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 const struct fs_parameter_spec ext4_param_specs[];
  97
  98 /*
  99  * Lock ordering
 100  *
 101  * page fault path:
 102  * mmap_lock -> sb_start_pagefault -> invalidate_lock (r) -> transaction start
 103  *   -> page lock -> i_data_sem (rw)
 104  *
 105  * buffered write path:
 106  * sb_start_write -> i_mutex -> mmap_lock
 107  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 108  *   i_data_sem (rw)
 109  *
 110  * truncate:
 111  * sb_start_write -> i_mutex -> invalidate_lock (w) -> i_mmap_rwsem (w) ->
 112  *   page lock
 113  * sb_start_write -> i_mutex -> invalidate_lock (w) -> transaction start ->
 114  *   i_data_sem (rw)
 115  *
 116  * direct IO:
 117  * sb_start_write -> i_mutex -> mmap_lock
 118  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 119  *
 120  * writepages:
 121  * transaction start -> page lock(s) -> i_data_sem (rw)
 122  */
 123
 124 static const struct fs_context_operations ext4_context_ops = {
 125         .parse_param    = ext4_parse_param,
 126         .get_tree       = ext4_get_tree,
 127         .reconfigure    = ext4_reconfigure,
 128         .free           = ext4_fc_free,
 129 };
 130
 131
 132 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 133 static struct file_system_type ext2_fs_type = {
 134         .owner                  = THIS_MODULE,
 135         .name                   = "ext2",
 136         .init_fs_context        = ext4_init_fs_context,
 137         .parameters             = ext4_param_specs,
 138         .kill_sb                = kill_block_super,
 139         .fs_flags               = FS_REQUIRES_DEV,
 140 };
 141 MODULE_ALIAS_FS("ext2");
 142 MODULE_ALIAS("ext2");
 143 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 144 #else
 145 #define IS_EXT2_SB(sb) (0)
 146 #endif
 147
 148
 149 static struct file_system_type ext3_fs_type = {
 150         .owner                  = THIS_MODULE,
 151         .name                   = "ext3",
 152         .init_fs_context        = ext4_init_fs_context,
 153         .parameters             = ext4_param_specs,
 154         .kill_sb                = kill_block_super,
 155         .fs_flags               = FS_REQUIRES_DEV,
 156 };
 157 MODULE_ALIAS_FS("ext3");
 158 MODULE_ALIAS("ext3");
 159 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 160
 161
 162 static inline void __ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
 163                                   bh_end_io_t *end_io)
 164 {
 165         /*
 166          * buffer's verified bit is no longer valid after reading from
 167          * disk again due to write out error, clear it to make sure we
 168          * recheck the buffer contents.
 169          */
 170         clear_buffer_verified(bh);
 171
 172         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
 173         get_bh(bh);
 174         submit_bh(REQ_OP_READ | op_flags, bh);
 175 }
 176
 177 void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
 178                          bh_end_io_t *end_io)
 179 {
 180         BUG_ON(!buffer_locked(bh));
 181
 182         if (ext4_buffer_uptodate(bh)) {
 183                 unlock_buffer(bh);
 184                 return;
 185         }
 186         __ext4_read_bh(bh, op_flags, end_io);
 187 }
 188
 189 int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags, bh_end_io_t *end_io)
 190 {
 191         BUG_ON(!buffer_locked(bh));
 192
 193         if (ext4_buffer_uptodate(bh)) {
 194                 unlock_buffer(bh);
 195                 return 0;
 196         }
 197
 198         __ext4_read_bh(bh, op_flags, end_io);
 199
 200         wait_on_buffer(bh);
 201         if (buffer_uptodate(bh))
 202                 return 0;
 203         return -EIO;
 204 }
 205
 206 int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait)
 207 {
 208         lock_buffer(bh);
 209         if (!wait) {
 210                 ext4_read_bh_nowait(bh, op_flags, NULL);
 211                 return 0;
 212         }
 213         return ext4_read_bh(bh, op_flags, NULL);
 214 }
 215
 216 /*
 217  * This works like __bread_gfp() except it uses ERR_PTR for error
 218  * returns.  Currently with sb_bread it's impossible to distinguish
 219  * between ENOMEM and EIO situations (since both result in a NULL
 220  * return.
 221  */
 222 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 223                                                sector_t block,
 224                                                blk_opf_t op_flags, gfp_t gfp)
 225 {
 226         struct buffer_head *bh;
 227         int ret;
 228
 229         bh = sb_getblk_gfp(sb, block, gfp);
 230         if (bh == NULL)
 231                 return ERR_PTR(-ENOMEM);
 232         if (ext4_buffer_uptodate(bh))
 233                 return bh;
 234
 235         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
 236         if (ret) {
 237                 put_bh(bh);
 238                 return ERR_PTR(ret);
 239         }
 240         return bh;
 241 }
 242
 243 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 244                                    blk_opf_t op_flags)
 245 {
 246         return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
 247 }
 248
 249 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 250                                             sector_t block)
 251 {
 252         return __ext4_sb_bread_gfp(sb, block, 0, 0);
 253 }
 254
 255 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
 256 {
 257         struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
 258
 259         if (likely(bh)) {
 260                 if (trylock_buffer(bh))
 261                         ext4_read_bh_nowait(bh, REQ_RAHEAD, NULL);
 262                 brelse(bh);
 263         }
 264 }
 265
 266 static int ext4_verify_csum_type(struct super_block *sb,
 267                                  struct ext4_super_block *es)
 268 {
 269         if (!ext4_has_feature_metadata_csum(sb))
 270                 return 1;
 271
 272         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 273 }
 274
 275 __le32 ext4_superblock_csum(struct super_block *sb,
 276                             struct ext4_super_block *es)
 277 {
 278         struct ext4_sb_info *sbi = EXT4_SB(sb);
 279         int offset = offsetof(struct ext4_super_block, s_checksum);
 280         __u32 csum;
 281
 282         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 283
 284         return cpu_to_le32(csum);
 285 }
 286
 287 static int ext4_superblock_csum_verify(struct super_block *sb,
 288                                        struct ext4_super_block *es)
 289 {
 290         if (!ext4_has_metadata_csum(sb))
 291                 return 1;
 292
 293         return es->s_checksum == ext4_superblock_csum(sb, es);
 294 }
 295
 296 void ext4_superblock_csum_set(struct super_block *sb)
 297 {
 298         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 299
 300         if (!ext4_has_metadata_csum(sb))
 301                 return;
 302
 303         es->s_checksum = ext4_superblock_csum(sb, es);
 304 }
 305
 306 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 307                                struct ext4_group_desc *bg)
 308 {
 309         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 310                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 311                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 312 }
 313
 314 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 315                                struct ext4_group_desc *bg)
 316 {
 317         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 318                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 319                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 320 }
 321
 322 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 323                               struct ext4_group_desc *bg)
 324 {
 325         return le32_to_cpu(bg->bg_inode_table_lo) |
 326                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 327                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 328 }
 329
 330 __u32 ext4_free_group_clusters(struct super_block *sb,
 331                                struct ext4_group_desc *bg)
 332 {
 333         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 334                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 335                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 336 }
 337
 338 __u32 ext4_free_inodes_count(struct super_block *sb,
 339                               struct ext4_group_desc *bg)
 340 {
 341         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 342                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 343                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 344 }
 345
 346 __u32 ext4_used_dirs_count(struct super_block *sb,
 347                               struct ext4_group_desc *bg)
 348 {
 349         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 350                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 351                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 352 }
 353
 354 __u32 ext4_itable_unused_count(struct super_block *sb,
 355                               struct ext4_group_desc *bg)
 356 {
 357         return le16_to_cpu(bg->bg_itable_unused_lo) |
 358                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 359                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 360 }
 361
 362 void ext4_block_bitmap_set(struct super_block *sb,
 363                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 364 {
 365         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 366         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 367                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 368 }
 369
 370 void ext4_inode_bitmap_set(struct super_block *sb,
 371                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 372 {
 373         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 374         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 375                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 376 }
 377
 378 void ext4_inode_table_set(struct super_block *sb,
 379                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 380 {
 381         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 382         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 383                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 384 }
 385
 386 void ext4_free_group_clusters_set(struct super_block *sb,
 387                                   struct ext4_group_desc *bg, __u32 count)
 388 {
 389         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 390         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 391                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 392 }
 393
 394 void ext4_free_inodes_set(struct super_block *sb,
 395                           struct ext4_group_desc *bg, __u32 count)
 396 {
 397         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 398         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 399                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 400 }
 401
 402 void ext4_used_dirs_set(struct super_block *sb,
 403                           struct ext4_group_desc *bg, __u32 count)
 404 {
 405         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 406         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 407                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 408 }
 409
 410 void ext4_itable_unused_set(struct super_block *sb,
 411                           struct ext4_group_desc *bg, __u32 count)
 412 {
 413         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 414         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 415                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 416 }
 417
 418 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi, time64_t now)
 419 {
 420         now = clamp_val(now, 0, (1ull << 40) - 1);
 421
 422         *lo = cpu_to_le32(lower_32_bits(now));
 423         *hi = upper_32_bits(now);
 424 }
 425
 426 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 427 {
 428         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 429 }
 430 #define ext4_update_tstamp(es, tstamp) \
 431         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi, \
 432                              ktime_get_real_seconds())
 433 #define ext4_get_tstamp(es, tstamp) \
 434         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 435
 436 /*
 437  * The del_gendisk() function uninitializes the disk-specific data
 438  * structures, including the bdi structure, without telling anyone
 439  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 440  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 441  * This is a kludge to prevent these oops until we can put in a proper
 442  * hook in del_gendisk() to inform the VFS and file system layers.
 443  */
 444 static int block_device_ejected(struct super_block *sb)
 445 {
 446         struct inode *bd_inode = sb->s_bdev->bd_inode;
 447         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 448
 449         return bdi->dev == NULL;
 450 }
 451
 452 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 453 {
 454         struct super_block              *sb = journal->j_private;
 455         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 456         int                             error = is_journal_aborted(journal);
 457         struct ext4_journal_cb_entry    *jce;
 458
 459         BUG_ON(txn->t_state == T_FINISHED);
 460
 461         ext4_process_freed_data(sb, txn->t_tid);
 462
 463         spin_lock(&sbi->s_md_lock);
 464         while (!list_empty(&txn->t_private_list)) {
 465                 jce = list_entry(txn->t_private_list.next,
 466                                  struct ext4_journal_cb_entry, jce_list);
 467                 list_del_init(&jce->jce_list);
 468                 spin_unlock(&sbi->s_md_lock);
 469                 jce->jce_func(sb, jce, error);
 470                 spin_lock(&sbi->s_md_lock);
 471         }
 472         spin_unlock(&sbi->s_md_lock);
 473 }
 474
 475 /*
 476  * This writepage callback for write_cache_pages()
 477  * takes care of a few cases after page cleaning.
 478  *
 479  * write_cache_pages() already checks for dirty pages
 480  * and calls clear_page_dirty_for_io(), which we want,
 481  * to write protect the pages.
 482  *
 483  * However, we may have to redirty a page (see below.)
 484  */
 485 static int ext4_journalled_writepage_callback(struct page *page,
 486                                               struct writeback_control *wbc,
 487                                               void *data)
 488 {
 489         transaction_t *transaction = (transaction_t *) data;
 490         struct buffer_head *bh, *head;
 491         struct journal_head *jh;
 492
 493         bh = head = page_buffers(page);
 494         do {
 495                 /*
 496                  * We have to redirty a page in these cases:
 497                  * 1) If buffer is dirty, it means the page was dirty because it
 498                  * contains a buffer that needs checkpointing. So the dirty bit
 499                  * needs to be preserved so that checkpointing writes the buffer
 500                  * properly.
 501                  * 2) If buffer is not part of the committing transaction
 502                  * (we may have just accidentally come across this buffer because
 503                  * inode range tracking is not exact) or if the currently running
 504                  * transaction already contains this buffer as well, dirty bit
 505                  * needs to be preserved so that the buffer gets writeprotected
 506                  * properly on running transaction's commit.
 507                  */
 508                 jh = bh2jh(bh);
 509                 if (buffer_dirty(bh) ||
 510                     (jh && (jh->b_transaction != transaction ||
 511                             jh->b_next_transaction))) {
 512                         redirty_page_for_writepage(wbc, page);
 513                         goto out;
 514                 }
 515         } while ((bh = bh->b_this_page) != head);
 516
 517 out:
 518         return AOP_WRITEPAGE_ACTIVATE;
 519 }
 520
 521 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
 522 {
 523         struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
 524         struct writeback_control wbc = {
 525                 .sync_mode =  WB_SYNC_ALL,
 526                 .nr_to_write = LONG_MAX,
 527                 .range_start = jinode->i_dirty_start,
 528                 .range_end = jinode->i_dirty_end,
 529         };
 530
 531         return write_cache_pages(mapping, &wbc,
 532                                  ext4_journalled_writepage_callback,
 533                                  jinode->i_transaction);
 534 }
 535
 536 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
 537 {
 538         int ret;
 539
 540         if (ext4_should_journal_data(jinode->i_vfs_inode))
 541                 ret = ext4_journalled_submit_inode_data_buffers(jinode);
 542         else
 543                 ret = jbd2_journal_submit_inode_data_buffers(jinode);
 544
 545         return ret;
 546 }
 547
 548 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
 549 {
 550         int ret = 0;
 551
 552         if (!ext4_should_journal_data(jinode->i_vfs_inode))
 553                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
 554
 555         return ret;
 556 }
 557
 558 static bool system_going_down(void)
 559 {
 560         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 561                 || system_state == SYSTEM_RESTART;
 562 }
 563
 564 struct ext4_err_translation {
 565         int code;
 566         int errno;
 567 };
 568
 569 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
 570
 571 static struct ext4_err_translation err_translation[] = {
 572         EXT4_ERR_TRANSLATE(EIO),
 573         EXT4_ERR_TRANSLATE(ENOMEM),
 574         EXT4_ERR_TRANSLATE(EFSBADCRC),
 575         EXT4_ERR_TRANSLATE(EFSCORRUPTED),
 576         EXT4_ERR_TRANSLATE(ENOSPC),
 577         EXT4_ERR_TRANSLATE(ENOKEY),
 578         EXT4_ERR_TRANSLATE(EROFS),
 579         EXT4_ERR_TRANSLATE(EFBIG),
 580         EXT4_ERR_TRANSLATE(EEXIST),
 581         EXT4_ERR_TRANSLATE(ERANGE),
 582         EXT4_ERR_TRANSLATE(EOVERFLOW),
 583         EXT4_ERR_TRANSLATE(EBUSY),
 584         EXT4_ERR_TRANSLATE(ENOTDIR),
 585         EXT4_ERR_TRANSLATE(ENOTEMPTY),
 586         EXT4_ERR_TRANSLATE(ESHUTDOWN),
 587         EXT4_ERR_TRANSLATE(EFAULT),
 588 };
 589
 590 static int ext4_errno_to_code(int errno)
 591 {
 592         int i;
 593
 594         for (i = 0; i < ARRAY_SIZE(err_translation); i++)
 595                 if (err_translation[i].errno == errno)
 596                         return err_translation[i].code;
 597         return EXT4_ERR_UNKNOWN;
 598 }
 599
 600 static void save_error_info(struct super_block *sb, int error,
 601                             __u32 ino, __u64 block,
 602                             const char *func, unsigned int line)
 603 {
 604         struct ext4_sb_info *sbi = EXT4_SB(sb);
 605
 606         /* We default to EFSCORRUPTED error... */
 607         if (error == 0)
 608                 error = EFSCORRUPTED;
 609
 610         spin_lock(&sbi->s_error_lock);
 611         sbi->s_add_error_count++;
 612         sbi->s_last_error_code = error;
 613         sbi->s_last_error_line = line;
 614         sbi->s_last_error_ino = ino;
 615         sbi->s_last_error_block = block;
 616         sbi->s_last_error_func = func;
 617         sbi->s_last_error_time = ktime_get_real_seconds();
 618         if (!sbi->s_first_error_time) {
 619                 sbi->s_first_error_code = error;
 620                 sbi->s_first_error_line = line;
 621                 sbi->s_first_error_ino = ino;
 622                 sbi->s_first_error_block = block;
 623                 sbi->s_first_error_func = func;
 624                 sbi->s_first_error_time = sbi->s_last_error_time;
 625         }
 626         spin_unlock(&sbi->s_error_lock);
 627 }
 628
 629 /* Deal with the reporting of failure conditions on a filesystem such as
 630  * inconsistencies detected or read IO failures.
 631  *
 632  * On ext2, we can store the error state of the filesystem in the
 633  * superblock.  That is not possible on ext4, because we may have other
 634  * write ordering constraints on the superblock which prevent us from
 635  * writing it out straight away; and given that the journal is about to
 636  * be aborted, we can't rely on the current, or future, transactions to
 637  * write out the superblock safely.
 638  *
 639  * We'll just use the jbd2_journal_abort() error code to record an error in
 640  * the journal instead.  On recovery, the journal will complain about
 641  * that error until we've noted it down and cleared it.
 642  *
 643  * If force_ro is set, we unconditionally force the filesystem into an
 644  * ABORT|READONLY state, unless the error response on the fs has been set to
 645  * panic in which case we take the easy way out and panic immediately. This is
 646  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
 647  * at a critical moment in log management.
 648  */
 649 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
 650                               __u32 ino, __u64 block,
 651                               const char *func, unsigned int line)
 652 {
 653         journal_t *journal = EXT4_SB(sb)->s_journal;
 654         bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
 655
 656         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 657         if (test_opt(sb, WARN_ON_ERROR))
 658                 WARN_ON_ONCE(1);
 659
 660         if (!continue_fs && !sb_rdonly(sb)) {
 661                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
 662                 if (journal)
 663                         jbd2_journal_abort(journal, -EIO);
 664         }
 665
 666         if (!bdev_read_only(sb->s_bdev)) {
 667                 save_error_info(sb, error, ino, block, func, line);
 668                 /*
 669                  * In case the fs should keep running, we need to writeout
 670                  * superblock through the journal. Due to lock ordering
 671                  * constraints, it may not be safe to do it right here so we
 672                  * defer superblock flushing to a workqueue.
 673                  */
 674                 if (continue_fs && journal)
 675                         schedule_work(&EXT4_SB(sb)->s_error_work);
 676                 else
 677                         ext4_commit_super(sb);
 678         }
 679
 680         /*
 681          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 682          * could panic during 'reboot -f' as the underlying device got already
 683          * disabled.
 684          */
 685         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 686                 panic("EXT4-fs (device %s): panic forced after error\n",
 687                         sb->s_id);
 688         }
 689
 690         if (sb_rdonly(sb) || continue_fs)
 691                 return;
 692
 693         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 694         /*
 695          * Make sure updated value of ->s_mount_flags will be visible before
 696          * ->s_flags update
 697          */
 698         smp_wmb();
 699         sb->s_flags |= SB_RDONLY;
 700 }
 701
 702 static void flush_stashed_error_work(struct work_struct *work)
 703 {
 704         struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
 705                                                 s_error_work);
 706         journal_t *journal = sbi->s_journal;
 707         handle_t *handle;
 708
 709         /*
 710          * If the journal is still running, we have to write out superblock
 711          * through the journal to avoid collisions of other journalled sb
 712          * updates.
 713          *
 714          * We use directly jbd2 functions here to avoid recursing back into
 715          * ext4 error handling code during handling of previous errors.
 716          */
 717         if (!sb_rdonly(sbi->s_sb) && journal) {
 718                 struct buffer_head *sbh = sbi->s_sbh;
 719                 handle = jbd2_journal_start(journal, 1);
 720                 if (IS_ERR(handle))
 721                         goto write_directly;
 722                 if (jbd2_journal_get_write_access(handle, sbh)) {
 723                         jbd2_journal_stop(handle);
 724                         goto write_directly;
 725                 }
 726                 ext4_update_super(sbi->s_sb);
 727                 if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
 728                         ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
 729                                  "superblock detected");
 730                         clear_buffer_write_io_error(sbh);
 731                         set_buffer_uptodate(sbh);
 732                 }
 733
 734                 if (jbd2_journal_dirty_metadata(handle, sbh)) {
 735                         jbd2_journal_stop(handle);
 736                         goto write_directly;
 737                 }
 738                 jbd2_journal_stop(handle);
 739                 ext4_notify_error_sysfs(sbi);
 740                 return;
 741         }
 742 write_directly:
 743         /*
 744          * Write through journal failed. Write sb directly to get error info
 745          * out and hope for the best.
 746          */
 747         ext4_commit_super(sbi->s_sb);
 748         ext4_notify_error_sysfs(sbi);
 749 }
 750
 751 #define ext4_error_ratelimit(sb)                                        \
 752                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 753                              "EXT4-fs error")
 754
 755 void __ext4_error(struct super_block *sb, const char *function,
 756                   unsigned int line, bool force_ro, int error, __u64 block,
 757                   const char *fmt, ...)
 758 {
 759         struct va_format vaf;
 760         va_list args;
 761
 762         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 763                 return;
 764
 765         trace_ext4_error(sb, function, line);
 766         if (ext4_error_ratelimit(sb)) {
 767                 va_start(args, fmt);
 768                 vaf.fmt = fmt;
 769                 vaf.va = &args;
 770                 printk(KERN_CRIT
 771                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 772                        sb->s_id, function, line, current->comm, &vaf);
 773                 va_end(args);
 774         }
 775         fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
 776
 777         ext4_handle_error(sb, force_ro, error, 0, block, function, line);
 778 }
 779
 780 void __ext4_error_inode(struct inode *inode, const char *function,
 781                         unsigned int line, ext4_fsblk_t block, int error,
 782                         const char *fmt, ...)
 783 {
 784         va_list args;
 785         struct va_format vaf;
 786
 787         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 788                 return;
 789
 790         trace_ext4_error(inode->i_sb, function, line);
 791         if (ext4_error_ratelimit(inode->i_sb)) {
 792                 va_start(args, fmt);
 793                 vaf.fmt = fmt;
 794                 vaf.va = &args;
 795                 if (block)
 796                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 797                                "inode #%lu: block %llu: comm %s: %pV\n",
 798                                inode->i_sb->s_id, function, line, inode->i_ino,
 799                                block, current->comm, &vaf);
 800                 else
 801                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 802                                "inode #%lu: comm %s: %pV\n",
 803                                inode->i_sb->s_id, function, line, inode->i_ino,
 804                                current->comm, &vaf);
 805                 va_end(args);
 806         }
 807         fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
 808
 809         ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
 810                           function, line);
 811 }
 812
 813 void __ext4_error_file(struct file *file, const char *function,
 814                        unsigned int line, ext4_fsblk_t block,
 815                        const char *fmt, ...)
 816 {
 817         va_list args;
 818         struct va_format vaf;
 819         struct inode *inode = file_inode(file);
 820         char pathname[80], *path;
 821
 822         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 823                 return;
 824
 825         trace_ext4_error(inode->i_sb, function, line);
 826         if (ext4_error_ratelimit(inode->i_sb)) {
 827                 path = file_path(file, pathname, sizeof(pathname));
 828                 if (IS_ERR(path))
 829                         path = "(unknown)";
 830                 va_start(args, fmt);
 831                 vaf.fmt = fmt;
 832                 vaf.va = &args;
 833                 if (block)
 834                         printk(KERN_CRIT
 835                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 836                                "block %llu: comm %s: path %s: %pV\n",
 837                                inode->i_sb->s_id, function, line, inode->i_ino,
 838                                block, current->comm, path, &vaf);
 839                 else
 840                         printk(KERN_CRIT
 841                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 842                                "comm %s: path %s: %pV\n",
 843                                inode->i_sb->s_id, function, line, inode->i_ino,
 844                                current->comm, path, &vaf);
 845                 va_end(args);
 846         }
 847         fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
 848
 849         ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
 850                           function, line);
 851 }
 852
 853 const char *ext4_decode_error(struct super_block *sb, int errno,
 854                               char nbuf[16])
 855 {
 856         char *errstr = NULL;
 857
 858         switch (errno) {
 859         case -EFSCORRUPTED:
 860                 errstr = "Corrupt filesystem";
 861                 break;
 862         case -EFSBADCRC:
 863                 errstr = "Filesystem failed CRC";
 864                 break;
 865         case -EIO:
 866                 errstr = "IO failure";
 867                 break;
 868         case -ENOMEM:
 869                 errstr = "Out of memory";
 870                 break;
 871         case -EROFS:
 872                 if (!sb || (EXT4_SB(sb)->s_journal &&
 873                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 874                         errstr = "Journal has aborted";
 875                 else
 876                         errstr = "Readonly filesystem";
 877                 break;
 878         default:
 879                 /* If the caller passed in an extra buffer for unknown
 880                  * errors, textualise them now.  Else we just return
 881                  * NULL. */
 882                 if (nbuf) {
 883                         /* Check for truncated error codes... */
 884                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 885                                 errstr = nbuf;
 886                 }
 887                 break;
 888         }
 889
 890         return errstr;
 891 }
 892
 893 /* __ext4_std_error decodes expected errors from journaling functions
 894  * automatically and invokes the appropriate error response.  */
 895
 896 void __ext4_std_error(struct super_block *sb, const char *function,
 897                       unsigned int line, int errno)
 898 {
 899         char nbuf[16];
 900         const char *errstr;
 901
 902         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 903                 return;
 904
 905         /* Special case: if the error is EROFS, and we're not already
 906          * inside a transaction, then there's really no point in logging
 907          * an error. */
 908         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 909                 return;
 910
 911         if (ext4_error_ratelimit(sb)) {
 912                 errstr = ext4_decode_error(sb, errno, nbuf);
 913                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 914                        sb->s_id, function, line, errstr);
 915         }
 916         fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
 917
 918         ext4_handle_error(sb, false, -errno, 0, 0, function, line);
 919 }
 920
 921 void __ext4_msg(struct super_block *sb,
 922                 const char *prefix, const char *fmt, ...)
 923 {
 924         struct va_format vaf;
 925         va_list args;
 926
 927         if (sb) {
 928                 atomic_inc(&EXT4_SB(sb)->s_msg_count);
 929                 if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state),
 930                                   "EXT4-fs"))
 931                         return;
 932         }
 933
 934         va_start(args, fmt);
 935         vaf.fmt = fmt;
 936         vaf.va = &args;
 937         if (sb)
 938                 printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 939         else
 940                 printk("%sEXT4-fs: %pV\n", prefix, &vaf);
 941         va_end(args);
 942 }
 943
 944 static int ext4_warning_ratelimit(struct super_block *sb)
 945 {
 946         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 947         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 948                             "EXT4-fs warning");
 949 }
 950
 951 void __ext4_warning(struct super_block *sb, const char *function,
 952                     unsigned int line, const char *fmt, ...)
 953 {
 954         struct va_format vaf;
 955         va_list args;
 956
 957         if (!ext4_warning_ratelimit(sb))
 958                 return;
 959
 960         va_start(args, fmt);
 961         vaf.fmt = fmt;
 962         vaf.va = &args;
 963         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 964                sb->s_id, function, line, &vaf);
 965         va_end(args);
 966 }
 967
 968 void __ext4_warning_inode(const struct inode *inode, const char *function,
 969                           unsigned int line, const char *fmt, ...)
 970 {
 971         struct va_format vaf;
 972         va_list args;
 973
 974         if (!ext4_warning_ratelimit(inode->i_sb))
 975                 return;
 976
 977         va_start(args, fmt);
 978         vaf.fmt = fmt;
 979         vaf.va = &args;
 980         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 981                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 982                function, line, inode->i_ino, current->comm, &vaf);
 983         va_end(args);
 984 }
 985
 986 void __ext4_grp_locked_error(const char *function, unsigned int line,
 987                              struct super_block *sb, ext4_group_t grp,
 988                              unsigned long ino, ext4_fsblk_t block,
 989                              const char *fmt, ...)
 990 __releases(bitlock)
 991 __acquires(bitlock)
 992 {
 993         struct va_format vaf;
 994         va_list args;
 995
 996         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 997                 return;
 998
 999         trace_ext4_error(sb, function, line);
1000         if (ext4_error_ratelimit(sb)) {
1001                 va_start(args, fmt);
1002                 vaf.fmt = fmt;
1003                 vaf.va = &args;
1004                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1005                        sb->s_id, function, line, grp);
1006                 if (ino)
1007                         printk(KERN_CONT "inode %lu: ", ino);
1008                 if (block)
1009                         printk(KERN_CONT "block %llu:",
1010                                (unsigned long long) block);
1011                 printk(KERN_CONT "%pV\n", &vaf);
1012                 va_end(args);
1013         }
1014
1015         if (test_opt(sb, ERRORS_CONT)) {
1016                 if (test_opt(sb, WARN_ON_ERROR))
1017                         WARN_ON_ONCE(1);
1018                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
1019                 if (!bdev_read_only(sb->s_bdev)) {
1020                         save_error_info(sb, EFSCORRUPTED, ino, block, function,
1021                                         line);
1022                         schedule_work(&EXT4_SB(sb)->s_error_work);
1023                 }
1024                 return;
1025         }
1026         ext4_unlock_group(sb, grp);
1027         ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1028         /*
1029          * We only get here in the ERRORS_RO case; relocking the group
1030          * may be dangerous, but nothing bad will happen since the
1031          * filesystem will have already been marked read/only and the
1032          * journal has been aborted.  We return 1 as a hint to callers
1033          * who might what to use the return value from
1034          * ext4_grp_locked_error() to distinguish between the
1035          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1036          * aggressively from the ext4 function in question, with a
1037          * more appropriate error code.
1038          */
1039         ext4_lock_group(sb, grp);
1040         return;
1041 }
1042
1043 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1044                                      ext4_group_t group,
1045                                      unsigned int flags)
1046 {
1047         struct ext4_sb_info *sbi = EXT4_SB(sb);
1048         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1049         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1050         int ret;
1051
1052         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1053                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1054                                             &grp->bb_state);
1055                 if (!ret)
1056                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1057                                            grp->bb_free);
1058         }
1059
1060         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1061                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1062                                             &grp->bb_state);
1063                 if (!ret && gdp) {
1064                         int count;
1065
1066                         count = ext4_free_inodes_count(sb, gdp);
1067                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1068                                            count);
1069                 }
1070         }
1071 }
1072
1073 void ext4_update_dynamic_rev(struct super_block *sb)
1074 {
1075         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1076
1077         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1078                 return;
1079
1080         ext4_warning(sb,
1081                      "updating to rev %d because of new feature flag, "
1082                      "running e2fsck is recommended",
1083                      EXT4_DYNAMIC_REV);
1084
1085         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1086         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1087         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1088         /* leave es->s_feature_*compat flags alone */
1089         /* es->s_uuid will be set by e2fsck if empty */
1090
1091         /*
1092          * The rest of the superblock fields should be zero, and if not it
1093          * means they are likely already in use, so leave them alone.  We
1094          * can leave it up to e2fsck to clean up any inconsistencies there.
1095          */
1096 }
1097
1098 /*
1099  * Open the external journal device
1100  */
1101 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1102 {
1103         struct block_device *bdev;
1104
1105         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1106         if (IS_ERR(bdev))
1107                 goto fail;
1108         return bdev;
1109
1110 fail:
1111         ext4_msg(sb, KERN_ERR,
1112                  "failed to open journal device unknown-block(%u,%u) %ld",
1113                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1114         return NULL;
1115 }
1116
1117 /*
1118  * Release the journal device
1119  */
1120 static void ext4_blkdev_put(struct block_device *bdev)
1121 {
1122         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1123 }
1124
1125 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1126 {
1127         struct block_device *bdev;
1128         bdev = sbi->s_journal_bdev;
1129         if (bdev) {
1130                 ext4_blkdev_put(bdev);
1131                 sbi->s_journal_bdev = NULL;
1132         }
1133 }
1134
1135 static inline struct inode *orphan_list_entry(struct list_head *l)
1136 {
1137         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1138 }
1139
1140 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1141 {
1142         struct list_head *l;
1143
1144         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1145                  le32_to_cpu(sbi->s_es->s_last_orphan));
1146
1147         printk(KERN_ERR "sb_info orphan list:\n");
1148         list_for_each(l, &sbi->s_orphan) {
1149                 struct inode *inode = orphan_list_entry(l);
1150                 printk(KERN_ERR "  "
1151                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1152                        inode->i_sb->s_id, inode->i_ino, inode,
1153                        inode->i_mode, inode->i_nlink,
1154                        NEXT_ORPHAN(inode));
1155         }
1156 }
1157
1158 #ifdef CONFIG_QUOTA
1159 static int ext4_quota_off(struct super_block *sb, int type);
1160
1161 static inline void ext4_quota_off_umount(struct super_block *sb)
1162 {
1163         int type;
1164
1165         /* Use our quota_off function to clear inode flags etc. */
1166         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1167                 ext4_quota_off(sb, type);
1168 }
1169
1170 /*
1171  * This is a helper function which is used in the mount/remount
1172  * codepaths (which holds s_umount) to fetch the quota file name.
1173  */
1174 static inline char *get_qf_name(struct super_block *sb,
1175                                 struct ext4_sb_info *sbi,
1176                                 int type)
1177 {
1178         return rcu_dereference_protected(sbi->s_qf_names[type],
1179                                          lockdep_is_held(&sb->s_umount));
1180 }
1181 #else
1182 static inline void ext4_quota_off_umount(struct super_block *sb)
1183 {
1184 }
1185 #endif
1186
1187 static void ext4_put_super(struct super_block *sb)
1188 {
1189         struct ext4_sb_info *sbi = EXT4_SB(sb);
1190         struct ext4_super_block *es = sbi->s_es;
1191         struct buffer_head **group_desc;
1192         struct flex_groups **flex_groups;
1193         int aborted = 0;
1194         int i, err;
1195
1196         /*
1197          * Unregister sysfs before destroying jbd2 journal.
1198          * Since we could still access attr_journal_task attribute via sysfs
1199          * path which could have sbi->s_journal->j_task as NULL
1200          * Unregister sysfs before flush sbi->s_error_work.
1201          * Since user may read /proc/fs/ext4/xx/mb_groups during umount, If
1202          * read metadata verify failed then will queue error work.
1203          * flush_stashed_error_work will call start_this_handle may trigger
1204          * BUG_ON.
1205          */
1206         ext4_unregister_sysfs(sb);
1207
1208         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs unmount"))
1209                 ext4_msg(sb, KERN_INFO, "unmounting filesystem %pU.",
1210                          &sb->s_uuid);
1211
1212         ext4_unregister_li_request(sb);
1213         ext4_quota_off_umount(sb);
1214
1215         flush_work(&sbi->s_error_work);
1216         destroy_workqueue(sbi->rsv_conversion_wq);
1217         ext4_release_orphan_info(sb);
1218
1219         if (sbi->s_journal) {
1220                 aborted = is_journal_aborted(sbi->s_journal);
1221                 err = jbd2_journal_destroy(sbi->s_journal);
1222                 sbi->s_journal = NULL;
1223                 if ((err < 0) && !aborted) {
1224                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1225                 }
1226         }
1227
1228         ext4_es_unregister_shrinker(sbi);
1229         del_timer_sync(&sbi->s_err_report);
1230         ext4_release_system_zone(sb);
1231         ext4_mb_release(sb);
1232         ext4_ext_release(sb);
1233
1234         if (!sb_rdonly(sb) && !aborted) {
1235                 ext4_clear_feature_journal_needs_recovery(sb);
1236                 ext4_clear_feature_orphan_present(sb);
1237                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1238         }
1239         if (!sb_rdonly(sb))
1240                 ext4_commit_super(sb);
1241
1242         rcu_read_lock();
1243         group_desc = rcu_dereference(sbi->s_group_desc);
1244         for (i = 0; i < sbi->s_gdb_count; i++)
1245                 brelse(group_desc[i]);
1246         kvfree(group_desc);
1247         flex_groups = rcu_dereference(sbi->s_flex_groups);
1248         if (flex_groups) {
1249                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1250                         kvfree(flex_groups[i]);
1251                 kvfree(flex_groups);
1252         }
1253         rcu_read_unlock();
1254         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1255         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1256         percpu_counter_destroy(&sbi->s_dirs_counter);
1257         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1258         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1259         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1260 #ifdef CONFIG_QUOTA
1261         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1262                 kfree(get_qf_name(sb, sbi, i));
1263 #endif
1264
1265         /* Debugging code just in case the in-memory inode orphan list
1266          * isn't empty.  The on-disk one can be non-empty if we've
1267          * detected an error and taken the fs readonly, but the
1268          * in-memory list had better be clean by this point. */
1269         if (!list_empty(&sbi->s_orphan))
1270                 dump_orphan_list(sb, sbi);
1271         ASSERT(list_empty(&sbi->s_orphan));
1272
1273         sync_blockdev(sb->s_bdev);
1274         invalidate_bdev(sb->s_bdev);
1275         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1276                 /*
1277                  * Invalidate the journal device's buffers.  We don't want them
1278                  * floating about in memory - the physical journal device may
1279                  * hotswapped, and it breaks the `ro-after' testing code.
1280                  */
1281                 sync_blockdev(sbi->s_journal_bdev);
1282                 invalidate_bdev(sbi->s_journal_bdev);
1283                 ext4_blkdev_remove(sbi);
1284         }
1285
1286         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1287         sbi->s_ea_inode_cache = NULL;
1288
1289         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1290         sbi->s_ea_block_cache = NULL;
1291
1292         ext4_stop_mmpd(sbi);
1293
1294         brelse(sbi->s_sbh);
1295         sb->s_fs_info = NULL;
1296         /*
1297          * Now that we are completely done shutting down the
1298          * superblock, we need to actually destroy the kobject.
1299          */
1300         kobject_put(&sbi->s_kobj);
1301         wait_for_completion(&sbi->s_kobj_unregister);
1302         if (sbi->s_chksum_driver)
1303                 crypto_free_shash(sbi->s_chksum_driver);
1304         kfree(sbi->s_blockgroup_lock);
1305         fs_put_dax(sbi->s_daxdev, NULL);
1306         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1307 #if IS_ENABLED(CONFIG_UNICODE)
1308         utf8_unload(sb->s_encoding);
1309 #endif
1310         kfree(sbi);
1311 }
1312
1313 static struct kmem_cache *ext4_inode_cachep;
1314
1315 /*
1316  * Called inside transaction, so use GFP_NOFS
1317  */
1318 static struct inode *ext4_alloc_inode(struct super_block *sb)
1319 {
1320         struct ext4_inode_info *ei;
1321
1322         ei = alloc_inode_sb(sb, ext4_inode_cachep, GFP_NOFS);
1323         if (!ei)
1324                 return NULL;
1325
1326         inode_set_iversion(&ei->vfs_inode, 1);
1327         spin_lock_init(&ei->i_raw_lock);
1328         INIT_LIST_HEAD(&ei->i_prealloc_list);
1329         atomic_set(&ei->i_prealloc_active, 0);
1330         spin_lock_init(&ei->i_prealloc_lock);
1331         ext4_es_init_tree(&ei->i_es_tree);
1332         rwlock_init(&ei->i_es_lock);
1333         INIT_LIST_HEAD(&ei->i_es_list);
1334         ei->i_es_all_nr = 0;
1335         ei->i_es_shk_nr = 0;
1336         ei->i_es_shrink_lblk = 0;
1337         ei->i_reserved_data_blocks = 0;
1338         spin_lock_init(&(ei->i_block_reservation_lock));
1339         ext4_init_pending_tree(&ei->i_pending_tree);
1340 #ifdef CONFIG_QUOTA
1341         ei->i_reserved_quota = 0;
1342         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1343 #endif
1344         ei->jinode = NULL;
1345         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1346         spin_lock_init(&ei->i_completed_io_lock);
1347         ei->i_sync_tid = 0;
1348         ei->i_datasync_tid = 0;
1349         atomic_set(&ei->i_unwritten, 0);
1350         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1351         ext4_fc_init_inode(&ei->vfs_inode);
1352         mutex_init(&ei->i_fc_lock);
1353         return &ei->vfs_inode;
1354 }
1355
1356 static int ext4_drop_inode(struct inode *inode)
1357 {
1358         int drop = generic_drop_inode(inode);
1359
1360         if (!drop)
1361                 drop = fscrypt_drop_inode(inode);
1362
1363         trace_ext4_drop_inode(inode, drop);
1364         return drop;
1365 }
1366
1367 static void ext4_free_in_core_inode(struct inode *inode)
1368 {
1369         fscrypt_free_inode(inode);
1370         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1371                 pr_warn("%s: inode %ld still in fc list",
1372                         __func__, inode->i_ino);
1373         }
1374         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1375 }
1376
1377 static void ext4_destroy_inode(struct inode *inode)
1378 {
1379         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1380                 ext4_msg(inode->i_sb, KERN_ERR,
1381                          "Inode %lu (%p): orphan list check failed!",
1382                          inode->i_ino, EXT4_I(inode));
1383                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1384                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1385                                 true);
1386                 dump_stack();
1387         }
1388
1389         if (EXT4_I(inode)->i_reserved_data_blocks)
1390                 ext4_msg(inode->i_sb, KERN_ERR,
1391                          "Inode %lu (%p): i_reserved_data_blocks (%u) not cleared!",
1392                          inode->i_ino, EXT4_I(inode),
1393                          EXT4_I(inode)->i_reserved_data_blocks);
1394 }
1395
1396 static void init_once(void *foo)
1397 {
1398         struct ext4_inode_info *ei = foo;
1399
1400         INIT_LIST_HEAD(&ei->i_orphan);
1401         init_rwsem(&ei->xattr_sem);
1402         init_rwsem(&ei->i_data_sem);
1403         inode_init_once(&ei->vfs_inode);
1404         ext4_fc_init_inode(&ei->vfs_inode);
1405 }
1406
1407 static int __init init_inodecache(void)
1408 {
1409         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1410                                 sizeof(struct ext4_inode_info), 0,
1411                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1412                                         SLAB_ACCOUNT),
1413                                 offsetof(struct ext4_inode_info, i_data),
1414                                 sizeof_field(struct ext4_inode_info, i_data),
1415                                 init_once);
1416         if (ext4_inode_cachep == NULL)
1417                 return -ENOMEM;
1418         return 0;
1419 }
1420
1421 static void destroy_inodecache(void)
1422 {
1423         /*
1424          * Make sure all delayed rcu free inodes are flushed before we
1425          * destroy cache.
1426          */
1427         rcu_barrier();
1428         kmem_cache_destroy(ext4_inode_cachep);
1429 }
1430
1431 void ext4_clear_inode(struct inode *inode)
1432 {
1433         ext4_fc_del(inode);
1434         invalidate_inode_buffers(inode);
1435         clear_inode(inode);
1436         ext4_discard_preallocations(inode, 0);
1437         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1438         dquot_drop(inode);
1439         if (EXT4_I(inode)->jinode) {
1440                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1441                                                EXT4_I(inode)->jinode);
1442                 jbd2_free_inode(EXT4_I(inode)->jinode);
1443                 EXT4_I(inode)->jinode = NULL;
1444         }
1445         fscrypt_put_encryption_info(inode);
1446         fsverity_cleanup_inode(inode);
1447 }
1448
1449 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1450                                         u64 ino, u32 generation)
1451 {
1452         struct inode *inode;
1453
1454         /*
1455          * Currently we don't know the generation for parent directory, so
1456          * a generation of 0 means "accept any"
1457          */
1458         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1459         if (IS_ERR(inode))
1460                 return ERR_CAST(inode);
1461         if (generation && inode->i_generation != generation) {
1462                 iput(inode);
1463                 return ERR_PTR(-ESTALE);
1464         }
1465
1466         return inode;
1467 }
1468
1469 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1470                                         int fh_len, int fh_type)
1471 {
1472         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1473                                     ext4_nfs_get_inode);
1474 }
1475
1476 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1477                                         int fh_len, int fh_type)
1478 {
1479         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1480                                     ext4_nfs_get_inode);
1481 }
1482
1483 static int ext4_nfs_commit_metadata(struct inode *inode)
1484 {
1485         struct writeback_control wbc = {
1486                 .sync_mode = WB_SYNC_ALL
1487         };
1488
1489         trace_ext4_nfs_commit_metadata(inode);
1490         return ext4_write_inode(inode, &wbc);
1491 }
1492
1493 #ifdef CONFIG_QUOTA
1494 static const char * const quotatypes[] = INITQFNAMES;
1495 #define QTYPE2NAME(t) (quotatypes[t])
1496
1497 static int ext4_write_dquot(struct dquot *dquot);
1498 static int ext4_acquire_dquot(struct dquot *dquot);
1499 static int ext4_release_dquot(struct dquot *dquot);
1500 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1501 static int ext4_write_info(struct super_block *sb, int type);
1502 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1503                          const struct path *path);
1504 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1505                                size_t len, loff_t off);
1506 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1507                                 const char *data, size_t len, loff_t off);
1508 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1509                              unsigned int flags);
1510
1511 static struct dquot **ext4_get_dquots(struct inode *inode)
1512 {
1513         return EXT4_I(inode)->i_dquot;
1514 }
1515
1516 static const struct dquot_operations ext4_quota_operations = {
1517         .get_reserved_space     = ext4_get_reserved_space,
1518         .write_dquot            = ext4_write_dquot,
1519         .acquire_dquot          = ext4_acquire_dquot,
1520         .release_dquot          = ext4_release_dquot,
1521         .mark_dirty             = ext4_mark_dquot_dirty,
1522         .write_info             = ext4_write_info,
1523         .alloc_dquot            = dquot_alloc,
1524         .destroy_dquot          = dquot_destroy,
1525         .get_projid             = ext4_get_projid,
1526         .get_inode_usage        = ext4_get_inode_usage,
1527         .get_next_id            = dquot_get_next_id,
1528 };
1529
1530 static const struct quotactl_ops ext4_qctl_operations = {
1531         .quota_on       = ext4_quota_on,
1532         .quota_off      = ext4_quota_off,
1533         .quota_sync     = dquot_quota_sync,
1534         .get_state      = dquot_get_state,
1535         .set_info       = dquot_set_dqinfo,
1536         .get_dqblk      = dquot_get_dqblk,
1537         .set_dqblk      = dquot_set_dqblk,
1538         .get_nextdqblk  = dquot_get_next_dqblk,
1539 };
1540 #endif
1541
1542 static const struct super_operations ext4_sops = {
1543         .alloc_inode    = ext4_alloc_inode,
1544         .free_inode     = ext4_free_in_core_inode,
1545         .destroy_inode  = ext4_destroy_inode,
1546         .write_inode    = ext4_write_inode,
1547         .dirty_inode    = ext4_dirty_inode,
1548         .drop_inode     = ext4_drop_inode,
1549         .evict_inode    = ext4_evict_inode,
1550         .put_super      = ext4_put_super,
1551         .sync_fs        = ext4_sync_fs,
1552         .freeze_fs      = ext4_freeze,
1553         .unfreeze_fs    = ext4_unfreeze,
1554         .statfs         = ext4_statfs,
1555         .show_options   = ext4_show_options,
1556 #ifdef CONFIG_QUOTA
1557         .quota_read     = ext4_quota_read,
1558         .quota_write    = ext4_quota_write,
1559         .get_dquots     = ext4_get_dquots,
1560 #endif
1561 };
1562
1563 static const struct export_operations ext4_export_ops = {
1564         .fh_to_dentry = ext4_fh_to_dentry,
1565         .fh_to_parent = ext4_fh_to_parent,
1566         .get_parent = ext4_get_parent,
1567         .commit_metadata = ext4_nfs_commit_metadata,
1568 };
1569
1570 enum {
1571         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1572         Opt_resgid, Opt_resuid, Opt_sb,
1573         Opt_nouid32, Opt_debug, Opt_removed,
1574         Opt_user_xattr, Opt_acl,
1575         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1576         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1577         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1578         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1579         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1580         Opt_inlinecrypt,
1581         Opt_usrjquota, Opt_grpjquota, Opt_quota,
1582         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1583         Opt_usrquota, Opt_grpquota, Opt_prjquota,
1584         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1585         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1586         Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
1587         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1588         Opt_inode_readahead_blks, Opt_journal_ioprio,
1589         Opt_dioread_nolock, Opt_dioread_lock,
1590         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1591         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1592         Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1593         Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
1594 #ifdef CONFIG_EXT4_DEBUG
1595         Opt_fc_debug_max_replay, Opt_fc_debug_force
1596 #endif
1597 };
1598
1599 static const struct constant_table ext4_param_errors[] = {
1600         {"continue",    EXT4_MOUNT_ERRORS_CONT},
1601         {"panic",       EXT4_MOUNT_ERRORS_PANIC},
1602         {"remount-ro",  EXT4_MOUNT_ERRORS_RO},
1603         {}
1604 };
1605
1606 static const struct constant_table ext4_param_data[] = {
1607         {"journal",     EXT4_MOUNT_JOURNAL_DATA},
1608         {"ordered",     EXT4_MOUNT_ORDERED_DATA},
1609         {"writeback",   EXT4_MOUNT_WRITEBACK_DATA},
1610         {}
1611 };
1612
1613 static const struct constant_table ext4_param_data_err[] = {
1614         {"abort",       Opt_data_err_abort},
1615         {"ignore",      Opt_data_err_ignore},
1616         {}
1617 };
1618
1619 static const struct constant_table ext4_param_jqfmt[] = {
1620         {"vfsold",      QFMT_VFS_OLD},
1621         {"vfsv0",       QFMT_VFS_V0},
1622         {"vfsv1",       QFMT_VFS_V1},
1623         {}
1624 };
1625
1626 static const struct constant_table ext4_param_dax[] = {
1627         {"always",      Opt_dax_always},
1628         {"inode",       Opt_dax_inode},
1629         {"never",       Opt_dax_never},
1630         {}
1631 };
1632
1633 /* String parameter that allows empty argument */
1634 #define fsparam_string_empty(NAME, OPT) \
1635         __fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
1636
1637 /*
1638  * Mount option specification
1639  * We don't use fsparam_flag_no because of the way we set the
1640  * options and the way we show them in _ext4_show_options(). To
1641  * keep the changes to a minimum, let's keep the negative options
1642  * separate for now.
1643  */
1644 static const struct fs_parameter_spec ext4_param_specs[] = {
1645         fsparam_flag    ("bsddf",               Opt_bsd_df),
1646         fsparam_flag    ("minixdf",             Opt_minix_df),
1647         fsparam_flag    ("grpid",               Opt_grpid),
1648         fsparam_flag    ("bsdgroups",           Opt_grpid),
1649         fsparam_flag    ("nogrpid",             Opt_nogrpid),
1650         fsparam_flag    ("sysvgroups",          Opt_nogrpid),
1651         fsparam_u32     ("resgid",              Opt_resgid),
1652         fsparam_u32     ("resuid",              Opt_resuid),
1653         fsparam_u32     ("sb",                  Opt_sb),
1654         fsparam_enum    ("errors",              Opt_errors, ext4_param_errors),
1655         fsparam_flag    ("nouid32",             Opt_nouid32),
1656         fsparam_flag    ("debug",               Opt_debug),
1657         fsparam_flag    ("oldalloc",            Opt_removed),
1658         fsparam_flag    ("orlov",               Opt_removed),
1659         fsparam_flag    ("user_xattr",          Opt_user_xattr),
1660         fsparam_flag    ("acl",                 Opt_acl),
1661         fsparam_flag    ("norecovery",          Opt_noload),
1662         fsparam_flag    ("noload",              Opt_noload),
1663         fsparam_flag    ("bh",                  Opt_removed),
1664         fsparam_flag    ("nobh",                Opt_removed),
1665         fsparam_u32     ("commit",              Opt_commit),
1666         fsparam_u32     ("min_batch_time",      Opt_min_batch_time),
1667         fsparam_u32     ("max_batch_time",      Opt_max_batch_time),
1668         fsparam_u32     ("journal_dev",         Opt_journal_dev),
1669         fsparam_bdev    ("journal_path",        Opt_journal_path),
1670         fsparam_flag    ("journal_checksum",    Opt_journal_checksum),
1671         fsparam_flag    ("nojournal_checksum",  Opt_nojournal_checksum),
1672         fsparam_flag    ("journal_async_commit",Opt_journal_async_commit),
1673         fsparam_flag    ("abort",               Opt_abort),
1674         fsparam_enum    ("data",                Opt_data, ext4_param_data),
1675         fsparam_enum    ("data_err",            Opt_data_err,
1676                                                 ext4_param_data_err),
1677         fsparam_string_empty
1678                         ("usrjquota",           Opt_usrjquota),
1679         fsparam_string_empty
1680                         ("grpjquota",           Opt_grpjquota),
1681         fsparam_enum    ("jqfmt",               Opt_jqfmt, ext4_param_jqfmt),
1682         fsparam_flag    ("grpquota",            Opt_grpquota),
1683         fsparam_flag    ("quota",               Opt_quota),
1684         fsparam_flag    ("noquota",             Opt_noquota),
1685         fsparam_flag    ("usrquota",            Opt_usrquota),
1686         fsparam_flag    ("prjquota",            Opt_prjquota),
1687         fsparam_flag    ("barrier",             Opt_barrier),
1688         fsparam_u32     ("barrier",             Opt_barrier),
1689         fsparam_flag    ("nobarrier",           Opt_nobarrier),
1690         fsparam_flag    ("i_version",           Opt_removed),
1691         fsparam_flag    ("dax",                 Opt_dax),
1692         fsparam_enum    ("dax",                 Opt_dax_type, ext4_param_dax),
1693         fsparam_u32     ("stripe",              Opt_stripe),
1694         fsparam_flag    ("delalloc",            Opt_delalloc),
1695         fsparam_flag    ("nodelalloc",          Opt_nodelalloc),
1696         fsparam_flag    ("warn_on_error",       Opt_warn_on_error),
1697         fsparam_flag    ("nowarn_on_error",     Opt_nowarn_on_error),
1698         fsparam_u32     ("debug_want_extra_isize",
1699                                                 Opt_debug_want_extra_isize),
1700         fsparam_flag    ("mblk_io_submit",      Opt_removed),
1701         fsparam_flag    ("nomblk_io_submit",    Opt_removed),
1702         fsparam_flag    ("block_validity",      Opt_block_validity),
1703         fsparam_flag    ("noblock_validity",    Opt_noblock_validity),
1704         fsparam_u32     ("inode_readahead_blks",
1705                                                 Opt_inode_readahead_blks),
1706         fsparam_u32     ("journal_ioprio",      Opt_journal_ioprio),
1707         fsparam_u32     ("auto_da_alloc",       Opt_auto_da_alloc),
1708         fsparam_flag    ("auto_da_alloc",       Opt_auto_da_alloc),
1709         fsparam_flag    ("noauto_da_alloc",     Opt_noauto_da_alloc),
1710         fsparam_flag    ("dioread_nolock",      Opt_dioread_nolock),
1711         fsparam_flag    ("nodioread_nolock",    Opt_dioread_lock),
1712         fsparam_flag    ("dioread_lock",        Opt_dioread_lock),
1713         fsparam_flag    ("discard",             Opt_discard),
1714         fsparam_flag    ("nodiscard",           Opt_nodiscard),
1715         fsparam_u32     ("init_itable",         Opt_init_itable),
1716         fsparam_flag    ("init_itable",         Opt_init_itable),
1717         fsparam_flag    ("noinit_itable",       Opt_noinit_itable),
1718 #ifdef CONFIG_EXT4_DEBUG
1719         fsparam_flag    ("fc_debug_force",      Opt_fc_debug_force),
1720         fsparam_u32     ("fc_debug_max_replay", Opt_fc_debug_max_replay),
1721 #endif
1722         fsparam_u32     ("max_dir_size_kb",     Opt_max_dir_size_kb),
1723         fsparam_flag    ("test_dummy_encryption",
1724                                                 Opt_test_dummy_encryption),
1725         fsparam_string  ("test_dummy_encryption",
1726                                                 Opt_test_dummy_encryption),
1727         fsparam_flag    ("inlinecrypt",         Opt_inlinecrypt),
1728         fsparam_flag    ("nombcache",           Opt_nombcache),
1729         fsparam_flag    ("no_mbcache",          Opt_nombcache), /* for backward compatibility */
1730         fsparam_flag    ("prefetch_block_bitmaps",
1731                                                 Opt_removed),
1732         fsparam_flag    ("no_prefetch_block_bitmaps",
1733                                                 Opt_no_prefetch_block_bitmaps),
1734         fsparam_s32     ("mb_optimize_scan",    Opt_mb_optimize_scan),
1735         fsparam_string  ("check",               Opt_removed),   /* mount option from ext2/3 */
1736         fsparam_flag    ("nocheck",             Opt_removed),   /* mount option from ext2/3 */
1737         fsparam_flag    ("reservation",         Opt_removed),   /* mount option from ext2/3 */
1738         fsparam_flag    ("noreservation",       Opt_removed),   /* mount option from ext2/3 */
1739         fsparam_u32     ("journal",             Opt_removed),   /* mount option from ext2/3 */
1740         {}
1741 };
1742
1743 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1744
1745 #define MOPT_SET        0x0001
1746 #define MOPT_CLEAR      0x0002
1747 #define MOPT_NOSUPPORT  0x0004
1748 #define MOPT_EXPLICIT   0x0008
1749 #ifdef CONFIG_QUOTA
1750 #define MOPT_Q          0
1751 #define MOPT_QFMT       0x0010
1752 #else
1753 #define MOPT_Q          MOPT_NOSUPPORT
1754 #define MOPT_QFMT       MOPT_NOSUPPORT
1755 #endif
1756 #define MOPT_NO_EXT2    0x0020
1757 #define MOPT_NO_EXT3    0x0040
1758 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1759 #define MOPT_SKIP       0x0080
1760 #define MOPT_2          0x0100
1761
1762 static const struct mount_opts {
1763         int     token;
1764         int     mount_opt;
1765         int     flags;
1766 } ext4_mount_opts[] = {
1767         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1768         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1769         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1770         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1771         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1772         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1773         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1774          MOPT_EXT4_ONLY | MOPT_SET},
1775         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1776          MOPT_EXT4_ONLY | MOPT_CLEAR},
1777         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1778         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1779         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1780          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1781         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1782          MOPT_EXT4_ONLY | MOPT_CLEAR},
1783         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1784         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1785         {Opt_commit, 0, MOPT_NO_EXT2},
1786         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1787          MOPT_EXT4_ONLY | MOPT_CLEAR},
1788         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1789          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1790         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1791                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1792          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1793         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1794         {Opt_data_err, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_NO_EXT2},
1795         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1796         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1797         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1798         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1799         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1800         {Opt_dax_type, 0, MOPT_EXT4_ONLY},
1801         {Opt_journal_dev, 0, MOPT_NO_EXT2},
1802         {Opt_journal_path, 0, MOPT_NO_EXT2},
1803         {Opt_journal_ioprio, 0, MOPT_NO_EXT2},
1804         {Opt_data, 0, MOPT_NO_EXT2},
1805         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1806 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1807         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1808 #else
1809         {Opt_acl, 0, MOPT_NOSUPPORT},
1810 #endif
1811         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1812         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1813         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1814         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1815                                                         MOPT_SET | MOPT_Q},
1816         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1817                                                         MOPT_SET | MOPT_Q},
1818         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1819                                                         MOPT_SET | MOPT_Q},
1820         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1821                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1822                                                         MOPT_CLEAR | MOPT_Q},
1823         {Opt_usrjquota, 0, MOPT_Q},
1824         {Opt_grpjquota, 0, MOPT_Q},
1825         {Opt_jqfmt, 0, MOPT_QFMT},
1826         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1827         {Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
1828          MOPT_SET},
1829 #ifdef CONFIG_EXT4_DEBUG
1830         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1831          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1832 #endif
1833         {Opt_err, 0, 0}
1834 };
1835
1836 #if IS_ENABLED(CONFIG_UNICODE)
1837 static const struct ext4_sb_encodings {
1838         __u16 magic;
1839         char *name;
1840         unsigned int version;
1841 } ext4_sb_encoding_map[] = {
1842         {EXT4_ENC_UTF8_12_1, "utf8", UNICODE_AGE(12, 1, 0)},
1843 };
1844
1845 static const struct ext4_sb_encodings *
1846 ext4_sb_read_encoding(const struct ext4_super_block *es)
1847 {
1848         __u16 magic = le16_to_cpu(es->s_encoding);
1849         int i;
1850
1851         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1852                 if (magic == ext4_sb_encoding_map[i].magic)
1853                         return &ext4_sb_encoding_map[i];
1854
1855         return NULL;
1856 }
1857 #endif
1858
1859 #define EXT4_SPEC_JQUOTA                        (1 <<  0)
1860 #define EXT4_SPEC_JQFMT                         (1 <<  1)
1861 #define EXT4_SPEC_DATAJ                         (1 <<  2)
1862 #define EXT4_SPEC_SB_BLOCK                      (1 <<  3)
1863 #define EXT4_SPEC_JOURNAL_DEV                   (1 <<  4)
1864 #define EXT4_SPEC_JOURNAL_IOPRIO                (1 <<  5)
1865 #define EXT4_SPEC_s_want_extra_isize            (1 <<  7)
1866 #define EXT4_SPEC_s_max_batch_time              (1 <<  8)
1867 #define EXT4_SPEC_s_min_batch_time              (1 <<  9)
1868 #define EXT4_SPEC_s_inode_readahead_blks        (1 << 10)
1869 #define EXT4_SPEC_s_li_wait_mult                (1 << 11)
1870 #define EXT4_SPEC_s_max_dir_size_kb             (1 << 12)
1871 #define EXT4_SPEC_s_stripe                      (1 << 13)
1872 #define EXT4_SPEC_s_resuid                      (1 << 14)
1873 #define EXT4_SPEC_s_resgid                      (1 << 15)
1874 #define EXT4_SPEC_s_commit_interval             (1 << 16)
1875 #define EXT4_SPEC_s_fc_debug_max_replay         (1 << 17)
1876 #define EXT4_SPEC_s_sb_block                    (1 << 18)
1877 #define EXT4_SPEC_mb_optimize_scan              (1 << 19)
1878
1879 struct ext4_fs_context {
1880         char            *s_qf_names[EXT4_MAXQUOTAS];
1881         struct fscrypt_dummy_policy dummy_enc_policy;
1882         int             s_jquota_fmt;   /* Format of quota to use */
1883 #ifdef CONFIG_EXT4_DEBUG
1884         int s_fc_debug_max_replay;
1885 #endif
1886         unsigned short  qname_spec;
1887         unsigned long   vals_s_flags;   /* Bits to set in s_flags */
1888         unsigned long   mask_s_flags;   /* Bits changed in s_flags */
1889         unsigned long   journal_devnum;
1890         unsigned long   s_commit_interval;
1891         unsigned long   s_stripe;
1892         unsigned int    s_inode_readahead_blks;
1893         unsigned int    s_want_extra_isize;
1894         unsigned int    s_li_wait_mult;
1895         unsigned int    s_max_dir_size_kb;
1896         unsigned int    journal_ioprio;
1897         unsigned int    vals_s_mount_opt;
1898         unsigned int    mask_s_mount_opt;
1899         unsigned int    vals_s_mount_opt2;
1900         unsigned int    mask_s_mount_opt2;
1901         unsigned long   vals_s_mount_flags;
1902         unsigned long   mask_s_mount_flags;
1903         unsigned int    opt_flags;      /* MOPT flags */
1904         unsigned int    spec;
1905         u32             s_max_batch_time;
1906         u32             s_min_batch_time;
1907         kuid_t          s_resuid;
1908         kgid_t          s_resgid;
1909         ext4_fsblk_t    s_sb_block;
1910 };
1911
1912 static void ext4_fc_free(struct fs_context *fc)
1913 {
1914         struct ext4_fs_context *ctx = fc->fs_private;
1915         int i;
1916
1917         if (!ctx)
1918                 return;
1919
1920         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1921                 kfree(ctx->s_qf_names[i]);
1922
1923         fscrypt_free_dummy_policy(&ctx->dummy_enc_policy);
1924         kfree(ctx);
1925 }
1926
1927 int ext4_init_fs_context(struct fs_context *fc)
1928 {
1929         struct ext4_fs_context *ctx;
1930
1931         ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
1932         if (!ctx)
1933                 return -ENOMEM;
1934
1935         fc->fs_private = ctx;
1936         fc->ops = &ext4_context_ops;
1937
1938         return 0;
1939 }
1940
1941 #ifdef CONFIG_QUOTA
1942 /*
1943  * Note the name of the specified quota file.
1944  */
1945 static int note_qf_name(struct fs_context *fc, int qtype,
1946                        struct fs_parameter *param)
1947 {
1948         struct ext4_fs_context *ctx = fc->fs_private;
1949         char *qname;
1950
1951         if (param->size < 1) {
1952                 ext4_msg(NULL, KERN_ERR, "Missing quota name");
1953                 return -EINVAL;
1954         }
1955         if (strchr(param->string, '/')) {
1956                 ext4_msg(NULL, KERN_ERR,
1957                          "quotafile must be on filesystem root");
1958                 return -EINVAL;
1959         }
1960         if (ctx->s_qf_names[qtype]) {
1961                 if (strcmp(ctx->s_qf_names[qtype], param->string) != 0) {
1962                         ext4_msg(NULL, KERN_ERR,
1963                                  "%s quota file already specified",
1964                                  QTYPE2NAME(qtype));
1965                         return -EINVAL;
1966                 }
1967                 return 0;
1968         }
1969
1970         qname = kmemdup_nul(param->string, param->size, GFP_KERNEL);
1971         if (!qname) {
1972                 ext4_msg(NULL, KERN_ERR,
1973                          "Not enough memory for storing quotafile name");
1974                 return -ENOMEM;
1975         }
1976         ctx->s_qf_names[qtype] = qname;
1977         ctx->qname_spec |= 1 << qtype;
1978         ctx->spec |= EXT4_SPEC_JQUOTA;
1979         return 0;
1980 }
1981
1982 /*
1983  * Clear the name of the specified quota file.
1984  */
1985 static int unnote_qf_name(struct fs_context *fc, int qtype)
1986 {
1987         struct ext4_fs_context *ctx = fc->fs_private;
1988
1989         if (ctx->s_qf_names[qtype])
1990                 kfree(ctx->s_qf_names[qtype]);
1991
1992         ctx->s_qf_names[qtype] = NULL;
1993         ctx->qname_spec |= 1 << qtype;
1994         ctx->spec |= EXT4_SPEC_JQUOTA;
1995         return 0;
1996 }
1997 #endif
1998
1999 static int ext4_parse_test_dummy_encryption(const struct fs_parameter *param,
2000                                             struct ext4_fs_context *ctx)
2001 {
2002         int err;
2003
2004         if (!IS_ENABLED(CONFIG_FS_ENCRYPTION)) {
2005                 ext4_msg(NULL, KERN_WARNING,
2006                          "test_dummy_encryption option not supported");
2007                 return -EINVAL;
2008         }
2009         err = fscrypt_parse_test_dummy_encryption(param,
2010                                                   &ctx->dummy_enc_policy);
2011         if (err == -EINVAL) {
2012                 ext4_msg(NULL, KERN_WARNING,
2013                          "Value of option \"%s\" is unrecognized", param->key);
2014         } else if (err == -EEXIST) {
2015                 ext4_msg(NULL, KERN_WARNING,
2016                          "Conflicting test_dummy_encryption options");
2017                 return -EINVAL;
2018         }
2019         return err;
2020 }
2021
2022 #define EXT4_SET_CTX(name)                                              \
2023 static inline void ctx_set_##name(struct ext4_fs_context *ctx,          \
2024                                   unsigned long flag)                   \
2025 {                                                                       \
2026         ctx->mask_s_##name |= flag;                                     \
2027         ctx->vals_s_##name |= flag;                                     \
2028 }
2029
2030 #define EXT4_CLEAR_CTX(name)                                            \
2031 static inline void ctx_clear_##name(struct ext4_fs_context *ctx,        \
2032                                     unsigned long flag)                 \
2033 {                                                                       \
2034         ctx->mask_s_##name |= flag;                                     \
2035         ctx->vals_s_##name &= ~flag;                                    \
2036 }
2037
2038 #define EXT4_TEST_CTX(name)                                             \
2039 static inline unsigned long                                             \
2040 ctx_test_##name(struct ext4_fs_context *ctx, unsigned long flag)        \
2041 {                                                                       \
2042         return (ctx->vals_s_##name & flag);                             \
2043 }
2044
2045 EXT4_SET_CTX(flags); /* set only */
2046 EXT4_SET_CTX(mount_opt);
2047 EXT4_CLEAR_CTX(mount_opt);
2048 EXT4_TEST_CTX(mount_opt);
2049 EXT4_SET_CTX(mount_opt2);
2050 EXT4_CLEAR_CTX(mount_opt2);
2051 EXT4_TEST_CTX(mount_opt2);
2052
2053 static inline void ctx_set_mount_flag(struct ext4_fs_context *ctx, int bit)
2054 {
2055         set_bit(bit, &ctx->mask_s_mount_flags);
2056         set_bit(bit, &ctx->vals_s_mount_flags);
2057 }
2058
2059 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
2060 {
2061         struct ext4_fs_context *ctx = fc->fs_private;
2062         struct fs_parse_result result;
2063         const struct mount_opts *m;
2064         int is_remount;
2065         kuid_t uid;
2066         kgid_t gid;
2067         int token;
2068
2069         token = fs_parse(fc, ext4_param_specs, param, &result);
2070         if (token < 0)
2071                 return token;
2072         is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2073
2074         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2075                 if (token == m->token)
2076                         break;
2077
2078         ctx->opt_flags |= m->flags;
2079
2080         if (m->flags & MOPT_EXPLICIT) {
2081                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2082                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_EXPLICIT_DELALLOC);
2083                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2084                         ctx_set_mount_opt2(ctx,
2085                                        EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM);
2086                 } else
2087                         return -EINVAL;
2088         }
2089
2090         if (m->flags & MOPT_NOSUPPORT) {
2091                 ext4_msg(NULL, KERN_ERR, "%s option not supported",
2092                          param->key);
2093                 return 0;
2094         }
2095
2096         switch (token) {
2097 #ifdef CONFIG_QUOTA
2098         case Opt_usrjquota:
2099                 if (!*param->string)
2100                         return unnote_qf_name(fc, USRQUOTA);
2101                 else
2102                         return note_qf_name(fc, USRQUOTA, param);
2103         case Opt_grpjquota:
2104                 if (!*param->string)
2105                         return unnote_qf_name(fc, GRPQUOTA);
2106                 else
2107                         return note_qf_name(fc, GRPQUOTA, param);
2108 #endif
2109         case Opt_sb:
2110                 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2111                         ext4_msg(NULL, KERN_WARNING,
2112                                  "Ignoring %s option on remount", param->key);
2113                 } else {
2114                         ctx->s_sb_block = result.uint_32;
2115                         ctx->spec |= EXT4_SPEC_s_sb_block;
2116                 }
2117                 return 0;
2118         case Opt_removed:
2119                 ext4_msg(NULL, KERN_WARNING, "Ignoring removed %s option",
2120                          param->key);
2121                 return 0;
2122         case Opt_abort:
2123                 ctx_set_mount_flag(ctx, EXT4_MF_FS_ABORTED);
2124                 return 0;
2125         case Opt_inlinecrypt:
2126 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2127                 ctx_set_flags(ctx, SB_INLINECRYPT);
2128 #else
2129                 ext4_msg(NULL, KERN_ERR, "inline encryption not supported");
2130 #endif
2131                 return 0;
2132         case Opt_errors:
2133                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_ERRORS_MASK);
2134                 ctx_set_mount_opt(ctx, result.uint_32);
2135                 return 0;
2136 #ifdef CONFIG_QUOTA
2137         case Opt_jqfmt:
2138                 ctx->s_jquota_fmt = result.uint_32;
2139                 ctx->spec |= EXT4_SPEC_JQFMT;
2140                 return 0;
2141 #endif
2142         case Opt_data:
2143                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2144                 ctx_set_mount_opt(ctx, result.uint_32);
2145                 ctx->spec |= EXT4_SPEC_DATAJ;
2146                 return 0;
2147         case Opt_commit:
2148                 if (result.uint_32 == 0)
2149                         ctx->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE;
2150                 else if (result.uint_32 > INT_MAX / HZ) {
2151                         ext4_msg(NULL, KERN_ERR,
2152                                  "Invalid commit interval %d, "
2153                                  "must be smaller than %d",
2154                                  result.uint_32, INT_MAX / HZ);
2155                         return -EINVAL;
2156                 }
2157                 ctx->s_commit_interval = HZ * result.uint_32;
2158                 ctx->spec |= EXT4_SPEC_s_commit_interval;
2159                 return 0;
2160         case Opt_debug_want_extra_isize:
2161                 if ((result.uint_32 & 1) || (result.uint_32 < 4)) {
2162                         ext4_msg(NULL, KERN_ERR,
2163                                  "Invalid want_extra_isize %d", result.uint_32);
2164                         return -EINVAL;
2165                 }
2166                 ctx->s_want_extra_isize = result.uint_32;
2167                 ctx->spec |= EXT4_SPEC_s_want_extra_isize;
2168                 return 0;
2169         case Opt_max_batch_time:
2170                 ctx->s_max_batch_time = result.uint_32;
2171                 ctx->spec |= EXT4_SPEC_s_max_batch_time;
2172                 return 0;
2173         case Opt_min_batch_time:
2174                 ctx->s_min_batch_time = result.uint_32;
2175                 ctx->spec |= EXT4_SPEC_s_min_batch_time;
2176                 return 0;
2177         case Opt_inode_readahead_blks:
2178                 if (result.uint_32 &&
2179                     (result.uint_32 > (1 << 30) ||
2180                      !is_power_of_2(result.uint_32))) {
2181                         ext4_msg(NULL, KERN_ERR,
2182                                  "EXT4-fs: inode_readahead_blks must be "
2183                                  "0 or a power of 2 smaller than 2^31");
2184                         return -EINVAL;
2185                 }
2186                 ctx->s_inode_readahead_blks = result.uint_32;
2187                 ctx->spec |= EXT4_SPEC_s_inode_readahead_blks;
2188                 return 0;
2189         case Opt_init_itable:
2190                 ctx_set_mount_opt(ctx, EXT4_MOUNT_INIT_INODE_TABLE);
2191                 ctx->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
2192                 if (param->type == fs_value_is_string)
2193                         ctx->s_li_wait_mult = result.uint_32;
2194                 ctx->spec |= EXT4_SPEC_s_li_wait_mult;
2195                 return 0;
2196         case Opt_max_dir_size_kb:
2197                 ctx->s_max_dir_size_kb = result.uint_32;
2198                 ctx->spec |= EXT4_SPEC_s_max_dir_size_kb;
2199                 return 0;
2200 #ifdef CONFIG_EXT4_DEBUG
2201         case Opt_fc_debug_max_replay:
2202                 ctx->s_fc_debug_max_replay = result.uint_32;
2203                 ctx->spec |= EXT4_SPEC_s_fc_debug_max_replay;
2204                 return 0;
2205 #endif
2206         case Opt_stripe:
2207                 ctx->s_stripe = result.uint_32;
2208                 ctx->spec |= EXT4_SPEC_s_stripe;
2209                 return 0;
2210         case Opt_resuid:
2211                 uid = make_kuid(current_user_ns(), result.uint_32);
2212                 if (!uid_valid(uid)) {
2213                         ext4_msg(NULL, KERN_ERR, "Invalid uid value %d",
2214                                  result.uint_32);
2215                         return -EINVAL;
2216                 }
2217                 ctx->s_resuid = uid;
2218                 ctx->spec |= EXT4_SPEC_s_resuid;
2219                 return 0;
2220         case Opt_resgid:
2221                 gid = make_kgid(current_user_ns(), result.uint_32);
2222                 if (!gid_valid(gid)) {
2223                         ext4_msg(NULL, KERN_ERR, "Invalid gid value %d",
2224                                  result.uint_32);
2225                         return -EINVAL;
2226                 }
2227                 ctx->s_resgid = gid;
2228                 ctx->spec |= EXT4_SPEC_s_resgid;
2229                 return 0;
2230         case Opt_journal_dev:
2231                 if (is_remount) {
2232                         ext4_msg(NULL, KERN_ERR,
2233                                  "Cannot specify journal on remount");
2234                         return -EINVAL;
2235                 }
2236                 ctx->journal_devnum = result.uint_32;
2237                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2238                 return 0;
2239         case Opt_journal_path:
2240         {
2241                 struct inode *journal_inode;
2242                 struct path path;
2243                 int error;
2244
2245                 if (is_remount) {
2246                         ext4_msg(NULL, KERN_ERR,
2247                                  "Cannot specify journal on remount");
2248                         return -EINVAL;
2249                 }
2250
2251                 error = fs_lookup_param(fc, param, 1, LOOKUP_FOLLOW, &path);
2252                 if (error) {
2253                         ext4_msg(NULL, KERN_ERR, "error: could not find "
2254                                  "journal device path");
2255                         return -EINVAL;
2256                 }
2257
2258                 journal_inode = d_inode(path.dentry);
2259                 ctx->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2260                 ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2261                 path_put(&path);
2262                 return 0;
2263         }
2264         case Opt_journal_ioprio:
2265                 if (result.uint_32 > 7) {
2266                         ext4_msg(NULL, KERN_ERR, "Invalid journal IO priority"
2267                                  " (must be 0-7)");
2268                         return -EINVAL;
2269                 }
2270                 ctx->journal_ioprio =
2271                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, result.uint_32);
2272                 ctx->spec |= EXT4_SPEC_JOURNAL_IOPRIO;
2273                 return 0;
2274         case Opt_test_dummy_encryption:
2275                 return ext4_parse_test_dummy_encryption(param, ctx);
2276         case Opt_dax:
2277         case Opt_dax_type:
2278 #ifdef CONFIG_FS_DAX
2279         {
2280                 int type = (token == Opt_dax) ?
2281                            Opt_dax : result.uint_32;
2282
2283                 switch (type) {
2284                 case Opt_dax:
2285                 case Opt_dax_always:
2286                         ctx_set_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2287                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2288                         break;
2289                 case Opt_dax_never:
2290                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2291                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2292                         break;
2293                 case Opt_dax_inode:
2294                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2295                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2296                         /* Strictly for printing options */
2297                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE);
2298                         break;
2299                 }
2300                 return 0;
2301         }
2302 #else
2303                 ext4_msg(NULL, KERN_INFO, "dax option not supported");
2304                 return -EINVAL;
2305 #endif
2306         case Opt_data_err:
2307                 if (result.uint_32 == Opt_data_err_abort)
2308                         ctx_set_mount_opt(ctx, m->mount_opt);
2309                 else if (result.uint_32 == Opt_data_err_ignore)
2310                         ctx_clear_mount_opt(ctx, m->mount_opt);
2311                 return 0;
2312         case Opt_mb_optimize_scan:
2313                 if (result.int_32 == 1) {
2314                         ctx_set_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2315                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2316                 } else if (result.int_32 == 0) {
2317                         ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2318                         ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2319                 } else {
2320                         ext4_msg(NULL, KERN_WARNING,
2321                                  "mb_optimize_scan should be set to 0 or 1.");
2322                         return -EINVAL;
2323                 }
2324                 return 0;
2325         }
2326
2327         /*
2328          * At this point we should only be getting options requiring MOPT_SET,
2329          * or MOPT_CLEAR. Anything else is a bug
2330          */
2331         if (m->token == Opt_err) {
2332                 ext4_msg(NULL, KERN_WARNING, "buggy handling of option %s",
2333                          param->key);
2334                 WARN_ON(1);
2335                 return -EINVAL;
2336         }
2337
2338         else {
2339                 unsigned int set = 0;
2340
2341                 if ((param->type == fs_value_is_flag) ||
2342                     result.uint_32 > 0)
2343                         set = 1;
2344
2345                 if (m->flags & MOPT_CLEAR)
2346                         set = !set;
2347                 else if (unlikely(!(m->flags & MOPT_SET))) {
2348                         ext4_msg(NULL, KERN_WARNING,
2349                                  "buggy handling of option %s",
2350                                  param->key);
2351                         WARN_ON(1);
2352                         return -EINVAL;
2353                 }
2354                 if (m->flags & MOPT_2) {
2355                         if (set != 0)
2356                                 ctx_set_mount_opt2(ctx, m->mount_opt);
2357                         else
2358                                 ctx_clear_mount_opt2(ctx, m->mount_opt);
2359                 } else {
2360                         if (set != 0)
2361                                 ctx_set_mount_opt(ctx, m->mount_opt);
2362                         else
2363                                 ctx_clear_mount_opt(ctx, m->mount_opt);
2364                 }
2365         }
2366
2367         return 0;
2368 }
2369
2370 static int parse_options(struct fs_context *fc, char *options)
2371 {
2372         struct fs_parameter param;
2373         int ret;
2374         char *key;
2375
2376         if (!options)
2377                 return 0;
2378
2379         while ((key = strsep(&options, ",")) != NULL) {
2380                 if (*key) {
2381                         size_t v_len = 0;
2382                         char *value = strchr(key, '=');
2383
2384                         param.type = fs_value_is_flag;
2385                         param.string = NULL;
2386
2387                         if (value) {
2388                                 if (value == key)
2389                                         continue;
2390
2391                                 *value++ = 0;
2392                                 v_len = strlen(value);
2393                                 param.string = kmemdup_nul(value, v_len,
2394                                                            GFP_KERNEL);
2395                                 if (!param.string)
2396                                         return -ENOMEM;
2397                                 param.type = fs_value_is_string;
2398                         }
2399
2400                         param.key = key;
2401                         param.size = v_len;
2402
2403                         ret = ext4_parse_param(fc, &param);
2404                         if (param.string)
2405                                 kfree(param.string);
2406                         if (ret < 0)
2407                                 return ret;
2408                 }
2409         }
2410
2411         ret = ext4_validate_options(fc);
2412         if (ret < 0)
2413                 return ret;
2414
2415         return 0;
2416 }
2417
2418 static int parse_apply_sb_mount_options(struct super_block *sb,
2419                                         struct ext4_fs_context *m_ctx)
2420 {
2421         struct ext4_sb_info *sbi = EXT4_SB(sb);
2422         char *s_mount_opts = NULL;
2423         struct ext4_fs_context *s_ctx = NULL;
2424         struct fs_context *fc = NULL;
2425         int ret = -ENOMEM;
2426
2427         if (!sbi->s_es->s_mount_opts[0])
2428                 return 0;
2429
2430         s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
2431                                 sizeof(sbi->s_es->s_mount_opts),
2432                                 GFP_KERNEL);
2433         if (!s_mount_opts)
2434                 return ret;
2435
2436         fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
2437         if (!fc)
2438                 goto out_free;
2439
2440         s_ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2441         if (!s_ctx)
2442                 goto out_free;
2443
2444         fc->fs_private = s_ctx;
2445         fc->s_fs_info = sbi;
2446
2447         ret = parse_options(fc, s_mount_opts);
2448         if (ret < 0)
2449                 goto parse_failed;
2450
2451         ret = ext4_check_opt_consistency(fc, sb);
2452         if (ret < 0) {
2453 parse_failed:
2454                 ext4_msg(sb, KERN_WARNING,
2455                          "failed to parse options in superblock: %s",
2456                          s_mount_opts);
2457                 ret = 0;
2458                 goto out_free;
2459         }
2460
2461         if (s_ctx->spec & EXT4_SPEC_JOURNAL_DEV)
2462                 m_ctx->journal_devnum = s_ctx->journal_devnum;
2463         if (s_ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)
2464                 m_ctx->journal_ioprio = s_ctx->journal_ioprio;
2465
2466         ext4_apply_options(fc, sb);
2467         ret = 0;
2468
2469 out_free:
2470         if (fc) {
2471                 ext4_fc_free(fc);
2472                 kfree(fc);
2473         }
2474         kfree(s_mount_opts);
2475         return ret;
2476 }
2477
2478 static void ext4_apply_quota_options(struct fs_context *fc,
2479                                      struct super_block *sb)
2480 {
2481 #ifdef CONFIG_QUOTA
2482         bool quota_feature = ext4_has_feature_quota(sb);
2483         struct ext4_fs_context *ctx = fc->fs_private;
2484         struct ext4_sb_info *sbi = EXT4_SB(sb);
2485         char *qname;
2486         int i;
2487
2488         if (quota_feature)
2489                 return;
2490
2491         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2492                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2493                         if (!(ctx->qname_spec & (1 << i)))
2494                                 continue;
2495
2496                         qname = ctx->s_qf_names[i]; /* May be NULL */
2497                         if (qname)
2498                                 set_opt(sb, QUOTA);
2499                         ctx->s_qf_names[i] = NULL;
2500                         qname = rcu_replace_pointer(sbi->s_qf_names[i], qname,
2501                                                 lockdep_is_held(&sb->s_umount));
2502                         if (qname)
2503                                 kfree_rcu(qname);
2504                 }
2505         }
2506
2507         if (ctx->spec & EXT4_SPEC_JQFMT)
2508                 sbi->s_jquota_fmt = ctx->s_jquota_fmt;
2509 #endif
2510 }
2511
2512 /*
2513  * Check quota settings consistency.
2514  */
2515 static int ext4_check_quota_consistency(struct fs_context *fc,
2516                                         struct super_block *sb)
2517 {
2518 #ifdef CONFIG_QUOTA
2519         struct ext4_fs_context *ctx = fc->fs_private;
2520         struct ext4_sb_info *sbi = EXT4_SB(sb);
2521         bool quota_feature = ext4_has_feature_quota(sb);
2522         bool quota_loaded = sb_any_quota_loaded(sb);
2523         bool usr_qf_name, grp_qf_name, usrquota, grpquota;
2524         int quota_flags, i;
2525
2526         /*
2527          * We do the test below only for project quotas. 'usrquota' and
2528          * 'grpquota' mount options are allowed even without quota feature
2529          * to support legacy quotas in quota files.
2530          */
2531         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_PRJQUOTA) &&
2532             !ext4_has_feature_project(sb)) {
2533                 ext4_msg(NULL, KERN_ERR, "Project quota feature not enabled. "
2534                          "Cannot enable project quota enforcement.");
2535                 return -EINVAL;
2536         }
2537
2538         quota_flags = EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2539                       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA;
2540         if (quota_loaded &&
2541             ctx->mask_s_mount_opt & quota_flags &&
2542             !ctx_test_mount_opt(ctx, quota_flags))
2543                 goto err_quota_change;
2544
2545         if (ctx->spec & EXT4_SPEC_JQUOTA) {
2546
2547                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2548                         if (!(ctx->qname_spec & (1 << i)))
2549                                 continue;
2550
2551                         if (quota_loaded &&
2552                             !!sbi->s_qf_names[i] != !!ctx->s_qf_names[i])
2553                                 goto err_jquota_change;
2554
2555                         if (sbi->s_qf_names[i] && ctx->s_qf_names[i] &&
2556                             strcmp(get_qf_name(sb, sbi, i),
2557                                    ctx->s_qf_names[i]) != 0)
2558                                 goto err_jquota_specified;
2559                 }
2560
2561                 if (quota_feature) {
2562                         ext4_msg(NULL, KERN_INFO,
2563                                  "Journaled quota options ignored when "
2564                                  "QUOTA feature is enabled");
2565                         return 0;
2566                 }
2567         }
2568
2569         if (ctx->spec & EXT4_SPEC_JQFMT) {
2570                 if (sbi->s_jquota_fmt != ctx->s_jquota_fmt && quota_loaded)
2571                         goto err_jquota_change;
2572                 if (quota_feature) {
2573                         ext4_msg(NULL, KERN_INFO, "Quota format mount options "
2574                                  "ignored when QUOTA feature is enabled");
2575                         return 0;
2576                 }
2577         }
2578
2579         /* Make sure we don't mix old and new quota format */
2580         usr_qf_name = (get_qf_name(sb, sbi, USRQUOTA) ||
2581                        ctx->s_qf_names[USRQUOTA]);
2582         grp_qf_name = (get_qf_name(sb, sbi, GRPQUOTA) ||
2583                        ctx->s_qf_names[GRPQUOTA]);
2584
2585         usrquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2586                     test_opt(sb, USRQUOTA));
2587
2588         grpquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) ||
2589                     test_opt(sb, GRPQUOTA));
2590
2591         if (usr_qf_name) {
2592                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2593                 usrquota = false;
2594         }
2595         if (grp_qf_name) {
2596                 ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2597                 grpquota = false;
2598         }
2599
2600         if (usr_qf_name || grp_qf_name) {
2601                 if (usrquota || grpquota) {
2602                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2603                                  "format mixing");
2604                         return -EINVAL;
2605                 }
2606
2607                 if (!(ctx->spec & EXT4_SPEC_JQFMT || sbi->s_jquota_fmt)) {
2608                         ext4_msg(NULL, KERN_ERR, "journaled quota format "
2609                                  "not specified");
2610                         return -EINVAL;
2611                 }
2612         }
2613
2614         return 0;
2615
2616 err_quota_change:
2617         ext4_msg(NULL, KERN_ERR,
2618                  "Cannot change quota options when quota turned on");
2619         return -EINVAL;
2620 err_jquota_change:
2621         ext4_msg(NULL, KERN_ERR, "Cannot change journaled quota "
2622                  "options when quota turned on");
2623         return -EINVAL;
2624 err_jquota_specified:
2625         ext4_msg(NULL, KERN_ERR, "%s quota file already specified",
2626                  QTYPE2NAME(i));
2627         return -EINVAL;
2628 #else
2629         return 0;
2630 #endif
2631 }
2632
2633 static int ext4_check_test_dummy_encryption(const struct fs_context *fc,
2634                                             struct super_block *sb)
2635 {
2636         const struct ext4_fs_context *ctx = fc->fs_private;
2637         const struct ext4_sb_info *sbi = EXT4_SB(sb);
2638         int err;
2639
2640         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy))
2641                 return 0;
2642
2643         if (!ext4_has_feature_encrypt(sb)) {
2644                 ext4_msg(NULL, KERN_WARNING,
2645                          "test_dummy_encryption requires encrypt feature");
2646                 return -EINVAL;
2647         }
2648         /*
2649          * This mount option is just for testing, and it's not worthwhile to
2650          * implement the extra complexity (e.g. RCU protection) that would be
2651          * needed to allow it to be set or changed during remount.  We do allow
2652          * it to be specified during remount, but only if there is no change.
2653          */
2654         if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2655                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2656                                                  &ctx->dummy_enc_policy))
2657                         return 0;
2658                 ext4_msg(NULL, KERN_WARNING,
2659                          "Can't set or change test_dummy_encryption on remount");
2660                 return -EINVAL;
2661         }
2662         /* Also make sure s_mount_opts didn't contain a conflicting value. */
2663         if (fscrypt_is_dummy_policy_set(&sbi->s_dummy_enc_policy)) {
2664                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2665                                                  &ctx->dummy_enc_policy))
2666                         return 0;
2667                 ext4_msg(NULL, KERN_WARNING,
2668                          "Conflicting test_dummy_encryption options");
2669                 return -EINVAL;
2670         }
2671         /*
2672          * fscrypt_add_test_dummy_key() technically changes the super_block, so
2673          * technically it should be delayed until ext4_apply_options() like the
2674          * other changes.  But since we never get here for remounts (see above),
2675          * and this is the last chance to report errors, we do it here.
2676          */
2677         err = fscrypt_add_test_dummy_key(sb, &ctx->dummy_enc_policy);
2678         if (err)
2679                 ext4_msg(NULL, KERN_WARNING,
2680                          "Error adding test dummy encryption key [%d]", err);
2681         return err;
2682 }
2683
2684 static void ext4_apply_test_dummy_encryption(struct ext4_fs_context *ctx,
2685                                              struct super_block *sb)
2686 {
2687         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy) ||
2688             /* if already set, it was already verified to be the same */
2689             fscrypt_is_dummy_policy_set(&EXT4_SB(sb)->s_dummy_enc_policy))
2690                 return;
2691         EXT4_SB(sb)->s_dummy_enc_policy = ctx->dummy_enc_policy;
2692         memset(&ctx->dummy_enc_policy, 0, sizeof(ctx->dummy_enc_policy));
2693         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2694 }
2695
2696 static int ext4_check_opt_consistency(struct fs_context *fc,
2697                                       struct super_block *sb)
2698 {
2699         struct ext4_fs_context *ctx = fc->fs_private;
2700         struct ext4_sb_info *sbi = fc->s_fs_info;
2701         int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2702         int err;
2703
2704         if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2705                 ext4_msg(NULL, KERN_ERR,
2706                          "Mount option(s) incompatible with ext2");
2707                 return -EINVAL;
2708         }
2709         if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2710                 ext4_msg(NULL, KERN_ERR,
2711                          "Mount option(s) incompatible with ext3");
2712                 return -EINVAL;
2713         }
2714
2715         if (ctx->s_want_extra_isize >
2716             (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2717                 ext4_msg(NULL, KERN_ERR,
2718                          "Invalid want_extra_isize %d",
2719                          ctx->s_want_extra_isize);
2720                 return -EINVAL;
2721         }
2722
2723         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DIOREAD_NOLOCK)) {
2724                 int blocksize =
2725                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2726                 if (blocksize < PAGE_SIZE)
2727                         ext4_msg(NULL, KERN_WARNING, "Warning: mounting with an "
2728                                  "experimental mount option 'dioread_nolock' "
2729                                  "for blocksize < PAGE_SIZE");
2730         }
2731
2732         err = ext4_check_test_dummy_encryption(fc, sb);
2733         if (err)
2734                 return err;
2735
2736         if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2737                 if (!sbi->s_journal) {
2738                         ext4_msg(NULL, KERN_WARNING,
2739                                  "Remounting file system with no journal "
2740                                  "so ignoring journalled data option");
2741                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2742                 } else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2743                            test_opt(sb, DATA_FLAGS)) {
2744                         ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2745                                  "on remount");
2746                         return -EINVAL;
2747                 }
2748         }
2749
2750         if (is_remount) {
2751                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2752                     (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2753                         ext4_msg(NULL, KERN_ERR, "can't mount with "
2754                                  "both data=journal and dax");
2755                         return -EINVAL;
2756                 }
2757
2758                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2759                     (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2760                      (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2761 fail_dax_change_remount:
2762                         ext4_msg(NULL, KERN_ERR, "can't change "
2763                                  "dax mount option while remounting");
2764                         return -EINVAL;
2765                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2766                          (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2767                           (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2768                         goto fail_dax_change_remount;
2769                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2770                            ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2771                             (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2772                             !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2773                         goto fail_dax_change_remount;
2774                 }
2775         }
2776
2777         return ext4_check_quota_consistency(fc, sb);
2778 }
2779
2780 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2781 {
2782         struct ext4_fs_context *ctx = fc->fs_private;
2783         struct ext4_sb_info *sbi = fc->s_fs_info;
2784
2785         sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2786         sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2787         sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2788         sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2789         sbi->s_mount_flags &= ~ctx->mask_s_mount_flags;
2790         sbi->s_mount_flags |= ctx->vals_s_mount_flags;
2791         sb->s_flags &= ~ctx->mask_s_flags;
2792         sb->s_flags |= ctx->vals_s_flags;
2793
2794 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2795         APPLY(s_commit_interval);
2796         APPLY(s_stripe);
2797         APPLY(s_max_batch_time);
2798         APPLY(s_min_batch_time);
2799         APPLY(s_want_extra_isize);
2800         APPLY(s_inode_readahead_blks);
2801         APPLY(s_max_dir_size_kb);
2802         APPLY(s_li_wait_mult);
2803         APPLY(s_resgid);
2804         APPLY(s_resuid);
2805
2806 #ifdef CONFIG_EXT4_DEBUG
2807         APPLY(s_fc_debug_max_replay);
2808 #endif
2809
2810         ext4_apply_quota_options(fc, sb);
2811         ext4_apply_test_dummy_encryption(ctx, sb);
2812 }
2813
2814
2815 static int ext4_validate_options(struct fs_context *fc)
2816 {
2817 #ifdef CONFIG_QUOTA
2818         struct ext4_fs_context *ctx = fc->fs_private;
2819         char *usr_qf_name, *grp_qf_name;
2820
2821         usr_qf_name = ctx->s_qf_names[USRQUOTA];
2822         grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2823
2824         if (usr_qf_name || grp_qf_name) {
2825                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2826                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2827
2828                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2829                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2830
2831                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2832                     ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2833                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2834                                  "format mixing");
2835                         return -EINVAL;
2836                 }
2837         }
2838 #endif
2839         return 1;
2840 }
2841
2842 static inline void ext4_show_quota_options(struct seq_file *seq,
2843                                            struct super_block *sb)
2844 {
2845 #if defined(CONFIG_QUOTA)
2846         struct ext4_sb_info *sbi = EXT4_SB(sb);
2847         char *usr_qf_name, *grp_qf_name;
2848
2849         if (sbi->s_jquota_fmt) {
2850                 char *fmtname = "";
2851
2852                 switch (sbi->s_jquota_fmt) {
2853                 case QFMT_VFS_OLD:
2854                         fmtname = "vfsold";
2855                         break;
2856                 case QFMT_VFS_V0:
2857                         fmtname = "vfsv0";
2858                         break;
2859                 case QFMT_VFS_V1:
2860                         fmtname = "vfsv1";
2861                         break;
2862                 }
2863                 seq_printf(seq, ",jqfmt=%s", fmtname);
2864         }
2865
2866         rcu_read_lock();
2867         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2868         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2869         if (usr_qf_name)
2870                 seq_show_option(seq, "usrjquota", usr_qf_name);
2871         if (grp_qf_name)
2872                 seq_show_option(seq, "grpjquota", grp_qf_name);
2873         rcu_read_unlock();
2874 #endif
2875 }
2876
2877 static const char *token2str(int token)
2878 {
2879         const struct fs_parameter_spec *spec;
2880
2881         for (spec = ext4_param_specs; spec->name != NULL; spec++)
2882                 if (spec->opt == token && !spec->type)
2883                         break;
2884         return spec->name;
2885 }
2886
2887 /*
2888  * Show an option if
2889  *  - it's set to a non-default value OR
2890  *  - if the per-sb default is different from the global default
2891  */
2892 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2893                               int nodefs)
2894 {
2895         struct ext4_sb_info *sbi = EXT4_SB(sb);
2896         struct ext4_super_block *es = sbi->s_es;
2897         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2898         const struct mount_opts *m;
2899         char sep = nodefs ? '\n' : ',';
2900
2901 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2902 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2903
2904         if (sbi->s_sb_block != 1)
2905                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2906
2907         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2908                 int want_set = m->flags & MOPT_SET;
2909                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2910                     m->flags & MOPT_SKIP)
2911                         continue;
2912                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2913                         continue; /* skip if same as the default */
2914                 if ((want_set &&
2915                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2916                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2917                         continue; /* select Opt_noFoo vs Opt_Foo */
2918                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2919         }
2920
2921         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2922             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2923                 SEQ_OPTS_PRINT("resuid=%u",
2924                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2925         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2926             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2927                 SEQ_OPTS_PRINT("resgid=%u",
2928                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2929         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2930         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2931                 SEQ_OPTS_PUTS("errors=remount-ro");
2932         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2933                 SEQ_OPTS_PUTS("errors=continue");
2934         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2935                 SEQ_OPTS_PUTS("errors=panic");
2936         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2937                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2938         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2939                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2940         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2941                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2942         if (nodefs || sbi->s_stripe)
2943                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2944         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2945                         (sbi->s_mount_opt ^ def_mount_opt)) {
2946                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2947                         SEQ_OPTS_PUTS("data=journal");
2948                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2949                         SEQ_OPTS_PUTS("data=ordered");
2950                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2951                         SEQ_OPTS_PUTS("data=writeback");
2952         }
2953         if (nodefs ||
2954             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2955                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2956                                sbi->s_inode_readahead_blks);
2957
2958         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2959                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2960                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2961         if (nodefs || sbi->s_max_dir_size_kb)
2962                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2963         if (test_opt(sb, DATA_ERR_ABORT))
2964                 SEQ_OPTS_PUTS("data_err=abort");
2965
2966         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2967
2968         if (sb->s_flags & SB_INLINECRYPT)
2969                 SEQ_OPTS_PUTS("inlinecrypt");
2970
2971         if (test_opt(sb, DAX_ALWAYS)) {
2972                 if (IS_EXT2_SB(sb))
2973                         SEQ_OPTS_PUTS("dax");
2974                 else
2975                         SEQ_OPTS_PUTS("dax=always");
2976         } else if (test_opt2(sb, DAX_NEVER)) {
2977                 SEQ_OPTS_PUTS("dax=never");
2978         } else if (test_opt2(sb, DAX_INODE)) {
2979                 SEQ_OPTS_PUTS("dax=inode");
2980         }
2981
2982         if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
2983                         !test_opt2(sb, MB_OPTIMIZE_SCAN)) {
2984                 SEQ_OPTS_PUTS("mb_optimize_scan=0");
2985         } else if (sbi->s_groups_count < MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
2986                         test_opt2(sb, MB_OPTIMIZE_SCAN)) {
2987                 SEQ_OPTS_PUTS("mb_optimize_scan=1");
2988         }
2989
2990         ext4_show_quota_options(seq, sb);
2991         return 0;
2992 }
2993
2994 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2995 {
2996         return _ext4_show_options(seq, root->d_sb, 0);
2997 }
2998
2999 int ext4_seq_options_show(struct seq_file *seq, void *offset)
3000 {
3001         struct super_block *sb = seq->private;
3002         int rc;
3003
3004         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
3005         rc = _ext4_show_options(seq, sb, 1);
3006         seq_puts(seq, "\n");
3007         return rc;
3008 }
3009
3010 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3011                             int read_only)
3012 {
3013         struct ext4_sb_info *sbi = EXT4_SB(sb);
3014         int err = 0;
3015
3016         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3017                 ext4_msg(sb, KERN_ERR, "revision level too high, "
3018                          "forcing read-only mode");
3019                 err = -EROFS;
3020                 goto done;
3021         }
3022         if (read_only)
3023                 goto done;
3024         if (!(sbi->s_mount_state & EXT4_VALID_FS))
3025                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3026                          "running e2fsck is recommended");
3027         else if (sbi->s_mount_state & EXT4_ERROR_FS)
3028                 ext4_msg(sb, KERN_WARNING,
3029                          "warning: mounting fs with errors, "
3030                          "running e2fsck is recommended");
3031         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3032                  le16_to_cpu(es->s_mnt_count) >=
3033                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3034                 ext4_msg(sb, KERN_WARNING,
3035                          "warning: maximal mount count reached, "
3036                          "running e2fsck is recommended");
3037         else if (le32_to_cpu(es->s_checkinterval) &&
3038                  (ext4_get_tstamp(es, s_lastcheck) +
3039                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3040                 ext4_msg(sb, KERN_WARNING,
3041                          "warning: checktime reached, "
3042                          "running e2fsck is recommended");
3043         if (!sbi->s_journal)
3044                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3045         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3046                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3047         le16_add_cpu(&es->s_mnt_count, 1);
3048         ext4_update_tstamp(es, s_mtime);
3049         if (sbi->s_journal) {
3050                 ext4_set_feature_journal_needs_recovery(sb);
3051                 if (ext4_has_feature_orphan_file(sb))
3052                         ext4_set_feature_orphan_present(sb);
3053         }
3054
3055         err = ext4_commit_super(sb);
3056 done:
3057         if (test_opt(sb, DEBUG))
3058                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3059                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3060                         sb->s_blocksize,
3061                         sbi->s_groups_count,
3062                         EXT4_BLOCKS_PER_GROUP(sb),
3063                         EXT4_INODES_PER_GROUP(sb),
3064                         sbi->s_mount_opt, sbi->s_mount_opt2);
3065         return err;
3066 }
3067
3068 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3069 {
3070         struct ext4_sb_info *sbi = EXT4_SB(sb);
3071         struct flex_groups **old_groups, **new_groups;
3072         int size, i, j;
3073
3074         if (!sbi->s_log_groups_per_flex)
3075                 return 0;
3076
3077         size = ext4_flex_group(sbi, ngroup - 1) + 1;
3078         if (size <= sbi->s_flex_groups_allocated)
3079                 return 0;
3080
3081         new_groups = kvzalloc(roundup_pow_of_two(size *
3082                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3083         if (!new_groups) {
3084                 ext4_msg(sb, KERN_ERR,
3085                          "not enough memory for %d flex group pointers", size);
3086                 return -ENOMEM;
3087         }
3088         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3089                 new_groups[i] = kvzalloc(roundup_pow_of_two(
3090                                          sizeof(struct flex_groups)),
3091                                          GFP_KERNEL);
3092                 if (!new_groups[i]) {
3093                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
3094                                 kvfree(new_groups[j]);
3095                         kvfree(new_groups);
3096                         ext4_msg(sb, KERN_ERR,
3097                                  "not enough memory for %d flex groups", size);
3098                         return -ENOMEM;
3099                 }
3100         }
3101         rcu_read_lock();
3102         old_groups = rcu_dereference(sbi->s_flex_groups);
3103         if (old_groups)
3104                 memcpy(new_groups, old_groups,
3105                        (sbi->s_flex_groups_allocated *
3106                         sizeof(struct flex_groups *)));
3107         rcu_read_unlock();
3108         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3109         sbi->s_flex_groups_allocated = size;
3110         if (old_groups)
3111                 ext4_kvfree_array_rcu(old_groups);
3112         return 0;
3113 }
3114
3115 static int ext4_fill_flex_info(struct super_block *sb)
3116 {
3117         struct ext4_sb_info *sbi = EXT4_SB(sb);
3118         struct ext4_group_desc *gdp = NULL;
3119         struct flex_groups *fg;
3120         ext4_group_t flex_group;
3121         int i, err;
3122
3123         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3124         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3125                 sbi->s_log_groups_per_flex = 0;
3126                 return 1;
3127         }
3128
3129         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3130         if (err)
3131                 goto failed;
3132
3133         for (i = 0; i < sbi->s_groups_count; i++) {
3134                 gdp = ext4_get_group_desc(sb, i, NULL);
3135
3136                 flex_group = ext4_flex_group(sbi, i);
3137                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3138                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3139                 atomic64_add(ext4_free_group_clusters(sb, gdp),
3140                              &fg->free_clusters);
3141                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3142         }
3143
3144         return 1;
3145 failed:
3146         return 0;
3147 }
3148
3149 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3150                                    struct ext4_group_desc *gdp)
3151 {
3152         int offset = offsetof(struct ext4_group_desc, bg_checksum);
3153         __u16 crc = 0;
3154         __le32 le_group = cpu_to_le32(block_group);
3155         struct ext4_sb_info *sbi = EXT4_SB(sb);
3156
3157         if (ext4_has_metadata_csum(sbi->s_sb)) {
3158                 /* Use new metadata_csum algorithm */
3159                 __u32 csum32;
3160                 __u16 dummy_csum = 0;
3161
3162                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
3163                                      sizeof(le_group));
3164                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
3165                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
3166                                      sizeof(dummy_csum));
3167                 offset += sizeof(dummy_csum);
3168                 if (offset < sbi->s_desc_size)
3169                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
3170                                              sbi->s_desc_size - offset);
3171
3172                 crc = csum32 & 0xFFFF;
3173                 goto out;
3174         }
3175
3176         /* old crc16 code */
3177         if (!ext4_has_feature_gdt_csum(sb))
3178                 return 0;
3179
3180         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3181         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3182         crc = crc16(crc, (__u8 *)gdp, offset);
3183         offset += sizeof(gdp->bg_checksum); /* skip checksum */
3184         /* for checksum of struct ext4_group_desc do the rest...*/
3185         if (ext4_has_feature_64bit(sb) &&
3186             offset < le16_to_cpu(sbi->s_es->s_desc_size))
3187                 crc = crc16(crc, (__u8 *)gdp + offset,
3188                             le16_to_cpu(sbi->s_es->s_desc_size) -
3189                                 offset);
3190
3191 out:
3192         return cpu_to_le16(crc);
3193 }
3194
3195 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3196                                 struct ext4_group_desc *gdp)
3197 {
3198         if (ext4_has_group_desc_csum(sb) &&
3199             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3200                 return 0;
3201
3202         return 1;
3203 }
3204
3205 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3206                               struct ext4_group_desc *gdp)
3207 {
3208         if (!ext4_has_group_desc_csum(sb))
3209                 return;
3210         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3211 }
3212
3213 /* Called at mount-time, super-block is locked */
3214 static int ext4_check_descriptors(struct super_block *sb,
3215                                   ext4_fsblk_t sb_block,
3216                                   ext4_group_t *first_not_zeroed)
3217 {
3218         struct ext4_sb_info *sbi = EXT4_SB(sb);
3219         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3220         ext4_fsblk_t last_block;
3221         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3222         ext4_fsblk_t block_bitmap;
3223         ext4_fsblk_t inode_bitmap;
3224         ext4_fsblk_t inode_table;
3225         int flexbg_flag = 0;
3226         ext4_group_t i, grp = sbi->s_groups_count;
3227
3228         if (ext4_has_feature_flex_bg(sb))
3229                 flexbg_flag = 1;
3230
3231         ext4_debug("Checking group descriptors");
3232
3233         for (i = 0; i < sbi->s_groups_count; i++) {
3234                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3235
3236                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
3237                         last_block = ext4_blocks_count(sbi->s_es) - 1;
3238                 else
3239                         last_block = first_block +
3240                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
3241
3242                 if ((grp == sbi->s_groups_count) &&
3243                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3244                         grp = i;
3245
3246                 block_bitmap = ext4_block_bitmap(sb, gdp);
3247                 if (block_bitmap == sb_block) {
3248                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3249                                  "Block bitmap for group %u overlaps "
3250                                  "superblock", i);
3251                         if (!sb_rdonly(sb))
3252                                 return 0;
3253                 }
3254                 if (block_bitmap >= sb_block + 1 &&
3255                     block_bitmap <= last_bg_block) {
3256                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3257                                  "Block bitmap for group %u overlaps "
3258                                  "block group descriptors", i);
3259                         if (!sb_rdonly(sb))
3260                                 return 0;
3261                 }
3262                 if (block_bitmap < first_block || block_bitmap > last_block) {
3263                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3264                                "Block bitmap for group %u not in group "
3265                                "(block %llu)!", i, block_bitmap);
3266                         return 0;
3267                 }
3268                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
3269                 if (inode_bitmap == sb_block) {
3270                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3271                                  "Inode bitmap for group %u overlaps "
3272                                  "superblock", i);
3273                         if (!sb_rdonly(sb))
3274                                 return 0;
3275                 }
3276                 if (inode_bitmap >= sb_block + 1 &&
3277                     inode_bitmap <= last_bg_block) {
3278                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3279                                  "Inode bitmap for group %u overlaps "
3280                                  "block group descriptors", i);
3281                         if (!sb_rdonly(sb))
3282                                 return 0;
3283                 }
3284                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
3285                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3286                                "Inode bitmap for group %u not in group "
3287                                "(block %llu)!", i, inode_bitmap);
3288                         return 0;
3289                 }
3290                 inode_table = ext4_inode_table(sb, gdp);
3291                 if (inode_table == sb_block) {
3292                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3293                                  "Inode table for group %u overlaps "
3294                                  "superblock", i);
3295                         if (!sb_rdonly(sb))
3296                                 return 0;
3297                 }
3298                 if (inode_table >= sb_block + 1 &&
3299                     inode_table <= last_bg_block) {
3300                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3301                                  "Inode table for group %u overlaps "
3302                                  "block group descriptors", i);
3303                         if (!sb_rdonly(sb))
3304                                 return 0;
3305                 }
3306                 if (inode_table < first_block ||
3307                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
3308                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3309                                "Inode table for group %u not in group "
3310                                "(block %llu)!", i, inode_table);
3311                         return 0;
3312                 }
3313                 ext4_lock_group(sb, i);
3314                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3315                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3316                                  "Checksum for group %u failed (%u!=%u)",
3317                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3318                                      gdp)), le16_to_cpu(gdp->bg_checksum));
3319                         if (!sb_rdonly(sb)) {
3320                                 ext4_unlock_group(sb, i);
3321                                 return 0;
3322                         }
3323                 }
3324                 ext4_unlock_group(sb, i);
3325                 if (!flexbg_flag)
3326                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
3327         }
3328         if (NULL != first_not_zeroed)
3329                 *first_not_zeroed = grp;
3330         return 1;
3331 }
3332
3333 /*
3334  * Maximal extent format file size.
3335  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3336  * extent format containers, within a sector_t, and within i_blocks
3337  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3338  * so that won't be a limiting factor.
3339  *
3340  * However there is other limiting factor. We do store extents in the form
3341  * of starting block and length, hence the resulting length of the extent
3342  * covering maximum file size must fit into on-disk format containers as
3343  * well. Given that length is always by 1 unit bigger than max unit (because
3344  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3345  *
3346  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3347  */
3348 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3349 {
3350         loff_t res;
3351         loff_t upper_limit = MAX_LFS_FILESIZE;
3352
3353         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3354
3355         if (!has_huge_files) {
3356                 upper_limit = (1LL << 32) - 1;
3357
3358                 /* total blocks in file system block size */
3359                 upper_limit >>= (blkbits - 9);
3360                 upper_limit <<= blkbits;
3361         }
3362
3363         /*
3364          * 32-bit extent-start container, ee_block. We lower the maxbytes
3365          * by one fs block, so ee_len can cover the extent of maximum file
3366          * size
3367          */
3368         res = (1LL << 32) - 1;
3369         res <<= blkbits;
3370
3371         /* Sanity check against vm- & vfs- imposed limits */
3372         if (res > upper_limit)
3373                 res = upper_limit;
3374
3375         return res;
3376 }
3377
3378 /*
3379  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3380  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3381  * We need to be 1 filesystem block less than the 2^48 sector limit.
3382  */
3383 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3384 {
3385         loff_t upper_limit, res = EXT4_NDIR_BLOCKS;
3386         int meta_blocks;
3387         unsigned int ppb = 1 << (bits - 2);
3388
3389         /*
3390          * This is calculated to be the largest file size for a dense, block
3391          * mapped file such that the file's total number of 512-byte sectors,
3392          * including data and all indirect blocks, does not exceed (2^48 - 1).
3393          *
3394          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3395          * number of 512-byte sectors of the file.
3396          */
3397         if (!has_huge_files) {
3398                 /*
3399                  * !has_huge_files or implies that the inode i_block field
3400                  * represents total file blocks in 2^32 512-byte sectors ==
3401                  * size of vfs inode i_blocks * 8
3402                  */
3403                 upper_limit = (1LL << 32) - 1;
3404
3405                 /* total blocks in file system block size */
3406                 upper_limit >>= (bits - 9);
3407
3408         } else {
3409                 /*
3410                  * We use 48 bit ext4_inode i_blocks
3411                  * With EXT4_HUGE_FILE_FL set the i_blocks
3412                  * represent total number of blocks in
3413                  * file system block size
3414                  */
3415                 upper_limit = (1LL << 48) - 1;
3416
3417         }
3418
3419         /* Compute how many blocks we can address by block tree */
3420         res += ppb;
3421         res += ppb * ppb;
3422         res += ((loff_t)ppb) * ppb * ppb;
3423         /* Compute how many metadata blocks are needed */
3424         meta_blocks = 1;
3425         meta_blocks += 1 + ppb;
3426         meta_blocks += 1 + ppb + ppb * ppb;
3427         /* Does block tree limit file size? */
3428         if (res + meta_blocks <= upper_limit)
3429                 goto check_lfs;
3430
3431         res = upper_limit;
3432         /* How many metadata blocks are needed for addressing upper_limit? */
3433         upper_limit -= EXT4_NDIR_BLOCKS;
3434         /* indirect blocks */
3435         meta_blocks = 1;
3436         upper_limit -= ppb;
3437         /* double indirect blocks */
3438         if (upper_limit < ppb * ppb) {
3439                 meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb);
3440                 res -= meta_blocks;
3441                 goto check_lfs;
3442         }
3443         meta_blocks += 1 + ppb;
3444         upper_limit -= ppb * ppb;
3445         /* tripple indirect blocks for the rest */
3446         meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb) +
3447                 DIV_ROUND_UP_ULL(upper_limit, ppb*ppb);
3448         res -= meta_blocks;
3449 check_lfs:
3450         res <<= bits;
3451         if (res > MAX_LFS_FILESIZE)
3452                 res = MAX_LFS_FILESIZE;
3453
3454         return res;
3455 }
3456
3457 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3458                                    ext4_fsblk_t logical_sb_block, int nr)
3459 {
3460         struct ext4_sb_info *sbi = EXT4_SB(sb);
3461         ext4_group_t bg, first_meta_bg;
3462         int has_super = 0;
3463
3464         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3465
3466         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3467                 return logical_sb_block + nr + 1;
3468         bg = sbi->s_desc_per_block * nr;
3469         if (ext4_bg_has_super(sb, bg))
3470                 has_super = 1;
3471
3472         /*
3473          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3474          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3475          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3476          * compensate.
3477          */
3478         if (sb->s_blocksize == 1024 && nr == 0 &&
3479             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3480                 has_super++;
3481
3482         return (has_super + ext4_group_first_block_no(sb, bg));
3483 }
3484
3485 /**
3486  * ext4_get_stripe_size: Get the stripe size.
3487  * @sbi: In memory super block info
3488  *
3489  * If we have specified it via mount option, then
3490  * use the mount option value. If the value specified at mount time is
3491  * greater than the blocks per group use the super block value.
3492  * If the super block value is greater than blocks per group return 0.
3493  * Allocator needs it be less than blocks per group.
3494  *
3495  */
3496 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3497 {
3498         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3499         unsigned long stripe_width =
3500                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3501         int ret;
3502
3503         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3504                 ret = sbi->s_stripe;
3505         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3506                 ret = stripe_width;
3507         else if (stride && stride <= sbi->s_blocks_per_group)
3508                 ret = stride;
3509         else
3510                 ret = 0;
3511
3512         /*
3513          * If the stripe width is 1, this makes no sense and
3514          * we set it to 0 to turn off stripe handling code.
3515          */
3516         if (ret <= 1)
3517                 ret = 0;
3518
3519         return ret;
3520 }
3521
3522 /*
3523  * Check whether this filesystem can be mounted based on
3524  * the features present and the RDONLY/RDWR mount requested.
3525  * Returns 1 if this filesystem can be mounted as requested,
3526  * 0 if it cannot be.
3527  */
3528 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3529 {
3530         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3531                 ext4_msg(sb, KERN_ERR,
3532                         "Couldn't mount because of "
3533                         "unsupported optional features (%x)",
3534                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3535                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3536                 return 0;
3537         }
3538
3539 #if !IS_ENABLED(CONFIG_UNICODE)
3540         if (ext4_has_feature_casefold(sb)) {
3541                 ext4_msg(sb, KERN_ERR,
3542                          "Filesystem with casefold feature cannot be "
3543                          "mounted without CONFIG_UNICODE");
3544                 return 0;
3545         }
3546 #endif
3547
3548         if (readonly)
3549                 return 1;
3550
3551         if (ext4_has_feature_readonly(sb)) {
3552                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3553                 sb->s_flags |= SB_RDONLY;
3554                 return 1;
3555         }
3556
3557         /* Check that feature set is OK for a read-write mount */
3558         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3559                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3560                          "unsupported optional features (%x)",
3561                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3562                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3563                 return 0;
3564         }
3565         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3566                 ext4_msg(sb, KERN_ERR,
3567                          "Can't support bigalloc feature without "
3568                          "extents feature\n");
3569                 return 0;
3570         }
3571
3572 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3573         if (!readonly && (ext4_has_feature_quota(sb) ||
3574                           ext4_has_feature_project(sb))) {
3575                 ext4_msg(sb, KERN_ERR,
3576                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3577                 return 0;
3578         }
3579 #endif  /* CONFIG_QUOTA */
3580         return 1;
3581 }
3582
3583 /*
3584  * This function is called once a day if we have errors logged
3585  * on the file system
3586  */
3587 static void print_daily_error_info(struct timer_list *t)
3588 {
3589         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3590         struct super_block *sb = sbi->s_sb;
3591         struct ext4_super_block *es = sbi->s_es;
3592
3593         if (es->s_error_count)
3594                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3595                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3596                          le32_to_cpu(es->s_error_count));
3597         if (es->s_first_error_time) {
3598                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3599                        sb->s_id,
3600                        ext4_get_tstamp(es, s_first_error_time),
3601                        (int) sizeof(es->s_first_error_func),
3602                        es->s_first_error_func,
3603                        le32_to_cpu(es->s_first_error_line));
3604                 if (es->s_first_error_ino)
3605                         printk(KERN_CONT ": inode %u",
3606                                le32_to_cpu(es->s_first_error_ino));
3607                 if (es->s_first_error_block)
3608                         printk(KERN_CONT ": block %llu", (unsigned long long)
3609                                le64_to_cpu(es->s_first_error_block));
3610                 printk(KERN_CONT "\n");
3611         }
3612         if (es->s_last_error_time) {
3613                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3614                        sb->s_id,
3615                        ext4_get_tstamp(es, s_last_error_time),
3616                        (int) sizeof(es->s_last_error_func),
3617                        es->s_last_error_func,
3618                        le32_to_cpu(es->s_last_error_line));
3619                 if (es->s_last_error_ino)
3620                         printk(KERN_CONT ": inode %u",
3621                                le32_to_cpu(es->s_last_error_ino));
3622                 if (es->s_last_error_block)
3623                         printk(KERN_CONT ": block %llu", (unsigned long long)
3624                                le64_to_cpu(es->s_last_error_block));
3625                 printk(KERN_CONT "\n");
3626         }
3627         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3628 }
3629
3630 /* Find next suitable group and run ext4_init_inode_table */
3631 static int ext4_run_li_request(struct ext4_li_request *elr)
3632 {
3633         struct ext4_group_desc *gdp = NULL;
3634         struct super_block *sb = elr->lr_super;
3635         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3636         ext4_group_t group = elr->lr_next_group;
3637         unsigned int prefetch_ios = 0;
3638         int ret = 0;
3639         u64 start_time;
3640
3641         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3642                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3643                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3644                 if (prefetch_ios)
3645                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3646                                               prefetch_ios);
3647                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3648                                             prefetch_ios);
3649                 if (group >= elr->lr_next_group) {
3650                         ret = 1;
3651                         if (elr->lr_first_not_zeroed != ngroups &&
3652                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3653                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3654                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3655                                 ret = 0;
3656                         }
3657                 }
3658                 return ret;
3659         }
3660
3661         for (; group < ngroups; group++) {
3662                 gdp = ext4_get_group_desc(sb, group, NULL);
3663                 if (!gdp) {
3664                         ret = 1;
3665                         break;
3666                 }
3667
3668                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3669                         break;
3670         }
3671
3672         if (group >= ngroups)
3673                 ret = 1;
3674
3675         if (!ret) {
3676                 start_time = ktime_get_real_ns();
3677                 ret = ext4_init_inode_table(sb, group,
3678                                             elr->lr_timeout ? 0 : 1);
3679                 trace_ext4_lazy_itable_init(sb, group);
3680                 if (elr->lr_timeout == 0) {
3681                         elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3682                                 EXT4_SB(elr->lr_super)->s_li_wait_mult);
3683                 }
3684                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3685                 elr->lr_next_group = group + 1;
3686         }
3687         return ret;
3688 }
3689
3690 /*
3691  * Remove lr_request from the list_request and free the
3692  * request structure. Should be called with li_list_mtx held
3693  */
3694 static void ext4_remove_li_request(struct ext4_li_request *elr)
3695 {
3696         if (!elr)
3697                 return;
3698
3699         list_del(&elr->lr_request);
3700         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3701         kfree(elr);
3702 }
3703
3704 static void ext4_unregister_li_request(struct super_block *sb)
3705 {
3706         mutex_lock(&ext4_li_mtx);
3707         if (!ext4_li_info) {
3708                 mutex_unlock(&ext4_li_mtx);
3709                 return;
3710         }
3711
3712         mutex_lock(&ext4_li_info->li_list_mtx);
3713         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3714         mutex_unlock(&ext4_li_info->li_list_mtx);
3715         mutex_unlock(&ext4_li_mtx);
3716 }
3717
3718 static struct task_struct *ext4_lazyinit_task;
3719
3720 /*
3721  * This is the function where ext4lazyinit thread lives. It walks
3722  * through the request list searching for next scheduled filesystem.
3723  * When such a fs is found, run the lazy initialization request
3724  * (ext4_rn_li_request) and keep track of the time spend in this
3725  * function. Based on that time we compute next schedule time of
3726  * the request. When walking through the list is complete, compute
3727  * next waking time and put itself into sleep.
3728  */
3729 static int ext4_lazyinit_thread(void *arg)
3730 {
3731         struct ext4_lazy_init *eli = arg;
3732         struct list_head *pos, *n;
3733         struct ext4_li_request *elr;
3734         unsigned long next_wakeup, cur;
3735
3736         BUG_ON(NULL == eli);
3737         set_freezable();
3738
3739 cont_thread:
3740         while (true) {
3741                 next_wakeup = MAX_JIFFY_OFFSET;
3742
3743                 mutex_lock(&eli->li_list_mtx);
3744                 if (list_empty(&eli->li_request_list)) {
3745                         mutex_unlock(&eli->li_list_mtx);
3746                         goto exit_thread;
3747                 }
3748                 list_for_each_safe(pos, n, &eli->li_request_list) {
3749                         int err = 0;
3750                         int progress = 0;
3751                         elr = list_entry(pos, struct ext4_li_request,
3752                                          lr_request);
3753
3754                         if (time_before(jiffies, elr->lr_next_sched)) {
3755                                 if (time_before(elr->lr_next_sched, next_wakeup))
3756                                         next_wakeup = elr->lr_next_sched;
3757                                 continue;
3758                         }
3759                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3760                                 if (sb_start_write_trylock(elr->lr_super)) {
3761                                         progress = 1;
3762                                         /*
3763                                          * We hold sb->s_umount, sb can not
3764                                          * be removed from the list, it is
3765                                          * now safe to drop li_list_mtx
3766                                          */
3767                                         mutex_unlock(&eli->li_list_mtx);
3768                                         err = ext4_run_li_request(elr);
3769                                         sb_end_write(elr->lr_super);
3770                                         mutex_lock(&eli->li_list_mtx);
3771                                         n = pos->next;
3772                                 }
3773                                 up_read((&elr->lr_super->s_umount));
3774                         }
3775                         /* error, remove the lazy_init job */
3776                         if (err) {
3777                                 ext4_remove_li_request(elr);
3778                                 continue;
3779                         }
3780                         if (!progress) {
3781                                 elr->lr_next_sched = jiffies +
3782                                         prandom_u32_max(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3783                         }
3784                         if (time_before(elr->lr_next_sched, next_wakeup))
3785                                 next_wakeup = elr->lr_next_sched;
3786                 }
3787                 mutex_unlock(&eli->li_list_mtx);
3788
3789                 try_to_freeze();
3790
3791                 cur = jiffies;
3792                 if ((time_after_eq(cur, next_wakeup)) ||
3793                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3794                         cond_resched();
3795                         continue;
3796                 }
3797
3798                 schedule_timeout_interruptible(next_wakeup - cur);
3799
3800                 if (kthread_should_stop()) {
3801                         ext4_clear_request_list();
3802                         goto exit_thread;
3803                 }
3804         }
3805
3806 exit_thread:
3807         /*
3808          * It looks like the request list is empty, but we need
3809          * to check it under the li_list_mtx lock, to prevent any
3810          * additions into it, and of course we should lock ext4_li_mtx
3811          * to atomically free the list and ext4_li_info, because at
3812          * this point another ext4 filesystem could be registering
3813          * new one.
3814          */
3815         mutex_lock(&ext4_li_mtx);
3816         mutex_lock(&eli->li_list_mtx);
3817         if (!list_empty(&eli->li_request_list)) {
3818                 mutex_unlock(&eli->li_list_mtx);
3819                 mutex_unlock(&ext4_li_mtx);
3820                 goto cont_thread;
3821         }
3822         mutex_unlock(&eli->li_list_mtx);
3823         kfree(ext4_li_info);
3824         ext4_li_info = NULL;
3825         mutex_unlock(&ext4_li_mtx);
3826
3827         return 0;
3828 }
3829
3830 static void ext4_clear_request_list(void)
3831 {
3832         struct list_head *pos, *n;
3833         struct ext4_li_request *elr;
3834
3835         mutex_lock(&ext4_li_info->li_list_mtx);
3836         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3837                 elr = list_entry(pos, struct ext4_li_request,
3838                                  lr_request);
3839                 ext4_remove_li_request(elr);
3840         }
3841         mutex_unlock(&ext4_li_info->li_list_mtx);
3842 }
3843
3844 static int ext4_run_lazyinit_thread(void)
3845 {
3846         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3847                                          ext4_li_info, "ext4lazyinit");
3848         if (IS_ERR(ext4_lazyinit_task)) {
3849                 int err = PTR_ERR(ext4_lazyinit_task);
3850                 ext4_clear_request_list();
3851                 kfree(ext4_li_info);
3852                 ext4_li_info = NULL;
3853                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3854                                  "initialization thread\n",
3855                                  err);
3856                 return err;
3857         }
3858         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3859         return 0;
3860 }
3861
3862 /*
3863  * Check whether it make sense to run itable init. thread or not.
3864  * If there is at least one uninitialized inode table, return
3865  * corresponding group number, else the loop goes through all
3866  * groups and return total number of groups.
3867  */
3868 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3869 {
3870         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3871         struct ext4_group_desc *gdp = NULL;
3872
3873         if (!ext4_has_group_desc_csum(sb))
3874                 return ngroups;
3875
3876         for (group = 0; group < ngroups; group++) {
3877                 gdp = ext4_get_group_desc(sb, group, NULL);
3878                 if (!gdp)
3879                         continue;
3880
3881                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3882                         break;
3883         }
3884
3885         return group;
3886 }
3887
3888 static int ext4_li_info_new(void)
3889 {
3890         struct ext4_lazy_init *eli = NULL;
3891
3892         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3893         if (!eli)
3894                 return -ENOMEM;
3895
3896         INIT_LIST_HEAD(&eli->li_request_list);
3897         mutex_init(&eli->li_list_mtx);
3898
3899         eli->li_state |= EXT4_LAZYINIT_QUIT;
3900
3901         ext4_li_info = eli;
3902
3903         return 0;
3904 }
3905
3906 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3907                                             ext4_group_t start)
3908 {
3909         struct ext4_li_request *elr;
3910
3911         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3912         if (!elr)
3913                 return NULL;
3914
3915         elr->lr_super = sb;
3916         elr->lr_first_not_zeroed = start;
3917         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3918                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3919                 elr->lr_next_group = start;
3920         } else {
3921                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3922         }
3923
3924         /*
3925          * Randomize first schedule time of the request to
3926          * spread the inode table initialization requests
3927          * better.
3928          */
3929         elr->lr_next_sched = jiffies + prandom_u32_max(
3930                                 EXT4_DEF_LI_MAX_START_DELAY * HZ);
3931         return elr;
3932 }
3933
3934 int ext4_register_li_request(struct super_block *sb,
3935                              ext4_group_t first_not_zeroed)
3936 {
3937         struct ext4_sb_info *sbi = EXT4_SB(sb);
3938         struct ext4_li_request *elr = NULL;
3939         ext4_group_t ngroups = sbi->s_groups_count;
3940         int ret = 0;
3941
3942         mutex_lock(&ext4_li_mtx);
3943         if (sbi->s_li_request != NULL) {
3944                 /*
3945                  * Reset timeout so it can be computed again, because
3946                  * s_li_wait_mult might have changed.
3947                  */
3948                 sbi->s_li_request->lr_timeout = 0;
3949                 goto out;
3950         }
3951
3952         if (sb_rdonly(sb) ||
3953             (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
3954              (first_not_zeroed == ngroups || !test_opt(sb, INIT_INODE_TABLE))))
3955                 goto out;
3956
3957         elr = ext4_li_request_new(sb, first_not_zeroed);
3958         if (!elr) {
3959                 ret = -ENOMEM;
3960                 goto out;
3961         }
3962
3963         if (NULL == ext4_li_info) {
3964                 ret = ext4_li_info_new();
3965                 if (ret)
3966                         goto out;
3967         }
3968
3969         mutex_lock(&ext4_li_info->li_list_mtx);
3970         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3971         mutex_unlock(&ext4_li_info->li_list_mtx);
3972
3973         sbi->s_li_request = elr;
3974         /*
3975          * set elr to NULL here since it has been inserted to
3976          * the request_list and the removal and free of it is
3977          * handled by ext4_clear_request_list from now on.
3978          */
3979         elr = NULL;
3980
3981         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3982                 ret = ext4_run_lazyinit_thread();
3983                 if (ret)
3984                         goto out;
3985         }
3986 out:
3987         mutex_unlock(&ext4_li_mtx);
3988         if (ret)
3989                 kfree(elr);
3990         return ret;
3991 }
3992
3993 /*
3994  * We do not need to lock anything since this is called on
3995  * module unload.
3996  */
3997 static void ext4_destroy_lazyinit_thread(void)
3998 {
3999         /*
4000          * If thread exited earlier
4001          * there's nothing to be done.
4002          */
4003         if (!ext4_li_info || !ext4_lazyinit_task)
4004                 return;
4005
4006         kthread_stop(ext4_lazyinit_task);
4007 }
4008
4009 static int set_journal_csum_feature_set(struct super_block *sb)
4010 {
4011         int ret = 1;
4012         int compat, incompat;
4013         struct ext4_sb_info *sbi = EXT4_SB(sb);
4014
4015         if (ext4_has_metadata_csum(sb)) {
4016                 /* journal checksum v3 */
4017                 compat = 0;
4018                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4019         } else {
4020                 /* journal checksum v1 */
4021                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4022                 incompat = 0;
4023         }
4024
4025         jbd2_journal_clear_features(sbi->s_journal,
4026                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4027                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4028                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
4029         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4030                 ret = jbd2_journal_set_features(sbi->s_journal,
4031                                 compat, 0,
4032                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4033                                 incompat);
4034         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4035                 ret = jbd2_journal_set_features(sbi->s_journal,
4036                                 compat, 0,
4037                                 incompat);
4038                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4039                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4040         } else {
4041                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4042                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4043         }
4044
4045         return ret;
4046 }
4047
4048 /*
4049  * Note: calculating the overhead so we can be compatible with
4050  * historical BSD practice is quite difficult in the face of
4051  * clusters/bigalloc.  This is because multiple metadata blocks from
4052  * different block group can end up in the same allocation cluster.
4053  * Calculating the exact overhead in the face of clustered allocation
4054  * requires either O(all block bitmaps) in memory or O(number of block
4055  * groups**2) in time.  We will still calculate the superblock for
4056  * older file systems --- and if we come across with a bigalloc file
4057  * system with zero in s_overhead_clusters the estimate will be close to
4058  * correct especially for very large cluster sizes --- but for newer
4059  * file systems, it's better to calculate this figure once at mkfs
4060  * time, and store it in the superblock.  If the superblock value is
4061  * present (even for non-bigalloc file systems), we will use it.
4062  */
4063 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4064                           char *buf)
4065 {
4066         struct ext4_sb_info     *sbi = EXT4_SB(sb);
4067         struct ext4_group_desc  *gdp;
4068         ext4_fsblk_t            first_block, last_block, b;
4069         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
4070         int                     s, j, count = 0;
4071         int                     has_super = ext4_bg_has_super(sb, grp);
4072
4073         if (!ext4_has_feature_bigalloc(sb))
4074                 return (has_super + ext4_bg_num_gdb(sb, grp) +
4075                         (has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
4076                         sbi->s_itb_per_group + 2);
4077
4078         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4079                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
4080         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4081         for (i = 0; i < ngroups; i++) {
4082                 gdp = ext4_get_group_desc(sb, i, NULL);
4083                 b = ext4_block_bitmap(sb, gdp);
4084                 if (b >= first_block && b <= last_block) {
4085                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4086                         count++;
4087                 }
4088                 b = ext4_inode_bitmap(sb, gdp);
4089                 if (b >= first_block && b <= last_block) {
4090                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4091                         count++;
4092                 }
4093                 b = ext4_inode_table(sb, gdp);
4094                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4095                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4096                                 int c = EXT4_B2C(sbi, b - first_block);
4097                                 ext4_set_bit(c, buf);
4098                                 count++;
4099                         }
4100                 if (i != grp)
4101                         continue;
4102                 s = 0;
4103                 if (ext4_bg_has_super(sb, grp)) {
4104                         ext4_set_bit(s++, buf);
4105                         count++;
4106                 }
4107                 j = ext4_bg_num_gdb(sb, grp);
4108                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4109                         ext4_error(sb, "Invalid number of block group "
4110                                    "descriptor blocks: %d", j);
4111                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4112                 }
4113                 count += j;
4114                 for (; j > 0; j--)
4115                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4116         }
4117         if (!count)
4118                 return 0;
4119         return EXT4_CLUSTERS_PER_GROUP(sb) -
4120                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4121 }
4122
4123 /*
4124  * Compute the overhead and stash it in sbi->s_overhead
4125  */
4126 int ext4_calculate_overhead(struct super_block *sb)
4127 {
4128         struct ext4_sb_info *sbi = EXT4_SB(sb);
4129         struct ext4_super_block *es = sbi->s_es;
4130         struct inode *j_inode;
4131         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4132         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4133         ext4_fsblk_t overhead = 0;
4134         char *buf = (char *) get_zeroed_page(GFP_NOFS);
4135
4136         if (!buf)
4137                 return -ENOMEM;
4138
4139         /*
4140          * Compute the overhead (FS structures).  This is constant
4141          * for a given filesystem unless the number of block groups
4142          * changes so we cache the previous value until it does.
4143          */
4144
4145         /*
4146          * All of the blocks before first_data_block are overhead
4147          */
4148         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4149
4150         /*
4151          * Add the overhead found in each block group
4152          */
4153         for (i = 0; i < ngroups; i++) {
4154                 int blks;
4155
4156                 blks = count_overhead(sb, i, buf);
4157                 overhead += blks;
4158                 if (blks)
4159                         memset(buf, 0, PAGE_SIZE);
4160                 cond_resched();
4161         }
4162
4163         /*
4164          * Add the internal journal blocks whether the journal has been
4165          * loaded or not
4166          */
4167         if (sbi->s_journal && !sbi->s_journal_bdev)
4168                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4169         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4170                 /* j_inum for internal journal is non-zero */
4171                 j_inode = ext4_get_journal_inode(sb, j_inum);
4172                 if (j_inode) {
4173                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4174                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
4175                         iput(j_inode);
4176                 } else {
4177                         ext4_msg(sb, KERN_ERR, "can't get journal size");
4178                 }
4179         }
4180         sbi->s_overhead = overhead;
4181         smp_wmb();
4182         free_page((unsigned long) buf);
4183         return 0;
4184 }
4185
4186 static void ext4_set_resv_clusters(struct super_block *sb)
4187 {
4188         ext4_fsblk_t resv_clusters;
4189         struct ext4_sb_info *sbi = EXT4_SB(sb);
4190
4191         /*
4192          * There's no need to reserve anything when we aren't using extents.
4193          * The space estimates are exact, there are no unwritten extents,
4194          * hole punching doesn't need new metadata... This is needed especially
4195          * to keep ext2/3 backward compatibility.
4196          */
4197         if (!ext4_has_feature_extents(sb))
4198                 return;
4199         /*
4200          * By default we reserve 2% or 4096 clusters, whichever is smaller.
4201          * This should cover the situations where we can not afford to run
4202          * out of space like for example punch hole, or converting
4203          * unwritten extents in delalloc path. In most cases such
4204          * allocation would require 1, or 2 blocks, higher numbers are
4205          * very rare.
4206          */
4207         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4208                          sbi->s_cluster_bits);
4209
4210         do_div(resv_clusters, 50);
4211         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4212
4213         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4214 }
4215
4216 static const char *ext4_quota_mode(struct super_block *sb)
4217 {
4218 #ifdef CONFIG_QUOTA
4219         if (!ext4_quota_capable(sb))
4220                 return "none";
4221
4222         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4223                 return "journalled";
4224         else
4225                 return "writeback";
4226 #else
4227         return "disabled";
4228 #endif
4229 }
4230
4231 static void ext4_setup_csum_trigger(struct super_block *sb,
4232                                     enum ext4_journal_trigger_type type,
4233                                     void (*trigger)(
4234                                         struct jbd2_buffer_trigger_type *type,
4235                                         struct buffer_head *bh,
4236                                         void *mapped_data,
4237                                         size_t size))
4238 {
4239         struct ext4_sb_info *sbi = EXT4_SB(sb);
4240
4241         sbi->s_journal_triggers[type].sb = sb;
4242         sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4243 }
4244
4245 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4246 {
4247         if (!sbi)
4248                 return;
4249
4250         kfree(sbi->s_blockgroup_lock);
4251         fs_put_dax(sbi->s_daxdev, NULL);
4252         kfree(sbi);
4253 }
4254
4255 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4256 {
4257         struct ext4_sb_info *sbi;
4258
4259         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4260         if (!sbi)
4261                 return NULL;
4262
4263         sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
4264                                            NULL, NULL);
4265
4266         sbi->s_blockgroup_lock =
4267                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4268
4269         if (!sbi->s_blockgroup_lock)
4270                 goto err_out;
4271
4272         sb->s_fs_info = sbi;
4273         sbi->s_sb = sb;
4274         return sbi;
4275 err_out:
4276         fs_put_dax(sbi->s_daxdev, NULL);
4277         kfree(sbi);
4278         return NULL;
4279 }
4280
4281 static void ext4_set_def_opts(struct super_block *sb,
4282                               struct ext4_super_block *es)
4283 {
4284         unsigned long def_mount_opts;
4285
4286         /* Set defaults before we parse the mount options */
4287         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4288         set_opt(sb, INIT_INODE_TABLE);
4289         if (def_mount_opts & EXT4_DEFM_DEBUG)
4290                 set_opt(sb, DEBUG);
4291         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4292                 set_opt(sb, GRPID);
4293         if (def_mount_opts & EXT4_DEFM_UID16)
4294                 set_opt(sb, NO_UID32);
4295         /* xattr user namespace & acls are now defaulted on */
4296         set_opt(sb, XATTR_USER);
4297 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4298         set_opt(sb, POSIX_ACL);
4299 #endif
4300         if (ext4_has_feature_fast_commit(sb))
4301                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4302         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4303         if (ext4_has_metadata_csum(sb))
4304                 set_opt(sb, JOURNAL_CHECKSUM);
4305
4306         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4307                 set_opt(sb, JOURNAL_DATA);
4308         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4309                 set_opt(sb, ORDERED_DATA);
4310         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4311                 set_opt(sb, WRITEBACK_DATA);
4312
4313         if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_PANIC)
4314                 set_opt(sb, ERRORS_PANIC);
4315         else if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_CONTINUE)
4316                 set_opt(sb, ERRORS_CONT);
4317         else
4318                 set_opt(sb, ERRORS_RO);
4319         /* block_validity enabled by default; disable with noblock_validity */
4320         set_opt(sb, BLOCK_VALIDITY);
4321         if (def_mount_opts & EXT4_DEFM_DISCARD)
4322                 set_opt(sb, DISCARD);
4323
4324         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4325                 set_opt(sb, BARRIER);
4326
4327         /*
4328          * enable delayed allocation by default
4329          * Use -o nodelalloc to turn it off
4330          */
4331         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4332             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4333                 set_opt(sb, DELALLOC);
4334
4335         if (sb->s_blocksize == PAGE_SIZE)
4336                 set_opt(sb, DIOREAD_NOLOCK);
4337 }
4338
4339 static int ext4_handle_clustersize(struct super_block *sb)
4340 {
4341         struct ext4_sb_info *sbi = EXT4_SB(sb);
4342         struct ext4_super_block *es = sbi->s_es;
4343         int clustersize;
4344
4345         /* Handle clustersize */
4346         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4347         if (ext4_has_feature_bigalloc(sb)) {
4348                 if (clustersize < sb->s_blocksize) {
4349                         ext4_msg(sb, KERN_ERR,
4350                                  "cluster size (%d) smaller than "
4351                                  "block size (%lu)", clustersize, sb->s_blocksize);
4352                         return -EINVAL;
4353                 }
4354                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4355                         le32_to_cpu(es->s_log_block_size);
4356                 sbi->s_clusters_per_group =
4357                         le32_to_cpu(es->s_clusters_per_group);
4358                 if (sbi->s_clusters_per_group > sb->s_blocksize * 8) {
4359                         ext4_msg(sb, KERN_ERR,
4360                                  "#clusters per group too big: %lu",
4361                                  sbi->s_clusters_per_group);
4362                         return -EINVAL;
4363                 }
4364                 if (sbi->s_blocks_per_group !=
4365                     (sbi->s_clusters_per_group * (clustersize / sb->s_blocksize))) {
4366                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4367                                  "clusters per group (%lu) inconsistent",
4368                                  sbi->s_blocks_per_group,
4369                                  sbi->s_clusters_per_group);
4370                         return -EINVAL;
4371                 }
4372         } else {
4373                 if (clustersize != sb->s_blocksize) {
4374                         ext4_msg(sb, KERN_ERR,
4375                                  "fragment/cluster size (%d) != "
4376                                  "block size (%lu)", clustersize, sb->s_blocksize);
4377                         return -EINVAL;
4378                 }
4379                 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
4380                         ext4_msg(sb, KERN_ERR,
4381                                  "#blocks per group too big: %lu",
4382                                  sbi->s_blocks_per_group);
4383                         return -EINVAL;
4384                 }
4385                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4386                 sbi->s_cluster_bits = 0;
4387         }
4388         sbi->s_cluster_ratio = clustersize / sb->s_blocksize;
4389
4390         /* Do we have standard group size of clustersize * 8 blocks ? */
4391         if (sbi->s_blocks_per_group == clustersize << 3)
4392                 set_opt2(sb, STD_GROUP_SIZE);
4393
4394         return 0;
4395 }
4396
4397 static void ext4_fast_commit_init(struct super_block *sb)
4398 {
4399         struct ext4_sb_info *sbi = EXT4_SB(sb);
4400
4401         /* Initialize fast commit stuff */
4402         atomic_set(&sbi->s_fc_subtid, 0);
4403         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4404         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4405         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4406         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4407         sbi->s_fc_bytes = 0;
4408         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4409         sbi->s_fc_ineligible_tid = 0;
4410         spin_lock_init(&sbi->s_fc_lock);
4411         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4412         sbi->s_fc_replay_state.fc_regions = NULL;
4413         sbi->s_fc_replay_state.fc_regions_size = 0;
4414         sbi->s_fc_replay_state.fc_regions_used = 0;
4415         sbi->s_fc_replay_state.fc_regions_valid = 0;
4416         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4417         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4418         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4419 }
4420
4421 static int ext4_inode_info_init(struct super_block *sb,
4422                                 struct ext4_super_block *es)
4423 {
4424         struct ext4_sb_info *sbi = EXT4_SB(sb);
4425
4426         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4427                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4428                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4429         } else {
4430                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4431                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4432                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4433                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4434                                  sbi->s_first_ino);
4435                         return -EINVAL;
4436                 }
4437                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4438                     (!is_power_of_2(sbi->s_inode_size)) ||
4439                     (sbi->s_inode_size > sb->s_blocksize)) {
4440                         ext4_msg(sb, KERN_ERR,
4441                                "unsupported inode size: %d",
4442                                sbi->s_inode_size);
4443                         ext4_msg(sb, KERN_ERR, "blocksize: %lu", sb->s_blocksize);
4444                         return -EINVAL;
4445                 }
4446                 /*
4447                  * i_atime_extra is the last extra field available for
4448                  * [acm]times in struct ext4_inode. Checking for that
4449                  * field should suffice to ensure we have extra space
4450                  * for all three.
4451                  */
4452                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4453                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4454                         sb->s_time_gran = 1;
4455                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4456                 } else {
4457                         sb->s_time_gran = NSEC_PER_SEC;
4458                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4459                 }
4460                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4461         }
4462
4463         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4464                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4465                         EXT4_GOOD_OLD_INODE_SIZE;
4466                 if (ext4_has_feature_extra_isize(sb)) {
4467                         unsigned v, max = (sbi->s_inode_size -
4468                                            EXT4_GOOD_OLD_INODE_SIZE);
4469
4470                         v = le16_to_cpu(es->s_want_extra_isize);
4471                         if (v > max) {
4472                                 ext4_msg(sb, KERN_ERR,
4473                                          "bad s_want_extra_isize: %d", v);
4474                                 return -EINVAL;
4475                         }
4476                         if (sbi->s_want_extra_isize < v)
4477                                 sbi->s_want_extra_isize = v;
4478
4479                         v = le16_to_cpu(es->s_min_extra_isize);
4480                         if (v > max) {
4481                                 ext4_msg(sb, KERN_ERR,
4482                                          "bad s_min_extra_isize: %d", v);
4483                                 return -EINVAL;
4484                         }
4485                         if (sbi->s_want_extra_isize < v)
4486                                 sbi->s_want_extra_isize = v;
4487                 }
4488         }
4489
4490         return 0;
4491 }
4492
4493 #if IS_ENABLED(CONFIG_UNICODE)
4494 static int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4495 {
4496         const struct ext4_sb_encodings *encoding_info;
4497         struct unicode_map *encoding;
4498         __u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4499
4500         if (!ext4_has_feature_casefold(sb) || sb->s_encoding)
4501                 return 0;
4502
4503         encoding_info = ext4_sb_read_encoding(es);
4504         if (!encoding_info) {
4505                 ext4_msg(sb, KERN_ERR,
4506                         "Encoding requested by superblock is unknown");
4507                 return -EINVAL;
4508         }
4509
4510         encoding = utf8_load(encoding_info->version);
4511         if (IS_ERR(encoding)) {
4512                 ext4_msg(sb, KERN_ERR,
4513                         "can't mount with superblock charset: %s-%u.%u.%u "
4514                         "not supported by the kernel. flags: 0x%x.",
4515                         encoding_info->name,
4516                         unicode_major(encoding_info->version),
4517                         unicode_minor(encoding_info->version),
4518                         unicode_rev(encoding_info->version),
4519                         encoding_flags);
4520                 return -EINVAL;
4521         }
4522         ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4523                 "%s-%u.%u.%u with flags 0x%hx", encoding_info->name,
4524                 unicode_major(encoding_info->version),
4525                 unicode_minor(encoding_info->version),
4526                 unicode_rev(encoding_info->version),
4527                 encoding_flags);
4528
4529         sb->s_encoding = encoding;
4530         sb->s_encoding_flags = encoding_flags;
4531
4532         return 0;
4533 }
4534 #else
4535 static inline int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4536 {
4537         return 0;
4538 }
4539 #endif
4540
4541 static int ext4_init_metadata_csum(struct super_block *sb, struct ext4_super_block *es)
4542 {
4543         struct ext4_sb_info *sbi = EXT4_SB(sb);
4544
4545         /* Warn if metadata_csum and gdt_csum are both set. */
4546         if (ext4_has_feature_metadata_csum(sb) &&
4547             ext4_has_feature_gdt_csum(sb))
4548                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4549                              "redundant flags; please run fsck.");
4550
4551         /* Check for a known checksum algorithm */
4552         if (!ext4_verify_csum_type(sb, es)) {
4553                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4554                          "unknown checksum algorithm.");
4555                 return -EINVAL;
4556         }
4557         ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4558                                 ext4_orphan_file_block_trigger);
4559
4560         /* Load the checksum driver */
4561         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4562         if (IS_ERR(sbi->s_chksum_driver)) {
4563                 int ret = PTR_ERR(sbi->s_chksum_driver);
4564                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4565                 sbi->s_chksum_driver = NULL;
4566                 return ret;
4567         }
4568
4569         /* Check superblock checksum */
4570         if (!ext4_superblock_csum_verify(sb, es)) {
4571                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4572                          "invalid superblock checksum.  Run e2fsck?");
4573                 return -EFSBADCRC;
4574         }
4575
4576         /* Precompute checksum seed for all metadata */
4577         if (ext4_has_feature_csum_seed(sb))
4578                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4579         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4580                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4581                                                sizeof(es->s_uuid));
4582         return 0;
4583 }
4584
4585 static int ext4_check_feature_compatibility(struct super_block *sb,
4586                                             struct ext4_super_block *es,
4587                                             int silent)
4588 {
4589         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4590             (ext4_has_compat_features(sb) ||
4591              ext4_has_ro_compat_features(sb) ||
4592              ext4_has_incompat_features(sb)))
4593                 ext4_msg(sb, KERN_WARNING,
4594                        "feature flags set on rev 0 fs, "
4595                        "running e2fsck is recommended");
4596
4597         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4598                 set_opt2(sb, HURD_COMPAT);
4599                 if (ext4_has_feature_64bit(sb)) {
4600                         ext4_msg(sb, KERN_ERR,
4601                                  "The Hurd can't support 64-bit file systems");
4602                         return -EINVAL;
4603                 }
4604
4605                 /*
4606                  * ea_inode feature uses l_i_version field which is not
4607                  * available in HURD_COMPAT mode.
4608                  */
4609                 if (ext4_has_feature_ea_inode(sb)) {
4610                         ext4_msg(sb, KERN_ERR,
4611                                  "ea_inode feature is not supported for Hurd");
4612                         return -EINVAL;
4613                 }
4614         }
4615
4616         if (IS_EXT2_SB(sb)) {
4617                 if (ext2_feature_set_ok(sb))
4618                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4619                                  "using the ext4 subsystem");
4620                 else {
4621                         /*
4622                          * If we're probing be silent, if this looks like
4623                          * it's actually an ext[34] filesystem.
4624                          */
4625                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4626                                 return -EINVAL;
4627                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4628                                  "to feature incompatibilities");
4629                         return -EINVAL;
4630                 }
4631         }
4632
4633         if (IS_EXT3_SB(sb)) {
4634                 if (ext3_feature_set_ok(sb))
4635                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4636                                  "using the ext4 subsystem");
4637                 else {
4638                         /*
4639                          * If we're probing be silent, if this looks like
4640                          * it's actually an ext4 filesystem.
4641                          */
4642                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4643                                 return -EINVAL;
4644                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4645                                  "to feature incompatibilities");
4646                         return -EINVAL;
4647                 }
4648         }
4649
4650         /*
4651          * Check feature flags regardless of the revision level, since we
4652          * previously didn't change the revision level when setting the flags,
4653          * so there is a chance incompat flags are set on a rev 0 filesystem.
4654          */
4655         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4656                 return -EINVAL;
4657
4658         return 0;
4659 }
4660
4661 static int ext4_geometry_check(struct super_block *sb,
4662                                struct ext4_super_block *es)
4663 {
4664         struct ext4_sb_info *sbi = EXT4_SB(sb);
4665         __u64 blocks_count;
4666
4667         /* check blocks count against device size */
4668         blocks_count = sb_bdev_nr_blocks(sb);
4669         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4670                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4671                        "exceeds size of device (%llu blocks)",
4672                        ext4_blocks_count(es), blocks_count);
4673                 return -EINVAL;
4674         }
4675
4676         /*
4677          * It makes no sense for the first data block to be beyond the end
4678          * of the filesystem.
4679          */
4680         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4681                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4682                          "block %u is beyond end of filesystem (%llu)",
4683                          le32_to_cpu(es->s_first_data_block),
4684                          ext4_blocks_count(es));
4685                 return -EINVAL;
4686         }
4687         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4688             (sbi->s_cluster_ratio == 1)) {
4689                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4690                          "block is 0 with a 1k block and cluster size");
4691                 return -EINVAL;
4692         }
4693
4694         blocks_count = (ext4_blocks_count(es) -
4695                         le32_to_cpu(es->s_first_data_block) +
4696                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4697         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4698         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4699                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4700                        "(block count %llu, first data block %u, "
4701                        "blocks per group %lu)", blocks_count,
4702                        ext4_blocks_count(es),
4703                        le32_to_cpu(es->s_first_data_block),
4704                        EXT4_BLOCKS_PER_GROUP(sb));
4705                 return -EINVAL;
4706         }
4707         sbi->s_groups_count = blocks_count;
4708         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4709                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4710         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4711             le32_to_cpu(es->s_inodes_count)) {
4712                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4713                          le32_to_cpu(es->s_inodes_count),
4714                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4715                 return -EINVAL;
4716         }
4717
4718         return 0;
4719 }
4720
4721 static void ext4_group_desc_free(struct ext4_sb_info *sbi)
4722 {
4723         struct buffer_head **group_desc;
4724         int i;
4725
4726         rcu_read_lock();
4727         group_desc = rcu_dereference(sbi->s_group_desc);
4728         for (i = 0; i < sbi->s_gdb_count; i++)
4729                 brelse(group_desc[i]);
4730         kvfree(group_desc);
4731         rcu_read_unlock();
4732 }
4733
4734 static int ext4_group_desc_init(struct super_block *sb,
4735                                 struct ext4_super_block *es,
4736                                 ext4_fsblk_t logical_sb_block,
4737                                 ext4_group_t *first_not_zeroed)
4738 {
4739         struct ext4_sb_info *sbi = EXT4_SB(sb);
4740         unsigned int db_count;
4741         ext4_fsblk_t block;
4742         int ret;
4743         int i;
4744
4745         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4746                    EXT4_DESC_PER_BLOCK(sb);
4747         if (ext4_has_feature_meta_bg(sb)) {
4748                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4749                         ext4_msg(sb, KERN_WARNING,
4750                                  "first meta block group too large: %u "
4751                                  "(group descriptor block count %u)",
4752                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4753                         return -EINVAL;
4754                 }
4755         }
4756         rcu_assign_pointer(sbi->s_group_desc,
4757                            kvmalloc_array(db_count,
4758                                           sizeof(struct buffer_head *),
4759                                           GFP_KERNEL));
4760         if (sbi->s_group_desc == NULL) {
4761                 ext4_msg(sb, KERN_ERR, "not enough memory");
4762                 return -ENOMEM;
4763         }
4764
4765         bgl_lock_init(sbi->s_blockgroup_lock);
4766
4767         /* Pre-read the descriptors into the buffer cache */
4768         for (i = 0; i < db_count; i++) {
4769                 block = descriptor_loc(sb, logical_sb_block, i);
4770                 ext4_sb_breadahead_unmovable(sb, block);
4771         }
4772
4773         for (i = 0; i < db_count; i++) {
4774                 struct buffer_head *bh;
4775
4776                 block = descriptor_loc(sb, logical_sb_block, i);
4777                 bh = ext4_sb_bread_unmovable(sb, block);
4778                 if (IS_ERR(bh)) {
4779                         ext4_msg(sb, KERN_ERR,
4780                                "can't read group descriptor %d", i);
4781                         sbi->s_gdb_count = i;
4782                         ret = PTR_ERR(bh);
4783                         goto out;
4784                 }
4785                 rcu_read_lock();
4786                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4787                 rcu_read_unlock();
4788         }
4789         sbi->s_gdb_count = db_count;
4790         if (!ext4_check_descriptors(sb, logical_sb_block, first_not_zeroed)) {
4791                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4792                 ret = -EFSCORRUPTED;
4793                 goto out;
4794         }
4795         return 0;
4796 out:
4797         ext4_group_desc_free(sbi);
4798         return ret;
4799 }
4800
4801 static int ext4_load_and_init_journal(struct super_block *sb,
4802                                       struct ext4_super_block *es,
4803                                       struct ext4_fs_context *ctx)
4804 {
4805         struct ext4_sb_info *sbi = EXT4_SB(sb);
4806         int err;
4807
4808         err = ext4_load_journal(sb, es, ctx->journal_devnum);
4809         if (err)
4810                 return err;
4811
4812         if (ext4_has_feature_64bit(sb) &&
4813             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4814                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4815                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4816                 goto out;
4817         }
4818
4819         if (!set_journal_csum_feature_set(sb)) {
4820                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4821                          "feature set");
4822                 goto out;
4823         }
4824
4825         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4826                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4827                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4828                 ext4_msg(sb, KERN_ERR,
4829                         "Failed to set fast commit journal feature");
4830                 goto out;
4831         }
4832
4833         /* We have now updated the journal if required, so we can
4834          * validate the data journaling mode. */
4835         switch (test_opt(sb, DATA_FLAGS)) {
4836         case 0:
4837                 /* No mode set, assume a default based on the journal
4838                  * capabilities: ORDERED_DATA if the journal can
4839                  * cope, else JOURNAL_DATA
4840                  */
4841                 if (jbd2_journal_check_available_features
4842                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4843                         set_opt(sb, ORDERED_DATA);
4844                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4845                 } else {
4846                         set_opt(sb, JOURNAL_DATA);
4847                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4848                 }
4849                 break;
4850
4851         case EXT4_MOUNT_ORDERED_DATA:
4852         case EXT4_MOUNT_WRITEBACK_DATA:
4853                 if (!jbd2_journal_check_available_features
4854                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4855                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4856                                "requested data journaling mode");
4857                         goto out;
4858                 }
4859                 break;
4860         default:
4861                 break;
4862         }
4863
4864         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4865             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4866                 ext4_msg(sb, KERN_ERR, "can't mount with "
4867                         "journal_async_commit in data=ordered mode");
4868                 goto out;
4869         }
4870
4871         set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
4872
4873         sbi->s_journal->j_submit_inode_data_buffers =
4874                 ext4_journal_submit_inode_data_buffers;
4875         sbi->s_journal->j_finish_inode_data_buffers =
4876                 ext4_journal_finish_inode_data_buffers;
4877
4878         return 0;
4879
4880 out:
4881         /* flush s_error_work before journal destroy. */
4882         flush_work(&sbi->s_error_work);
4883         jbd2_journal_destroy(sbi->s_journal);
4884         sbi->s_journal = NULL;
4885         return -EINVAL;
4886 }
4887
4888 static int ext4_journal_data_mode_check(struct super_block *sb)
4889 {
4890         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4891                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with "
4892                             "data=journal disables delayed allocation, "
4893                             "dioread_nolock, O_DIRECT and fast_commit support!\n");
4894                 /* can't mount with both data=journal and dioread_nolock. */
4895                 clear_opt(sb, DIOREAD_NOLOCK);
4896                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4897                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4898                         ext4_msg(sb, KERN_ERR, "can't mount with "
4899                                  "both data=journal and delalloc");
4900                         return -EINVAL;
4901                 }
4902                 if (test_opt(sb, DAX_ALWAYS)) {
4903                         ext4_msg(sb, KERN_ERR, "can't mount with "
4904                                  "both data=journal and dax");
4905                         return -EINVAL;
4906                 }
4907                 if (ext4_has_feature_encrypt(sb)) {
4908                         ext4_msg(sb, KERN_WARNING,
4909                                  "encrypted files will use data=ordered "
4910                                  "instead of data journaling mode");
4911                 }
4912                 if (test_opt(sb, DELALLOC))
4913                         clear_opt(sb, DELALLOC);
4914         } else {
4915                 sb->s_iflags |= SB_I_CGROUPWB;
4916         }
4917
4918         return 0;
4919 }
4920
4921 static int ext4_load_super(struct super_block *sb, ext4_fsblk_t *lsb,
4922                            int silent)
4923 {
4924         struct ext4_sb_info *sbi = EXT4_SB(sb);
4925         struct ext4_super_block *es;
4926         ext4_fsblk_t logical_sb_block;
4927         unsigned long offset = 0;
4928         struct buffer_head *bh;
4929         int ret = -EINVAL;
4930         int blocksize;
4931
4932         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4933         if (!blocksize) {
4934                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4935                 return -EINVAL;
4936         }
4937
4938         /*
4939          * The ext4 superblock will not be buffer aligned for other than 1kB
4940          * block sizes.  We need to calculate the offset from buffer start.
4941          */
4942         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4943                 logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
4944                 offset = do_div(logical_sb_block, blocksize);
4945         } else {
4946                 logical_sb_block = sbi->s_sb_block;
4947         }
4948
4949         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4950         if (IS_ERR(bh)) {
4951                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4952                 return PTR_ERR(bh);
4953         }
4954         /*
4955          * Note: s_es must be initialized as soon as possible because
4956          *       some ext4 macro-instructions depend on its value
4957          */
4958         es = (struct ext4_super_block *) (bh->b_data + offset);
4959         sbi->s_es = es;
4960         sb->s_magic = le16_to_cpu(es->s_magic);
4961         if (sb->s_magic != EXT4_SUPER_MAGIC) {
4962                 if (!silent)
4963                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4964                 goto out;
4965         }
4966
4967         if (le32_to_cpu(es->s_log_block_size) >
4968             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4969                 ext4_msg(sb, KERN_ERR,
4970                          "Invalid log block size: %u",
4971                          le32_to_cpu(es->s_log_block_size));
4972                 goto out;
4973         }
4974         if (le32_to_cpu(es->s_log_cluster_size) >
4975             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4976                 ext4_msg(sb, KERN_ERR,
4977                          "Invalid log cluster size: %u",
4978                          le32_to_cpu(es->s_log_cluster_size));
4979                 goto out;
4980         }
4981
4982         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4983
4984         /*
4985          * If the default block size is not the same as the real block size,
4986          * we need to reload it.
4987          */
4988         if (sb->s_blocksize == blocksize) {
4989                 *lsb = logical_sb_block;
4990                 sbi->s_sbh = bh;
4991                 return 0;
4992         }
4993
4994         /*
4995          * bh must be released before kill_bdev(), otherwise
4996          * it won't be freed and its page also. kill_bdev()
4997          * is called by sb_set_blocksize().
4998          */
4999         brelse(bh);
5000         /* Validate the filesystem blocksize */
5001         if (!sb_set_blocksize(sb, blocksize)) {
5002                 ext4_msg(sb, KERN_ERR, "bad block size %d",
5003                                 blocksize);
5004                 bh = NULL;
5005                 goto out;
5006         }
5007
5008         logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5009         offset = do_div(logical_sb_block, blocksize);
5010         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5011         if (IS_ERR(bh)) {
5012                 ext4_msg(sb, KERN_ERR, "Can't read superblock on 2nd try");
5013                 ret = PTR_ERR(bh);
5014                 bh = NULL;
5015                 goto out;
5016         }
5017         es = (struct ext4_super_block *)(bh->b_data + offset);
5018         sbi->s_es = es;
5019         if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
5020                 ext4_msg(sb, KERN_ERR, "Magic mismatch, very weird!");
5021                 goto out;
5022         }
5023         *lsb = logical_sb_block;
5024         sbi->s_sbh = bh;
5025         return 0;
5026 out:
5027         brelse(bh);
5028         return ret;
5029 }
5030
5031 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
5032 {
5033         struct ext4_super_block *es = NULL;
5034         struct ext4_sb_info *sbi = EXT4_SB(sb);
5035         struct flex_groups **flex_groups;
5036         ext4_fsblk_t block;
5037         ext4_fsblk_t logical_sb_block;
5038         struct inode *root;
5039         int ret = -ENOMEM;
5040         unsigned int i;
5041         int needs_recovery, has_huge_files;
5042         int err = 0;
5043         ext4_group_t first_not_zeroed;
5044         struct ext4_fs_context *ctx = fc->fs_private;
5045         int silent = fc->sb_flags & SB_SILENT;
5046
5047         /* Set defaults for the variables that will be set during parsing */
5048         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO))
5049                 ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5050
5051         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
5052         sbi->s_sectors_written_start =
5053                 part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
5054
5055         /* -EINVAL is default */
5056         ret = -EINVAL;
5057         err = ext4_load_super(sb, &logical_sb_block, silent);
5058         if (err)
5059                 goto out_fail;
5060
5061         es = sbi->s_es;
5062         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
5063
5064         err = ext4_init_metadata_csum(sb, es);
5065         if (err)
5066                 goto failed_mount;
5067
5068         ext4_set_def_opts(sb, es);
5069
5070         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
5071         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
5072         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
5073         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
5074         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
5075
5076         /*
5077          * set default s_li_wait_mult for lazyinit, for the case there is
5078          * no mount option specified.
5079          */
5080         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
5081
5082         if (ext4_inode_info_init(sb, es))
5083                 goto failed_mount;
5084
5085         err = parse_apply_sb_mount_options(sb, ctx);
5086         if (err < 0)
5087                 goto failed_mount;
5088
5089         sbi->s_def_mount_opt = sbi->s_mount_opt;
5090
5091         err = ext4_check_opt_consistency(fc, sb);
5092         if (err < 0)
5093                 goto failed_mount;
5094
5095         ext4_apply_options(fc, sb);
5096
5097         if (ext4_encoding_init(sb, es))
5098                 goto failed_mount;
5099
5100         if (ext4_journal_data_mode_check(sb))
5101                 goto failed_mount;
5102
5103         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5104                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5105
5106         /* i_version is always enabled now */
5107         sb->s_flags |= SB_I_VERSION;
5108
5109         if (ext4_check_feature_compatibility(sb, es, silent))
5110                 goto failed_mount;
5111
5112         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (sb->s_blocksize / 4)) {
5113                 ext4_msg(sb, KERN_ERR,
5114                          "Number of reserved GDT blocks insanely large: %d",
5115                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
5116                 goto failed_mount;
5117         }
5118
5119         if (sbi->s_daxdev) {
5120                 if (sb->s_blocksize == PAGE_SIZE)
5121                         set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
5122                 else
5123                         ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
5124         }
5125
5126         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
5127                 if (ext4_has_feature_inline_data(sb)) {
5128                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
5129                                         " that may contain inline data");
5130                         goto failed_mount;
5131                 }
5132                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
5133                         ext4_msg(sb, KERN_ERR,
5134                                 "DAX unsupported by block device.");
5135                         goto failed_mount;
5136                 }
5137         }
5138
5139         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
5140                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
5141                          es->s_encryption_level);
5142                 goto failed_mount;
5143         }
5144
5145         has_huge_files = ext4_has_feature_huge_file(sb);
5146         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
5147                                                       has_huge_files);
5148         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
5149
5150         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
5151         if (ext4_has_feature_64bit(sb)) {
5152                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
5153                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
5154                     !is_power_of_2(sbi->s_desc_size)) {
5155                         ext4_msg(sb, KERN_ERR,
5156                                "unsupported descriptor size %lu",
5157                                sbi->s_desc_size);
5158                         goto failed_mount;
5159                 }
5160         } else
5161                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
5162
5163         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
5164         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
5165
5166         sbi->s_inodes_per_block = sb->s_blocksize / EXT4_INODE_SIZE(sb);
5167         if (sbi->s_inodes_per_block == 0 || sbi->s_blocks_per_group == 0) {
5168                 if (!silent)
5169                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5170                 goto failed_mount;
5171         }
5172         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
5173             sbi->s_inodes_per_group > sb->s_blocksize * 8) {
5174                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
5175                          sbi->s_inodes_per_group);
5176                 goto failed_mount;
5177         }
5178         sbi->s_itb_per_group = sbi->s_inodes_per_group /
5179                                         sbi->s_inodes_per_block;
5180         sbi->s_desc_per_block = sb->s_blocksize / EXT4_DESC_SIZE(sb);
5181         sbi->s_mount_state = le16_to_cpu(es->s_state) & ~EXT4_FC_REPLAY;
5182         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
5183         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
5184
5185         for (i = 0; i < 4; i++)
5186                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
5187         sbi->s_def_hash_version = es->s_def_hash_version;
5188         if (ext4_has_feature_dir_index(sb)) {
5189                 i = le32_to_cpu(es->s_flags);
5190                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
5191                         sbi->s_hash_unsigned = 3;
5192                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
5193 #ifdef __CHAR_UNSIGNED__
5194                         if (!sb_rdonly(sb))
5195                                 es->s_flags |=
5196                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
5197                         sbi->s_hash_unsigned = 3;
5198 #else
5199                         if (!sb_rdonly(sb))
5200                                 es->s_flags |=
5201                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
5202 #endif
5203                 }
5204         }
5205
5206         if (ext4_handle_clustersize(sb))
5207                 goto failed_mount;
5208
5209         /*
5210          * Test whether we have more sectors than will fit in sector_t,
5211          * and whether the max offset is addressable by the page cache.
5212          */
5213         err = generic_check_addressable(sb->s_blocksize_bits,
5214                                         ext4_blocks_count(es));
5215         if (err) {
5216                 ext4_msg(sb, KERN_ERR, "filesystem"
5217                          " too large to mount safely on this system");
5218                 goto failed_mount;
5219         }
5220
5221         if (ext4_geometry_check(sb, es))
5222                 goto failed_mount;
5223
5224         err = ext4_group_desc_init(sb, es, logical_sb_block, &first_not_zeroed);
5225         if (err)
5226                 goto failed_mount;
5227
5228         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5229         spin_lock_init(&sbi->s_error_lock);
5230         INIT_WORK(&sbi->s_error_work, flush_stashed_error_work);
5231
5232         /* Register extent status tree shrinker */
5233         if (ext4_es_register_shrinker(sbi))
5234                 goto failed_mount3;
5235
5236         sbi->s_stripe = ext4_get_stripe_size(sbi);
5237         sbi->s_extent_max_zeroout_kb = 32;
5238
5239         /*
5240          * set up enough so that it can read an inode
5241          */
5242         sb->s_op = &ext4_sops;
5243         sb->s_export_op = &ext4_export_ops;
5244         sb->s_xattr = ext4_xattr_handlers;
5245 #ifdef CONFIG_FS_ENCRYPTION
5246         sb->s_cop = &ext4_cryptops;
5247 #endif
5248 #ifdef CONFIG_FS_VERITY
5249         sb->s_vop = &ext4_verityops;
5250 #endif
5251 #ifdef CONFIG_QUOTA
5252         sb->dq_op = &ext4_quota_operations;
5253         if (ext4_has_feature_quota(sb))
5254                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
5255         else
5256                 sb->s_qcop = &ext4_qctl_operations;
5257         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5258 #endif
5259         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
5260
5261         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5262         mutex_init(&sbi->s_orphan_lock);
5263
5264         ext4_fast_commit_init(sb);
5265
5266         sb->s_root = NULL;
5267
5268         needs_recovery = (es->s_last_orphan != 0 ||
5269                           ext4_has_feature_orphan_present(sb) ||
5270                           ext4_has_feature_journal_needs_recovery(sb));
5271
5272         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
5273                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
5274                         goto failed_mount3a;
5275
5276         /*
5277          * The first inode we look at is the journal inode.  Don't try
5278          * root first: it may be modified in the journal!
5279          */
5280         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5281                 err = ext4_load_and_init_journal(sb, es, ctx);
5282                 if (err)
5283                         goto failed_mount3a;
5284         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5285                    ext4_has_feature_journal_needs_recovery(sb)) {
5286                 ext4_msg(sb, KERN_ERR, "required journal recovery "
5287                        "suppressed and not mounted read-only");
5288                 goto failed_mount3a;
5289         } else {
5290                 /* Nojournal mode, all journal mount options are illegal */
5291                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5292                         ext4_msg(sb, KERN_ERR, "can't mount with "
5293                                  "journal_async_commit, fs mounted w/o journal");
5294                         goto failed_mount3a;
5295                 }
5296
5297                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
5298                         ext4_msg(sb, KERN_ERR, "can't mount with "
5299                                  "journal_checksum, fs mounted w/o journal");
5300                         goto failed_mount3a;
5301                 }
5302                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
5303                         ext4_msg(sb, KERN_ERR, "can't mount with "
5304                                  "commit=%lu, fs mounted w/o journal",
5305                                  sbi->s_commit_interval / HZ);
5306                         goto failed_mount3a;
5307                 }
5308                 if (EXT4_MOUNT_DATA_FLAGS &
5309                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
5310                         ext4_msg(sb, KERN_ERR, "can't mount with "
5311                                  "data=, fs mounted w/o journal");
5312                         goto failed_mount3a;
5313                 }
5314                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5315                 clear_opt(sb, JOURNAL_CHECKSUM);
5316                 clear_opt(sb, DATA_FLAGS);
5317                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
5318                 sbi->s_journal = NULL;
5319                 needs_recovery = 0;
5320         }
5321
5322         if (!test_opt(sb, NO_MBCACHE)) {
5323                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
5324                 if (!sbi->s_ea_block_cache) {
5325                         ext4_msg(sb, KERN_ERR,
5326                                  "Failed to create ea_block_cache");
5327                         goto failed_mount_wq;
5328                 }
5329
5330                 if (ext4_has_feature_ea_inode(sb)) {
5331                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5332                         if (!sbi->s_ea_inode_cache) {
5333                                 ext4_msg(sb, KERN_ERR,
5334                                          "Failed to create ea_inode_cache");
5335                                 goto failed_mount_wq;
5336                         }
5337                 }
5338         }
5339
5340         if (ext4_has_feature_verity(sb) && sb->s_blocksize != PAGE_SIZE) {
5341                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
5342                 goto failed_mount_wq;
5343         }
5344
5345         /*
5346          * Get the # of file system overhead blocks from the
5347          * superblock if present.
5348          */
5349         sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5350         /* ignore the precalculated value if it is ridiculous */
5351         if (sbi->s_overhead > ext4_blocks_count(es))
5352                 sbi->s_overhead = 0;
5353         /*
5354          * If the bigalloc feature is not enabled recalculating the
5355          * overhead doesn't take long, so we might as well just redo
5356          * it to make sure we are using the correct value.
5357          */
5358         if (!ext4_has_feature_bigalloc(sb))
5359                 sbi->s_overhead = 0;
5360         if (sbi->s_overhead == 0) {
5361                 err = ext4_calculate_overhead(sb);
5362                 if (err)
5363                         goto failed_mount_wq;
5364         }
5365
5366         /*
5367          * The maximum number of concurrent works can be high and
5368          * concurrency isn't really necessary.  Limit it to 1.
5369          */
5370         EXT4_SB(sb)->rsv_conversion_wq =
5371                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5372         if (!EXT4_SB(sb)->rsv_conversion_wq) {
5373                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5374                 ret = -ENOMEM;
5375                 goto failed_mount4;
5376         }
5377
5378         /*
5379          * The jbd2_journal_load will have done any necessary log recovery,
5380          * so we can safely mount the rest of the filesystem now.
5381          */
5382
5383         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5384         if (IS_ERR(root)) {
5385                 ext4_msg(sb, KERN_ERR, "get root inode failed");
5386                 ret = PTR_ERR(root);
5387                 root = NULL;
5388                 goto failed_mount4;
5389         }
5390         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5391                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5392                 iput(root);
5393                 goto failed_mount4;
5394         }
5395
5396         sb->s_root = d_make_root(root);
5397         if (!sb->s_root) {
5398                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
5399                 ret = -ENOMEM;
5400                 goto failed_mount4;
5401         }
5402
5403         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
5404         if (ret == -EROFS) {
5405                 sb->s_flags |= SB_RDONLY;
5406                 ret = 0;
5407         } else if (ret)
5408                 goto failed_mount4a;
5409
5410         ext4_set_resv_clusters(sb);
5411
5412         if (test_opt(sb, BLOCK_VALIDITY)) {
5413                 err = ext4_setup_system_zone(sb);
5414                 if (err) {
5415                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
5416                                  "zone (%d)", err);
5417                         goto failed_mount4a;
5418                 }
5419         }
5420         ext4_fc_replay_cleanup(sb);
5421
5422         ext4_ext_init(sb);
5423
5424         /*
5425          * Enable optimize_scan if number of groups is > threshold. This can be
5426          * turned off by passing "mb_optimize_scan=0". This can also be
5427          * turned on forcefully by passing "mb_optimize_scan=1".
5428          */
5429         if (!(ctx->spec & EXT4_SPEC_mb_optimize_scan)) {
5430                 if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5431                         set_opt2(sb, MB_OPTIMIZE_SCAN);
5432                 else
5433                         clear_opt2(sb, MB_OPTIMIZE_SCAN);
5434         }
5435
5436         err = ext4_mb_init(sb);
5437         if (err) {
5438                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5439                          err);
5440                 goto failed_mount5;
5441         }
5442
5443         /*
5444          * We can only set up the journal commit callback once
5445          * mballoc is initialized
5446          */
5447         if (sbi->s_journal)
5448                 sbi->s_journal->j_commit_callback =
5449                         ext4_journal_commit_callback;
5450
5451         block = ext4_count_free_clusters(sb);
5452         ext4_free_blocks_count_set(sbi->s_es,
5453                                    EXT4_C2B(sbi, block));
5454         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
5455                                   GFP_KERNEL);
5456         if (!err) {
5457                 unsigned long freei = ext4_count_free_inodes(sb);
5458                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
5459                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
5460                                           GFP_KERNEL);
5461         }
5462         if (!err)
5463                 err = percpu_counter_init(&sbi->s_dirs_counter,
5464                                           ext4_count_dirs(sb), GFP_KERNEL);
5465         if (!err)
5466                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5467                                           GFP_KERNEL);
5468         if (!err)
5469                 err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
5470                                           GFP_KERNEL);
5471         if (!err)
5472                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5473
5474         if (err) {
5475                 ext4_msg(sb, KERN_ERR, "insufficient memory");
5476                 goto failed_mount6;
5477         }
5478
5479         if (ext4_has_feature_flex_bg(sb))
5480                 if (!ext4_fill_flex_info(sb)) {
5481                         ext4_msg(sb, KERN_ERR,
5482                                "unable to initialize "
5483                                "flex_bg meta info!");
5484                         ret = -ENOMEM;
5485                         goto failed_mount6;
5486                 }
5487
5488         err = ext4_register_li_request(sb, first_not_zeroed);
5489         if (err)
5490                 goto failed_mount6;
5491
5492         err = ext4_register_sysfs(sb);
5493         if (err)
5494                 goto failed_mount7;
5495
5496         err = ext4_init_orphan_info(sb);
5497         if (err)
5498                 goto failed_mount8;
5499 #ifdef CONFIG_QUOTA
5500         /* Enable quota usage during mount. */
5501         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5502                 err = ext4_enable_quotas(sb);
5503                 if (err)
5504                         goto failed_mount9;
5505         }
5506 #endif  /* CONFIG_QUOTA */
5507
5508         /*
5509          * Save the original bdev mapping's wb_err value which could be
5510          * used to detect the metadata async write error.
5511          */
5512         spin_lock_init(&sbi->s_bdev_wb_lock);
5513         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5514                                  &sbi->s_bdev_wb_err);
5515         sb->s_bdev->bd_super = sb;
5516         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5517         ext4_orphan_cleanup(sb, es);
5518         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5519         /*
5520          * Update the checksum after updating free space/inode counters and
5521          * ext4_orphan_cleanup. Otherwise the superblock can have an incorrect
5522          * checksum in the buffer cache until it is written out and
5523          * e2fsprogs programs trying to open a file system immediately
5524          * after it is mounted can fail.
5525          */
5526         ext4_superblock_csum_set(sb);
5527         if (needs_recovery) {
5528                 ext4_msg(sb, KERN_INFO, "recovery complete");
5529                 err = ext4_mark_recovery_complete(sb, es);
5530                 if (err)
5531                         goto failed_mount9;
5532         }
5533
5534         if (test_opt(sb, DISCARD) && !bdev_max_discard_sectors(sb->s_bdev))
5535                 ext4_msg(sb, KERN_WARNING,
5536                          "mounting with \"discard\" option, but the device does not support discard");
5537
5538         if (es->s_error_count)
5539                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5540
5541         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5542         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5543         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5544         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5545         atomic_set(&sbi->s_warning_count, 0);
5546         atomic_set(&sbi->s_msg_count, 0);
5547
5548         return 0;
5549
5550 failed_mount9:
5551         ext4_release_orphan_info(sb);
5552 failed_mount8:
5553         ext4_unregister_sysfs(sb);
5554         kobject_put(&sbi->s_kobj);
5555 failed_mount7:
5556         ext4_unregister_li_request(sb);
5557 failed_mount6:
5558         ext4_mb_release(sb);
5559         rcu_read_lock();
5560         flex_groups = rcu_dereference(sbi->s_flex_groups);
5561         if (flex_groups) {
5562                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5563                         kvfree(flex_groups[i]);
5564                 kvfree(flex_groups);
5565         }
5566         rcu_read_unlock();
5567         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5568         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5569         percpu_counter_destroy(&sbi->s_dirs_counter);
5570         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5571         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
5572         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5573 failed_mount5:
5574         ext4_ext_release(sb);
5575         ext4_release_system_zone(sb);
5576 failed_mount4a:
5577         dput(sb->s_root);
5578         sb->s_root = NULL;
5579 failed_mount4:
5580         ext4_msg(sb, KERN_ERR, "mount failed");
5581         if (EXT4_SB(sb)->rsv_conversion_wq)
5582                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5583 failed_mount_wq:
5584         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5585         sbi->s_ea_inode_cache = NULL;
5586
5587         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5588         sbi->s_ea_block_cache = NULL;
5589
5590         if (sbi->s_journal) {
5591                 /* flush s_error_work before journal destroy. */
5592                 flush_work(&sbi->s_error_work);
5593                 jbd2_journal_destroy(sbi->s_journal);
5594                 sbi->s_journal = NULL;
5595         }
5596 failed_mount3a:
5597         ext4_es_unregister_shrinker(sbi);
5598 failed_mount3:
5599         /* flush s_error_work before sbi destroy */
5600         flush_work(&sbi->s_error_work);
5601         del_timer_sync(&sbi->s_err_report);
5602         ext4_stop_mmpd(sbi);
5603         ext4_group_desc_free(sbi);
5604 failed_mount:
5605         if (sbi->s_chksum_driver)
5606                 crypto_free_shash(sbi->s_chksum_driver);
5607
5608 #if IS_ENABLED(CONFIG_UNICODE)
5609         utf8_unload(sb->s_encoding);
5610 #endif
5611
5612 #ifdef CONFIG_QUOTA
5613         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5614                 kfree(get_qf_name(sb, sbi, i));
5615 #endif
5616         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5617         /* ext4_blkdev_remove() calls kill_bdev(), release bh before it. */
5618         brelse(sbi->s_sbh);
5619         ext4_blkdev_remove(sbi);
5620 out_fail:
5621         sb->s_fs_info = NULL;
5622         return err ? err : ret;
5623 }
5624
5625 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5626 {
5627         struct ext4_fs_context *ctx = fc->fs_private;
5628         struct ext4_sb_info *sbi;
5629         const char *descr;
5630         int ret;
5631
5632         sbi = ext4_alloc_sbi(sb);
5633         if (!sbi)
5634                 return -ENOMEM;
5635
5636         fc->s_fs_info = sbi;
5637
5638         /* Cleanup superblock name */
5639         strreplace(sb->s_id, '/', '!');
5640
5641         sbi->s_sb_block = 1;    /* Default super block location */
5642         if (ctx->spec & EXT4_SPEC_s_sb_block)
5643                 sbi->s_sb_block = ctx->s_sb_block;
5644
5645         ret = __ext4_fill_super(fc, sb);
5646         if (ret < 0)
5647                 goto free_sbi;
5648
5649         if (sbi->s_journal) {
5650                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5651                         descr = " journalled data mode";
5652                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5653                         descr = " ordered data mode";
5654                 else
5655                         descr = " writeback data mode";
5656         } else
5657                 descr = "out journal";
5658
5659         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5660                 ext4_msg(sb, KERN_INFO, "mounted filesystem %pU with%s. "
5661                          "Quota mode: %s.", &sb->s_uuid, descr,
5662                          ext4_quota_mode(sb));
5663
5664         /* Update the s_overhead_clusters if necessary */
5665         ext4_update_overhead(sb, false);
5666         return 0;
5667
5668 free_sbi:
5669         ext4_free_sbi(sbi);
5670         fc->s_fs_info = NULL;
5671         return ret;
5672 }
5673
5674 static int ext4_get_tree(struct fs_context *fc)
5675 {
5676         return get_tree_bdev(fc, ext4_fill_super);
5677 }
5678
5679 /*
5680  * Setup any per-fs journal parameters now.  We'll do this both on
5681  * initial mount, once the journal has been initialised but before we've
5682  * done any recovery; and again on any subsequent remount.
5683  */
5684 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5685 {
5686         struct ext4_sb_info *sbi = EXT4_SB(sb);
5687
5688         journal->j_commit_interval = sbi->s_commit_interval;
5689         journal->j_min_batch_time = sbi->s_min_batch_time;
5690         journal->j_max_batch_time = sbi->s_max_batch_time;
5691         ext4_fc_init(sb, journal);
5692
5693         write_lock(&journal->j_state_lock);
5694         if (test_opt(sb, BARRIER))
5695                 journal->j_flags |= JBD2_BARRIER;
5696         else
5697                 journal->j_flags &= ~JBD2_BARRIER;
5698         if (test_opt(sb, DATA_ERR_ABORT))
5699                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5700         else
5701                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5702         write_unlock(&journal->j_state_lock);
5703 }
5704
5705 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5706                                              unsigned int journal_inum)
5707 {
5708         struct inode *journal_inode;
5709
5710         /*
5711          * Test for the existence of a valid inode on disk.  Bad things
5712          * happen if we iget() an unused inode, as the subsequent iput()
5713          * will try to delete it.
5714          */
5715         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5716         if (IS_ERR(journal_inode)) {
5717                 ext4_msg(sb, KERN_ERR, "no journal found");
5718                 return NULL;
5719         }
5720         if (!journal_inode->i_nlink) {
5721                 make_bad_inode(journal_inode);
5722                 iput(journal_inode);
5723                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5724                 return NULL;
5725         }
5726
5727         ext4_debug("Journal inode found at %p: %lld bytes\n",
5728                   journal_inode, journal_inode->i_size);
5729         if (!S_ISREG(journal_inode->i_mode) || IS_ENCRYPTED(journal_inode)) {
5730                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5731                 iput(journal_inode);
5732                 return NULL;
5733         }
5734         return journal_inode;
5735 }
5736
5737 static journal_t *ext4_get_journal(struct super_block *sb,
5738                                    unsigned int journal_inum)
5739 {
5740         struct inode *journal_inode;
5741         journal_t *journal;
5742
5743         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5744                 return NULL;
5745
5746         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5747         if (!journal_inode)
5748                 return NULL;
5749
5750         journal = jbd2_journal_init_inode(journal_inode);
5751         if (!journal) {
5752                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5753                 iput(journal_inode);
5754                 return NULL;
5755         }
5756         journal->j_private = sb;
5757         ext4_init_journal_params(sb, journal);
5758         return journal;
5759 }
5760
5761 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5762                                        dev_t j_dev)
5763 {
5764         struct buffer_head *bh;
5765         journal_t *journal;
5766         ext4_fsblk_t start;
5767         ext4_fsblk_t len;
5768         int hblock, blocksize;
5769         ext4_fsblk_t sb_block;
5770         unsigned long offset;
5771         struct ext4_super_block *es;
5772         struct block_device *bdev;
5773
5774         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5775                 return NULL;
5776
5777         bdev = ext4_blkdev_get(j_dev, sb);
5778         if (bdev == NULL)
5779                 return NULL;
5780
5781         blocksize = sb->s_blocksize;
5782         hblock = bdev_logical_block_size(bdev);
5783         if (blocksize < hblock) {
5784                 ext4_msg(sb, KERN_ERR,
5785                         "blocksize too small for journal device");
5786                 goto out_bdev;
5787         }
5788
5789         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5790         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5791         set_blocksize(bdev, blocksize);
5792         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5793                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5794                        "external journal");
5795                 goto out_bdev;
5796         }
5797
5798         es = (struct ext4_super_block *) (bh->b_data + offset);
5799         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5800             !(le32_to_cpu(es->s_feature_incompat) &
5801               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5802                 ext4_msg(sb, KERN_ERR, "external journal has "
5803                                         "bad superblock");
5804                 brelse(bh);
5805                 goto out_bdev;
5806         }
5807
5808         if ((le32_to_cpu(es->s_feature_ro_compat) &
5809              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5810             es->s_checksum != ext4_superblock_csum(sb, es)) {
5811                 ext4_msg(sb, KERN_ERR, "external journal has "
5812                                        "corrupt superblock");
5813                 brelse(bh);
5814                 goto out_bdev;
5815         }
5816
5817         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5818                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5819                 brelse(bh);
5820                 goto out_bdev;
5821         }
5822
5823         len = ext4_blocks_count(es);
5824         start = sb_block + 1;
5825         brelse(bh);     /* we're done with the superblock */
5826
5827         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5828                                         start, len, blocksize);
5829         if (!journal) {
5830                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5831                 goto out_bdev;
5832         }
5833         journal->j_private = sb;
5834         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5835                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5836                 goto out_journal;
5837         }
5838         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5839                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5840                                         "user (unsupported) - %d",
5841                         be32_to_cpu(journal->j_superblock->s_nr_users));
5842                 goto out_journal;
5843         }
5844         EXT4_SB(sb)->s_journal_bdev = bdev;
5845         ext4_init_journal_params(sb, journal);
5846         return journal;
5847
5848 out_journal:
5849         jbd2_journal_destroy(journal);
5850 out_bdev:
5851         ext4_blkdev_put(bdev);
5852         return NULL;
5853 }
5854
5855 static int ext4_load_journal(struct super_block *sb,
5856                              struct ext4_super_block *es,
5857                              unsigned long journal_devnum)
5858 {
5859         journal_t *journal;
5860         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5861         dev_t journal_dev;
5862         int err = 0;
5863         int really_read_only;
5864         int journal_dev_ro;
5865
5866         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5867                 return -EFSCORRUPTED;
5868
5869         if (journal_devnum &&
5870             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5871                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5872                         "numbers have changed");
5873                 journal_dev = new_decode_dev(journal_devnum);
5874         } else
5875                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5876
5877         if (journal_inum && journal_dev) {
5878                 ext4_msg(sb, KERN_ERR,
5879                          "filesystem has both journal inode and journal device!");
5880                 return -EINVAL;
5881         }
5882
5883         if (journal_inum) {
5884                 journal = ext4_get_journal(sb, journal_inum);
5885                 if (!journal)
5886                         return -EINVAL;
5887         } else {
5888                 journal = ext4_get_dev_journal(sb, journal_dev);
5889                 if (!journal)
5890                         return -EINVAL;
5891         }
5892
5893         journal_dev_ro = bdev_read_only(journal->j_dev);
5894         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5895
5896         if (journal_dev_ro && !sb_rdonly(sb)) {
5897                 ext4_msg(sb, KERN_ERR,
5898                          "journal device read-only, try mounting with '-o ro'");
5899                 err = -EROFS;
5900                 goto err_out;
5901         }
5902
5903         /*
5904          * Are we loading a blank journal or performing recovery after a
5905          * crash?  For recovery, we need to check in advance whether we
5906          * can get read-write access to the device.
5907          */
5908         if (ext4_has_feature_journal_needs_recovery(sb)) {
5909                 if (sb_rdonly(sb)) {
5910                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5911                                         "required on readonly filesystem");
5912                         if (really_read_only) {
5913                                 ext4_msg(sb, KERN_ERR, "write access "
5914                                         "unavailable, cannot proceed "
5915                                         "(try mounting with noload)");
5916                                 err = -EROFS;
5917                                 goto err_out;
5918                         }
5919                         ext4_msg(sb, KERN_INFO, "write access will "
5920                                "be enabled during recovery");
5921                 }
5922         }
5923
5924         if (!(journal->j_flags & JBD2_BARRIER))
5925                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5926
5927         if (!ext4_has_feature_journal_needs_recovery(sb))
5928                 err = jbd2_journal_wipe(journal, !really_read_only);
5929         if (!err) {
5930                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5931                 if (save)
5932                         memcpy(save, ((char *) es) +
5933                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5934                 err = jbd2_journal_load(journal);
5935                 if (save)
5936                         memcpy(((char *) es) + EXT4_S_ERR_START,
5937                                save, EXT4_S_ERR_LEN);
5938                 kfree(save);
5939         }
5940
5941         if (err) {
5942                 ext4_msg(sb, KERN_ERR, "error loading journal");
5943                 goto err_out;
5944         }
5945
5946         EXT4_SB(sb)->s_journal = journal;
5947         err = ext4_clear_journal_err(sb, es);
5948         if (err) {
5949                 EXT4_SB(sb)->s_journal = NULL;
5950                 jbd2_journal_destroy(journal);
5951                 return err;
5952         }
5953
5954         if (!really_read_only && journal_devnum &&
5955             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5956                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5957
5958                 /* Make sure we flush the recovery flag to disk. */
5959                 ext4_commit_super(sb);
5960         }
5961
5962         return 0;
5963
5964 err_out:
5965         jbd2_journal_destroy(journal);
5966         return err;
5967 }
5968
5969 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
5970 static void ext4_update_super(struct super_block *sb)
5971 {
5972         struct ext4_sb_info *sbi = EXT4_SB(sb);
5973         struct ext4_super_block *es = sbi->s_es;
5974         struct buffer_head *sbh = sbi->s_sbh;
5975
5976         lock_buffer(sbh);
5977         /*
5978          * If the file system is mounted read-only, don't update the
5979          * superblock write time.  This avoids updating the superblock
5980          * write time when we are mounting the root file system
5981          * read/only but we need to replay the journal; at that point,
5982          * for people who are east of GMT and who make their clock
5983          * tick in localtime for Windows bug-for-bug compatibility,
5984          * the clock is set in the future, and this will cause e2fsck
5985          * to complain and force a full file system check.
5986          */
5987         if (!(sb->s_flags & SB_RDONLY))
5988                 ext4_update_tstamp(es, s_wtime);
5989         es->s_kbytes_written =
5990                 cpu_to_le64(sbi->s_kbytes_written +
5991                     ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
5992                       sbi->s_sectors_written_start) >> 1));
5993         if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
5994                 ext4_free_blocks_count_set(es,
5995                         EXT4_C2B(sbi, percpu_counter_sum_positive(
5996                                 &sbi->s_freeclusters_counter)));
5997         if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
5998                 es->s_free_inodes_count =
5999                         cpu_to_le32(percpu_counter_sum_positive(
6000                                 &sbi->s_freeinodes_counter));
6001         /* Copy error information to the on-disk superblock */
6002         spin_lock(&sbi->s_error_lock);
6003         if (sbi->s_add_error_count > 0) {
6004                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6005                 if (!es->s_first_error_time && !es->s_first_error_time_hi) {
6006                         __ext4_update_tstamp(&es->s_first_error_time,
6007                                              &es->s_first_error_time_hi,
6008                                              sbi->s_first_error_time);
6009                         strncpy(es->s_first_error_func, sbi->s_first_error_func,
6010                                 sizeof(es->s_first_error_func));
6011                         es->s_first_error_line =
6012                                 cpu_to_le32(sbi->s_first_error_line);
6013                         es->s_first_error_ino =
6014                                 cpu_to_le32(sbi->s_first_error_ino);
6015                         es->s_first_error_block =
6016                                 cpu_to_le64(sbi->s_first_error_block);
6017                         es->s_first_error_errcode =
6018                                 ext4_errno_to_code(sbi->s_first_error_code);
6019                 }
6020                 __ext4_update_tstamp(&es->s_last_error_time,
6021                                      &es->s_last_error_time_hi,
6022                                      sbi->s_last_error_time);
6023                 strncpy(es->s_last_error_func, sbi->s_last_error_func,
6024                         sizeof(es->s_last_error_func));
6025                 es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
6026                 es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
6027                 es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
6028                 es->s_last_error_errcode =
6029                                 ext4_errno_to_code(sbi->s_last_error_code);
6030                 /*
6031                  * Start the daily error reporting function if it hasn't been
6032                  * started already
6033                  */
6034                 if (!es->s_error_count)
6035                         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
6036                 le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
6037                 sbi->s_add_error_count = 0;
6038         }
6039         spin_unlock(&sbi->s_error_lock);
6040
6041         ext4_superblock_csum_set(sb);
6042         unlock_buffer(sbh);
6043 }
6044
6045 static int ext4_commit_super(struct super_block *sb)
6046 {
6047         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
6048
6049         if (!sbh)
6050                 return -EINVAL;
6051         if (block_device_ejected(sb))
6052                 return -ENODEV;
6053
6054         ext4_update_super(sb);
6055
6056         lock_buffer(sbh);
6057         /* Buffer got discarded which means block device got invalidated */
6058         if (!buffer_mapped(sbh)) {
6059                 unlock_buffer(sbh);
6060                 return -EIO;
6061         }
6062
6063         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
6064                 /*
6065                  * Oh, dear.  A previous attempt to write the
6066                  * superblock failed.  This could happen because the
6067                  * USB device was yanked out.  Or it could happen to
6068                  * be a transient write error and maybe the block will
6069                  * be remapped.  Nothing we can do but to retry the
6070                  * write and hope for the best.
6071                  */
6072                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
6073                        "superblock detected");
6074                 clear_buffer_write_io_error(sbh);
6075                 set_buffer_uptodate(sbh);
6076         }
6077         get_bh(sbh);
6078         /* Clear potential dirty bit if it was journalled update */
6079         clear_buffer_dirty(sbh);
6080         sbh->b_end_io = end_buffer_write_sync;
6081         submit_bh(REQ_OP_WRITE | REQ_SYNC |
6082                   (test_opt(sb, BARRIER) ? REQ_FUA : 0), sbh);
6083         wait_on_buffer(sbh);
6084         if (buffer_write_io_error(sbh)) {
6085                 ext4_msg(sb, KERN_ERR, "I/O error while writing "
6086                        "superblock");
6087                 clear_buffer_write_io_error(sbh);
6088                 set_buffer_uptodate(sbh);
6089                 return -EIO;
6090         }
6091         return 0;
6092 }
6093
6094 /*
6095  * Have we just finished recovery?  If so, and if we are mounting (or
6096  * remounting) the filesystem readonly, then we will end up with a
6097  * consistent fs on disk.  Record that fact.
6098  */
6099 static int ext4_mark_recovery_complete(struct super_block *sb,
6100                                        struct ext4_super_block *es)
6101 {
6102         int err;
6103         journal_t *journal = EXT4_SB(sb)->s_journal;
6104
6105         if (!ext4_has_feature_journal(sb)) {
6106                 if (journal != NULL) {
6107                         ext4_error(sb, "Journal got removed while the fs was "
6108                                    "mounted!");
6109                         return -EFSCORRUPTED;
6110                 }
6111                 return 0;
6112         }
6113         jbd2_journal_lock_updates(journal);
6114         err = jbd2_journal_flush(journal, 0);
6115         if (err < 0)
6116                 goto out;
6117
6118         if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6119             ext4_has_feature_orphan_present(sb))) {
6120                 if (!ext4_orphan_file_empty(sb)) {
6121                         ext4_error(sb, "Orphan file not empty on read-only fs.");
6122                         err = -EFSCORRUPTED;
6123                         goto out;
6124                 }
6125                 ext4_clear_feature_journal_needs_recovery(sb);
6126                 ext4_clear_feature_orphan_present(sb);
6127                 ext4_commit_super(sb);
6128         }
6129 out:
6130         jbd2_journal_unlock_updates(journal);
6131         return err;
6132 }
6133
6134 /*
6135  * If we are mounting (or read-write remounting) a filesystem whose journal
6136  * has recorded an error from a previous lifetime, move that error to the
6137  * main filesystem now.
6138  */
6139 static int ext4_clear_journal_err(struct super_block *sb,
6140                                    struct ext4_super_block *es)
6141 {
6142         journal_t *journal;
6143         int j_errno;
6144         const char *errstr;
6145
6146         if (!ext4_has_feature_journal(sb)) {
6147                 ext4_error(sb, "Journal got removed while the fs was mounted!");
6148                 return -EFSCORRUPTED;
6149         }
6150
6151         journal = EXT4_SB(sb)->s_journal;
6152
6153         /*
6154          * Now check for any error status which may have been recorded in the
6155          * journal by a prior ext4_error() or ext4_abort()
6156          */
6157
6158         j_errno = jbd2_journal_errno(journal);
6159         if (j_errno) {
6160                 char nbuf[16];
6161
6162                 errstr = ext4_decode_error(sb, j_errno, nbuf);
6163                 ext4_warning(sb, "Filesystem error recorded "
6164                              "from previous mount: %s", errstr);
6165                 ext4_warning(sb, "Marking fs in need of filesystem check.");
6166
6167                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6168                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6169                 ext4_commit_super(sb);
6170
6171                 jbd2_journal_clear_err(journal);
6172                 jbd2_journal_update_sb_errno(journal);
6173         }
6174         return 0;
6175 }
6176
6177 /*
6178  * Force the running and committing transactions to commit,
6179  * and wait on the commit.
6180  */
6181 int ext4_force_commit(struct super_block *sb)
6182 {
6183         journal_t *journal;
6184
6185         if (sb_rdonly(sb))
6186                 return 0;
6187
6188         journal = EXT4_SB(sb)->s_journal;
6189         return ext4_journal_force_commit(journal);
6190 }
6191
6192 static int ext4_sync_fs(struct super_block *sb, int wait)
6193 {
6194         int ret = 0;
6195         tid_t target;
6196         bool needs_barrier = false;
6197         struct ext4_sb_info *sbi = EXT4_SB(sb);
6198
6199         if (unlikely(ext4_forced_shutdown(sbi)))
6200                 return 0;
6201
6202         trace_ext4_sync_fs(sb, wait);
6203         flush_workqueue(sbi->rsv_conversion_wq);
6204         /*
6205          * Writeback quota in non-journalled quota case - journalled quota has
6206          * no dirty dquots
6207          */
6208         dquot_writeback_dquots(sb, -1);
6209         /*
6210          * Data writeback is possible w/o journal transaction, so barrier must
6211          * being sent at the end of the function. But we can skip it if
6212          * transaction_commit will do it for us.
6213          */
6214         if (sbi->s_journal) {
6215                 target = jbd2_get_latest_transaction(sbi->s_journal);
6216                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6217                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6218                         needs_barrier = true;
6219
6220                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6221                         if (wait)
6222                                 ret = jbd2_log_wait_commit(sbi->s_journal,
6223                                                            target);
6224                 }
6225         } else if (wait && test_opt(sb, BARRIER))
6226                 needs_barrier = true;
6227         if (needs_barrier) {
6228                 int err;
6229                 err = blkdev_issue_flush(sb->s_bdev);
6230                 if (!ret)
6231                         ret = err;
6232         }
6233
6234         return ret;
6235 }
6236
6237 /*
6238  * LVM calls this function before a (read-only) snapshot is created.  This
6239  * gives us a chance to flush the journal completely and mark the fs clean.
6240  *
6241  * Note that only this function cannot bring a filesystem to be in a clean
6242  * state independently. It relies on upper layer to stop all data & metadata
6243  * modifications.
6244  */
6245 static int ext4_freeze(struct super_block *sb)
6246 {
6247         int error = 0;
6248         journal_t *journal;
6249
6250         if (sb_rdonly(sb))
6251                 return 0;
6252
6253         journal = EXT4_SB(sb)->s_journal;
6254
6255         if (journal) {
6256                 /* Now we set up the journal barrier. */
6257                 jbd2_journal_lock_updates(journal);
6258
6259                 /*
6260                  * Don't clear the needs_recovery flag if we failed to
6261                  * flush the journal.
6262                  */
6263                 error = jbd2_journal_flush(journal, 0);
6264                 if (error < 0)
6265                         goto out;
6266
6267                 /* Journal blocked and flushed, clear needs_recovery flag. */
6268                 ext4_clear_feature_journal_needs_recovery(sb);
6269                 if (ext4_orphan_file_empty(sb))
6270                         ext4_clear_feature_orphan_present(sb);
6271         }
6272
6273         error = ext4_commit_super(sb);
6274 out:
6275         if (journal)
6276                 /* we rely on upper layer to stop further updates */
6277                 jbd2_journal_unlock_updates(journal);
6278         return error;
6279 }
6280
6281 /*
6282  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6283  * flag here, even though the filesystem is not technically dirty yet.
6284  */
6285 static int ext4_unfreeze(struct super_block *sb)
6286 {
6287         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
6288                 return 0;
6289
6290         if (EXT4_SB(sb)->s_journal) {
6291                 /* Reset the needs_recovery flag before the fs is unlocked. */
6292                 ext4_set_feature_journal_needs_recovery(sb);
6293                 if (ext4_has_feature_orphan_file(sb))
6294                         ext4_set_feature_orphan_present(sb);
6295         }
6296
6297         ext4_commit_super(sb);
6298         return 0;
6299 }
6300
6301 /*
6302  * Structure to save mount options for ext4_remount's benefit
6303  */
6304 struct ext4_mount_options {
6305         unsigned long s_mount_opt;
6306         unsigned long s_mount_opt2;
6307         kuid_t s_resuid;
6308         kgid_t s_resgid;
6309         unsigned long s_commit_interval;
6310         u32 s_min_batch_time, s_max_batch_time;
6311 #ifdef CONFIG_QUOTA
6312         int s_jquota_fmt;
6313         char *s_qf_names[EXT4_MAXQUOTAS];
6314 #endif
6315 };
6316
6317 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6318 {
6319         struct ext4_fs_context *ctx = fc->fs_private;
6320         struct ext4_super_block *es;
6321         struct ext4_sb_info *sbi = EXT4_SB(sb);
6322         unsigned long old_sb_flags;
6323         struct ext4_mount_options old_opts;
6324         ext4_group_t g;
6325         int err = 0;
6326 #ifdef CONFIG_QUOTA
6327         int enable_quota = 0;
6328         int i, j;
6329         char *to_free[EXT4_MAXQUOTAS];
6330 #endif
6331
6332
6333         /* Store the original options */
6334         old_sb_flags = sb->s_flags;
6335         old_opts.s_mount_opt = sbi->s_mount_opt;
6336         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6337         old_opts.s_resuid = sbi->s_resuid;
6338         old_opts.s_resgid = sbi->s_resgid;
6339         old_opts.s_commit_interval = sbi->s_commit_interval;
6340         old_opts.s_min_batch_time = sbi->s_min_batch_time;
6341         old_opts.s_max_batch_time = sbi->s_max_batch_time;
6342 #ifdef CONFIG_QUOTA
6343         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6344         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6345                 if (sbi->s_qf_names[i]) {
6346                         char *qf_name = get_qf_name(sb, sbi, i);
6347
6348                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6349                         if (!old_opts.s_qf_names[i]) {
6350                                 for (j = 0; j < i; j++)
6351                                         kfree(old_opts.s_qf_names[j]);
6352                                 return -ENOMEM;
6353                         }
6354                 } else
6355                         old_opts.s_qf_names[i] = NULL;
6356 #endif
6357         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)) {
6358                 if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6359                         ctx->journal_ioprio =
6360                                 sbi->s_journal->j_task->io_context->ioprio;
6361                 else
6362                         ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
6363
6364         }
6365
6366         ext4_apply_options(fc, sb);
6367
6368         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6369             test_opt(sb, JOURNAL_CHECKSUM)) {
6370                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6371                          "during remount not supported; ignoring");
6372                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6373         }
6374
6375         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6376                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6377                         ext4_msg(sb, KERN_ERR, "can't mount with "
6378                                  "both data=journal and delalloc");
6379                         err = -EINVAL;
6380                         goto restore_opts;
6381                 }
6382                 if (test_opt(sb, DIOREAD_NOLOCK)) {
6383                         ext4_msg(sb, KERN_ERR, "can't mount with "
6384                                  "both data=journal and dioread_nolock");
6385                         err = -EINVAL;
6386                         goto restore_opts;
6387                 }
6388         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6389                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6390                         ext4_msg(sb, KERN_ERR, "can't mount with "
6391                                 "journal_async_commit in data=ordered mode");
6392                         err = -EINVAL;
6393                         goto restore_opts;
6394                 }
6395         }
6396
6397         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6398                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6399                 err = -EINVAL;
6400                 goto restore_opts;
6401         }
6402
6403         if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
6404                 ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6405
6406         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6407                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6408
6409         es = sbi->s_es;
6410
6411         if (sbi->s_journal) {
6412                 ext4_init_journal_params(sb, sbi->s_journal);
6413                 set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6414         }
6415
6416         /* Flush outstanding errors before changing fs state */
6417         flush_work(&sbi->s_error_work);
6418
6419         if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6420                 if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
6421                         err = -EROFS;
6422                         goto restore_opts;
6423                 }
6424
6425                 if (fc->sb_flags & SB_RDONLY) {
6426                         err = sync_filesystem(sb);
6427                         if (err < 0)
6428                                 goto restore_opts;
6429                         err = dquot_suspend(sb, -1);
6430                         if (err < 0)
6431                                 goto restore_opts;
6432
6433                         /*
6434                          * First of all, the unconditional stuff we have to do
6435                          * to disable replay of the journal when we next remount
6436                          */
6437                         sb->s_flags |= SB_RDONLY;
6438
6439                         /*
6440                          * OK, test if we are remounting a valid rw partition
6441                          * readonly, and if so set the rdonly flag and then
6442                          * mark the partition as valid again.
6443                          */
6444                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6445                             (sbi->s_mount_state & EXT4_VALID_FS))
6446                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
6447
6448                         if (sbi->s_journal) {
6449                                 /*
6450                                  * We let remount-ro finish even if marking fs
6451                                  * as clean failed...
6452                                  */
6453                                 ext4_mark_recovery_complete(sb, es);
6454                         }
6455                 } else {
6456                         /* Make sure we can mount this feature set readwrite */
6457                         if (ext4_has_feature_readonly(sb) ||
6458                             !ext4_feature_set_ok(sb, 0)) {
6459                                 err = -EROFS;
6460                                 goto restore_opts;
6461                         }
6462                         /*
6463                          * Make sure the group descriptor checksums
6464                          * are sane.  If they aren't, refuse to remount r/w.
6465                          */
6466                         for (g = 0; g < sbi->s_groups_count; g++) {
6467                                 struct ext4_group_desc *gdp =
6468                                         ext4_get_group_desc(sb, g, NULL);
6469
6470                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6471                                         ext4_msg(sb, KERN_ERR,
6472                "ext4_remount: Checksum for group %u failed (%u!=%u)",
6473                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6474                                                le16_to_cpu(gdp->bg_checksum));
6475                                         err = -EFSBADCRC;
6476                                         goto restore_opts;
6477                                 }
6478                         }
6479
6480                         /*
6481                          * If we have an unprocessed orphan list hanging
6482                          * around from a previously readonly bdev mount,
6483                          * require a full umount/remount for now.
6484                          */
6485                         if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6486                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
6487                                        "remount RDWR because of unprocessed "
6488                                        "orphan inode list.  Please "
6489                                        "umount/remount instead");
6490                                 err = -EINVAL;
6491                                 goto restore_opts;
6492                         }
6493
6494                         /*
6495                          * Mounting a RDONLY partition read-write, so reread
6496                          * and store the current valid flag.  (It may have
6497                          * been changed by e2fsck since we originally mounted
6498                          * the partition.)
6499                          */
6500                         if (sbi->s_journal) {
6501                                 err = ext4_clear_journal_err(sb, es);
6502                                 if (err)
6503                                         goto restore_opts;
6504                         }
6505                         sbi->s_mount_state = (le16_to_cpu(es->s_state) &
6506                                               ~EXT4_FC_REPLAY);
6507
6508                         err = ext4_setup_super(sb, es, 0);
6509                         if (err)
6510                                 goto restore_opts;
6511
6512                         sb->s_flags &= ~SB_RDONLY;
6513                         if (ext4_has_feature_mmp(sb))
6514                                 if (ext4_multi_mount_protect(sb,
6515                                                 le64_to_cpu(es->s_mmp_block))) {
6516                                         err = -EROFS;
6517                                         goto restore_opts;
6518                                 }
6519 #ifdef CONFIG_QUOTA
6520                         enable_quota = 1;
6521 #endif
6522                 }
6523         }
6524
6525         /*
6526          * Reinitialize lazy itable initialization thread based on
6527          * current settings
6528          */
6529         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6530                 ext4_unregister_li_request(sb);
6531         else {
6532                 ext4_group_t first_not_zeroed;
6533                 first_not_zeroed = ext4_has_uninit_itable(sb);
6534                 ext4_register_li_request(sb, first_not_zeroed);
6535         }
6536
6537         /*
6538          * Handle creation of system zone data early because it can fail.
6539          * Releasing of existing data is done when we are sure remount will
6540          * succeed.
6541          */
6542         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6543                 err = ext4_setup_system_zone(sb);
6544                 if (err)
6545                         goto restore_opts;
6546         }
6547
6548         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6549                 err = ext4_commit_super(sb);
6550                 if (err)
6551                         goto restore_opts;
6552         }
6553
6554 #ifdef CONFIG_QUOTA
6555         /* Release old quota file names */
6556         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6557                 kfree(old_opts.s_qf_names[i]);
6558         if (enable_quota) {
6559                 if (sb_any_quota_suspended(sb))
6560                         dquot_resume(sb, -1);
6561                 else if (ext4_has_feature_quota(sb)) {
6562                         err = ext4_enable_quotas(sb);
6563                         if (err)
6564                                 goto restore_opts;
6565                 }
6566         }
6567 #endif
6568         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6569                 ext4_release_system_zone(sb);
6570
6571         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6572                 ext4_stop_mmpd(sbi);
6573
6574         return 0;
6575
6576 restore_opts:
6577         sb->s_flags = old_sb_flags;
6578         sbi->s_mount_opt = old_opts.s_mount_opt;
6579         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6580         sbi->s_resuid = old_opts.s_resuid;
6581         sbi->s_resgid = old_opts.s_resgid;
6582         sbi->s_commit_interval = old_opts.s_commit_interval;
6583         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6584         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6585         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6586                 ext4_release_system_zone(sb);
6587 #ifdef CONFIG_QUOTA
6588         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6589         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6590                 to_free[i] = get_qf_name(sb, sbi, i);
6591                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6592         }
6593         synchronize_rcu();
6594         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6595                 kfree(to_free[i]);
6596 #endif
6597         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6598                 ext4_stop_mmpd(sbi);
6599         return err;
6600 }
6601
6602 static int ext4_reconfigure(struct fs_context *fc)
6603 {
6604         struct super_block *sb = fc->root->d_sb;
6605         int ret;
6606
6607         fc->s_fs_info = EXT4_SB(sb);
6608
6609         ret = ext4_check_opt_consistency(fc, sb);
6610         if (ret < 0)
6611                 return ret;
6612
6613         ret = __ext4_remount(fc, sb);
6614         if (ret < 0)
6615                 return ret;
6616
6617         ext4_msg(sb, KERN_INFO, "re-mounted %pU. Quota mode: %s.",
6618                  &sb->s_uuid, ext4_quota_mode(sb));
6619
6620         return 0;
6621 }
6622
6623 #ifdef CONFIG_QUOTA
6624 static int ext4_statfs_project(struct super_block *sb,
6625                                kprojid_t projid, struct kstatfs *buf)
6626 {
6627         struct kqid qid;
6628         struct dquot *dquot;
6629         u64 limit;
6630         u64 curblock;
6631
6632         qid = make_kqid_projid(projid);
6633         dquot = dqget(sb, qid);
6634         if (IS_ERR(dquot))
6635                 return PTR_ERR(dquot);
6636         spin_lock(&dquot->dq_dqb_lock);
6637
6638         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6639                              dquot->dq_dqb.dqb_bhardlimit);
6640         limit >>= sb->s_blocksize_bits;
6641
6642         if (limit && buf->f_blocks > limit) {
6643                 curblock = (dquot->dq_dqb.dqb_curspace +
6644                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6645                 buf->f_blocks = limit;
6646                 buf->f_bfree = buf->f_bavail =
6647                         (buf->f_blocks > curblock) ?
6648                          (buf->f_blocks - curblock) : 0;
6649         }
6650
6651         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6652                              dquot->dq_dqb.dqb_ihardlimit);
6653         if (limit && buf->f_files > limit) {
6654                 buf->f_files = limit;
6655                 buf->f_ffree =
6656                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6657                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6658         }
6659
6660         spin_unlock(&dquot->dq_dqb_lock);
6661         dqput(dquot);
6662         return 0;
6663 }
6664 #endif
6665
6666 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6667 {
6668         struct super_block *sb = dentry->d_sb;
6669         struct ext4_sb_info *sbi = EXT4_SB(sb);
6670         struct ext4_super_block *es = sbi->s_es;
6671         ext4_fsblk_t overhead = 0, resv_blocks;
6672         s64 bfree;
6673         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6674
6675         if (!test_opt(sb, MINIX_DF))
6676                 overhead = sbi->s_overhead;
6677
6678         buf->f_type = EXT4_SUPER_MAGIC;
6679         buf->f_bsize = sb->s_blocksize;
6680         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6681         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6682                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6683         /* prevent underflow in case that few free space is available */
6684         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6685         buf->f_bavail = buf->f_bfree -
6686                         (ext4_r_blocks_count(es) + resv_blocks);
6687         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6688                 buf->f_bavail = 0;
6689         buf->f_files = le32_to_cpu(es->s_inodes_count);
6690         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6691         buf->f_namelen = EXT4_NAME_LEN;
6692         buf->f_fsid = uuid_to_fsid(es->s_uuid);
6693
6694 #ifdef CONFIG_QUOTA
6695         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6696             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6697                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6698 #endif
6699         return 0;
6700 }
6701
6702
6703 #ifdef CONFIG_QUOTA
6704
6705 /*
6706  * Helper functions so that transaction is started before we acquire dqio_sem
6707  * to keep correct lock ordering of transaction > dqio_sem
6708  */
6709 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6710 {
6711         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6712 }
6713
6714 static int ext4_write_dquot(struct dquot *dquot)
6715 {
6716         int ret, err;
6717         handle_t *handle;
6718         struct inode *inode;
6719
6720         inode = dquot_to_inode(dquot);
6721         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6722                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6723         if (IS_ERR(handle))
6724                 return PTR_ERR(handle);
6725         ret = dquot_commit(dquot);
6726         err = ext4_journal_stop(handle);
6727         if (!ret)
6728                 ret = err;
6729         return ret;
6730 }
6731
6732 static int ext4_acquire_dquot(struct dquot *dquot)
6733 {
6734         int ret, err;
6735         handle_t *handle;
6736
6737         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6738                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6739         if (IS_ERR(handle))
6740                 return PTR_ERR(handle);
6741         ret = dquot_acquire(dquot);
6742         err = ext4_journal_stop(handle);
6743         if (!ret)
6744                 ret = err;
6745         return ret;
6746 }
6747
6748 static int ext4_release_dquot(struct dquot *dquot)
6749 {
6750         int ret, err;
6751         handle_t *handle;
6752
6753         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6754                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6755         if (IS_ERR(handle)) {
6756                 /* Release dquot anyway to avoid endless cycle in dqput() */
6757                 dquot_release(dquot);
6758                 return PTR_ERR(handle);
6759         }
6760         ret = dquot_release(dquot);
6761         err = ext4_journal_stop(handle);
6762         if (!ret)
6763                 ret = err;
6764         return ret;
6765 }
6766
6767 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6768 {
6769         struct super_block *sb = dquot->dq_sb;
6770
6771         if (ext4_is_quota_journalled(sb)) {
6772                 dquot_mark_dquot_dirty(dquot);
6773                 return ext4_write_dquot(dquot);
6774         } else {
6775                 return dquot_mark_dquot_dirty(dquot);
6776         }
6777 }
6778
6779 static int ext4_write_info(struct super_block *sb, int type)
6780 {
6781         int ret, err;
6782         handle_t *handle;
6783
6784         /* Data block + inode block */
6785         handle = ext4_journal_start_sb(sb, EXT4_HT_QUOTA, 2);
6786         if (IS_ERR(handle))
6787                 return PTR_ERR(handle);
6788         ret = dquot_commit_info(sb, type);
6789         err = ext4_journal_stop(handle);
6790         if (!ret)
6791                 ret = err;
6792         return ret;
6793 }
6794
6795 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6796 {
6797         struct ext4_inode_info *ei = EXT4_I(inode);
6798
6799         /* The first argument of lockdep_set_subclass has to be
6800          * *exactly* the same as the argument to init_rwsem() --- in
6801          * this case, in init_once() --- or lockdep gets unhappy
6802          * because the name of the lock is set using the
6803          * stringification of the argument to init_rwsem().
6804          */
6805         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6806         lockdep_set_subclass(&ei->i_data_sem, subclass);
6807 }
6808
6809 /*
6810  * Standard function to be called on quota_on
6811  */
6812 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6813                          const struct path *path)
6814 {
6815         int err;
6816
6817         if (!test_opt(sb, QUOTA))
6818                 return -EINVAL;
6819
6820         /* Quotafile not on the same filesystem? */
6821         if (path->dentry->d_sb != sb)
6822                 return -EXDEV;
6823
6824         /* Quota already enabled for this file? */
6825         if (IS_NOQUOTA(d_inode(path->dentry)))
6826                 return -EBUSY;
6827
6828         /* Journaling quota? */
6829         if (EXT4_SB(sb)->s_qf_names[type]) {
6830                 /* Quotafile not in fs root? */
6831                 if (path->dentry->d_parent != sb->s_root)
6832                         ext4_msg(sb, KERN_WARNING,
6833                                 "Quota file not on filesystem root. "
6834                                 "Journaled quota will not work");
6835                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6836         } else {
6837                 /*
6838                  * Clear the flag just in case mount options changed since
6839                  * last time.
6840                  */
6841                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6842         }
6843
6844         /*
6845          * When we journal data on quota file, we have to flush journal to see
6846          * all updates to the file when we bypass pagecache...
6847          */
6848         if (EXT4_SB(sb)->s_journal &&
6849             ext4_should_journal_data(d_inode(path->dentry))) {
6850                 /*
6851                  * We don't need to lock updates but journal_flush() could
6852                  * otherwise be livelocked...
6853                  */
6854                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6855                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal, 0);
6856                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6857                 if (err)
6858                         return err;
6859         }
6860
6861         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6862         err = dquot_quota_on(sb, type, format_id, path);
6863         if (!err) {
6864                 struct inode *inode = d_inode(path->dentry);
6865                 handle_t *handle;
6866
6867                 /*
6868                  * Set inode flags to prevent userspace from messing with quota
6869                  * files. If this fails, we return success anyway since quotas
6870                  * are already enabled and this is not a hard failure.
6871                  */
6872                 inode_lock(inode);
6873                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6874                 if (IS_ERR(handle))
6875                         goto unlock_inode;
6876                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6877                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6878                                 S_NOATIME | S_IMMUTABLE);
6879                 err = ext4_mark_inode_dirty(handle, inode);
6880                 ext4_journal_stop(handle);
6881         unlock_inode:
6882                 inode_unlock(inode);
6883                 if (err)
6884                         dquot_quota_off(sb, type);
6885         }
6886         if (err)
6887                 lockdep_set_quota_inode(path->dentry->d_inode,
6888                                              I_DATA_SEM_NORMAL);
6889         return err;
6890 }
6891
6892 static inline bool ext4_check_quota_inum(int type, unsigned long qf_inum)
6893 {
6894         switch (type) {
6895         case USRQUOTA:
6896                 return qf_inum == EXT4_USR_QUOTA_INO;
6897         case GRPQUOTA:
6898                 return qf_inum == EXT4_GRP_QUOTA_INO;
6899         case PRJQUOTA:
6900                 return qf_inum >= EXT4_GOOD_OLD_FIRST_INO;
6901         default:
6902                 BUG();
6903         }
6904 }
6905
6906 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6907                              unsigned int flags)
6908 {
6909         int err;
6910         struct inode *qf_inode;
6911         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6912                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6913                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6914                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6915         };
6916
6917         BUG_ON(!ext4_has_feature_quota(sb));
6918
6919         if (!qf_inums[type])
6920                 return -EPERM;
6921
6922         if (!ext4_check_quota_inum(type, qf_inums[type])) {
6923                 ext4_error(sb, "Bad quota inum: %lu, type: %d",
6924                                 qf_inums[type], type);
6925                 return -EUCLEAN;
6926         }
6927
6928         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6929         if (IS_ERR(qf_inode)) {
6930                 ext4_error(sb, "Bad quota inode: %lu, type: %d",
6931                                 qf_inums[type], type);
6932                 return PTR_ERR(qf_inode);
6933         }
6934
6935         /* Don't account quota for quota files to avoid recursion */
6936         qf_inode->i_flags |= S_NOQUOTA;
6937         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6938         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6939         if (err)
6940                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6941         iput(qf_inode);
6942
6943         return err;
6944 }
6945
6946 /* Enable usage tracking for all quota types. */
6947 int ext4_enable_quotas(struct super_block *sb)
6948 {
6949         int type, err = 0;
6950         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6951                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6952                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6953                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6954         };
6955         bool quota_mopt[EXT4_MAXQUOTAS] = {
6956                 test_opt(sb, USRQUOTA),
6957                 test_opt(sb, GRPQUOTA),
6958                 test_opt(sb, PRJQUOTA),
6959         };
6960
6961         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6962         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6963                 if (qf_inums[type]) {
6964                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6965                                 DQUOT_USAGE_ENABLED |
6966                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6967                         if (err) {
6968                                 ext4_warning(sb,
6969                                         "Failed to enable quota tracking "
6970                                         "(type=%d, err=%d, ino=%lu). "
6971                                         "Please run e2fsck to fix.", type,
6972                                         err, qf_inums[type]);
6973                                 for (type--; type >= 0; type--) {
6974                                         struct inode *inode;
6975
6976                                         inode = sb_dqopt(sb)->files[type];
6977                                         if (inode)
6978                                                 inode = igrab(inode);
6979                                         dquot_quota_off(sb, type);
6980                                         if (inode) {
6981                                                 lockdep_set_quota_inode(inode,
6982                                                         I_DATA_SEM_NORMAL);
6983                                                 iput(inode);
6984                                         }
6985                                 }
6986
6987                                 return err;
6988                         }
6989                 }
6990         }
6991         return 0;
6992 }
6993
6994 static int ext4_quota_off(struct super_block *sb, int type)
6995 {
6996         struct inode *inode = sb_dqopt(sb)->files[type];
6997         handle_t *handle;
6998         int err;
6999
7000         /* Force all delayed allocation blocks to be allocated.
7001          * Caller already holds s_umount sem */
7002         if (test_opt(sb, DELALLOC))
7003                 sync_filesystem(sb);
7004
7005         if (!inode || !igrab(inode))
7006                 goto out;
7007
7008         err = dquot_quota_off(sb, type);
7009         if (err || ext4_has_feature_quota(sb))
7010                 goto out_put;
7011
7012         inode_lock(inode);
7013         /*
7014          * Update modification times of quota files when userspace can
7015          * start looking at them. If we fail, we return success anyway since
7016          * this is not a hard failure and quotas are already disabled.
7017          */
7018         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7019         if (IS_ERR(handle)) {
7020                 err = PTR_ERR(handle);
7021                 goto out_unlock;
7022         }
7023         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
7024         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
7025         inode->i_mtime = inode->i_ctime = current_time(inode);
7026         err = ext4_mark_inode_dirty(handle, inode);
7027         ext4_journal_stop(handle);
7028 out_unlock:
7029         inode_unlock(inode);
7030 out_put:
7031         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
7032         iput(inode);
7033         return err;
7034 out:
7035         return dquot_quota_off(sb, type);
7036 }
7037
7038 /* Read data from quotafile - avoid pagecache and such because we cannot afford
7039  * acquiring the locks... As quota files are never truncated and quota code
7040  * itself serializes the operations (and no one else should touch the files)
7041  * we don't have to be afraid of races */
7042 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
7043                                size_t len, loff_t off)
7044 {
7045         struct inode *inode = sb_dqopt(sb)->files[type];
7046         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7047         int offset = off & (sb->s_blocksize - 1);
7048         int tocopy;
7049         size_t toread;
7050         struct buffer_head *bh;
7051         loff_t i_size = i_size_read(inode);
7052
7053         if (off > i_size)
7054                 return 0;
7055         if (off+len > i_size)
7056                 len = i_size-off;
7057         toread = len;
7058         while (toread > 0) {
7059                 tocopy = min_t(unsigned long, sb->s_blocksize - offset, toread);
7060                 bh = ext4_bread(NULL, inode, blk, 0);
7061                 if (IS_ERR(bh))
7062                         return PTR_ERR(bh);
7063                 if (!bh)        /* A hole? */
7064                         memset(data, 0, tocopy);
7065                 else
7066                         memcpy(data, bh->b_data+offset, tocopy);
7067                 brelse(bh);
7068                 offset = 0;
7069                 toread -= tocopy;
7070                 data += tocopy;
7071                 blk++;
7072         }
7073         return len;
7074 }
7075
7076 /* Write to quotafile (we know the transaction is already started and has
7077  * enough credits) */
7078 static ssize_t ext4_quota_write(struct super_block *sb, int type,
7079                                 const char *data, size_t len, loff_t off)
7080 {
7081         struct inode *inode = sb_dqopt(sb)->files[type];
7082         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7083         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
7084         int retries = 0;
7085         struct buffer_head *bh;
7086         handle_t *handle = journal_current_handle();
7087
7088         if (!handle) {
7089                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7090                         " cancelled because transaction is not started",
7091                         (unsigned long long)off, (unsigned long long)len);
7092                 return -EIO;
7093         }
7094         /*
7095          * Since we account only one data block in transaction credits,
7096          * then it is impossible to cross a block boundary.
7097          */
7098         if (sb->s_blocksize - offset < len) {
7099                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7100                         " cancelled because not block aligned",
7101                         (unsigned long long)off, (unsigned long long)len);
7102                 return -EIO;
7103         }
7104
7105         do {
7106                 bh = ext4_bread(handle, inode, blk,
7107                                 EXT4_GET_BLOCKS_CREATE |
7108                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
7109         } while (PTR_ERR(bh) == -ENOSPC &&
7110                  ext4_should_retry_alloc(inode->i_sb, &retries));
7111         if (IS_ERR(bh))
7112                 return PTR_ERR(bh);
7113         if (!bh)
7114                 goto out;
7115         BUFFER_TRACE(bh, "get write access");
7116         err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
7117         if (err) {
7118                 brelse(bh);
7119                 return err;
7120         }
7121         lock_buffer(bh);
7122         memcpy(bh->b_data+offset, data, len);
7123         flush_dcache_page(bh->b_page);
7124         unlock_buffer(bh);
7125         err = ext4_handle_dirty_metadata(handle, NULL, bh);
7126         brelse(bh);
7127 out:
7128         if (inode->i_size < off + len) {
7129                 i_size_write(inode, off + len);
7130                 EXT4_I(inode)->i_disksize = inode->i_size;
7131                 err2 = ext4_mark_inode_dirty(handle, inode);
7132                 if (unlikely(err2 && !err))
7133                         err = err2;
7134         }
7135         return err ? err : len;
7136 }
7137 #endif
7138
7139 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
7140 static inline void register_as_ext2(void)
7141 {
7142         int err = register_filesystem(&ext2_fs_type);
7143         if (err)
7144                 printk(KERN_WARNING
7145                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7146 }
7147
7148 static inline void unregister_as_ext2(void)
7149 {
7150         unregister_filesystem(&ext2_fs_type);
7151 }
7152
7153 static inline int ext2_feature_set_ok(struct super_block *sb)
7154 {
7155         if (ext4_has_unknown_ext2_incompat_features(sb))
7156                 return 0;
7157         if (sb_rdonly(sb))
7158                 return 1;
7159         if (ext4_has_unknown_ext2_ro_compat_features(sb))
7160                 return 0;
7161         return 1;
7162 }
7163 #else
7164 static inline void register_as_ext2(void) { }
7165 static inline void unregister_as_ext2(void) { }
7166 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7167 #endif
7168
7169 static inline void register_as_ext3(void)
7170 {
7171         int err = register_filesystem(&ext3_fs_type);
7172         if (err)
7173                 printk(KERN_WARNING
7174                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7175 }
7176
7177 static inline void unregister_as_ext3(void)
7178 {
7179         unregister_filesystem(&ext3_fs_type);
7180 }
7181
7182 static inline int ext3_feature_set_ok(struct super_block *sb)
7183 {
7184         if (ext4_has_unknown_ext3_incompat_features(sb))
7185                 return 0;
7186         if (!ext4_has_feature_journal(sb))
7187                 return 0;
7188         if (sb_rdonly(sb))
7189                 return 1;
7190         if (ext4_has_unknown_ext3_ro_compat_features(sb))
7191                 return 0;
7192         return 1;
7193 }
7194
7195 static struct file_system_type ext4_fs_type = {
7196         .owner                  = THIS_MODULE,
7197         .name                   = "ext4",
7198         .init_fs_context        = ext4_init_fs_context,
7199         .parameters             = ext4_param_specs,
7200         .kill_sb                = kill_block_super,
7201         .fs_flags               = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
7202 };
7203 MODULE_ALIAS_FS("ext4");
7204
7205 /* Shared across all ext4 file systems */
7206 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
7207
7208 static int __init ext4_init_fs(void)
7209 {
7210         int i, err;
7211
7212         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7213         ext4_li_info = NULL;
7214
7215         /* Build-time check for flags consistency */
7216         ext4_check_flag_values();
7217
7218         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
7219                 init_waitqueue_head(&ext4__ioend_wq[i]);
7220
7221         err = ext4_init_es();
7222         if (err)
7223                 return err;
7224
7225         err = ext4_init_pending();
7226         if (err)
7227                 goto out7;
7228
7229         err = ext4_init_post_read_processing();
7230         if (err)
7231                 goto out6;
7232
7233         err = ext4_init_pageio();
7234         if (err)
7235                 goto out5;
7236
7237         err = ext4_init_system_zone();
7238         if (err)
7239                 goto out4;
7240
7241         err = ext4_init_sysfs();
7242         if (err)
7243                 goto out3;
7244
7245         err = ext4_init_mballoc();
7246         if (err)
7247                 goto out2;
7248         err = init_inodecache();
7249         if (err)
7250                 goto out1;
7251
7252         err = ext4_fc_init_dentry_cache();
7253         if (err)
7254                 goto out05;
7255
7256         register_as_ext3();
7257         register_as_ext2();
7258         err = register_filesystem(&ext4_fs_type);
7259         if (err)
7260                 goto out;
7261
7262         return 0;
7263 out:
7264         unregister_as_ext2();
7265         unregister_as_ext3();
7266         ext4_fc_destroy_dentry_cache();
7267 out05:
7268         destroy_inodecache();
7269 out1:
7270         ext4_exit_mballoc();
7271 out2:
7272         ext4_exit_sysfs();
7273 out3:
7274         ext4_exit_system_zone();
7275 out4:
7276         ext4_exit_pageio();
7277 out5:
7278         ext4_exit_post_read_processing();
7279 out6:
7280         ext4_exit_pending();
7281 out7:
7282         ext4_exit_es();
7283
7284         return err;
7285 }
7286
7287 static void __exit ext4_exit_fs(void)
7288 {
7289         ext4_destroy_lazyinit_thread();
7290         unregister_as_ext2();
7291         unregister_as_ext3();
7292         unregister_filesystem(&ext4_fs_type);
7293         ext4_fc_destroy_dentry_cache();
7294         destroy_inodecache();
7295         ext4_exit_mballoc();
7296         ext4_exit_sysfs();
7297         ext4_exit_system_zone();
7298         ext4_exit_pageio();
7299         ext4_exit_post_read_processing();
7300         ext4_exit_es();
7301         ext4_exit_pending();
7302 }
7303
7304 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7305 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7306 MODULE_LICENSE("GPL");
7307 MODULE_SOFTDEP("pre: crc32c");
7308 module_init(ext4_init_fs)
7309 module_exit(ext4_exit_fs)