6650                                 goto restore_opts;
6651
6652                         sb->s_flags &= ~SB_RDONLY;
6653                         if (ext4_has_feature_mmp(sb)) {
6654                                 err = ext4_multi_mount_protect(sb,
6655                                                 le64_to_cpu(es->s_mmp_block));
6656                                 if (err)
6657                                         goto restore_opts;
6658                         }
6659 #ifdef CONFIG_QUOTA
6660                         enable_quota = 1;
6661 #endif
6662                 }
6663         }
6664
6665         /*
6666          * Handle creation of system zone data early because it can fail.
6667          * Releasing of existing data is done when we are sure remount will
6668          * succeed.
6669          */
6670         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6671                 err = ext4_setup_system_zone(sb);
6672                 if (err)
6673                         goto restore_opts;
6674         }
6675
6676         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6677                 err = ext4_commit_super(sb);
6678                 if (err)
6679                         goto restore_opts;
6680         }
6681
6682 #ifdef CONFIG_QUOTA
6683         if (enable_quota) {
6684                 if (sb_any_quota_suspended(sb))
6685                         dquot_resume(sb, -1);
6686                 else if (ext4_has_feature_quota(sb)) {
6687                         err = ext4_enable_quotas(sb);
6688                         if (err)
6689                                 goto restore_opts;
6690                 }
6691         }
6692         /* Release old quota file names */
6693         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6694                 kfree(old_opts.s_qf_names[i]);
6695 #endif
6696         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6697                 ext4_release_system_zone(sb);
6698
6699         /*
6700          * Reinitialize lazy itable initialization thread based on
6701          * current settings
6702          */
6703         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6704                 ext4_unregister_li_request(sb);
6705         else {
6706                 ext4_group_t first_not_zeroed;
6707                 first_not_zeroed = ext4_has_uninit_itable(sb);
6708                 ext4_register_li_request(sb, first_not_zeroed);
6709         }
6710
6711         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6712                 ext4_stop_mmpd(sbi);
6713
6714         return 0;
6715
6716 restore_opts:
6717         /*
6718          * If there was a failing r/w to ro transition, we may need to
6719          * re-enable quota
6720          */
6721         if (sb_rdonly(sb) && !(old_sb_flags & SB_RDONLY) &&
6722             sb_any_quota_suspended(sb))
6723                 dquot_resume(sb, -1);
6724
6725         alloc_ctx = ext4_writepages_down_write(sb);
6726         sb->s_flags = old_sb_flags;
6727         sbi->s_mount_opt = old_opts.s_mount_opt;
6728         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6729         sbi->s_resuid = old_opts.s_resuid;
6730         sbi->s_resgid = old_opts.s_resgid;
6731         sbi->s_commit_interval = old_opts.s_commit_interval;
6732         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6733         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6734         ext4_writepages_up_write(sb, alloc_ctx);
6735
6736         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6737                 ext4_release_system_zone(sb);
6738 #ifdef CONFIG_QUOTA
6739         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6740         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6741                 to_free[i] = get_qf_name(sb, sbi, i);
6742                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6743         }
6744         synchronize_rcu();
6745         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6746                 kfree(to_free[i]);
6747 #endif
6748         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6749                 ext4_stop_mmpd(sbi);
6750         return err;
6751 }
6752
6753 static int ext4_reconfigure(struct fs_context *fc)
6754 {
6755         struct super_block *sb = fc->root->d_sb;
6756         int ret;
6757
6758         fc->s_fs_info = EXT4_SB(sb);
6759
6760         ret = ext4_check_opt_consistency(fc, sb);
6761         if (ret < 0)
6762                 return ret;
6763
6764         ret = __ext4_remount(fc, sb);
6765         if (ret < 0)
6766                 return ret;
6767
6768         ext4_msg(sb, KERN_INFO, "re-mounted %pU %s. Quota mode: %s.",
6769                  &sb->s_uuid, sb_rdonly(sb) ? "ro" : "r/w",
6770                  ext4_quota_mode(sb));
6771
6772         return 0;
6773 }
6774
6775 #ifdef CONFIG_QUOTA
6776 static int ext4_statfs_project(struct super_block *sb,
6777                                kprojid_t projid, struct kstatfs *buf)
6778 {
6779         struct kqid qid;
6780         struct dquot *dquot;
6781         u64 limit;
6782         u64 curblock;
6783
6784         qid = make_kqid_projid(projid);
6785         dquot = dqget(sb, qid);
6786         if (IS_ERR(dquot))
6787                 return PTR_ERR(dquot);
6788         spin_lock(&dquot->dq_dqb_lock);
6789
6790         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6791                              dquot->dq_dqb.dqb_bhardlimit);
6792         limit >>= sb->s_blocksize_bits;
6793
6794         if (limit && buf->f_blocks > limit) {
6795                 curblock = (dquot->dq_dqb.dqb_curspace +
6796                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6797                 buf->f_blocks = limit;
6798                 buf->f_bfree = buf->f_bavail =
6799                         (buf->f_blocks > curblock) ?
6800                          (buf->f_blocks - curblock) : 0;
6801         }
6802
6803         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6804                              dquot->dq_dqb.dqb_ihardlimit);
6805         if (limit && buf->f_files > limit) {
6806                 buf->f_files = limit;
6807                 buf->f_ffree =
6808                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6809                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6810         }
6811
6812         spin_unlock(&dquot->dq_dqb_lock);
6813         dqput(dquot);
6814         return 0;
6815 }
6816 #endif
6817
6818 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6819 {
6820         struct super_block *sb = dentry->d_sb;
6821         struct ext4_sb_info *sbi = EXT4_SB(sb);
6822         struct ext4_super_block *es = sbi->s_es;
6823         ext4_fsblk_t overhead = 0, resv_blocks;
6824         s64 bfree;
6825         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6826
6827         if (!test_opt(sb, MINIX_DF))
6828                 overhead = sbi->s_overhead;
6829
6830         buf->f_type = EXT4_SUPER_MAGIC;
6831         buf->f_bsize = sb->s_blocksize;
6832         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6833         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6834                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6835         /* prevent underflow in case that few free space is available */
6836         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6837         buf->f_bavail = buf->f_bfree -
6838                         (ext4_r_blocks_count(es) + resv_blocks);
6839         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6840                 buf->f_bavail = 0;
6841         buf->f_files = le32_to_cpu(es->s_inodes_count);
6842         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6843         buf->f_namelen = EXT4_NAME_LEN;
6844         buf->f_fsid = uuid_to_fsid(es->s_uuid);
6845
6846 #ifdef CONFIG_QUOTA
6847         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6848             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6849                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6850 #endif
6851         return 0;
6852 }
6853
6854
6855 #ifdef CONFIG_QUOTA
6856
6857 /*
6858  * Helper functions so that transaction is started before we acquire dqio_sem
6859  * to keep correct lock ordering of transaction > dqio_sem
6860  */
6861 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6862 {
6863         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6864 }
6865
6866 static int ext4_write_dquot(struct dquot *dquot)
6867 {
6868         int ret, err;
6869         handle_t *handle;
6870         struct inode *inode;
6871
6872         inode = dquot_to_inode(dquot);
6873         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6874                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6875         if (IS_ERR(handle))
6876                 return PTR_ERR(handle);
6877         ret = dquot_commit(dquot);
6878         err = ext4_journal_stop(handle);
6879         if (!ret)
6880                 ret = err;
6881         return ret;
6882 }
6883
6884 static int ext4_acquire_dquot(struct dquot *dquot)
6885 {
6886         int ret, err;
6887         handle_t *handle;
6888
6889         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6890                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6891         if (IS_ERR(handle))
6892                 return PTR_ERR(handle);
6893         ret = dquot_acquire(dquot);
6894         err = ext4_journal_stop(handle);
6895         if (!ret)
6896                 ret = err;
6897         return ret;
6898 }
6899
6900 static int ext4_release_dquot(struct dquot *dquot)
6901 {
6902         int ret, err;
6903         handle_t *handle;
6904
6905         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6906                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6907         if (IS_ERR(handle)) {
6908                 /* Release dquot anyway to avoid endless cycle in dqput() */
6909                 dquot_release(dquot);
6910                 return PTR_ERR(handle);
6911         }
6912         ret = dquot_release(dquot);
6913         err = ext4_journal_stop(handle);
6914         if (!ret)
6915                 ret = err;
6916         return ret;
6917 }
6918
6919 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6920 {
6921         struct super_block *sb = dquot->dq_sb;
6922
6923         if (ext4_is_quota_journalled(sb)) {
6924                 dquot_mark_dquot_dirty(dquot);
6925                 return ext4_write_dquot(dquot);
6926         } else {
6927                 return dquot_mark_dquot_dirty(dquot);
6928         }
6929 }
6930
6931 static int ext4_write_info(struct super_block *sb, int type)
6932 {
6933         int ret, err;
6934         handle_t *handle;
6935
6936         /* Data block + inode block */
6937         handle = ext4_journal_start_sb(sb, EXT4_HT_QUOTA, 2);
6938         if (IS_ERR(handle))
6939                 return PTR_ERR(handle);
6940         ret = dquot_commit_info(sb, type);
6941         err = ext4_journal_stop(handle);
6942         if (!ret)
6943                 ret = err;
6944         return ret;
6945 }
6946
6947 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6948 {
6949         struct ext4_inode_info *ei = EXT4_I(inode);
6950
6951         /* The first argument of lockdep_set_subclass has to be
6952          * *exactly* the same as the argument to init_rwsem() --- in
6953          * this case, in init_once() --- or lockdep gets unhappy
6954          * because the name of the lock is set using the
6955          * stringification of the argument to init_rwsem().
6956          */
6957         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6958         lockdep_set_subclass(&ei->i_data_sem, subclass);
6959 }
6960
6961 /*
6962  * Standard function to be called on quota_on
6963  */
6964 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6965                          const struct path *path)
6966 {
6967         int err;
6968
6969         if (!test_opt(sb, QUOTA))
6970                 return -EINVAL;
6971
6972         /* Quotafile not on the same filesystem? */
6973         if (path->dentry->d_sb != sb)
6974                 return -EXDEV;
6975
6976         /* Quota already enabled for this file? */
6977         if (IS_NOQUOTA(d_inode(path->dentry)))
6978                 return -EBUSY;
6979
6980         /* Journaling quota? */
6981         if (EXT4_SB(sb)->s_qf_names[type]) {
6982                 /* Quotafile not in fs root? */
6983                 if (path->dentry->d_parent != sb->s_root)
6984                         ext4_msg(sb, KERN_WARNING,
6985                                 "Quota file not on filesystem root. "
6986                                 "Journaled quota will not work");
6987                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6988         } else {
6989                 /*
6990                  * Clear the flag just in case mount options changed since
6991                  * last time.
6992                  */
6993                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6994         }
6995
6996         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6997         err = dquot_quota_on(sb, type, format_id, path);
6998         if (!err) {
6999                 struct inode *inode = d_inode(path->dentry);
7000                 handle_t *handle;
7001
7002                 /*
7003                  * Set inode flags to prevent userspace from messing with quota
7004                  * files. If this fails, we return success anyway since quotas
7005                  * are already enabled and this is not a hard failure.
7006                  */
7007                 inode_lock(inode);
7008                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7009                 if (IS_ERR(handle))
7010                         goto unlock_inode;
7011                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
7012                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
7013                                 S_NOATIME | S_IMMUTABLE);
7014                 err = ext4_mark_inode_dirty(handle, inode);
7015                 ext4_journal_stop(handle);
7016         unlock_inode:
7017                 inode_unlock(inode);
7018                 if (err)
7019                         dquot_quota_off(sb, type);
7020         }
7021         if (err)
7022                 lockdep_set_quota_inode(path->dentry->d_inode,
7023                                              I_DATA_SEM_NORMAL);
7024         return err;
7025 }
7026
7027 static inline bool ext4_check_quota_inum(int type, unsigned long qf_inum)
7028 {
7029         switch (type) {
7030         case USRQUOTA:
7031                 return qf_inum == EXT4_USR_QUOTA_INO;
7032         case GRPQUOTA:
7033                 return qf_inum == EXT4_GRP_QUOTA_INO;
7034         case PRJQUOTA:
7035                 return qf_inum >= EXT4_GOOD_OLD_FIRST_INO;
7036         default:
7037                 BUG();
7038         }
7039 }
7040
7041 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
7042                              unsigned int flags)
7043 {
7044         int err;
7045         struct inode *qf_inode;
7046         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7047                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7048                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7049                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7050         };
7051
7052         BUG_ON(!ext4_has_feature_quota(sb));
7053
7054         if (!qf_inums[type])
7055                 return -EPERM;
7056
7057         if (!ext4_check_quota_inum(type, qf_inums[type])) {
7058                 ext4_error(sb, "Bad quota inum: %lu, type: %d",
7059                                 qf_inums[type], type);
7060                 return -EUCLEAN;
7061         }
7062
7063         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
7064         if (IS_ERR(qf_inode)) {
7065                 ext4_error(sb, "Bad quota inode: %lu, type: %d",
7066                                 qf_inums[type], type);
7067                 return PTR_ERR(qf_inode);
7068         }
7069
7070         /* Don't account quota for quota files to avoid recursion */
7071         qf_inode->i_flags |= S_NOQUOTA;
7072         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
7073         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
7074         if (err)
7075                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
7076         iput(qf_inode);
7077
7078         return err;
7079 }
7080
7081 /* Enable usage tracking for all quota types. */
7082 int ext4_enable_quotas(struct super_block *sb)
7083 {
7084         int type, err = 0;
7085         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7086                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7087                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7088                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7089         };
7090         bool quota_mopt[EXT4_MAXQUOTAS] = {
7091                 test_opt(sb, USRQUOTA),
7092                 test_opt(sb, GRPQUOTA),
7093                 test_opt(sb, PRJQUOTA),
7094         };
7095
7096         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
7097         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
7098                 if (qf_inums[type]) {
7099                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
7100                                 DQUOT_USAGE_ENABLED |
7101                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
7102                         if (err) {
7103                                 ext4_warning(sb,
7104                                         "Failed to enable quota tracking "
7105                                         "(type=%d, err=%d, ino=%lu). "
7106                                         "Please run e2fsck to fix.", type,
7107                                         err, qf_inums[type]);
7108
7109                                 ext4_quotas_off(sb, type);
7110                                 return err;
7111                         }
7112                 }
7113         }
7114         return 0;
7115 }
7116
7117 static int ext4_quota_off(struct super_block *sb, int type)
7118 {
7119         struct inode *inode = sb_dqopt(sb)->files[type];
7120         handle_t *handle;
7121         int err;
7122
7123         /* Force all delayed allocation blocks to be allocated.
7124          * Caller already holds s_umount sem */
7125         if (test_opt(sb, DELALLOC))
7126                 sync_filesystem(sb);
7127
7128         if (!inode || !igrab(inode))
7129                 goto out;
7130
7131         err = dquot_quota_off(sb, type);
7132         if (err || ext4_has_feature_quota(sb))
7133                 goto out_put;
7134         /*
7135          * When the filesystem was remounted read-only first, we cannot cleanup
7136          * inode flags here. Bad luck but people should be using QUOTA feature
7137          * these days anyway.
7138          */
7139         if (sb_rdonly(sb))
7140                 goto out_put;
7141
7142         inode_lock(inode);
7143         /*
7144          * Update modification times of quota files when userspace can
7145          * start looking at them. If we fail, we return success anyway since
7146          * this is not a hard failure and quotas are already disabled.
7147          */
7148         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7149         if (IS_ERR(handle)) {
7150                 err = PTR_ERR(handle);
7151                 goto out_unlock;
7152         }
7153         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
7154         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
7155         inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
7156         err = ext4_mark_inode_dirty(handle, inode);
7157         ext4_journal_stop(handle);
7158 out_unlock:
7159         inode_unlock(inode);
7160 out_put:
7161         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
7162         iput(inode);
7163         return err;
7164 out:
7165         return dquot_quota_off(sb, type);
7166 }
7167
7168 /* Read data from quotafile - avoid pagecache and such because we cannot afford
7169  * acquiring the locks... As quota files are never truncated and quota code
7170  * itself serializes the operations (and no one else should touch the files)
7171  * we don't have to be afraid of races */
7172 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
7173                                size_t len, loff_t off)
7174 {
7175         struct inode *inode = sb_dqopt(sb)->files[type];
7176         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7177         int offset = off & (sb->s_blocksize - 1);
7178         int tocopy;
7179         size_t toread;
7180         struct buffer_head *bh;
7181         loff_t i_size = i_size_read(inode);
7182
7183         if (off > i_size)
7184                 return 0;
7185         if (off+len > i_size)
7186                 len = i_size-off;
7187         toread = len;
7188         while (toread > 0) {
7189                 tocopy = min_t(unsigned long, sb->s_blocksize - offset, toread);
7190                 bh = ext4_bread(NULL, inode, blk, 0);
7191                 if (IS_ERR(bh))
7192                         return PTR_ERR(bh);
7193                 if (!bh)        /* A hole? */
7194                         memset(data, 0, tocopy);
7195                 else
7196                         memcpy(data, bh->b_data+offset, tocopy);
7197                 brelse(bh);
7198                 offset = 0;
7199                 toread -= tocopy;
7200                 data += tocopy;
7201                 blk++;
7202         }
7203         return len;
7204 }
7205
7206 /* Write to quotafile (we know the transaction is already started and has
7207  * enough credits) */
7208 static ssize_t ext4_quota_write(struct super_block *sb, int type,
7209                                 const char *data, size_t len, loff_t off)
7210 {
7211         struct inode *inode = sb_dqopt(sb)->files[type];
7212         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7213         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
7214         int retries = 0;
7215         struct buffer_head *bh;
7216         handle_t *handle = journal_current_handle();
7217
7218         if (!handle) {
7219                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7220                         " cancelled because transaction is not started",
7221                         (unsigned long long)off, (unsigned long long)len);
7222                 return -EIO;
7223         }
7224         /*
7225          * Since we account only one data block in transaction credits,
7226          * then it is impossible to cross a block boundary.
7227          */
7228         if (sb->s_blocksize - offset < len) {
7229                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7230                         " cancelled because not block aligned",
7231                         (unsigned long long)off, (unsigned long long)len);
7232                 return -EIO;
7233         }
7234
7235         do {
7236                 bh = ext4_bread(handle, inode, blk,
7237                                 EXT4_GET_BLOCKS_CREATE |
7238                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
7239         } while (PTR_ERR(bh) == -ENOSPC &&
7240                  ext4_should_retry_alloc(inode->i_sb, &retries));
7241         if (IS_ERR(bh))
7242                 return PTR_ERR(bh);
7243         if (!bh)
7244                 goto out;
7245         BUFFER_TRACE(bh, "get write access");
7246         err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
7247         if (err) {
7248                 brelse(bh);
7249                 return err;
7250         }
7251         lock_buffer(bh);
7252         memcpy(bh->b_data+offset, data, len);
7253         flush_dcache_page(bh->b_page);
7254         unlock_buffer(bh);
7255         err = ext4_handle_dirty_metadata(handle, NULL, bh);
7256         brelse(bh);
7257 out:
7258         if (inode->i_size < off + len) {
7259                 i_size_write(inode, off + len);
7260                 EXT4_I(inode)->i_disksize = inode->i_size;
7261                 err2 = ext4_mark_inode_dirty(handle, inode);
7262                 if (unlikely(err2 && !err))
7263                         err = err2;
7264         }
7265         return err ? err : len;
7266 }
7267 #endif
7268
7269 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
7270 static inline void register_as_ext2(void)
7271 {
7272         int err = register_filesystem(&ext2_fs_type);
7273         if (err)
7274                 printk(KERN_WARNING
7275                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7276 }
7277
7278 static inline void unregister_as_ext2(void)
7279 {
7280         unregister_filesystem(&ext2_fs_type);
7281 }
7282
7283 static inline int ext2_feature_set_ok(struct super_block *sb)
7284 {
7285         if (ext4_has_unknown_ext2_incompat_features(sb))
7286                 return 0;
7287         if (sb_rdonly(sb))
7288                 return 1;
7289         if (ext4_has_unknown_ext2_ro_compat_features(sb))
7290                 return 0;
7291         return 1;
7292 }
7293 #else
7294 static inline void register_as_ext2(void) { }
7295 static inline void unregister_as_ext2(void) { }
7296 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7297 #endif
7298
7299 static inline void register_as_ext3(void)
7300 {
7301         int err = register_filesystem(&ext3_fs_type);
7302         if (err)
7303                 printk(KERN_WARNING
7304                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7305 }
7306
7307 static inline void unregister_as_ext3(void)
7308 {
7309         unregister_filesystem(&ext3_fs_type);
7310 }
7311
7312 static inline int ext3_feature_set_ok(struct super_block *sb)
7313 {
7314         if (ext4_has_unknown_ext3_incompat_features(sb))
7315                 return 0;
7316         if (!ext4_has_feature_journal(sb))
7317                 return 0;
7318         if (sb_rdonly(sb))
7319                 return 1;
7320         if (ext4_has_unknown_ext3_ro_compat_features(sb))
7321                 return 0;
7322         return 1;
7323 }
7324
7325 static void ext4_kill_sb(struct super_block *sb)
7326 {
7327         struct ext4_sb_info *sbi = EXT4_SB(sb);
7328         struct bdev_handle *handle = sbi ? sbi->s_journal_bdev_handle : NULL;
7329
7330         kill_block_super(sb);
7331
7332         if (handle)
7333                 bdev_release(handle);
7334 }
7335
7336 static struct file_system_type ext4_fs_type = {
7337         .owner                  = THIS_MODULE,
7338         .name                   = "ext4",
7339         .init_fs_context        = ext4_init_fs_context,
7340         .parameters             = ext4_param_specs,
7341         .kill_sb                = ext4_kill_sb,
7342         .fs_flags               = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
7343 };
7344 MODULE_ALIAS_FS("ext4");
7345
7346 /* Shared across all ext4 file systems */
7347 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
7348
7349 static int __init ext4_init_fs(void)
7350 {
7351         int i, err;
7352
7353         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7354         ext4_li_info = NULL;
7355
7356         /* Build-time check for flags consistency */
7357         ext4_check_flag_values();
7358
7359         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
7360                 init_waitqueue_head(&ext4__ioend_wq[i]);
7361
7362         err = ext4_init_es();
7363         if (err)
7364                 return err;
7365
7366         err = ext4_init_pending();
7367         if (err)
7368                 goto out7;
7369
7370         err = ext4_init_post_read_processing();
7371         if (err)
7372                 goto out6;
7373
7374         err = ext4_init_pageio();
7375         if (err)
7376                 goto out5;
7377
7378         err = ext4_init_system_zone();
7379         if (err)
7380                 goto out4;
7381
7382         err = ext4_init_sysfs();
7383         if (err)
7384                 goto out3;
7385
7386         err = ext4_init_mballoc();
7387         if (err)
7388                 goto out2;
7389         err = init_inodecache();
7390         if (err)
7391                 goto out1;
7392
7393         err = ext4_fc_init_dentry_cache();
7394         if (err)
7395                 goto out05;
7396
7397         register_as_ext3();
7398         register_as_ext2();
7399         err = register_filesystem(&ext4_fs_type);
7400         if (err)
7401                 goto out;
7402
7403         return 0;
7404 out:
7405         unregister_as_ext2();
7406         unregister_as_ext3();
7407         ext4_fc_destroy_dentry_cache();
7408 out05:
7409         destroy_inodecache();
7410 out1:
7411         ext4_exit_mballoc();
7412 out2:
7413         ext4_exit_sysfs();
7414 out3:
7415         ext4_exit_system_zone();
7416 out4:
7417         ext4_exit_pageio();
7418 out5:
7419         ext4_exit_post_read_processing();
7420 out6:
7421         ext4_exit_pending();
7422 out7:
7423         ext4_exit_es();
7424
7425         return err;
7426 }
7427
7428 static void __exit ext4_exit_fs(void)
7429 {
7430         ext4_destroy_lazyinit_thread();
7431         unregister_as_ext2();
7432         unregister_as_ext3();
7433         unregister_filesystem(&ext4_fs_type);
7434         ext4_fc_destroy_dentry_cache();
7435         destroy_inodecache();
7436         ext4_exit_mballoc();
7437         ext4_exit_sysfs();
7438         ext4_exit_system_zone();
7439         ext4_exit_pageio();
7440         ext4_exit_post_read_processing();
7441         ext4_exit_es();
7442         ext4_exit_pending();
7443 }
7444
7445 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7446 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7447 MODULE_LICENSE("GPL");
7448 MODULE_SOFTDEP("pre: crc32c");
7449 module_init(ext4_init_fs)
7450 module_exit(ext4_exit_fs)