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 folio *folio,
 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 = folio_buffers(folio);
 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                         folio_redirty_for_writepage(wbc, folio);
 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 = ext4_normal_submit_inode_data_buffers(jinode);
 544         return ret;
 545 }
 546
 547 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
 548 {
 549         int ret = 0;
 550
 551         if (!ext4_should_journal_data(jinode->i_vfs_inode))
 552                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
 553
 554         return ret;
 555 }
 556
 557 static bool system_going_down(void)
 558 {
 559         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 560                 || system_state == SYSTEM_RESTART;
 561 }
 562
 563 struct ext4_err_translation {
 564         int code;
 565         int errno;
 566 };
 567
 568 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
 569
 570 static struct ext4_err_translation err_translation[] = {
 571         EXT4_ERR_TRANSLATE(EIO),
 572         EXT4_ERR_TRANSLATE(ENOMEM),
 573         EXT4_ERR_TRANSLATE(EFSBADCRC),
 574         EXT4_ERR_TRANSLATE(EFSCORRUPTED),
 575         EXT4_ERR_TRANSLATE(ENOSPC),
 576         EXT4_ERR_TRANSLATE(ENOKEY),
 577         EXT4_ERR_TRANSLATE(EROFS),
 578         EXT4_ERR_TRANSLATE(EFBIG),
 579         EXT4_ERR_TRANSLATE(EEXIST),
 580         EXT4_ERR_TRANSLATE(ERANGE),
 581         EXT4_ERR_TRANSLATE(EOVERFLOW),
 582         EXT4_ERR_TRANSLATE(EBUSY),
 583         EXT4_ERR_TRANSLATE(ENOTDIR),
 584         EXT4_ERR_TRANSLATE(ENOTEMPTY),
 585         EXT4_ERR_TRANSLATE(ESHUTDOWN),
 586         EXT4_ERR_TRANSLATE(EFAULT),
 587 };
 588
 589 static int ext4_errno_to_code(int errno)
 590 {
 591         int i;
 592
 593         for (i = 0; i < ARRAY_SIZE(err_translation); i++)
 594                 if (err_translation[i].errno == errno)
 595                         return err_translation[i].code;
 596         return EXT4_ERR_UNKNOWN;
 597 }
 598
 599 static void save_error_info(struct super_block *sb, int error,
 600                             __u32 ino, __u64 block,
 601                             const char *func, unsigned int line)
 602 {
 603         struct ext4_sb_info *sbi = EXT4_SB(sb);
 604
 605         /* We default to EFSCORRUPTED error... */
 606         if (error == 0)
 607                 error = EFSCORRUPTED;
 608
 609         spin_lock(&sbi->s_error_lock);
 610         sbi->s_add_error_count++;
 611         sbi->s_last_error_code = error;
 612         sbi->s_last_error_line = line;
 613         sbi->s_last_error_ino = ino;
 614         sbi->s_last_error_block = block;
 615         sbi->s_last_error_func = func;
 616         sbi->s_last_error_time = ktime_get_real_seconds();
 617         if (!sbi->s_first_error_time) {
 618                 sbi->s_first_error_code = error;
 619                 sbi->s_first_error_line = line;
 620                 sbi->s_first_error_ino = ino;
 621                 sbi->s_first_error_block = block;
 622                 sbi->s_first_error_func = func;
 623                 sbi->s_first_error_time = sbi->s_last_error_time;
 624         }
 625         spin_unlock(&sbi->s_error_lock);
 626 }
 627
 628 /* Deal with the reporting of failure conditions on a filesystem such as
 629  * inconsistencies detected or read IO failures.
 630  *
 631  * On ext2, we can store the error state of the filesystem in the
 632  * superblock.  That is not possible on ext4, because we may have other
 633  * write ordering constraints on the superblock which prevent us from
 634  * writing it out straight away; and given that the journal is about to
 635  * be aborted, we can't rely on the current, or future, transactions to
 636  * write out the superblock safely.
 637  *
 638  * We'll just use the jbd2_journal_abort() error code to record an error in
 639  * the journal instead.  On recovery, the journal will complain about
 640  * that error until we've noted it down and cleared it.
 641  *
 642  * If force_ro is set, we unconditionally force the filesystem into an
 643  * ABORT|READONLY state, unless the error response on the fs has been set to
 644  * panic in which case we take the easy way out and panic immediately. This is
 645  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
 646  * at a critical moment in log management.
 647  */
 648 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
 649                               __u32 ino, __u64 block,
 650                               const char *func, unsigned int line)
 651 {
 652         journal_t *journal = EXT4_SB(sb)->s_journal;
 653         bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
 654
 655         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 656         if (test_opt(sb, WARN_ON_ERROR))
 657                 WARN_ON_ONCE(1);
 658
 659         if (!continue_fs && !sb_rdonly(sb)) {
 660                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
 661                 if (journal)
 662                         jbd2_journal_abort(journal, -EIO);
 663         }
 664
 665         if (!bdev_read_only(sb->s_bdev)) {
 666                 save_error_info(sb, error, ino, block, func, line);
 667                 /*
 668                  * In case the fs should keep running, we need to writeout
 669                  * superblock through the journal. Due to lock ordering
 670                  * constraints, it may not be safe to do it right here so we
 671                  * defer superblock flushing to a workqueue.
 672                  */
 673                 if (continue_fs && journal)
 674                         schedule_work(&EXT4_SB(sb)->s_error_work);
 675                 else
 676                         ext4_commit_super(sb);
 677         }
 678
 679         /*
 680          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 681          * could panic during 'reboot -f' as the underlying device got already
 682          * disabled.
 683          */
 684         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 685                 panic("EXT4-fs (device %s): panic forced after error\n",
 686                         sb->s_id);
 687         }
 688
 689         if (sb_rdonly(sb) || continue_fs)
 690                 return;
 691
 692         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 693         /*
 694          * Make sure updated value of ->s_mount_flags will be visible before
 695          * ->s_flags update
 696          */
 697         smp_wmb();
 698         sb->s_flags |= SB_RDONLY;
 699 }
 700
 701 static void flush_stashed_error_work(struct work_struct *work)
 702 {
 703         struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
 704                                                 s_error_work);
 705         journal_t *journal = sbi->s_journal;
 706         handle_t *handle;
 707
 708         /*
 709          * If the journal is still running, we have to write out superblock
 710          * through the journal to avoid collisions of other journalled sb
 711          * updates.
 712          *
 713          * We use directly jbd2 functions here to avoid recursing back into
 714          * ext4 error handling code during handling of previous errors.
 715          */
 716         if (!sb_rdonly(sbi->s_sb) && journal) {
 717                 struct buffer_head *sbh = sbi->s_sbh;
 718                 handle = jbd2_journal_start(journal, 1);
 719                 if (IS_ERR(handle))
 720                         goto write_directly;
 721                 if (jbd2_journal_get_write_access(handle, sbh)) {
 722                         jbd2_journal_stop(handle);
 723                         goto write_directly;
 724                 }
 725                 ext4_update_super(sbi->s_sb);
 726                 if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
 727                         ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
 728                                  "superblock detected");
 729                         clear_buffer_write_io_error(sbh);
 730                         set_buffer_uptodate(sbh);
 731                 }
 732
 733                 if (jbd2_journal_dirty_metadata(handle, sbh)) {
 734                         jbd2_journal_stop(handle);
 735                         goto write_directly;
 736                 }
 737                 jbd2_journal_stop(handle);
 738                 ext4_notify_error_sysfs(sbi);
 739                 return;
 740         }
 741 write_directly:
 742         /*
 743          * Write through journal failed. Write sb directly to get error info
 744          * out and hope for the best.
 745          */
 746         ext4_commit_super(sbi->s_sb);
 747         ext4_notify_error_sysfs(sbi);
 748 }
 749
 750 #define ext4_error_ratelimit(sb)                                        \
 751                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 752                              "EXT4-fs error")
 753
 754 void __ext4_error(struct super_block *sb, const char *function,
 755                   unsigned int line, bool force_ro, int error, __u64 block,
 756                   const char *fmt, ...)
 757 {
 758         struct va_format vaf;
 759         va_list args;
 760
 761         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 762                 return;
 763
 764         trace_ext4_error(sb, function, line);
 765         if (ext4_error_ratelimit(sb)) {
 766                 va_start(args, fmt);
 767                 vaf.fmt = fmt;
 768                 vaf.va = &args;
 769                 printk(KERN_CRIT
 770                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 771                        sb->s_id, function, line, current->comm, &vaf);
 772                 va_end(args);
 773         }
 774         fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
 775
 776         ext4_handle_error(sb, force_ro, error, 0, block, function, line);
 777 }
 778
 779 void __ext4_error_inode(struct inode *inode, const char *function,
 780                         unsigned int line, ext4_fsblk_t block, int error,
 781                         const char *fmt, ...)
 782 {
 783         va_list args;
 784         struct va_format vaf;
 785
 786         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 787                 return;
 788
 789         trace_ext4_error(inode->i_sb, function, line);
 790         if (ext4_error_ratelimit(inode->i_sb)) {
 791                 va_start(args, fmt);
 792                 vaf.fmt = fmt;
 793                 vaf.va = &args;
 794                 if (block)
 795                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 796                                "inode #%lu: block %llu: comm %s: %pV\n",
 797                                inode->i_sb->s_id, function, line, inode->i_ino,
 798                                block, current->comm, &vaf);
 799                 else
 800                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 801                                "inode #%lu: comm %s: %pV\n",
 802                                inode->i_sb->s_id, function, line, inode->i_ino,
 803                                current->comm, &vaf);
 804                 va_end(args);
 805         }
 806         fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
 807
 808         ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
 809                           function, line);
 810 }
 811
 812 void __ext4_error_file(struct file *file, const char *function,
 813                        unsigned int line, ext4_fsblk_t block,
 814                        const char *fmt, ...)
 815 {
 816         va_list args;
 817         struct va_format vaf;
 818         struct inode *inode = file_inode(file);
 819         char pathname[80], *path;
 820
 821         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 822                 return;
 823
 824         trace_ext4_error(inode->i_sb, function, line);
 825         if (ext4_error_ratelimit(inode->i_sb)) {
 826                 path = file_path(file, pathname, sizeof(pathname));
 827                 if (IS_ERR(path))
 828                         path = "(unknown)";
 829                 va_start(args, fmt);
 830                 vaf.fmt = fmt;
 831                 vaf.va = &args;
 832                 if (block)
 833                         printk(KERN_CRIT
 834                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 835                                "block %llu: comm %s: path %s: %pV\n",
 836                                inode->i_sb->s_id, function, line, inode->i_ino,
 837                                block, current->comm, path, &vaf);
 838                 else
 839                         printk(KERN_CRIT
 840                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 841                                "comm %s: path %s: %pV\n",
 842                                inode->i_sb->s_id, function, line, inode->i_ino,
 843                                current->comm, path, &vaf);
 844                 va_end(args);
 845         }
 846         fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
 847
 848         ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
 849                           function, line);
 850 }
 851
 852 const char *ext4_decode_error(struct super_block *sb, int errno,
 853                               char nbuf[16])
 854 {
 855         char *errstr = NULL;
 856
 857         switch (errno) {
 858         case -EFSCORRUPTED:
 859                 errstr = "Corrupt filesystem";
 860                 break;
 861         case -EFSBADCRC:
 862                 errstr = "Filesystem failed CRC";
 863                 break;
 864         case -EIO:
 865                 errstr = "IO failure";
 866                 break;
 867         case -ENOMEM:
 868                 errstr = "Out of memory";
 869                 break;
 870         case -EROFS:
 871                 if (!sb || (EXT4_SB(sb)->s_journal &&
 872                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 873                         errstr = "Journal has aborted";
 874                 else
 875                         errstr = "Readonly filesystem";
 876                 break;
 877         default:
 878                 /* If the caller passed in an extra buffer for unknown
 879                  * errors, textualise them now.  Else we just return
 880                  * NULL. */
 881                 if (nbuf) {
 882                         /* Check for truncated error codes... */
 883                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 884                                 errstr = nbuf;
 885                 }
 886                 break;
 887         }
 888
 889         return errstr;
 890 }
 891
 892 /* __ext4_std_error decodes expected errors from journaling functions
 893  * automatically and invokes the appropriate error response.  */
 894
 895 void __ext4_std_error(struct super_block *sb, const char *function,
 896                       unsigned int line, int errno)
 897 {
 898         char nbuf[16];
 899         const char *errstr;
 900
 901         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 902                 return;
 903
 904         /* Special case: if the error is EROFS, and we're not already
 905          * inside a transaction, then there's really no point in logging
 906          * an error. */
 907         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 908                 return;
 909
 910         if (ext4_error_ratelimit(sb)) {
 911                 errstr = ext4_decode_error(sb, errno, nbuf);
 912                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 913                        sb->s_id, function, line, errstr);
 914         }
 915         fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
 916
 917         ext4_handle_error(sb, false, -errno, 0, 0, function, line);
 918 }
 919
 920 void __ext4_msg(struct super_block *sb,
 921                 const char *prefix, const char *fmt, ...)
 922 {
 923         struct va_format vaf;
 924         va_list args;
 925
 926         if (sb) {
 927                 atomic_inc(&EXT4_SB(sb)->s_msg_count);
 928                 if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state),
 929                                   "EXT4-fs"))
 930                         return;
 931         }
 932
 933         va_start(args, fmt);
 934         vaf.fmt = fmt;
 935         vaf.va = &args;
 936         if (sb)
 937                 printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 938         else
 939                 printk("%sEXT4-fs: %pV\n", prefix, &vaf);
 940         va_end(args);
 941 }
 942
 943 static int ext4_warning_ratelimit(struct super_block *sb)
 944 {
 945         atomic_inc(&EXT4_SB(sb)->s_warning_count);
 946         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
 947                             "EXT4-fs warning");
 948 }
 949
 950 void __ext4_warning(struct super_block *sb, const char *function,
 951                     unsigned int line, const char *fmt, ...)
 952 {
 953         struct va_format vaf;
 954         va_list args;
 955
 956         if (!ext4_warning_ratelimit(sb))
 957                 return;
 958
 959         va_start(args, fmt);
 960         vaf.fmt = fmt;
 961         vaf.va = &args;
 962         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 963                sb->s_id, function, line, &vaf);
 964         va_end(args);
 965 }
 966
 967 void __ext4_warning_inode(const struct inode *inode, const char *function,
 968                           unsigned int line, const char *fmt, ...)
 969 {
 970         struct va_format vaf;
 971         va_list args;
 972
 973         if (!ext4_warning_ratelimit(inode->i_sb))
 974                 return;
 975
 976         va_start(args, fmt);
 977         vaf.fmt = fmt;
 978         vaf.va = &args;
 979         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 980                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 981                function, line, inode->i_ino, current->comm, &vaf);
 982         va_end(args);
 983 }
 984
 985 void __ext4_grp_locked_error(const char *function, unsigned int line,
 986                              struct super_block *sb, ext4_group_t grp,
 987                              unsigned long ino, ext4_fsblk_t block,
 988                              const char *fmt, ...)
 989 __releases(bitlock)
 990 __acquires(bitlock)
 991 {
 992         struct va_format vaf;
 993         va_list args;
 994
 995         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 996                 return;
 997
 998         trace_ext4_error(sb, function, line);
 999         if (ext4_error_ratelimit(sb)) {
1000                 va_start(args, fmt);
1001                 vaf.fmt = fmt;
1002                 vaf.va = &args;
1003                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1004                        sb->s_id, function, line, grp);
1005                 if (ino)
1006                         printk(KERN_CONT "inode %lu: ", ino);
1007                 if (block)
1008                         printk(KERN_CONT "block %llu:",
1009                                (unsigned long long) block);
1010                 printk(KERN_CONT "%pV\n", &vaf);
1011                 va_end(args);
1012         }
1013
1014         if (test_opt(sb, ERRORS_CONT)) {
1015                 if (test_opt(sb, WARN_ON_ERROR))
1016                         WARN_ON_ONCE(1);
1017                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
1018                 if (!bdev_read_only(sb->s_bdev)) {
1019                         save_error_info(sb, EFSCORRUPTED, ino, block, function,
1020                                         line);
1021                         schedule_work(&EXT4_SB(sb)->s_error_work);
1022                 }
1023                 return;
1024         }
1025         ext4_unlock_group(sb, grp);
1026         ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1027         /*
1028          * We only get here in the ERRORS_RO case; relocking the group
1029          * may be dangerous, but nothing bad will happen since the
1030          * filesystem will have already been marked read/only and the
1031          * journal has been aborted.  We return 1 as a hint to callers
1032          * who might what to use the return value from
1033          * ext4_grp_locked_error() to distinguish between the
1034          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1035          * aggressively from the ext4 function in question, with a
1036          * more appropriate error code.
1037          */
1038         ext4_lock_group(sb, grp);
1039         return;
1040 }
1041
1042 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1043                                      ext4_group_t group,
1044                                      unsigned int flags)
1045 {
1046         struct ext4_sb_info *sbi = EXT4_SB(sb);
1047         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1048         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1049         int ret;
1050
1051         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1052                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1053                                             &grp->bb_state);
1054                 if (!ret)
1055                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1056                                            grp->bb_free);
1057         }
1058
1059         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1060                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1061                                             &grp->bb_state);
1062                 if (!ret && gdp) {
1063                         int count;
1064
1065                         count = ext4_free_inodes_count(sb, gdp);
1066                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1067                                            count);
1068                 }
1069         }
1070 }
1071
1072 void ext4_update_dynamic_rev(struct super_block *sb)
1073 {
1074         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1075
1076         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1077                 return;
1078
1079         ext4_warning(sb,
1080                      "updating to rev %d because of new feature flag, "
1081                      "running e2fsck is recommended",
1082                      EXT4_DYNAMIC_REV);
1083
1084         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1085         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1086         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1087         /* leave es->s_feature_*compat flags alone */
1088         /* es->s_uuid will be set by e2fsck if empty */
1089
1090         /*
1091          * The rest of the superblock fields should be zero, and if not it
1092          * means they are likely already in use, so leave them alone.  We
1093          * can leave it up to e2fsck to clean up any inconsistencies there.
1094          */
1095 }
1096
1097 /*
1098  * Open the external journal device
1099  */
1100 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1101 {
1102         struct block_device *bdev;
1103
1104         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1105         if (IS_ERR(bdev))
1106                 goto fail;
1107         return bdev;
1108
1109 fail:
1110         ext4_msg(sb, KERN_ERR,
1111                  "failed to open journal device unknown-block(%u,%u) %ld",
1112                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1113         return NULL;
1114 }
1115
1116 /*
1117  * Release the journal device
1118  */
1119 static void ext4_blkdev_put(struct block_device *bdev)
1120 {
1121         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1122 }
1123
1124 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1125 {
1126         struct block_device *bdev;
1127         bdev = sbi->s_journal_bdev;
1128         if (bdev) {
1129                 ext4_blkdev_put(bdev);
1130                 sbi->s_journal_bdev = NULL;
1131         }
1132 }
1133
1134 static inline struct inode *orphan_list_entry(struct list_head *l)
1135 {
1136         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1137 }
1138
1139 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1140 {
1141         struct list_head *l;
1142
1143         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1144                  le32_to_cpu(sbi->s_es->s_last_orphan));
1145
1146         printk(KERN_ERR "sb_info orphan list:\n");
1147         list_for_each(l, &sbi->s_orphan) {
1148                 struct inode *inode = orphan_list_entry(l);
1149                 printk(KERN_ERR "  "
1150                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1151                        inode->i_sb->s_id, inode->i_ino, inode,
1152                        inode->i_mode, inode->i_nlink,
1153                        NEXT_ORPHAN(inode));
1154         }
1155 }
1156
1157 #ifdef CONFIG_QUOTA
1158 static int ext4_quota_off(struct super_block *sb, int type);
1159
1160 static inline void ext4_quota_off_umount(struct super_block *sb)
1161 {
1162         int type;
1163
1164         /* Use our quota_off function to clear inode flags etc. */
1165         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1166                 ext4_quota_off(sb, type);
1167 }
1168
1169 /*
1170  * This is a helper function which is used in the mount/remount
1171  * codepaths (which holds s_umount) to fetch the quota file name.
1172  */
1173 static inline char *get_qf_name(struct super_block *sb,
1174                                 struct ext4_sb_info *sbi,
1175                                 int type)
1176 {
1177         return rcu_dereference_protected(sbi->s_qf_names[type],
1178                                          lockdep_is_held(&sb->s_umount));
1179 }
1180 #else
1181 static inline void ext4_quota_off_umount(struct super_block *sb)
1182 {
1183 }
1184 #endif
1185
1186 static void ext4_put_super(struct super_block *sb)
1187 {
1188         struct ext4_sb_info *sbi = EXT4_SB(sb);
1189         struct ext4_super_block *es = sbi->s_es;
1190         struct buffer_head **group_desc;
1191         struct flex_groups **flex_groups;
1192         int aborted = 0;
1193         int i, err;
1194
1195         /*
1196          * Unregister sysfs before destroying jbd2 journal.
1197          * Since we could still access attr_journal_task attribute via sysfs
1198          * path which could have sbi->s_journal->j_task as NULL
1199          * Unregister sysfs before flush sbi->s_error_work.
1200          * Since user may read /proc/fs/ext4/xx/mb_groups during umount, If
1201          * read metadata verify failed then will queue error work.
1202          * flush_stashed_error_work will call start_this_handle may trigger
1203          * BUG_ON.
1204          */
1205         ext4_unregister_sysfs(sb);
1206
1207         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs unmount"))
1208                 ext4_msg(sb, KERN_INFO, "unmounting filesystem %pU.",
1209                          &sb->s_uuid);
1210
1211         ext4_unregister_li_request(sb);
1212         ext4_quota_off_umount(sb);
1213
1214         flush_work(&sbi->s_error_work);
1215         destroy_workqueue(sbi->rsv_conversion_wq);
1216         ext4_release_orphan_info(sb);
1217
1218         if (sbi->s_journal) {
1219                 aborted = is_journal_aborted(sbi->s_journal);
1220                 err = jbd2_journal_destroy(sbi->s_journal);
1221                 sbi->s_journal = NULL;
1222                 if ((err < 0) && !aborted) {
1223                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1224                 }
1225         }
1226
1227         ext4_es_unregister_shrinker(sbi);
1228         timer_shutdown_sync(&sbi->s_err_report);
1229         ext4_release_system_zone(sb);
1230         ext4_mb_release(sb);
1231         ext4_ext_release(sb);
1232
1233         if (!sb_rdonly(sb) && !aborted) {
1234                 ext4_clear_feature_journal_needs_recovery(sb);
1235                 ext4_clear_feature_orphan_present(sb);
1236                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1237         }
1238         if (!sb_rdonly(sb))
1239                 ext4_commit_super(sb);
1240
1241         rcu_read_lock();
1242         group_desc = rcu_dereference(sbi->s_group_desc);
1243         for (i = 0; i < sbi->s_gdb_count; i++)
1244                 brelse(group_desc[i]);
1245         kvfree(group_desc);
1246         flex_groups = rcu_dereference(sbi->s_flex_groups);
1247         if (flex_groups) {
1248                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1249                         kvfree(flex_groups[i]);
1250                 kvfree(flex_groups);
1251         }
1252         rcu_read_unlock();
1253         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1254         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1255         percpu_counter_destroy(&sbi->s_dirs_counter);
1256         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1257         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1258         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1259 #ifdef CONFIG_QUOTA
1260         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1261                 kfree(get_qf_name(sb, sbi, i));
1262 #endif
1263
1264         /* Debugging code just in case the in-memory inode orphan list
1265          * isn't empty.  The on-disk one can be non-empty if we've
1266          * detected an error and taken the fs readonly, but the
1267          * in-memory list had better be clean by this point. */
1268         if (!list_empty(&sbi->s_orphan))
1269                 dump_orphan_list(sb, sbi);
1270         ASSERT(list_empty(&sbi->s_orphan));
1271
1272         sync_blockdev(sb->s_bdev);
1273         invalidate_bdev(sb->s_bdev);
1274         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1275                 /*
1276                  * Invalidate the journal device's buffers.  We don't want them
1277                  * floating about in memory - the physical journal device may
1278                  * hotswapped, and it breaks the `ro-after' testing code.
1279                  */
1280                 sync_blockdev(sbi->s_journal_bdev);
1281                 invalidate_bdev(sbi->s_journal_bdev);
1282                 ext4_blkdev_remove(sbi);
1283         }
1284
1285         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1286         sbi->s_ea_inode_cache = NULL;
1287
1288         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1289         sbi->s_ea_block_cache = NULL;
1290
1291         ext4_stop_mmpd(sbi);
1292
1293         brelse(sbi->s_sbh);
1294         sb->s_fs_info = NULL;
1295         /*
1296          * Now that we are completely done shutting down the
1297          * superblock, we need to actually destroy the kobject.
1298          */
1299         kobject_put(&sbi->s_kobj);
1300         wait_for_completion(&sbi->s_kobj_unregister);
1301         if (sbi->s_chksum_driver)
1302                 crypto_free_shash(sbi->s_chksum_driver);
1303         kfree(sbi->s_blockgroup_lock);
1304         fs_put_dax(sbi->s_daxdev, NULL);
1305         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1306 #if IS_ENABLED(CONFIG_UNICODE)
1307         utf8_unload(sb->s_encoding);
1308 #endif
1309         kfree(sbi);
1310 }
1311
1312 static struct kmem_cache *ext4_inode_cachep;
1313
1314 /*
1315  * Called inside transaction, so use GFP_NOFS
1316  */
1317 static struct inode *ext4_alloc_inode(struct super_block *sb)
1318 {
1319         struct ext4_inode_info *ei;
1320
1321         ei = alloc_inode_sb(sb, ext4_inode_cachep, GFP_NOFS);
1322         if (!ei)
1323                 return NULL;
1324
1325         inode_set_iversion(&ei->vfs_inode, 1);
1326         ei->i_flags = 0;
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
2639         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy))
2640                 return 0;
2641
2642         if (!ext4_has_feature_encrypt(sb)) {
2643                 ext4_msg(NULL, KERN_WARNING,
2644                          "test_dummy_encryption requires encrypt feature");
2645                 return -EINVAL;
2646         }
2647         /*
2648          * This mount option is just for testing, and it's not worthwhile to
2649          * implement the extra complexity (e.g. RCU protection) that would be
2650          * needed to allow it to be set or changed during remount.  We do allow
2651          * it to be specified during remount, but only if there is no change.
2652          */
2653         if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2654                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2655                                                  &ctx->dummy_enc_policy))
2656                         return 0;
2657                 ext4_msg(NULL, KERN_WARNING,
2658                          "Can't set or change test_dummy_encryption on remount");
2659                 return -EINVAL;
2660         }
2661         /* Also make sure s_mount_opts didn't contain a conflicting value. */
2662         if (fscrypt_is_dummy_policy_set(&sbi->s_dummy_enc_policy)) {
2663                 if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2664                                                  &ctx->dummy_enc_policy))
2665                         return 0;
2666                 ext4_msg(NULL, KERN_WARNING,
2667                          "Conflicting test_dummy_encryption options");
2668                 return -EINVAL;
2669         }
2670         return 0;
2671 }
2672
2673 static void ext4_apply_test_dummy_encryption(struct ext4_fs_context *ctx,
2674                                              struct super_block *sb)
2675 {
2676         if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy) ||
2677             /* if already set, it was already verified to be the same */
2678             fscrypt_is_dummy_policy_set(&EXT4_SB(sb)->s_dummy_enc_policy))
2679                 return;
2680         EXT4_SB(sb)->s_dummy_enc_policy = ctx->dummy_enc_policy;
2681         memset(&ctx->dummy_enc_policy, 0, sizeof(ctx->dummy_enc_policy));
2682         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2683 }
2684
2685 static int ext4_check_opt_consistency(struct fs_context *fc,
2686                                       struct super_block *sb)
2687 {
2688         struct ext4_fs_context *ctx = fc->fs_private;
2689         struct ext4_sb_info *sbi = fc->s_fs_info;
2690         int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2691         int err;
2692
2693         if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2694                 ext4_msg(NULL, KERN_ERR,
2695                          "Mount option(s) incompatible with ext2");
2696                 return -EINVAL;
2697         }
2698         if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2699                 ext4_msg(NULL, KERN_ERR,
2700                          "Mount option(s) incompatible with ext3");
2701                 return -EINVAL;
2702         }
2703
2704         if (ctx->s_want_extra_isize >
2705             (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2706                 ext4_msg(NULL, KERN_ERR,
2707                          "Invalid want_extra_isize %d",
2708                          ctx->s_want_extra_isize);
2709                 return -EINVAL;
2710         }
2711
2712         if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DIOREAD_NOLOCK)) {
2713                 int blocksize =
2714                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2715                 if (blocksize < PAGE_SIZE)
2716                         ext4_msg(NULL, KERN_WARNING, "Warning: mounting with an "
2717                                  "experimental mount option 'dioread_nolock' "
2718                                  "for blocksize < PAGE_SIZE");
2719         }
2720
2721         err = ext4_check_test_dummy_encryption(fc, sb);
2722         if (err)
2723                 return err;
2724
2725         if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2726                 if (!sbi->s_journal) {
2727                         ext4_msg(NULL, KERN_WARNING,
2728                                  "Remounting file system with no journal "
2729                                  "so ignoring journalled data option");
2730                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2731                 } else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2732                            test_opt(sb, DATA_FLAGS)) {
2733                         ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2734                                  "on remount");
2735                         return -EINVAL;
2736                 }
2737         }
2738
2739         if (is_remount) {
2740                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2741                     (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2742                         ext4_msg(NULL, KERN_ERR, "can't mount with "
2743                                  "both data=journal and dax");
2744                         return -EINVAL;
2745                 }
2746
2747                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2748                     (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2749                      (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2750 fail_dax_change_remount:
2751                         ext4_msg(NULL, KERN_ERR, "can't change "
2752                                  "dax mount option while remounting");
2753                         return -EINVAL;
2754                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2755                          (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2756                           (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2757                         goto fail_dax_change_remount;
2758                 } else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2759                            ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2760                             (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2761                             !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2762                         goto fail_dax_change_remount;
2763                 }
2764         }
2765
2766         return ext4_check_quota_consistency(fc, sb);
2767 }
2768
2769 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2770 {
2771         struct ext4_fs_context *ctx = fc->fs_private;
2772         struct ext4_sb_info *sbi = fc->s_fs_info;
2773
2774         sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2775         sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2776         sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2777         sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2778         sbi->s_mount_flags &= ~ctx->mask_s_mount_flags;
2779         sbi->s_mount_flags |= ctx->vals_s_mount_flags;
2780         sb->s_flags &= ~ctx->mask_s_flags;
2781         sb->s_flags |= ctx->vals_s_flags;
2782
2783 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2784         APPLY(s_commit_interval);
2785         APPLY(s_stripe);
2786         APPLY(s_max_batch_time);
2787         APPLY(s_min_batch_time);
2788         APPLY(s_want_extra_isize);
2789         APPLY(s_inode_readahead_blks);
2790         APPLY(s_max_dir_size_kb);
2791         APPLY(s_li_wait_mult);
2792         APPLY(s_resgid);
2793         APPLY(s_resuid);
2794
2795 #ifdef CONFIG_EXT4_DEBUG
2796         APPLY(s_fc_debug_max_replay);
2797 #endif
2798
2799         ext4_apply_quota_options(fc, sb);
2800         ext4_apply_test_dummy_encryption(ctx, sb);
2801 }
2802
2803
2804 static int ext4_validate_options(struct fs_context *fc)
2805 {
2806 #ifdef CONFIG_QUOTA
2807         struct ext4_fs_context *ctx = fc->fs_private;
2808         char *usr_qf_name, *grp_qf_name;
2809
2810         usr_qf_name = ctx->s_qf_names[USRQUOTA];
2811         grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2812
2813         if (usr_qf_name || grp_qf_name) {
2814                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2815                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2816
2817                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2818                         ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2819
2820                 if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2821                     ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2822                         ext4_msg(NULL, KERN_ERR, "old and new quota "
2823                                  "format mixing");
2824                         return -EINVAL;
2825                 }
2826         }
2827 #endif
2828         return 1;
2829 }
2830
2831 static inline void ext4_show_quota_options(struct seq_file *seq,
2832                                            struct super_block *sb)
2833 {
2834 #if defined(CONFIG_QUOTA)
2835         struct ext4_sb_info *sbi = EXT4_SB(sb);
2836         char *usr_qf_name, *grp_qf_name;
2837
2838         if (sbi->s_jquota_fmt) {
2839                 char *fmtname = "";
2840
2841                 switch (sbi->s_jquota_fmt) {
2842                 case QFMT_VFS_OLD:
2843                         fmtname = "vfsold";
2844                         break;
2845                 case QFMT_VFS_V0:
2846                         fmtname = "vfsv0";
2847                         break;
2848                 case QFMT_VFS_V1:
2849                         fmtname = "vfsv1";
2850                         break;
2851                 }
2852                 seq_printf(seq, ",jqfmt=%s", fmtname);
2853         }
2854
2855         rcu_read_lock();
2856         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2857         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2858         if (usr_qf_name)
2859                 seq_show_option(seq, "usrjquota", usr_qf_name);
2860         if (grp_qf_name)
2861                 seq_show_option(seq, "grpjquota", grp_qf_name);
2862         rcu_read_unlock();
2863 #endif
2864 }
2865
2866 static const char *token2str(int token)
2867 {
2868         const struct fs_parameter_spec *spec;
2869
2870         for (spec = ext4_param_specs; spec->name != NULL; spec++)
2871                 if (spec->opt == token && !spec->type)
2872                         break;
2873         return spec->name;
2874 }
2875
2876 /*
2877  * Show an option if
2878  *  - it's set to a non-default value OR
2879  *  - if the per-sb default is different from the global default
2880  */
2881 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2882                               int nodefs)
2883 {
2884         struct ext4_sb_info *sbi = EXT4_SB(sb);
2885         struct ext4_super_block *es = sbi->s_es;
2886         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2887         const struct mount_opts *m;
2888         char sep = nodefs ? '\n' : ',';
2889
2890 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2891 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2892
2893         if (sbi->s_sb_block != 1)
2894                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2895
2896         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2897                 int want_set = m->flags & MOPT_SET;
2898                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2899                     m->flags & MOPT_SKIP)
2900                         continue;
2901                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2902                         continue; /* skip if same as the default */
2903                 if ((want_set &&
2904                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2905                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2906                         continue; /* select Opt_noFoo vs Opt_Foo */
2907                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2908         }
2909
2910         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2911             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2912                 SEQ_OPTS_PRINT("resuid=%u",
2913                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2914         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2915             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2916                 SEQ_OPTS_PRINT("resgid=%u",
2917                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2918         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2919         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2920                 SEQ_OPTS_PUTS("errors=remount-ro");
2921         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2922                 SEQ_OPTS_PUTS("errors=continue");
2923         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2924                 SEQ_OPTS_PUTS("errors=panic");
2925         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2926                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2927         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2928                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2929         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2930                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2931         if (nodefs || sbi->s_stripe)
2932                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2933         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2934                         (sbi->s_mount_opt ^ def_mount_opt)) {
2935                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2936                         SEQ_OPTS_PUTS("data=journal");
2937                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2938                         SEQ_OPTS_PUTS("data=ordered");
2939                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2940                         SEQ_OPTS_PUTS("data=writeback");
2941         }
2942         if (nodefs ||
2943             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2944                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2945                                sbi->s_inode_readahead_blks);
2946
2947         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2948                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2949                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2950         if (nodefs || sbi->s_max_dir_size_kb)
2951                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2952         if (test_opt(sb, DATA_ERR_ABORT))
2953                 SEQ_OPTS_PUTS("data_err=abort");
2954
2955         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2956
2957         if (sb->s_flags & SB_INLINECRYPT)
2958                 SEQ_OPTS_PUTS("inlinecrypt");
2959
2960         if (test_opt(sb, DAX_ALWAYS)) {
2961                 if (IS_EXT2_SB(sb))
2962                         SEQ_OPTS_PUTS("dax");
2963                 else
2964                         SEQ_OPTS_PUTS("dax=always");
2965         } else if (test_opt2(sb, DAX_NEVER)) {
2966                 SEQ_OPTS_PUTS("dax=never");
2967         } else if (test_opt2(sb, DAX_INODE)) {
2968                 SEQ_OPTS_PUTS("dax=inode");
2969         }
2970
2971         if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
2972                         !test_opt2(sb, MB_OPTIMIZE_SCAN)) {
2973                 SEQ_OPTS_PUTS("mb_optimize_scan=0");
2974         } else if (sbi->s_groups_count < MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
2975                         test_opt2(sb, MB_OPTIMIZE_SCAN)) {
2976                 SEQ_OPTS_PUTS("mb_optimize_scan=1");
2977         }
2978
2979         ext4_show_quota_options(seq, sb);
2980         return 0;
2981 }
2982
2983 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2984 {
2985         return _ext4_show_options(seq, root->d_sb, 0);
2986 }
2987
2988 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2989 {
2990         struct super_block *sb = seq->private;
2991         int rc;
2992
2993         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2994         rc = _ext4_show_options(seq, sb, 1);
2995         seq_puts(seq, "\n");
2996         return rc;
2997 }
2998
2999 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3000                             int read_only)
3001 {
3002         struct ext4_sb_info *sbi = EXT4_SB(sb);
3003         int err = 0;
3004
3005         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3006                 ext4_msg(sb, KERN_ERR, "revision level too high, "
3007                          "forcing read-only mode");
3008                 err = -EROFS;
3009                 goto done;
3010         }
3011         if (read_only)
3012                 goto done;
3013         if (!(sbi->s_mount_state & EXT4_VALID_FS))
3014                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3015                          "running e2fsck is recommended");
3016         else if (sbi->s_mount_state & EXT4_ERROR_FS)
3017                 ext4_msg(sb, KERN_WARNING,
3018                          "warning: mounting fs with errors, "
3019                          "running e2fsck is recommended");
3020         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3021                  le16_to_cpu(es->s_mnt_count) >=
3022                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3023                 ext4_msg(sb, KERN_WARNING,
3024                          "warning: maximal mount count reached, "
3025                          "running e2fsck is recommended");
3026         else if (le32_to_cpu(es->s_checkinterval) &&
3027                  (ext4_get_tstamp(es, s_lastcheck) +
3028                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3029                 ext4_msg(sb, KERN_WARNING,
3030                          "warning: checktime reached, "
3031                          "running e2fsck is recommended");
3032         if (!sbi->s_journal)
3033                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3034         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3035                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3036         le16_add_cpu(&es->s_mnt_count, 1);
3037         ext4_update_tstamp(es, s_mtime);
3038         if (sbi->s_journal) {
3039                 ext4_set_feature_journal_needs_recovery(sb);
3040                 if (ext4_has_feature_orphan_file(sb))
3041                         ext4_set_feature_orphan_present(sb);
3042         }
3043
3044         err = ext4_commit_super(sb);
3045 done:
3046         if (test_opt(sb, DEBUG))
3047                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3048                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3049                         sb->s_blocksize,
3050                         sbi->s_groups_count,
3051                         EXT4_BLOCKS_PER_GROUP(sb),
3052                         EXT4_INODES_PER_GROUP(sb),
3053                         sbi->s_mount_opt, sbi->s_mount_opt2);
3054         return err;
3055 }
3056
3057 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3058 {
3059         struct ext4_sb_info *sbi = EXT4_SB(sb);
3060         struct flex_groups **old_groups, **new_groups;
3061         int size, i, j;
3062
3063         if (!sbi->s_log_groups_per_flex)
3064                 return 0;
3065
3066         size = ext4_flex_group(sbi, ngroup - 1) + 1;
3067         if (size <= sbi->s_flex_groups_allocated)
3068                 return 0;
3069
3070         new_groups = kvzalloc(roundup_pow_of_two(size *
3071                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3072         if (!new_groups) {
3073                 ext4_msg(sb, KERN_ERR,
3074                          "not enough memory for %d flex group pointers", size);
3075                 return -ENOMEM;
3076         }
3077         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3078                 new_groups[i] = kvzalloc(roundup_pow_of_two(
3079                                          sizeof(struct flex_groups)),
3080                                          GFP_KERNEL);
3081                 if (!new_groups[i]) {
3082                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
3083                                 kvfree(new_groups[j]);
3084                         kvfree(new_groups);
3085                         ext4_msg(sb, KERN_ERR,
3086                                  "not enough memory for %d flex groups", size);
3087                         return -ENOMEM;
3088                 }
3089         }
3090         rcu_read_lock();
3091         old_groups = rcu_dereference(sbi->s_flex_groups);
3092         if (old_groups)
3093                 memcpy(new_groups, old_groups,
3094                        (sbi->s_flex_groups_allocated *
3095                         sizeof(struct flex_groups *)));
3096         rcu_read_unlock();
3097         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3098         sbi->s_flex_groups_allocated = size;
3099         if (old_groups)
3100                 ext4_kvfree_array_rcu(old_groups);
3101         return 0;
3102 }
3103
3104 static int ext4_fill_flex_info(struct super_block *sb)
3105 {
3106         struct ext4_sb_info *sbi = EXT4_SB(sb);
3107         struct ext4_group_desc *gdp = NULL;
3108         struct flex_groups *fg;
3109         ext4_group_t flex_group;
3110         int i, err;
3111
3112         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3113         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3114                 sbi->s_log_groups_per_flex = 0;
3115                 return 1;
3116         }
3117
3118         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3119         if (err)
3120                 goto failed;
3121
3122         for (i = 0; i < sbi->s_groups_count; i++) {
3123                 gdp = ext4_get_group_desc(sb, i, NULL);
3124
3125                 flex_group = ext4_flex_group(sbi, i);
3126                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3127                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3128                 atomic64_add(ext4_free_group_clusters(sb, gdp),
3129                              &fg->free_clusters);
3130                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3131         }
3132
3133         return 1;
3134 failed:
3135         return 0;
3136 }
3137
3138 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3139                                    struct ext4_group_desc *gdp)
3140 {
3141         int offset = offsetof(struct ext4_group_desc, bg_checksum);
3142         __u16 crc = 0;
3143         __le32 le_group = cpu_to_le32(block_group);
3144         struct ext4_sb_info *sbi = EXT4_SB(sb);
3145
3146         if (ext4_has_metadata_csum(sbi->s_sb)) {
3147                 /* Use new metadata_csum algorithm */
3148                 __u32 csum32;
3149                 __u16 dummy_csum = 0;
3150
3151                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
3152                                      sizeof(le_group));
3153                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
3154                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
3155                                      sizeof(dummy_csum));
3156                 offset += sizeof(dummy_csum);
3157                 if (offset < sbi->s_desc_size)
3158                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
3159                                              sbi->s_desc_size - offset);
3160
3161                 crc = csum32 & 0xFFFF;
3162                 goto out;
3163         }
3164
3165         /* old crc16 code */
3166         if (!ext4_has_feature_gdt_csum(sb))
3167                 return 0;
3168
3169         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3170         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3171         crc = crc16(crc, (__u8 *)gdp, offset);
3172         offset += sizeof(gdp->bg_checksum); /* skip checksum */
3173         /* for checksum of struct ext4_group_desc do the rest...*/
3174         if (ext4_has_feature_64bit(sb) &&
3175             offset < le16_to_cpu(sbi->s_es->s_desc_size))
3176                 crc = crc16(crc, (__u8 *)gdp + offset,
3177                             le16_to_cpu(sbi->s_es->s_desc_size) -
3178                                 offset);
3179
3180 out:
3181         return cpu_to_le16(crc);
3182 }
3183
3184 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3185                                 struct ext4_group_desc *gdp)
3186 {
3187         if (ext4_has_group_desc_csum(sb) &&
3188             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3189                 return 0;
3190
3191         return 1;
3192 }
3193
3194 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3195                               struct ext4_group_desc *gdp)
3196 {
3197         if (!ext4_has_group_desc_csum(sb))
3198                 return;
3199         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3200 }
3201
3202 /* Called at mount-time, super-block is locked */
3203 static int ext4_check_descriptors(struct super_block *sb,
3204                                   ext4_fsblk_t sb_block,
3205                                   ext4_group_t *first_not_zeroed)
3206 {
3207         struct ext4_sb_info *sbi = EXT4_SB(sb);
3208         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3209         ext4_fsblk_t last_block;
3210         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3211         ext4_fsblk_t block_bitmap;
3212         ext4_fsblk_t inode_bitmap;
3213         ext4_fsblk_t inode_table;
3214         int flexbg_flag = 0;
3215         ext4_group_t i, grp = sbi->s_groups_count;
3216
3217         if (ext4_has_feature_flex_bg(sb))
3218                 flexbg_flag = 1;
3219
3220         ext4_debug("Checking group descriptors");
3221
3222         for (i = 0; i < sbi->s_groups_count; i++) {
3223                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3224
3225                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
3226                         last_block = ext4_blocks_count(sbi->s_es) - 1;
3227                 else
3228                         last_block = first_block +
3229                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
3230
3231                 if ((grp == sbi->s_groups_count) &&
3232                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3233                         grp = i;
3234
3235                 block_bitmap = ext4_block_bitmap(sb, gdp);
3236                 if (block_bitmap == sb_block) {
3237                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3238                                  "Block bitmap for group %u overlaps "
3239                                  "superblock", i);
3240                         if (!sb_rdonly(sb))
3241                                 return 0;
3242                 }
3243                 if (block_bitmap >= sb_block + 1 &&
3244                     block_bitmap <= last_bg_block) {
3245                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3246                                  "Block bitmap for group %u overlaps "
3247                                  "block group descriptors", i);
3248                         if (!sb_rdonly(sb))
3249                                 return 0;
3250                 }
3251                 if (block_bitmap < first_block || block_bitmap > last_block) {
3252                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3253                                "Block bitmap for group %u not in group "
3254                                "(block %llu)!", i, block_bitmap);
3255                         return 0;
3256                 }
3257                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
3258                 if (inode_bitmap == sb_block) {
3259                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3260                                  "Inode bitmap for group %u overlaps "
3261                                  "superblock", i);
3262                         if (!sb_rdonly(sb))
3263                                 return 0;
3264                 }
3265                 if (inode_bitmap >= sb_block + 1 &&
3266                     inode_bitmap <= last_bg_block) {
3267                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3268                                  "Inode bitmap for group %u overlaps "
3269                                  "block group descriptors", i);
3270                         if (!sb_rdonly(sb))
3271                                 return 0;
3272                 }
3273                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
3274                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3275                                "Inode bitmap for group %u not in group "
3276                                "(block %llu)!", i, inode_bitmap);
3277                         return 0;
3278                 }
3279                 inode_table = ext4_inode_table(sb, gdp);
3280                 if (inode_table == sb_block) {
3281                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3282                                  "Inode table for group %u overlaps "
3283                                  "superblock", i);
3284                         if (!sb_rdonly(sb))
3285                                 return 0;
3286                 }
3287                 if (inode_table >= sb_block + 1 &&
3288                     inode_table <= last_bg_block) {
3289                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3290                                  "Inode table for group %u overlaps "
3291                                  "block group descriptors", i);
3292                         if (!sb_rdonly(sb))
3293                                 return 0;
3294                 }
3295                 if (inode_table < first_block ||
3296                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
3297                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3298                                "Inode table for group %u not in group "
3299                                "(block %llu)!", i, inode_table);
3300                         return 0;
3301                 }
3302                 ext4_lock_group(sb, i);
3303                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3304                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3305                                  "Checksum for group %u failed (%u!=%u)",
3306                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3307                                      gdp)), le16_to_cpu(gdp->bg_checksum));
3308                         if (!sb_rdonly(sb)) {
3309                                 ext4_unlock_group(sb, i);
3310                                 return 0;
3311                         }
3312                 }
3313                 ext4_unlock_group(sb, i);
3314                 if (!flexbg_flag)
3315                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
3316         }
3317         if (NULL != first_not_zeroed)
3318                 *first_not_zeroed = grp;
3319         return 1;
3320 }
3321
3322 /*
3323  * Maximal extent format file size.
3324  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3325  * extent format containers, within a sector_t, and within i_blocks
3326  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3327  * so that won't be a limiting factor.
3328  *
3329  * However there is other limiting factor. We do store extents in the form
3330  * of starting block and length, hence the resulting length of the extent
3331  * covering maximum file size must fit into on-disk format containers as
3332  * well. Given that length is always by 1 unit bigger than max unit (because
3333  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3334  *
3335  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3336  */
3337 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3338 {
3339         loff_t res;
3340         loff_t upper_limit = MAX_LFS_FILESIZE;
3341
3342         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3343
3344         if (!has_huge_files) {
3345                 upper_limit = (1LL << 32) - 1;
3346
3347                 /* total blocks in file system block size */
3348                 upper_limit >>= (blkbits - 9);
3349                 upper_limit <<= blkbits;
3350         }
3351
3352         /*
3353          * 32-bit extent-start container, ee_block. We lower the maxbytes
3354          * by one fs block, so ee_len can cover the extent of maximum file
3355          * size
3356          */
3357         res = (1LL << 32) - 1;
3358         res <<= blkbits;
3359
3360         /* Sanity check against vm- & vfs- imposed limits */
3361         if (res > upper_limit)
3362                 res = upper_limit;
3363
3364         return res;
3365 }
3366
3367 /*
3368  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3369  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3370  * We need to be 1 filesystem block less than the 2^48 sector limit.
3371  */
3372 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3373 {
3374         loff_t upper_limit, res = EXT4_NDIR_BLOCKS;
3375         int meta_blocks;
3376         unsigned int ppb = 1 << (bits - 2);
3377
3378         /*
3379          * This is calculated to be the largest file size for a dense, block
3380          * mapped file such that the file's total number of 512-byte sectors,
3381          * including data and all indirect blocks, does not exceed (2^48 - 1).
3382          *
3383          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3384          * number of 512-byte sectors of the file.
3385          */
3386         if (!has_huge_files) {
3387                 /*
3388                  * !has_huge_files or implies that the inode i_block field
3389                  * represents total file blocks in 2^32 512-byte sectors ==
3390                  * size of vfs inode i_blocks * 8
3391                  */
3392                 upper_limit = (1LL << 32) - 1;
3393
3394                 /* total blocks in file system block size */
3395                 upper_limit >>= (bits - 9);
3396
3397         } else {
3398                 /*
3399                  * We use 48 bit ext4_inode i_blocks
3400                  * With EXT4_HUGE_FILE_FL set the i_blocks
3401                  * represent total number of blocks in
3402                  * file system block size
3403                  */
3404                 upper_limit = (1LL << 48) - 1;
3405
3406         }
3407
3408         /* Compute how many blocks we can address by block tree */
3409         res += ppb;
3410         res += ppb * ppb;
3411         res += ((loff_t)ppb) * ppb * ppb;
3412         /* Compute how many metadata blocks are needed */
3413         meta_blocks = 1;
3414         meta_blocks += 1 + ppb;
3415         meta_blocks += 1 + ppb + ppb * ppb;
3416         /* Does block tree limit file size? */
3417         if (res + meta_blocks <= upper_limit)
3418                 goto check_lfs;
3419
3420         res = upper_limit;
3421         /* How many metadata blocks are needed for addressing upper_limit? */
3422         upper_limit -= EXT4_NDIR_BLOCKS;
3423         /* indirect blocks */
3424         meta_blocks = 1;
3425         upper_limit -= ppb;
3426         /* double indirect blocks */
3427         if (upper_limit < ppb * ppb) {
3428                 meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb);
3429                 res -= meta_blocks;
3430                 goto check_lfs;
3431         }
3432         meta_blocks += 1 + ppb;
3433         upper_limit -= ppb * ppb;
3434         /* tripple indirect blocks for the rest */
3435         meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb) +
3436                 DIV_ROUND_UP_ULL(upper_limit, ppb*ppb);
3437         res -= meta_blocks;
3438 check_lfs:
3439         res <<= bits;
3440         if (res > MAX_LFS_FILESIZE)
3441                 res = MAX_LFS_FILESIZE;
3442
3443         return res;
3444 }
3445
3446 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3447                                    ext4_fsblk_t logical_sb_block, int nr)
3448 {
3449         struct ext4_sb_info *sbi = EXT4_SB(sb);
3450         ext4_group_t bg, first_meta_bg;
3451         int has_super = 0;
3452
3453         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3454
3455         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3456                 return logical_sb_block + nr + 1;
3457         bg = sbi->s_desc_per_block * nr;
3458         if (ext4_bg_has_super(sb, bg))
3459                 has_super = 1;
3460
3461         /*
3462          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3463          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3464          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3465          * compensate.
3466          */
3467         if (sb->s_blocksize == 1024 && nr == 0 &&
3468             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3469                 has_super++;
3470
3471         return (has_super + ext4_group_first_block_no(sb, bg));
3472 }
3473
3474 /**
3475  * ext4_get_stripe_size: Get the stripe size.
3476  * @sbi: In memory super block info
3477  *
3478  * If we have specified it via mount option, then
3479  * use the mount option value. If the value specified at mount time is
3480  * greater than the blocks per group use the super block value.
3481  * If the super block value is greater than blocks per group return 0.
3482  * Allocator needs it be less than blocks per group.
3483  *
3484  */
3485 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3486 {
3487         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3488         unsigned long stripe_width =
3489                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3490         int ret;
3491
3492         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3493                 ret = sbi->s_stripe;
3494         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3495                 ret = stripe_width;
3496         else if (stride && stride <= sbi->s_blocks_per_group)
3497                 ret = stride;
3498         else
3499                 ret = 0;
3500
3501         /*
3502          * If the stripe width is 1, this makes no sense and
3503          * we set it to 0 to turn off stripe handling code.
3504          */
3505         if (ret <= 1)
3506                 ret = 0;
3507
3508         return ret;
3509 }
3510
3511 /*
3512  * Check whether this filesystem can be mounted based on
3513  * the features present and the RDONLY/RDWR mount requested.
3514  * Returns 1 if this filesystem can be mounted as requested,
3515  * 0 if it cannot be.
3516  */
3517 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3518 {
3519         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3520                 ext4_msg(sb, KERN_ERR,
3521                         "Couldn't mount because of "
3522                         "unsupported optional features (%x)",
3523                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3524                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3525                 return 0;
3526         }
3527
3528 #if !IS_ENABLED(CONFIG_UNICODE)
3529         if (ext4_has_feature_casefold(sb)) {
3530                 ext4_msg(sb, KERN_ERR,
3531                          "Filesystem with casefold feature cannot be "
3532                          "mounted without CONFIG_UNICODE");
3533                 return 0;
3534         }
3535 #endif
3536
3537         if (readonly)
3538                 return 1;
3539
3540         if (ext4_has_feature_readonly(sb)) {
3541                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3542                 sb->s_flags |= SB_RDONLY;
3543                 return 1;
3544         }
3545
3546         /* Check that feature set is OK for a read-write mount */
3547         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3548                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3549                          "unsupported optional features (%x)",
3550                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3551                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3552                 return 0;
3553         }
3554         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3555                 ext4_msg(sb, KERN_ERR,
3556                          "Can't support bigalloc feature without "
3557                          "extents feature\n");
3558                 return 0;
3559         }
3560
3561 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3562         if (!readonly && (ext4_has_feature_quota(sb) ||
3563                           ext4_has_feature_project(sb))) {
3564                 ext4_msg(sb, KERN_ERR,
3565                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3566                 return 0;
3567         }
3568 #endif  /* CONFIG_QUOTA */
3569         return 1;
3570 }
3571
3572 /*
3573  * This function is called once a day if we have errors logged
3574  * on the file system
3575  */
3576 static void print_daily_error_info(struct timer_list *t)
3577 {
3578         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3579         struct super_block *sb = sbi->s_sb;
3580         struct ext4_super_block *es = sbi->s_es;
3581
3582         if (es->s_error_count)
3583                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3584                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3585                          le32_to_cpu(es->s_error_count));
3586         if (es->s_first_error_time) {
3587                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3588                        sb->s_id,
3589                        ext4_get_tstamp(es, s_first_error_time),
3590                        (int) sizeof(es->s_first_error_func),
3591                        es->s_first_error_func,
3592                        le32_to_cpu(es->s_first_error_line));
3593                 if (es->s_first_error_ino)
3594                         printk(KERN_CONT ": inode %u",
3595                                le32_to_cpu(es->s_first_error_ino));
3596                 if (es->s_first_error_block)
3597                         printk(KERN_CONT ": block %llu", (unsigned long long)
3598                                le64_to_cpu(es->s_first_error_block));
3599                 printk(KERN_CONT "\n");
3600         }
3601         if (es->s_last_error_time) {
3602                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3603                        sb->s_id,
3604                        ext4_get_tstamp(es, s_last_error_time),
3605                        (int) sizeof(es->s_last_error_func),
3606                        es->s_last_error_func,
3607                        le32_to_cpu(es->s_last_error_line));
3608                 if (es->s_last_error_ino)
3609                         printk(KERN_CONT ": inode %u",
3610                                le32_to_cpu(es->s_last_error_ino));
3611                 if (es->s_last_error_block)
3612                         printk(KERN_CONT ": block %llu", (unsigned long long)
3613                                le64_to_cpu(es->s_last_error_block));
3614                 printk(KERN_CONT "\n");
3615         }
3616         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3617 }
3618
3619 /* Find next suitable group and run ext4_init_inode_table */
3620 static int ext4_run_li_request(struct ext4_li_request *elr)
3621 {
3622         struct ext4_group_desc *gdp = NULL;
3623         struct super_block *sb = elr->lr_super;
3624         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3625         ext4_group_t group = elr->lr_next_group;
3626         unsigned int prefetch_ios = 0;
3627         int ret = 0;
3628         u64 start_time;
3629
3630         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3631                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3632                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3633                 if (prefetch_ios)
3634                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3635                                               prefetch_ios);
3636                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3637                                             prefetch_ios);
3638                 if (group >= elr->lr_next_group) {
3639                         ret = 1;
3640                         if (elr->lr_first_not_zeroed != ngroups &&
3641                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3642                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3643                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3644                                 ret = 0;
3645                         }
3646                 }
3647                 return ret;
3648         }
3649
3650         for (; group < ngroups; group++) {
3651                 gdp = ext4_get_group_desc(sb, group, NULL);
3652                 if (!gdp) {
3653                         ret = 1;
3654                         break;
3655                 }
3656
3657                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3658                         break;
3659         }
3660
3661         if (group >= ngroups)
3662                 ret = 1;
3663
3664         if (!ret) {
3665                 start_time = ktime_get_real_ns();
3666                 ret = ext4_init_inode_table(sb, group,
3667                                             elr->lr_timeout ? 0 : 1);
3668                 trace_ext4_lazy_itable_init(sb, group);
3669                 if (elr->lr_timeout == 0) {
3670                         elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3671                                 EXT4_SB(elr->lr_super)->s_li_wait_mult);
3672                 }
3673                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3674                 elr->lr_next_group = group + 1;
3675         }
3676         return ret;
3677 }
3678
3679 /*
3680  * Remove lr_request from the list_request and free the
3681  * request structure. Should be called with li_list_mtx held
3682  */
3683 static void ext4_remove_li_request(struct ext4_li_request *elr)
3684 {
3685         if (!elr)
3686                 return;
3687
3688         list_del(&elr->lr_request);
3689         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3690         kfree(elr);
3691 }
3692
3693 static void ext4_unregister_li_request(struct super_block *sb)
3694 {
3695         mutex_lock(&ext4_li_mtx);
3696         if (!ext4_li_info) {
3697                 mutex_unlock(&ext4_li_mtx);
3698                 return;
3699         }
3700
3701         mutex_lock(&ext4_li_info->li_list_mtx);
3702         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3703         mutex_unlock(&ext4_li_info->li_list_mtx);
3704         mutex_unlock(&ext4_li_mtx);
3705 }
3706
3707 static struct task_struct *ext4_lazyinit_task;
3708
3709 /*
3710  * This is the function where ext4lazyinit thread lives. It walks
3711  * through the request list searching for next scheduled filesystem.
3712  * When such a fs is found, run the lazy initialization request
3713  * (ext4_rn_li_request) and keep track of the time spend in this
3714  * function. Based on that time we compute next schedule time of
3715  * the request. When walking through the list is complete, compute
3716  * next waking time and put itself into sleep.
3717  */
3718 static int ext4_lazyinit_thread(void *arg)
3719 {
3720         struct ext4_lazy_init *eli = arg;
3721         struct list_head *pos, *n;
3722         struct ext4_li_request *elr;
3723         unsigned long next_wakeup, cur;
3724
3725         BUG_ON(NULL == eli);
3726         set_freezable();
3727
3728 cont_thread:
3729         while (true) {
3730                 next_wakeup = MAX_JIFFY_OFFSET;
3731
3732                 mutex_lock(&eli->li_list_mtx);
3733                 if (list_empty(&eli->li_request_list)) {
3734                         mutex_unlock(&eli->li_list_mtx);
3735                         goto exit_thread;
3736                 }
3737                 list_for_each_safe(pos, n, &eli->li_request_list) {
3738                         int err = 0;
3739                         int progress = 0;
3740                         elr = list_entry(pos, struct ext4_li_request,
3741                                          lr_request);
3742
3743                         if (time_before(jiffies, elr->lr_next_sched)) {
3744                                 if (time_before(elr->lr_next_sched, next_wakeup))
3745                                         next_wakeup = elr->lr_next_sched;
3746                                 continue;
3747                         }
3748                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3749                                 if (sb_start_write_trylock(elr->lr_super)) {
3750                                         progress = 1;
3751                                         /*
3752                                          * We hold sb->s_umount, sb can not
3753                                          * be removed from the list, it is
3754                                          * now safe to drop li_list_mtx
3755                                          */
3756                                         mutex_unlock(&eli->li_list_mtx);
3757                                         err = ext4_run_li_request(elr);
3758                                         sb_end_write(elr->lr_super);
3759                                         mutex_lock(&eli->li_list_mtx);
3760                                         n = pos->next;
3761                                 }
3762                                 up_read((&elr->lr_super->s_umount));
3763                         }
3764                         /* error, remove the lazy_init job */
3765                         if (err) {
3766                                 ext4_remove_li_request(elr);
3767                                 continue;
3768                         }
3769                         if (!progress) {
3770                                 elr->lr_next_sched = jiffies +
3771                                         get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3772                         }
3773                         if (time_before(elr->lr_next_sched, next_wakeup))
3774                                 next_wakeup = elr->lr_next_sched;
3775                 }
3776                 mutex_unlock(&eli->li_list_mtx);
3777
3778                 try_to_freeze();
3779
3780                 cur = jiffies;
3781                 if ((time_after_eq(cur, next_wakeup)) ||
3782                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3783                         cond_resched();
3784                         continue;
3785                 }
3786
3787                 schedule_timeout_interruptible(next_wakeup - cur);
3788
3789                 if (kthread_should_stop()) {
3790                         ext4_clear_request_list();
3791                         goto exit_thread;
3792                 }
3793         }
3794
3795 exit_thread:
3796         /*
3797          * It looks like the request list is empty, but we need
3798          * to check it under the li_list_mtx lock, to prevent any
3799          * additions into it, and of course we should lock ext4_li_mtx
3800          * to atomically free the list and ext4_li_info, because at
3801          * this point another ext4 filesystem could be registering
3802          * new one.
3803          */
3804         mutex_lock(&ext4_li_mtx);
3805         mutex_lock(&eli->li_list_mtx);
3806         if (!list_empty(&eli->li_request_list)) {
3807                 mutex_unlock(&eli->li_list_mtx);
3808                 mutex_unlock(&ext4_li_mtx);
3809                 goto cont_thread;
3810         }
3811         mutex_unlock(&eli->li_list_mtx);
3812         kfree(ext4_li_info);
3813         ext4_li_info = NULL;
3814         mutex_unlock(&ext4_li_mtx);
3815
3816         return 0;
3817 }
3818
3819 static void ext4_clear_request_list(void)
3820 {
3821         struct list_head *pos, *n;
3822         struct ext4_li_request *elr;
3823
3824         mutex_lock(&ext4_li_info->li_list_mtx);
3825         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3826                 elr = list_entry(pos, struct ext4_li_request,
3827                                  lr_request);
3828                 ext4_remove_li_request(elr);
3829         }
3830         mutex_unlock(&ext4_li_info->li_list_mtx);
3831 }
3832
3833 static int ext4_run_lazyinit_thread(void)
3834 {
3835         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3836                                          ext4_li_info, "ext4lazyinit");
3837         if (IS_ERR(ext4_lazyinit_task)) {
3838                 int err = PTR_ERR(ext4_lazyinit_task);
3839                 ext4_clear_request_list();
3840                 kfree(ext4_li_info);
3841                 ext4_li_info = NULL;
3842                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3843                                  "initialization thread\n",
3844                                  err);
3845                 return err;
3846         }
3847         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3848         return 0;
3849 }
3850
3851 /*
3852  * Check whether it make sense to run itable init. thread or not.
3853  * If there is at least one uninitialized inode table, return
3854  * corresponding group number, else the loop goes through all
3855  * groups and return total number of groups.
3856  */
3857 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3858 {
3859         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3860         struct ext4_group_desc *gdp = NULL;
3861
3862         if (!ext4_has_group_desc_csum(sb))
3863                 return ngroups;
3864
3865         for (group = 0; group < ngroups; group++) {
3866                 gdp = ext4_get_group_desc(sb, group, NULL);
3867                 if (!gdp)
3868                         continue;
3869
3870                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3871                         break;
3872         }
3873
3874         return group;
3875 }
3876
3877 static int ext4_li_info_new(void)
3878 {
3879         struct ext4_lazy_init *eli = NULL;
3880
3881         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3882         if (!eli)
3883                 return -ENOMEM;
3884
3885         INIT_LIST_HEAD(&eli->li_request_list);
3886         mutex_init(&eli->li_list_mtx);
3887
3888         eli->li_state |= EXT4_LAZYINIT_QUIT;
3889
3890         ext4_li_info = eli;
3891
3892         return 0;
3893 }
3894
3895 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3896                                             ext4_group_t start)
3897 {
3898         struct ext4_li_request *elr;
3899
3900         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3901         if (!elr)
3902                 return NULL;
3903
3904         elr->lr_super = sb;
3905         elr->lr_first_not_zeroed = start;
3906         if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3907                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3908                 elr->lr_next_group = start;
3909         } else {
3910                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3911         }
3912
3913         /*
3914          * Randomize first schedule time of the request to
3915          * spread the inode table initialization requests
3916          * better.
3917          */
3918         elr->lr_next_sched = jiffies + get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3919         return elr;
3920 }
3921
3922 int ext4_register_li_request(struct super_block *sb,
3923                              ext4_group_t first_not_zeroed)
3924 {
3925         struct ext4_sb_info *sbi = EXT4_SB(sb);
3926         struct ext4_li_request *elr = NULL;
3927         ext4_group_t ngroups = sbi->s_groups_count;
3928         int ret = 0;
3929
3930         mutex_lock(&ext4_li_mtx);
3931         if (sbi->s_li_request != NULL) {
3932                 /*
3933                  * Reset timeout so it can be computed again, because
3934                  * s_li_wait_mult might have changed.
3935                  */
3936                 sbi->s_li_request->lr_timeout = 0;
3937                 goto out;
3938         }
3939
3940         if (sb_rdonly(sb) ||
3941             (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
3942              (first_not_zeroed == ngroups || !test_opt(sb, INIT_INODE_TABLE))))
3943                 goto out;
3944
3945         elr = ext4_li_request_new(sb, first_not_zeroed);
3946         if (!elr) {
3947                 ret = -ENOMEM;
3948                 goto out;
3949         }
3950
3951         if (NULL == ext4_li_info) {
3952                 ret = ext4_li_info_new();
3953                 if (ret)
3954                         goto out;
3955         }
3956
3957         mutex_lock(&ext4_li_info->li_list_mtx);
3958         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3959         mutex_unlock(&ext4_li_info->li_list_mtx);
3960
3961         sbi->s_li_request = elr;
3962         /*
3963          * set elr to NULL here since it has been inserted to
3964          * the request_list and the removal and free of it is
3965          * handled by ext4_clear_request_list from now on.
3966          */
3967         elr = NULL;
3968
3969         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3970                 ret = ext4_run_lazyinit_thread();
3971                 if (ret)
3972                         goto out;
3973         }
3974 out:
3975         mutex_unlock(&ext4_li_mtx);
3976         if (ret)
3977                 kfree(elr);
3978         return ret;
3979 }
3980
3981 /*
3982  * We do not need to lock anything since this is called on
3983  * module unload.
3984  */
3985 static void ext4_destroy_lazyinit_thread(void)
3986 {
3987         /*
3988          * If thread exited earlier
3989          * there's nothing to be done.
3990          */
3991         if (!ext4_li_info || !ext4_lazyinit_task)
3992                 return;
3993
3994         kthread_stop(ext4_lazyinit_task);
3995 }
3996
3997 static int set_journal_csum_feature_set(struct super_block *sb)
3998 {
3999         int ret = 1;
4000         int compat, incompat;
4001         struct ext4_sb_info *sbi = EXT4_SB(sb);
4002
4003         if (ext4_has_metadata_csum(sb)) {
4004                 /* journal checksum v3 */
4005                 compat = 0;
4006                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4007         } else {
4008                 /* journal checksum v1 */
4009                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4010                 incompat = 0;
4011         }
4012
4013         jbd2_journal_clear_features(sbi->s_journal,
4014                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4015                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4016                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
4017         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4018                 ret = jbd2_journal_set_features(sbi->s_journal,
4019                                 compat, 0,
4020                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4021                                 incompat);
4022         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4023                 ret = jbd2_journal_set_features(sbi->s_journal,
4024                                 compat, 0,
4025                                 incompat);
4026                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4027                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4028         } else {
4029                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4030                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4031         }
4032
4033         return ret;
4034 }
4035
4036 /*
4037  * Note: calculating the overhead so we can be compatible with
4038  * historical BSD practice is quite difficult in the face of
4039  * clusters/bigalloc.  This is because multiple metadata blocks from
4040  * different block group can end up in the same allocation cluster.
4041  * Calculating the exact overhead in the face of clustered allocation
4042  * requires either O(all block bitmaps) in memory or O(number of block
4043  * groups**2) in time.  We will still calculate the superblock for
4044  * older file systems --- and if we come across with a bigalloc file
4045  * system with zero in s_overhead_clusters the estimate will be close to
4046  * correct especially for very large cluster sizes --- but for newer
4047  * file systems, it's better to calculate this figure once at mkfs
4048  * time, and store it in the superblock.  If the superblock value is
4049  * present (even for non-bigalloc file systems), we will use it.
4050  */
4051 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4052                           char *buf)
4053 {
4054         struct ext4_sb_info     *sbi = EXT4_SB(sb);
4055         struct ext4_group_desc  *gdp;
4056         ext4_fsblk_t            first_block, last_block, b;
4057         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
4058         int                     s, j, count = 0;
4059         int                     has_super = ext4_bg_has_super(sb, grp);
4060
4061         if (!ext4_has_feature_bigalloc(sb))
4062                 return (has_super + ext4_bg_num_gdb(sb, grp) +
4063                         (has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
4064                         sbi->s_itb_per_group + 2);
4065
4066         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4067                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
4068         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4069         for (i = 0; i < ngroups; i++) {
4070                 gdp = ext4_get_group_desc(sb, i, NULL);
4071                 b = ext4_block_bitmap(sb, gdp);
4072                 if (b >= first_block && b <= last_block) {
4073                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4074                         count++;
4075                 }
4076                 b = ext4_inode_bitmap(sb, gdp);
4077                 if (b >= first_block && b <= last_block) {
4078                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4079                         count++;
4080                 }
4081                 b = ext4_inode_table(sb, gdp);
4082                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4083                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4084                                 int c = EXT4_B2C(sbi, b - first_block);
4085                                 ext4_set_bit(c, buf);
4086                                 count++;
4087                         }
4088                 if (i != grp)
4089                         continue;
4090                 s = 0;
4091                 if (ext4_bg_has_super(sb, grp)) {
4092                         ext4_set_bit(s++, buf);
4093                         count++;
4094                 }
4095                 j = ext4_bg_num_gdb(sb, grp);
4096                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4097                         ext4_error(sb, "Invalid number of block group "
4098                                    "descriptor blocks: %d", j);
4099                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4100                 }
4101                 count += j;
4102                 for (; j > 0; j--)
4103                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4104         }
4105         if (!count)
4106                 return 0;
4107         return EXT4_CLUSTERS_PER_GROUP(sb) -
4108                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4109 }
4110
4111 /*
4112  * Compute the overhead and stash it in sbi->s_overhead
4113  */
4114 int ext4_calculate_overhead(struct super_block *sb)
4115 {
4116         struct ext4_sb_info *sbi = EXT4_SB(sb);
4117         struct ext4_super_block *es = sbi->s_es;
4118         struct inode *j_inode;
4119         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4120         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4121         ext4_fsblk_t overhead = 0;
4122         char *buf = (char *) get_zeroed_page(GFP_NOFS);
4123
4124         if (!buf)
4125                 return -ENOMEM;
4126
4127         /*
4128          * Compute the overhead (FS structures).  This is constant
4129          * for a given filesystem unless the number of block groups
4130          * changes so we cache the previous value until it does.
4131          */
4132
4133         /*
4134          * All of the blocks before first_data_block are overhead
4135          */
4136         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4137
4138         /*
4139          * Add the overhead found in each block group
4140          */
4141         for (i = 0; i < ngroups; i++) {
4142                 int blks;
4143
4144                 blks = count_overhead(sb, i, buf);
4145                 overhead += blks;
4146                 if (blks)
4147                         memset(buf, 0, PAGE_SIZE);
4148                 cond_resched();
4149         }
4150
4151         /*
4152          * Add the internal journal blocks whether the journal has been
4153          * loaded or not
4154          */
4155         if (sbi->s_journal && !sbi->s_journal_bdev)
4156                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4157         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4158                 /* j_inum for internal journal is non-zero */
4159                 j_inode = ext4_get_journal_inode(sb, j_inum);
4160                 if (j_inode) {
4161                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4162                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
4163                         iput(j_inode);
4164                 } else {
4165                         ext4_msg(sb, KERN_ERR, "can't get journal size");
4166                 }
4167         }
4168         sbi->s_overhead = overhead;
4169         smp_wmb();
4170         free_page((unsigned long) buf);
4171         return 0;
4172 }
4173
4174 static void ext4_set_resv_clusters(struct super_block *sb)
4175 {
4176         ext4_fsblk_t resv_clusters;
4177         struct ext4_sb_info *sbi = EXT4_SB(sb);
4178
4179         /*
4180          * There's no need to reserve anything when we aren't using extents.
4181          * The space estimates are exact, there are no unwritten extents,
4182          * hole punching doesn't need new metadata... This is needed especially
4183          * to keep ext2/3 backward compatibility.
4184          */
4185         if (!ext4_has_feature_extents(sb))
4186                 return;
4187         /*
4188          * By default we reserve 2% or 4096 clusters, whichever is smaller.
4189          * This should cover the situations where we can not afford to run
4190          * out of space like for example punch hole, or converting
4191          * unwritten extents in delalloc path. In most cases such
4192          * allocation would require 1, or 2 blocks, higher numbers are
4193          * very rare.
4194          */
4195         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4196                          sbi->s_cluster_bits);
4197
4198         do_div(resv_clusters, 50);
4199         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4200
4201         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4202 }
4203
4204 static const char *ext4_quota_mode(struct super_block *sb)
4205 {
4206 #ifdef CONFIG_QUOTA
4207         if (!ext4_quota_capable(sb))
4208                 return "none";
4209
4210         if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4211                 return "journalled";
4212         else
4213                 return "writeback";
4214 #else
4215         return "disabled";
4216 #endif
4217 }
4218
4219 static void ext4_setup_csum_trigger(struct super_block *sb,
4220                                     enum ext4_journal_trigger_type type,
4221                                     void (*trigger)(
4222                                         struct jbd2_buffer_trigger_type *type,
4223                                         struct buffer_head *bh,
4224                                         void *mapped_data,
4225                                         size_t size))
4226 {
4227         struct ext4_sb_info *sbi = EXT4_SB(sb);
4228
4229         sbi->s_journal_triggers[type].sb = sb;
4230         sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4231 }
4232
4233 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4234 {
4235         if (!sbi)
4236                 return;
4237
4238         kfree(sbi->s_blockgroup_lock);
4239         fs_put_dax(sbi->s_daxdev, NULL);
4240         kfree(sbi);
4241 }
4242
4243 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4244 {
4245         struct ext4_sb_info *sbi;
4246
4247         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4248         if (!sbi)
4249                 return NULL;
4250
4251         sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
4252                                            NULL, NULL);
4253
4254         sbi->s_blockgroup_lock =
4255                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4256
4257         if (!sbi->s_blockgroup_lock)
4258                 goto err_out;
4259
4260         sb->s_fs_info = sbi;
4261         sbi->s_sb = sb;
4262         return sbi;
4263 err_out:
4264         fs_put_dax(sbi->s_daxdev, NULL);
4265         kfree(sbi);
4266         return NULL;
4267 }
4268
4269 static void ext4_set_def_opts(struct super_block *sb,
4270                               struct ext4_super_block *es)
4271 {
4272         unsigned long def_mount_opts;
4273
4274         /* Set defaults before we parse the mount options */
4275         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4276         set_opt(sb, INIT_INODE_TABLE);
4277         if (def_mount_opts & EXT4_DEFM_DEBUG)
4278                 set_opt(sb, DEBUG);
4279         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4280                 set_opt(sb, GRPID);
4281         if (def_mount_opts & EXT4_DEFM_UID16)
4282                 set_opt(sb, NO_UID32);
4283         /* xattr user namespace & acls are now defaulted on */
4284         set_opt(sb, XATTR_USER);
4285 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4286         set_opt(sb, POSIX_ACL);
4287 #endif
4288         if (ext4_has_feature_fast_commit(sb))
4289                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4290         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4291         if (ext4_has_metadata_csum(sb))
4292                 set_opt(sb, JOURNAL_CHECKSUM);
4293
4294         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4295                 set_opt(sb, JOURNAL_DATA);
4296         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4297                 set_opt(sb, ORDERED_DATA);
4298         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4299                 set_opt(sb, WRITEBACK_DATA);
4300
4301         if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_PANIC)
4302                 set_opt(sb, ERRORS_PANIC);
4303         else if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_CONTINUE)
4304                 set_opt(sb, ERRORS_CONT);
4305         else
4306                 set_opt(sb, ERRORS_RO);
4307         /* block_validity enabled by default; disable with noblock_validity */
4308         set_opt(sb, BLOCK_VALIDITY);
4309         if (def_mount_opts & EXT4_DEFM_DISCARD)
4310                 set_opt(sb, DISCARD);
4311
4312         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4313                 set_opt(sb, BARRIER);
4314
4315         /*
4316          * enable delayed allocation by default
4317          * Use -o nodelalloc to turn it off
4318          */
4319         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4320             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4321                 set_opt(sb, DELALLOC);
4322
4323         if (sb->s_blocksize == PAGE_SIZE)
4324                 set_opt(sb, DIOREAD_NOLOCK);
4325 }
4326
4327 static int ext4_handle_clustersize(struct super_block *sb)
4328 {
4329         struct ext4_sb_info *sbi = EXT4_SB(sb);
4330         struct ext4_super_block *es = sbi->s_es;
4331         int clustersize;
4332
4333         /* Handle clustersize */
4334         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4335         if (ext4_has_feature_bigalloc(sb)) {
4336                 if (clustersize < sb->s_blocksize) {
4337                         ext4_msg(sb, KERN_ERR,
4338                                  "cluster size (%d) smaller than "
4339                                  "block size (%lu)", clustersize, sb->s_blocksize);
4340                         return -EINVAL;
4341                 }
4342                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4343                         le32_to_cpu(es->s_log_block_size);
4344                 sbi->s_clusters_per_group =
4345                         le32_to_cpu(es->s_clusters_per_group);
4346                 if (sbi->s_clusters_per_group > sb->s_blocksize * 8) {
4347                         ext4_msg(sb, KERN_ERR,
4348                                  "#clusters per group too big: %lu",
4349                                  sbi->s_clusters_per_group);
4350                         return -EINVAL;
4351                 }
4352                 if (sbi->s_blocks_per_group !=
4353                     (sbi->s_clusters_per_group * (clustersize / sb->s_blocksize))) {
4354                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4355                                  "clusters per group (%lu) inconsistent",
4356                                  sbi->s_blocks_per_group,
4357                                  sbi->s_clusters_per_group);
4358                         return -EINVAL;
4359                 }
4360         } else {
4361                 if (clustersize != sb->s_blocksize) {
4362                         ext4_msg(sb, KERN_ERR,
4363                                  "fragment/cluster size (%d) != "
4364                                  "block size (%lu)", clustersize, sb->s_blocksize);
4365                         return -EINVAL;
4366                 }
4367                 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
4368                         ext4_msg(sb, KERN_ERR,
4369                                  "#blocks per group too big: %lu",
4370                                  sbi->s_blocks_per_group);
4371                         return -EINVAL;
4372                 }
4373                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4374                 sbi->s_cluster_bits = 0;
4375         }
4376         sbi->s_cluster_ratio = clustersize / sb->s_blocksize;
4377
4378         /* Do we have standard group size of clustersize * 8 blocks ? */
4379         if (sbi->s_blocks_per_group == clustersize << 3)
4380                 set_opt2(sb, STD_GROUP_SIZE);
4381
4382         return 0;
4383 }
4384
4385 static void ext4_fast_commit_init(struct super_block *sb)
4386 {
4387         struct ext4_sb_info *sbi = EXT4_SB(sb);
4388
4389         /* Initialize fast commit stuff */
4390         atomic_set(&sbi->s_fc_subtid, 0);
4391         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4392         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4393         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4394         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4395         sbi->s_fc_bytes = 0;
4396         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4397         sbi->s_fc_ineligible_tid = 0;
4398         spin_lock_init(&sbi->s_fc_lock);
4399         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4400         sbi->s_fc_replay_state.fc_regions = NULL;
4401         sbi->s_fc_replay_state.fc_regions_size = 0;
4402         sbi->s_fc_replay_state.fc_regions_used = 0;
4403         sbi->s_fc_replay_state.fc_regions_valid = 0;
4404         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4405         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4406         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4407 }
4408
4409 static int ext4_inode_info_init(struct super_block *sb,
4410                                 struct ext4_super_block *es)
4411 {
4412         struct ext4_sb_info *sbi = EXT4_SB(sb);
4413
4414         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4415                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4416                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4417         } else {
4418                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4419                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4420                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4421                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4422                                  sbi->s_first_ino);
4423                         return -EINVAL;
4424                 }
4425                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4426                     (!is_power_of_2(sbi->s_inode_size)) ||
4427                     (sbi->s_inode_size > sb->s_blocksize)) {
4428                         ext4_msg(sb, KERN_ERR,
4429                                "unsupported inode size: %d",
4430                                sbi->s_inode_size);
4431                         ext4_msg(sb, KERN_ERR, "blocksize: %lu", sb->s_blocksize);
4432                         return -EINVAL;
4433                 }
4434                 /*
4435                  * i_atime_extra is the last extra field available for
4436                  * [acm]times in struct ext4_inode. Checking for that
4437                  * field should suffice to ensure we have extra space
4438                  * for all three.
4439                  */
4440                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4441                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4442                         sb->s_time_gran = 1;
4443                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4444                 } else {
4445                         sb->s_time_gran = NSEC_PER_SEC;
4446                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4447                 }
4448                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4449         }
4450
4451         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4452                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4453                         EXT4_GOOD_OLD_INODE_SIZE;
4454                 if (ext4_has_feature_extra_isize(sb)) {
4455                         unsigned v, max = (sbi->s_inode_size -
4456                                            EXT4_GOOD_OLD_INODE_SIZE);
4457
4458                         v = le16_to_cpu(es->s_want_extra_isize);
4459                         if (v > max) {
4460                                 ext4_msg(sb, KERN_ERR,
4461                                          "bad s_want_extra_isize: %d", v);
4462                                 return -EINVAL;
4463                         }
4464                         if (sbi->s_want_extra_isize < v)
4465                                 sbi->s_want_extra_isize = v;
4466
4467                         v = le16_to_cpu(es->s_min_extra_isize);
4468                         if (v > max) {
4469                                 ext4_msg(sb, KERN_ERR,
4470                                          "bad s_min_extra_isize: %d", v);
4471                                 return -EINVAL;
4472                         }
4473                         if (sbi->s_want_extra_isize < v)
4474                                 sbi->s_want_extra_isize = v;
4475                 }
4476         }
4477
4478         return 0;
4479 }
4480
4481 #if IS_ENABLED(CONFIG_UNICODE)
4482 static int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4483 {
4484         const struct ext4_sb_encodings *encoding_info;
4485         struct unicode_map *encoding;
4486         __u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4487
4488         if (!ext4_has_feature_casefold(sb) || sb->s_encoding)
4489                 return 0;
4490
4491         encoding_info = ext4_sb_read_encoding(es);
4492         if (!encoding_info) {
4493                 ext4_msg(sb, KERN_ERR,
4494                         "Encoding requested by superblock is unknown");
4495                 return -EINVAL;
4496         }
4497
4498         encoding = utf8_load(encoding_info->version);
4499         if (IS_ERR(encoding)) {
4500                 ext4_msg(sb, KERN_ERR,
4501                         "can't mount with superblock charset: %s-%u.%u.%u "
4502                         "not supported by the kernel. flags: 0x%x.",
4503                         encoding_info->name,
4504                         unicode_major(encoding_info->version),
4505                         unicode_minor(encoding_info->version),
4506                         unicode_rev(encoding_info->version),
4507                         encoding_flags);
4508                 return -EINVAL;
4509         }
4510         ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4511                 "%s-%u.%u.%u with flags 0x%hx", encoding_info->name,
4512                 unicode_major(encoding_info->version),
4513                 unicode_minor(encoding_info->version),
4514                 unicode_rev(encoding_info->version),
4515                 encoding_flags);
4516
4517         sb->s_encoding = encoding;
4518         sb->s_encoding_flags = encoding_flags;
4519
4520         return 0;
4521 }
4522 #else
4523 static inline int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4524 {
4525         return 0;
4526 }
4527 #endif
4528
4529 static int ext4_init_metadata_csum(struct super_block *sb, struct ext4_super_block *es)
4530 {
4531         struct ext4_sb_info *sbi = EXT4_SB(sb);
4532
4533         /* Warn if metadata_csum and gdt_csum are both set. */
4534         if (ext4_has_feature_metadata_csum(sb) &&
4535             ext4_has_feature_gdt_csum(sb))
4536                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4537                              "redundant flags; please run fsck.");
4538
4539         /* Check for a known checksum algorithm */
4540         if (!ext4_verify_csum_type(sb, es)) {
4541                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4542                          "unknown checksum algorithm.");
4543                 return -EINVAL;
4544         }
4545         ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4546                                 ext4_orphan_file_block_trigger);
4547
4548         /* Load the checksum driver */
4549         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4550         if (IS_ERR(sbi->s_chksum_driver)) {
4551                 int ret = PTR_ERR(sbi->s_chksum_driver);
4552                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4553                 sbi->s_chksum_driver = NULL;
4554                 return ret;
4555         }
4556
4557         /* Check superblock checksum */
4558         if (!ext4_superblock_csum_verify(sb, es)) {
4559                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4560                          "invalid superblock checksum.  Run e2fsck?");
4561                 return -EFSBADCRC;
4562         }
4563
4564         /* Precompute checksum seed for all metadata */
4565         if (ext4_has_feature_csum_seed(sb))
4566                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4567         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4568                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4569                                                sizeof(es->s_uuid));
4570         return 0;
4571 }
4572
4573 static int ext4_check_feature_compatibility(struct super_block *sb,
4574                                             struct ext4_super_block *es,
4575                                             int silent)
4576 {
4577         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4578             (ext4_has_compat_features(sb) ||
4579              ext4_has_ro_compat_features(sb) ||
4580              ext4_has_incompat_features(sb)))
4581                 ext4_msg(sb, KERN_WARNING,
4582                        "feature flags set on rev 0 fs, "
4583                        "running e2fsck is recommended");
4584
4585         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4586                 set_opt2(sb, HURD_COMPAT);
4587                 if (ext4_has_feature_64bit(sb)) {
4588                         ext4_msg(sb, KERN_ERR,
4589                                  "The Hurd can't support 64-bit file systems");
4590                         return -EINVAL;
4591                 }
4592
4593                 /*
4594                  * ea_inode feature uses l_i_version field which is not
4595                  * available in HURD_COMPAT mode.
4596                  */
4597                 if (ext4_has_feature_ea_inode(sb)) {
4598                         ext4_msg(sb, KERN_ERR,
4599                                  "ea_inode feature is not supported for Hurd");
4600                         return -EINVAL;
4601                 }
4602         }
4603
4604         if (IS_EXT2_SB(sb)) {
4605                 if (ext2_feature_set_ok(sb))
4606                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4607                                  "using the ext4 subsystem");
4608                 else {
4609                         /*
4610                          * If we're probing be silent, if this looks like
4611                          * it's actually an ext[34] filesystem.
4612                          */
4613                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4614                                 return -EINVAL;
4615                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4616                                  "to feature incompatibilities");
4617                         return -EINVAL;
4618                 }
4619         }
4620
4621         if (IS_EXT3_SB(sb)) {
4622                 if (ext3_feature_set_ok(sb))
4623                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4624                                  "using the ext4 subsystem");
4625                 else {
4626                         /*
4627                          * If we're probing be silent, if this looks like
4628                          * it's actually an ext4 filesystem.
4629                          */
4630                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4631                                 return -EINVAL;
4632                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4633                                  "to feature incompatibilities");
4634                         return -EINVAL;
4635                 }
4636         }
4637
4638         /*
4639          * Check feature flags regardless of the revision level, since we
4640          * previously didn't change the revision level when setting the flags,
4641          * so there is a chance incompat flags are set on a rev 0 filesystem.
4642          */
4643         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4644                 return -EINVAL;
4645
4646         return 0;
4647 }
4648
4649 static int ext4_geometry_check(struct super_block *sb,
4650                                struct ext4_super_block *es)
4651 {
4652         struct ext4_sb_info *sbi = EXT4_SB(sb);
4653         __u64 blocks_count;
4654
4655         /* check blocks count against device size */
4656         blocks_count = sb_bdev_nr_blocks(sb);
4657         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4658                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4659                        "exceeds size of device (%llu blocks)",
4660                        ext4_blocks_count(es), blocks_count);
4661                 return -EINVAL;
4662         }
4663
4664         /*
4665          * It makes no sense for the first data block to be beyond the end
4666          * of the filesystem.
4667          */
4668         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4669                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4670                          "block %u is beyond end of filesystem (%llu)",
4671                          le32_to_cpu(es->s_first_data_block),
4672                          ext4_blocks_count(es));
4673                 return -EINVAL;
4674         }
4675         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4676             (sbi->s_cluster_ratio == 1)) {
4677                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4678                          "block is 0 with a 1k block and cluster size");
4679                 return -EINVAL;
4680         }
4681
4682         blocks_count = (ext4_blocks_count(es) -
4683                         le32_to_cpu(es->s_first_data_block) +
4684                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4685         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4686         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4687                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4688                        "(block count %llu, first data block %u, "
4689                        "blocks per group %lu)", blocks_count,
4690                        ext4_blocks_count(es),
4691                        le32_to_cpu(es->s_first_data_block),
4692                        EXT4_BLOCKS_PER_GROUP(sb));
4693                 return -EINVAL;
4694         }
4695         sbi->s_groups_count = blocks_count;
4696         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4697                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4698         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4699             le32_to_cpu(es->s_inodes_count)) {
4700                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4701                          le32_to_cpu(es->s_inodes_count),
4702                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4703                 return -EINVAL;
4704         }
4705
4706         return 0;
4707 }
4708
4709 static void ext4_group_desc_free(struct ext4_sb_info *sbi)
4710 {
4711         struct buffer_head **group_desc;
4712         int i;
4713
4714         rcu_read_lock();
4715         group_desc = rcu_dereference(sbi->s_group_desc);
4716         for (i = 0; i < sbi->s_gdb_count; i++)
4717                 brelse(group_desc[i]);
4718         kvfree(group_desc);
4719         rcu_read_unlock();
4720 }
4721
4722 static int ext4_group_desc_init(struct super_block *sb,
4723                                 struct ext4_super_block *es,
4724                                 ext4_fsblk_t logical_sb_block,
4725                                 ext4_group_t *first_not_zeroed)
4726 {
4727         struct ext4_sb_info *sbi = EXT4_SB(sb);
4728         unsigned int db_count;
4729         ext4_fsblk_t block;
4730         int ret;
4731         int i;
4732
4733         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4734                    EXT4_DESC_PER_BLOCK(sb);
4735         if (ext4_has_feature_meta_bg(sb)) {
4736                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4737                         ext4_msg(sb, KERN_WARNING,
4738                                  "first meta block group too large: %u "
4739                                  "(group descriptor block count %u)",
4740                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4741                         return -EINVAL;
4742                 }
4743         }
4744         rcu_assign_pointer(sbi->s_group_desc,
4745                            kvmalloc_array(db_count,
4746                                           sizeof(struct buffer_head *),
4747                                           GFP_KERNEL));
4748         if (sbi->s_group_desc == NULL) {
4749                 ext4_msg(sb, KERN_ERR, "not enough memory");
4750                 return -ENOMEM;
4751         }
4752
4753         bgl_lock_init(sbi->s_blockgroup_lock);
4754
4755         /* Pre-read the descriptors into the buffer cache */
4756         for (i = 0; i < db_count; i++) {
4757                 block = descriptor_loc(sb, logical_sb_block, i);
4758                 ext4_sb_breadahead_unmovable(sb, block);
4759         }
4760
4761         for (i = 0; i < db_count; i++) {
4762                 struct buffer_head *bh;
4763
4764                 block = descriptor_loc(sb, logical_sb_block, i);
4765                 bh = ext4_sb_bread_unmovable(sb, block);
4766                 if (IS_ERR(bh)) {
4767                         ext4_msg(sb, KERN_ERR,
4768                                "can't read group descriptor %d", i);
4769                         sbi->s_gdb_count = i;
4770                         ret = PTR_ERR(bh);
4771                         goto out;
4772                 }
4773                 rcu_read_lock();
4774                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4775                 rcu_read_unlock();
4776         }
4777         sbi->s_gdb_count = db_count;
4778         if (!ext4_check_descriptors(sb, logical_sb_block, first_not_zeroed)) {
4779                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4780                 ret = -EFSCORRUPTED;
4781                 goto out;
4782         }
4783         return 0;
4784 out:
4785         ext4_group_desc_free(sbi);
4786         return ret;
4787 }
4788
4789 static int ext4_load_and_init_journal(struct super_block *sb,
4790                                       struct ext4_super_block *es,
4791                                       struct ext4_fs_context *ctx)
4792 {
4793         struct ext4_sb_info *sbi = EXT4_SB(sb);
4794         int err;
4795
4796         err = ext4_load_journal(sb, es, ctx->journal_devnum);
4797         if (err)
4798                 return err;
4799
4800         if (ext4_has_feature_64bit(sb) &&
4801             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4802                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4803                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4804                 goto out;
4805         }
4806
4807         if (!set_journal_csum_feature_set(sb)) {
4808                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4809                          "feature set");
4810                 goto out;
4811         }
4812
4813         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4814                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4815                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4816                 ext4_msg(sb, KERN_ERR,
4817                         "Failed to set fast commit journal feature");
4818                 goto out;
4819         }
4820
4821         /* We have now updated the journal if required, so we can
4822          * validate the data journaling mode. */
4823         switch (test_opt(sb, DATA_FLAGS)) {
4824         case 0:
4825                 /* No mode set, assume a default based on the journal
4826                  * capabilities: ORDERED_DATA if the journal can
4827                  * cope, else JOURNAL_DATA
4828                  */
4829                 if (jbd2_journal_check_available_features
4830                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4831                         set_opt(sb, ORDERED_DATA);
4832                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4833                 } else {
4834                         set_opt(sb, JOURNAL_DATA);
4835                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4836                 }
4837                 break;
4838
4839         case EXT4_MOUNT_ORDERED_DATA:
4840         case EXT4_MOUNT_WRITEBACK_DATA:
4841                 if (!jbd2_journal_check_available_features
4842                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4843                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4844                                "requested data journaling mode");
4845                         goto out;
4846                 }
4847                 break;
4848         default:
4849                 break;
4850         }
4851
4852         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4853             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4854                 ext4_msg(sb, KERN_ERR, "can't mount with "
4855                         "journal_async_commit in data=ordered mode");
4856                 goto out;
4857         }
4858
4859         set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
4860
4861         sbi->s_journal->j_submit_inode_data_buffers =
4862                 ext4_journal_submit_inode_data_buffers;
4863         sbi->s_journal->j_finish_inode_data_buffers =
4864                 ext4_journal_finish_inode_data_buffers;
4865
4866         return 0;
4867
4868 out:
4869         /* flush s_error_work before journal destroy. */
4870         flush_work(&sbi->s_error_work);
4871         jbd2_journal_destroy(sbi->s_journal);
4872         sbi->s_journal = NULL;
4873         return -EINVAL;
4874 }
4875
4876 static int ext4_journal_data_mode_check(struct super_block *sb)
4877 {
4878         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4879                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with "
4880                             "data=journal disables delayed allocation, "
4881                             "dioread_nolock, O_DIRECT and fast_commit support!\n");
4882                 /* can't mount with both data=journal and dioread_nolock. */
4883                 clear_opt(sb, DIOREAD_NOLOCK);
4884                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4885                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4886                         ext4_msg(sb, KERN_ERR, "can't mount with "
4887                                  "both data=journal and delalloc");
4888                         return -EINVAL;
4889                 }
4890                 if (test_opt(sb, DAX_ALWAYS)) {
4891                         ext4_msg(sb, KERN_ERR, "can't mount with "
4892                                  "both data=journal and dax");
4893                         return -EINVAL;
4894                 }
4895                 if (ext4_has_feature_encrypt(sb)) {
4896                         ext4_msg(sb, KERN_WARNING,
4897                                  "encrypted files will use data=ordered "
4898                                  "instead of data journaling mode");
4899                 }
4900                 if (test_opt(sb, DELALLOC))
4901                         clear_opt(sb, DELALLOC);
4902         } else {
4903                 sb->s_iflags |= SB_I_CGROUPWB;
4904         }
4905
4906         return 0;
4907 }
4908
4909 static int ext4_load_super(struct super_block *sb, ext4_fsblk_t *lsb,
4910                            int silent)
4911 {
4912         struct ext4_sb_info *sbi = EXT4_SB(sb);
4913         struct ext4_super_block *es;
4914         ext4_fsblk_t logical_sb_block;
4915         unsigned long offset = 0;
4916         struct buffer_head *bh;
4917         int ret = -EINVAL;
4918         int blocksize;
4919
4920         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4921         if (!blocksize) {
4922                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4923                 return -EINVAL;
4924         }
4925
4926         /*
4927          * The ext4 superblock will not be buffer aligned for other than 1kB
4928          * block sizes.  We need to calculate the offset from buffer start.
4929          */
4930         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4931                 logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
4932                 offset = do_div(logical_sb_block, blocksize);
4933         } else {
4934                 logical_sb_block = sbi->s_sb_block;
4935         }
4936
4937         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4938         if (IS_ERR(bh)) {
4939                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4940                 return PTR_ERR(bh);
4941         }
4942         /*
4943          * Note: s_es must be initialized as soon as possible because
4944          *       some ext4 macro-instructions depend on its value
4945          */
4946         es = (struct ext4_super_block *) (bh->b_data + offset);
4947         sbi->s_es = es;
4948         sb->s_magic = le16_to_cpu(es->s_magic);
4949         if (sb->s_magic != EXT4_SUPER_MAGIC) {
4950                 if (!silent)
4951                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4952                 goto out;
4953         }
4954
4955         if (le32_to_cpu(es->s_log_block_size) >
4956             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4957                 ext4_msg(sb, KERN_ERR,
4958                          "Invalid log block size: %u",
4959                          le32_to_cpu(es->s_log_block_size));
4960                 goto out;
4961         }
4962         if (le32_to_cpu(es->s_log_cluster_size) >
4963             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4964                 ext4_msg(sb, KERN_ERR,
4965                          "Invalid log cluster size: %u",
4966                          le32_to_cpu(es->s_log_cluster_size));
4967                 goto out;
4968         }
4969
4970         blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4971
4972         /*
4973          * If the default block size is not the same as the real block size,
4974          * we need to reload it.
4975          */
4976         if (sb->s_blocksize == blocksize) {
4977                 *lsb = logical_sb_block;
4978                 sbi->s_sbh = bh;
4979                 return 0;
4980         }
4981
4982         /*
4983          * bh must be released before kill_bdev(), otherwise
4984          * it won't be freed and its page also. kill_bdev()
4985          * is called by sb_set_blocksize().
4986          */
4987         brelse(bh);
4988         /* Validate the filesystem blocksize */
4989         if (!sb_set_blocksize(sb, blocksize)) {
4990                 ext4_msg(sb, KERN_ERR, "bad block size %d",
4991                                 blocksize);
4992                 bh = NULL;
4993                 goto out;
4994         }
4995
4996         logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
4997         offset = do_div(logical_sb_block, blocksize);
4998         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4999         if (IS_ERR(bh)) {
5000                 ext4_msg(sb, KERN_ERR, "Can't read superblock on 2nd try");
5001                 ret = PTR_ERR(bh);
5002                 bh = NULL;
5003                 goto out;
5004         }
5005         es = (struct ext4_super_block *)(bh->b_data + offset);
5006         sbi->s_es = es;
5007         if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
5008                 ext4_msg(sb, KERN_ERR, "Magic mismatch, very weird!");
5009                 goto out;
5010         }
5011         *lsb = logical_sb_block;
5012         sbi->s_sbh = bh;
5013         return 0;
5014 out:
5015         brelse(bh);
5016         return ret;
5017 }
5018
5019 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
5020 {
5021         struct ext4_super_block *es = NULL;
5022         struct ext4_sb_info *sbi = EXT4_SB(sb);
5023         struct flex_groups **flex_groups;
5024         ext4_fsblk_t block;
5025         ext4_fsblk_t logical_sb_block;
5026         struct inode *root;
5027         int ret = -ENOMEM;
5028         unsigned int i;
5029         int needs_recovery, has_huge_files;
5030         int err = 0;
5031         ext4_group_t first_not_zeroed;
5032         struct ext4_fs_context *ctx = fc->fs_private;
5033         int silent = fc->sb_flags & SB_SILENT;
5034
5035         /* Set defaults for the variables that will be set during parsing */
5036         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO))
5037                 ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5038
5039         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
5040         sbi->s_sectors_written_start =
5041                 part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
5042
5043         /* -EINVAL is default */
5044         ret = -EINVAL;
5045         err = ext4_load_super(sb, &logical_sb_block, silent);
5046         if (err)
5047                 goto out_fail;
5048
5049         es = sbi->s_es;
5050         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
5051
5052         err = ext4_init_metadata_csum(sb, es);
5053         if (err)
5054                 goto failed_mount;
5055
5056         ext4_set_def_opts(sb, es);
5057
5058         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
5059         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
5060         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
5061         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
5062         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
5063
5064         /*
5065          * set default s_li_wait_mult for lazyinit, for the case there is
5066          * no mount option specified.
5067          */
5068         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
5069
5070         if (ext4_inode_info_init(sb, es))
5071                 goto failed_mount;
5072
5073         err = parse_apply_sb_mount_options(sb, ctx);
5074         if (err < 0)
5075                 goto failed_mount;
5076
5077         sbi->s_def_mount_opt = sbi->s_mount_opt;
5078
5079         err = ext4_check_opt_consistency(fc, sb);
5080         if (err < 0)
5081                 goto failed_mount;
5082
5083         ext4_apply_options(fc, sb);
5084
5085         if (ext4_encoding_init(sb, es))
5086                 goto failed_mount;
5087
5088         if (ext4_journal_data_mode_check(sb))
5089                 goto failed_mount;
5090
5091         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5092                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5093
5094         /* i_version is always enabled now */
5095         sb->s_flags |= SB_I_VERSION;
5096
5097         if (ext4_check_feature_compatibility(sb, es, silent))
5098                 goto failed_mount;
5099
5100         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (sb->s_blocksize / 4)) {
5101                 ext4_msg(sb, KERN_ERR,
5102                          "Number of reserved GDT blocks insanely large: %d",
5103                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
5104                 goto failed_mount;
5105         }
5106
5107         if (sbi->s_daxdev) {
5108                 if (sb->s_blocksize == PAGE_SIZE)
5109                         set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
5110                 else
5111                         ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
5112         }
5113
5114         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
5115                 if (ext4_has_feature_inline_data(sb)) {
5116                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
5117                                         " that may contain inline data");
5118                         goto failed_mount;
5119                 }
5120                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
5121                         ext4_msg(sb, KERN_ERR,
5122                                 "DAX unsupported by block device.");
5123                         goto failed_mount;
5124                 }
5125         }
5126
5127         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
5128                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
5129                          es->s_encryption_level);
5130                 goto failed_mount;
5131         }
5132
5133         has_huge_files = ext4_has_feature_huge_file(sb);
5134         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
5135                                                       has_huge_files);
5136         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
5137
5138         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
5139         if (ext4_has_feature_64bit(sb)) {
5140                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
5141                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
5142                     !is_power_of_2(sbi->s_desc_size)) {
5143                         ext4_msg(sb, KERN_ERR,
5144                                "unsupported descriptor size %lu",
5145                                sbi->s_desc_size);
5146                         goto failed_mount;
5147                 }
5148         } else
5149                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
5150
5151         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
5152         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
5153
5154         sbi->s_inodes_per_block = sb->s_blocksize / EXT4_INODE_SIZE(sb);
5155         if (sbi->s_inodes_per_block == 0 || sbi->s_blocks_per_group == 0) {
5156                 if (!silent)
5157                         ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5158                 goto failed_mount;
5159         }
5160         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
5161             sbi->s_inodes_per_group > sb->s_blocksize * 8) {
5162                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
5163                          sbi->s_inodes_per_group);
5164                 goto failed_mount;
5165         }
5166         sbi->s_itb_per_group = sbi->s_inodes_per_group /
5167                                         sbi->s_inodes_per_block;
5168         sbi->s_desc_per_block = sb->s_blocksize / EXT4_DESC_SIZE(sb);
5169         sbi->s_mount_state = le16_to_cpu(es->s_state) & ~EXT4_FC_REPLAY;
5170         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
5171         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
5172
5173         for (i = 0; i < 4; i++)
5174                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
5175         sbi->s_def_hash_version = es->s_def_hash_version;
5176         if (ext4_has_feature_dir_index(sb)) {
5177                 i = le32_to_cpu(es->s_flags);
5178                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
5179                         sbi->s_hash_unsigned = 3;
5180                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
5181 #ifdef __CHAR_UNSIGNED__
5182                         if (!sb_rdonly(sb))
5183                                 es->s_flags |=
5184                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
5185                         sbi->s_hash_unsigned = 3;
5186 #else
5187                         if (!sb_rdonly(sb))
5188                                 es->s_flags |=
5189                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
5190 #endif
5191                 }
5192         }
5193
5194         if (ext4_handle_clustersize(sb))
5195                 goto failed_mount;
5196
5197         /*
5198          * Test whether we have more sectors than will fit in sector_t,
5199          * and whether the max offset is addressable by the page cache.
5200          */
5201         err = generic_check_addressable(sb->s_blocksize_bits,
5202                                         ext4_blocks_count(es));
5203         if (err) {
5204                 ext4_msg(sb, KERN_ERR, "filesystem"
5205                          " too large to mount safely on this system");
5206                 goto failed_mount;
5207         }
5208
5209         if (ext4_geometry_check(sb, es))
5210                 goto failed_mount;
5211
5212         err = ext4_group_desc_init(sb, es, logical_sb_block, &first_not_zeroed);
5213         if (err)
5214                 goto failed_mount;
5215
5216         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5217         spin_lock_init(&sbi->s_error_lock);
5218         INIT_WORK(&sbi->s_error_work, flush_stashed_error_work);
5219
5220         /* Register extent status tree shrinker */
5221         if (ext4_es_register_shrinker(sbi))
5222                 goto failed_mount3;
5223
5224         sbi->s_stripe = ext4_get_stripe_size(sbi);
5225         sbi->s_extent_max_zeroout_kb = 32;
5226
5227         /*
5228          * set up enough so that it can read an inode
5229          */
5230         sb->s_op = &ext4_sops;
5231         sb->s_export_op = &ext4_export_ops;
5232         sb->s_xattr = ext4_xattr_handlers;
5233 #ifdef CONFIG_FS_ENCRYPTION
5234         sb->s_cop = &ext4_cryptops;
5235 #endif
5236 #ifdef CONFIG_FS_VERITY
5237         sb->s_vop = &ext4_verityops;
5238 #endif
5239 #ifdef CONFIG_QUOTA
5240         sb->dq_op = &ext4_quota_operations;
5241         if (ext4_has_feature_quota(sb))
5242                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
5243         else
5244                 sb->s_qcop = &ext4_qctl_operations;
5245         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5246 #endif
5247         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
5248
5249         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5250         mutex_init(&sbi->s_orphan_lock);
5251
5252         ext4_fast_commit_init(sb);
5253
5254         sb->s_root = NULL;
5255
5256         needs_recovery = (es->s_last_orphan != 0 ||
5257                           ext4_has_feature_orphan_present(sb) ||
5258                           ext4_has_feature_journal_needs_recovery(sb));
5259
5260         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
5261                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
5262                         goto failed_mount3a;
5263
5264         /*
5265          * The first inode we look at is the journal inode.  Don't try
5266          * root first: it may be modified in the journal!
5267          */
5268         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5269                 err = ext4_load_and_init_journal(sb, es, ctx);
5270                 if (err)
5271                         goto failed_mount3a;
5272         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5273                    ext4_has_feature_journal_needs_recovery(sb)) {
5274                 ext4_msg(sb, KERN_ERR, "required journal recovery "
5275                        "suppressed and not mounted read-only");
5276                 goto failed_mount3a;
5277         } else {
5278                 /* Nojournal mode, all journal mount options are illegal */
5279                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5280                         ext4_msg(sb, KERN_ERR, "can't mount with "
5281                                  "journal_async_commit, fs mounted w/o journal");
5282                         goto failed_mount3a;
5283                 }
5284
5285                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
5286                         ext4_msg(sb, KERN_ERR, "can't mount with "
5287                                  "journal_checksum, fs mounted w/o journal");
5288                         goto failed_mount3a;
5289                 }
5290                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
5291                         ext4_msg(sb, KERN_ERR, "can't mount with "
5292                                  "commit=%lu, fs mounted w/o journal",
5293                                  sbi->s_commit_interval / HZ);
5294                         goto failed_mount3a;
5295                 }
5296                 if (EXT4_MOUNT_DATA_FLAGS &
5297                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
5298                         ext4_msg(sb, KERN_ERR, "can't mount with "
5299                                  "data=, fs mounted w/o journal");
5300                         goto failed_mount3a;
5301                 }
5302                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5303                 clear_opt(sb, JOURNAL_CHECKSUM);
5304                 clear_opt(sb, DATA_FLAGS);
5305                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
5306                 sbi->s_journal = NULL;
5307                 needs_recovery = 0;
5308         }
5309
5310         if (!test_opt(sb, NO_MBCACHE)) {
5311                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
5312                 if (!sbi->s_ea_block_cache) {
5313                         ext4_msg(sb, KERN_ERR,
5314                                  "Failed to create ea_block_cache");
5315                         goto failed_mount_wq;
5316                 }
5317
5318                 if (ext4_has_feature_ea_inode(sb)) {
5319                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5320                         if (!sbi->s_ea_inode_cache) {
5321                                 ext4_msg(sb, KERN_ERR,
5322                                          "Failed to create ea_inode_cache");
5323                                 goto failed_mount_wq;
5324                         }
5325                 }
5326         }
5327
5328         /*
5329          * Get the # of file system overhead blocks from the
5330          * superblock if present.
5331          */
5332         sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5333         /* ignore the precalculated value if it is ridiculous */
5334         if (sbi->s_overhead > ext4_blocks_count(es))
5335                 sbi->s_overhead = 0;
5336         /*
5337          * If the bigalloc feature is not enabled recalculating the
5338          * overhead doesn't take long, so we might as well just redo
5339          * it to make sure we are using the correct value.
5340          */
5341         if (!ext4_has_feature_bigalloc(sb))
5342                 sbi->s_overhead = 0;
5343         if (sbi->s_overhead == 0) {
5344                 err = ext4_calculate_overhead(sb);
5345                 if (err)
5346                         goto failed_mount_wq;
5347         }
5348
5349         /*
5350          * The maximum number of concurrent works can be high and
5351          * concurrency isn't really necessary.  Limit it to 1.
5352          */
5353         EXT4_SB(sb)->rsv_conversion_wq =
5354                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5355         if (!EXT4_SB(sb)->rsv_conversion_wq) {
5356                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5357                 ret = -ENOMEM;
5358                 goto failed_mount4;
5359         }
5360
5361         /*
5362          * The jbd2_journal_load will have done any necessary log recovery,
5363          * so we can safely mount the rest of the filesystem now.
5364          */
5365
5366         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5367         if (IS_ERR(root)) {
5368                 ext4_msg(sb, KERN_ERR, "get root inode failed");
5369                 ret = PTR_ERR(root);
5370                 root = NULL;
5371                 goto failed_mount4;
5372         }
5373         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5374                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5375                 iput(root);
5376                 goto failed_mount4;
5377         }
5378
5379         sb->s_root = d_make_root(root);
5380         if (!sb->s_root) {
5381                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
5382                 ret = -ENOMEM;
5383                 goto failed_mount4;
5384         }
5385
5386         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
5387         if (ret == -EROFS) {
5388                 sb->s_flags |= SB_RDONLY;
5389                 ret = 0;
5390         } else if (ret)
5391                 goto failed_mount4a;
5392
5393         ext4_set_resv_clusters(sb);
5394
5395         if (test_opt(sb, BLOCK_VALIDITY)) {
5396                 err = ext4_setup_system_zone(sb);
5397                 if (err) {
5398                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
5399                                  "zone (%d)", err);
5400                         goto failed_mount4a;
5401                 }
5402         }
5403         ext4_fc_replay_cleanup(sb);
5404
5405         ext4_ext_init(sb);
5406
5407         /*
5408          * Enable optimize_scan if number of groups is > threshold. This can be
5409          * turned off by passing "mb_optimize_scan=0". This can also be
5410          * turned on forcefully by passing "mb_optimize_scan=1".
5411          */
5412         if (!(ctx->spec & EXT4_SPEC_mb_optimize_scan)) {
5413                 if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5414                         set_opt2(sb, MB_OPTIMIZE_SCAN);
5415                 else
5416                         clear_opt2(sb, MB_OPTIMIZE_SCAN);
5417         }
5418
5419         err = ext4_mb_init(sb);
5420         if (err) {
5421                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5422                          err);
5423                 goto failed_mount5;
5424         }
5425
5426         /*
5427          * We can only set up the journal commit callback once
5428          * mballoc is initialized
5429          */
5430         if (sbi->s_journal)
5431                 sbi->s_journal->j_commit_callback =
5432                         ext4_journal_commit_callback;
5433
5434         block = ext4_count_free_clusters(sb);
5435         ext4_free_blocks_count_set(sbi->s_es,
5436                                    EXT4_C2B(sbi, block));
5437         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
5438                                   GFP_KERNEL);
5439         if (!err) {
5440                 unsigned long freei = ext4_count_free_inodes(sb);
5441                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
5442                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
5443                                           GFP_KERNEL);
5444         }
5445         if (!err)
5446                 err = percpu_counter_init(&sbi->s_dirs_counter,
5447                                           ext4_count_dirs(sb), GFP_KERNEL);
5448         if (!err)
5449                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5450                                           GFP_KERNEL);
5451         if (!err)
5452                 err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
5453                                           GFP_KERNEL);
5454         if (!err)
5455                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5456
5457         if (err) {
5458                 ext4_msg(sb, KERN_ERR, "insufficient memory");
5459                 goto failed_mount6;
5460         }
5461
5462         if (ext4_has_feature_flex_bg(sb))
5463                 if (!ext4_fill_flex_info(sb)) {
5464                         ext4_msg(sb, KERN_ERR,
5465                                "unable to initialize "
5466                                "flex_bg meta info!");
5467                         ret = -ENOMEM;
5468                         goto failed_mount6;
5469                 }
5470
5471         err = ext4_register_li_request(sb, first_not_zeroed);
5472         if (err)
5473                 goto failed_mount6;
5474
5475         err = ext4_register_sysfs(sb);
5476         if (err)
5477                 goto failed_mount7;
5478
5479         err = ext4_init_orphan_info(sb);
5480         if (err)
5481                 goto failed_mount8;
5482 #ifdef CONFIG_QUOTA
5483         /* Enable quota usage during mount. */
5484         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5485                 err = ext4_enable_quotas(sb);
5486                 if (err)
5487                         goto failed_mount9;
5488         }
5489 #endif  /* CONFIG_QUOTA */
5490
5491         /*
5492          * Save the original bdev mapping's wb_err value which could be
5493          * used to detect the metadata async write error.
5494          */
5495         spin_lock_init(&sbi->s_bdev_wb_lock);
5496         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5497                                  &sbi->s_bdev_wb_err);
5498         sb->s_bdev->bd_super = sb;
5499         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5500         ext4_orphan_cleanup(sb, es);
5501         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5502         /*
5503          * Update the checksum after updating free space/inode counters and
5504          * ext4_orphan_cleanup. Otherwise the superblock can have an incorrect
5505          * checksum in the buffer cache until it is written out and
5506          * e2fsprogs programs trying to open a file system immediately
5507          * after it is mounted can fail.
5508          */
5509         ext4_superblock_csum_set(sb);
5510         if (needs_recovery) {
5511                 ext4_msg(sb, KERN_INFO, "recovery complete");
5512                 err = ext4_mark_recovery_complete(sb, es);
5513                 if (err)
5514                         goto failed_mount9;
5515         }
5516
5517         if (test_opt(sb, DISCARD) && !bdev_max_discard_sectors(sb->s_bdev))
5518                 ext4_msg(sb, KERN_WARNING,
5519                          "mounting with \"discard\" option, but the device does not support discard");
5520
5521         if (es->s_error_count)
5522                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5523
5524         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5525         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5526         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5527         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5528         atomic_set(&sbi->s_warning_count, 0);
5529         atomic_set(&sbi->s_msg_count, 0);
5530
5531         return 0;
5532
5533 failed_mount9:
5534         ext4_release_orphan_info(sb);
5535 failed_mount8:
5536         ext4_unregister_sysfs(sb);
5537         kobject_put(&sbi->s_kobj);
5538 failed_mount7:
5539         ext4_unregister_li_request(sb);
5540 failed_mount6:
5541         ext4_mb_release(sb);
5542         rcu_read_lock();
5543         flex_groups = rcu_dereference(sbi->s_flex_groups);
5544         if (flex_groups) {
5545                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5546                         kvfree(flex_groups[i]);
5547                 kvfree(flex_groups);
5548         }
5549         rcu_read_unlock();
5550         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5551         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5552         percpu_counter_destroy(&sbi->s_dirs_counter);
5553         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5554         percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
5555         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5556 failed_mount5:
5557         ext4_ext_release(sb);
5558         ext4_release_system_zone(sb);
5559 failed_mount4a:
5560         dput(sb->s_root);
5561         sb->s_root = NULL;
5562 failed_mount4:
5563         ext4_msg(sb, KERN_ERR, "mount failed");
5564         if (EXT4_SB(sb)->rsv_conversion_wq)
5565                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5566 failed_mount_wq:
5567         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5568         sbi->s_ea_inode_cache = NULL;
5569
5570         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5571         sbi->s_ea_block_cache = NULL;
5572
5573         if (sbi->s_journal) {
5574                 /* flush s_error_work before journal destroy. */
5575                 flush_work(&sbi->s_error_work);
5576                 jbd2_journal_destroy(sbi->s_journal);
5577                 sbi->s_journal = NULL;
5578         }
5579 failed_mount3a:
5580         ext4_es_unregister_shrinker(sbi);
5581 failed_mount3:
5582         /* flush s_error_work before sbi destroy */
5583         flush_work(&sbi->s_error_work);
5584         del_timer_sync(&sbi->s_err_report);
5585         ext4_stop_mmpd(sbi);
5586         ext4_group_desc_free(sbi);
5587 failed_mount:
5588         if (sbi->s_chksum_driver)
5589                 crypto_free_shash(sbi->s_chksum_driver);
5590
5591 #if IS_ENABLED(CONFIG_UNICODE)
5592         utf8_unload(sb->s_encoding);
5593 #endif
5594
5595 #ifdef CONFIG_QUOTA
5596         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5597                 kfree(get_qf_name(sb, sbi, i));
5598 #endif
5599         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5600         /* ext4_blkdev_remove() calls kill_bdev(), release bh before it. */
5601         brelse(sbi->s_sbh);
5602         ext4_blkdev_remove(sbi);
5603 out_fail:
5604         sb->s_fs_info = NULL;
5605         return err ? err : ret;
5606 }
5607
5608 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5609 {
5610         struct ext4_fs_context *ctx = fc->fs_private;
5611         struct ext4_sb_info *sbi;
5612         const char *descr;
5613         int ret;
5614
5615         sbi = ext4_alloc_sbi(sb);
5616         if (!sbi)
5617                 return -ENOMEM;
5618
5619         fc->s_fs_info = sbi;
5620
5621         /* Cleanup superblock name */
5622         strreplace(sb->s_id, '/', '!');
5623
5624         sbi->s_sb_block = 1;    /* Default super block location */
5625         if (ctx->spec & EXT4_SPEC_s_sb_block)
5626                 sbi->s_sb_block = ctx->s_sb_block;
5627
5628         ret = __ext4_fill_super(fc, sb);
5629         if (ret < 0)
5630                 goto free_sbi;
5631
5632         if (sbi->s_journal) {
5633                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5634                         descr = " journalled data mode";
5635                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5636                         descr = " ordered data mode";
5637                 else
5638                         descr = " writeback data mode";
5639         } else
5640                 descr = "out journal";
5641
5642         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5643                 ext4_msg(sb, KERN_INFO, "mounted filesystem %pU with%s. "
5644                          "Quota mode: %s.", &sb->s_uuid, descr,
5645                          ext4_quota_mode(sb));
5646
5647         /* Update the s_overhead_clusters if necessary */
5648         ext4_update_overhead(sb, false);
5649         return 0;
5650
5651 free_sbi:
5652         ext4_free_sbi(sbi);
5653         fc->s_fs_info = NULL;
5654         return ret;
5655 }
5656
5657 static int ext4_get_tree(struct fs_context *fc)
5658 {
5659         return get_tree_bdev(fc, ext4_fill_super);
5660 }
5661
5662 /*
5663  * Setup any per-fs journal parameters now.  We'll do this both on
5664  * initial mount, once the journal has been initialised but before we've
5665  * done any recovery; and again on any subsequent remount.
5666  */
5667 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5668 {
5669         struct ext4_sb_info *sbi = EXT4_SB(sb);
5670
5671         journal->j_commit_interval = sbi->s_commit_interval;
5672         journal->j_min_batch_time = sbi->s_min_batch_time;
5673         journal->j_max_batch_time = sbi->s_max_batch_time;
5674         ext4_fc_init(sb, journal);
5675
5676         write_lock(&journal->j_state_lock);
5677         if (test_opt(sb, BARRIER))
5678                 journal->j_flags |= JBD2_BARRIER;
5679         else
5680                 journal->j_flags &= ~JBD2_BARRIER;
5681         if (test_opt(sb, DATA_ERR_ABORT))
5682                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5683         else
5684                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5685         write_unlock(&journal->j_state_lock);
5686 }
5687
5688 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5689                                              unsigned int journal_inum)
5690 {
5691         struct inode *journal_inode;
5692
5693         /*
5694          * Test for the existence of a valid inode on disk.  Bad things
5695          * happen if we iget() an unused inode, as the subsequent iput()
5696          * will try to delete it.
5697          */
5698         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5699         if (IS_ERR(journal_inode)) {
5700                 ext4_msg(sb, KERN_ERR, "no journal found");
5701                 return NULL;
5702         }
5703         if (!journal_inode->i_nlink) {
5704                 make_bad_inode(journal_inode);
5705                 iput(journal_inode);
5706                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5707                 return NULL;
5708         }
5709
5710         ext4_debug("Journal inode found at %p: %lld bytes\n",
5711                   journal_inode, journal_inode->i_size);
5712         if (!S_ISREG(journal_inode->i_mode) || IS_ENCRYPTED(journal_inode)) {
5713                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5714                 iput(journal_inode);
5715                 return NULL;
5716         }
5717         return journal_inode;
5718 }
5719
5720 static journal_t *ext4_get_journal(struct super_block *sb,
5721                                    unsigned int journal_inum)
5722 {
5723         struct inode *journal_inode;
5724         journal_t *journal;
5725
5726         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5727                 return NULL;
5728
5729         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5730         if (!journal_inode)
5731                 return NULL;
5732
5733         journal = jbd2_journal_init_inode(journal_inode);
5734         if (!journal) {
5735                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5736                 iput(journal_inode);
5737                 return NULL;
5738         }
5739         journal->j_private = sb;
5740         ext4_init_journal_params(sb, journal);
5741         return journal;
5742 }
5743
5744 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5745                                        dev_t j_dev)
5746 {
5747         struct buffer_head *bh;
5748         journal_t *journal;
5749         ext4_fsblk_t start;
5750         ext4_fsblk_t len;
5751         int hblock, blocksize;
5752         ext4_fsblk_t sb_block;
5753         unsigned long offset;
5754         struct ext4_super_block *es;
5755         struct block_device *bdev;
5756
5757         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5758                 return NULL;
5759
5760         bdev = ext4_blkdev_get(j_dev, sb);
5761         if (bdev == NULL)
5762                 return NULL;
5763
5764         blocksize = sb->s_blocksize;
5765         hblock = bdev_logical_block_size(bdev);
5766         if (blocksize < hblock) {
5767                 ext4_msg(sb, KERN_ERR,
5768                         "blocksize too small for journal device");
5769                 goto out_bdev;
5770         }
5771
5772         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5773         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5774         set_blocksize(bdev, blocksize);
5775         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5776                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5777                        "external journal");
5778                 goto out_bdev;
5779         }
5780
5781         es = (struct ext4_super_block *) (bh->b_data + offset);
5782         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5783             !(le32_to_cpu(es->s_feature_incompat) &
5784               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5785                 ext4_msg(sb, KERN_ERR, "external journal has "
5786                                         "bad superblock");
5787                 brelse(bh);
5788                 goto out_bdev;
5789         }
5790
5791         if ((le32_to_cpu(es->s_feature_ro_compat) &
5792              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5793             es->s_checksum != ext4_superblock_csum(sb, es)) {
5794                 ext4_msg(sb, KERN_ERR, "external journal has "
5795                                        "corrupt superblock");
5796                 brelse(bh);
5797                 goto out_bdev;
5798         }
5799
5800         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5801                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5802                 brelse(bh);
5803                 goto out_bdev;
5804         }
5805
5806         len = ext4_blocks_count(es);
5807         start = sb_block + 1;
5808         brelse(bh);     /* we're done with the superblock */
5809
5810         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5811                                         start, len, blocksize);
5812         if (!journal) {
5813                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5814                 goto out_bdev;
5815         }
5816         journal->j_private = sb;
5817         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5818                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5819                 goto out_journal;
5820         }
5821         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5822                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5823                                         "user (unsupported) - %d",
5824                         be32_to_cpu(journal->j_superblock->s_nr_users));
5825                 goto out_journal;
5826         }
5827         EXT4_SB(sb)->s_journal_bdev = bdev;
5828         ext4_init_journal_params(sb, journal);
5829         return journal;
5830
5831 out_journal:
5832         jbd2_journal_destroy(journal);
5833 out_bdev:
5834         ext4_blkdev_put(bdev);
5835         return NULL;
5836 }
5837
5838 static int ext4_load_journal(struct super_block *sb,
5839                              struct ext4_super_block *es,
5840                              unsigned long journal_devnum)
5841 {
5842         journal_t *journal;
5843         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5844         dev_t journal_dev;
5845         int err = 0;
5846         int really_read_only;
5847         int journal_dev_ro;
5848
5849         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5850                 return -EFSCORRUPTED;
5851
5852         if (journal_devnum &&
5853             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5854                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5855                         "numbers have changed");
5856                 journal_dev = new_decode_dev(journal_devnum);
5857         } else
5858                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5859
5860         if (journal_inum && journal_dev) {
5861                 ext4_msg(sb, KERN_ERR,
5862                          "filesystem has both journal inode and journal device!");
5863                 return -EINVAL;
5864         }
5865
5866         if (journal_inum) {
5867                 journal = ext4_get_journal(sb, journal_inum);
5868                 if (!journal)
5869                         return -EINVAL;
5870         } else {
5871                 journal = ext4_get_dev_journal(sb, journal_dev);
5872                 if (!journal)
5873                         return -EINVAL;
5874         }
5875
5876         journal_dev_ro = bdev_read_only(journal->j_dev);
5877         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5878
5879         if (journal_dev_ro && !sb_rdonly(sb)) {
5880                 ext4_msg(sb, KERN_ERR,
5881                          "journal device read-only, try mounting with '-o ro'");
5882                 err = -EROFS;
5883                 goto err_out;
5884         }
5885
5886         /*
5887          * Are we loading a blank journal or performing recovery after a
5888          * crash?  For recovery, we need to check in advance whether we
5889          * can get read-write access to the device.
5890          */
5891         if (ext4_has_feature_journal_needs_recovery(sb)) {
5892                 if (sb_rdonly(sb)) {
5893                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5894                                         "required on readonly filesystem");
5895                         if (really_read_only) {
5896                                 ext4_msg(sb, KERN_ERR, "write access "
5897                                         "unavailable, cannot proceed "
5898                                         "(try mounting with noload)");
5899                                 err = -EROFS;
5900                                 goto err_out;
5901                         }
5902                         ext4_msg(sb, KERN_INFO, "write access will "
5903                                "be enabled during recovery");
5904                 }
5905         }
5906
5907         if (!(journal->j_flags & JBD2_BARRIER))
5908                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5909
5910         if (!ext4_has_feature_journal_needs_recovery(sb))
5911                 err = jbd2_journal_wipe(journal, !really_read_only);
5912         if (!err) {
5913                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5914                 if (save)
5915                         memcpy(save, ((char *) es) +
5916                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5917                 err = jbd2_journal_load(journal);
5918                 if (save)
5919                         memcpy(((char *) es) + EXT4_S_ERR_START,
5920                                save, EXT4_S_ERR_LEN);
5921                 kfree(save);
5922         }
5923
5924         if (err) {
5925                 ext4_msg(sb, KERN_ERR, "error loading journal");
5926                 goto err_out;
5927         }
5928
5929         EXT4_SB(sb)->s_journal = journal;
5930         err = ext4_clear_journal_err(sb, es);
5931         if (err) {
5932                 EXT4_SB(sb)->s_journal = NULL;
5933                 jbd2_journal_destroy(journal);
5934                 return err;
5935         }
5936
5937         if (!really_read_only && journal_devnum &&
5938             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5939                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5940
5941                 /* Make sure we flush the recovery flag to disk. */
5942                 ext4_commit_super(sb);
5943         }
5944
5945         return 0;
5946
5947 err_out:
5948         jbd2_journal_destroy(journal);
5949         return err;
5950 }
5951
5952 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
5953 static void ext4_update_super(struct super_block *sb)
5954 {
5955         struct ext4_sb_info *sbi = EXT4_SB(sb);
5956         struct ext4_super_block *es = sbi->s_es;
5957         struct buffer_head *sbh = sbi->s_sbh;
5958
5959         lock_buffer(sbh);
5960         /*
5961          * If the file system is mounted read-only, don't update the
5962          * superblock write time.  This avoids updating the superblock
5963          * write time when we are mounting the root file system
5964          * read/only but we need to replay the journal; at that point,
5965          * for people who are east of GMT and who make their clock
5966          * tick in localtime for Windows bug-for-bug compatibility,
5967          * the clock is set in the future, and this will cause e2fsck
5968          * to complain and force a full file system check.
5969          */
5970         if (!(sb->s_flags & SB_RDONLY))
5971                 ext4_update_tstamp(es, s_wtime);
5972         es->s_kbytes_written =
5973                 cpu_to_le64(sbi->s_kbytes_written +
5974                     ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
5975                       sbi->s_sectors_written_start) >> 1));
5976         if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
5977                 ext4_free_blocks_count_set(es,
5978                         EXT4_C2B(sbi, percpu_counter_sum_positive(
5979                                 &sbi->s_freeclusters_counter)));
5980         if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
5981                 es->s_free_inodes_count =
5982                         cpu_to_le32(percpu_counter_sum_positive(
5983                                 &sbi->s_freeinodes_counter));
5984         /* Copy error information to the on-disk superblock */
5985         spin_lock(&sbi->s_error_lock);
5986         if (sbi->s_add_error_count > 0) {
5987                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5988                 if (!es->s_first_error_time && !es->s_first_error_time_hi) {
5989                         __ext4_update_tstamp(&es->s_first_error_time,
5990                                              &es->s_first_error_time_hi,
5991                                              sbi->s_first_error_time);
5992                         strncpy(es->s_first_error_func, sbi->s_first_error_func,
5993                                 sizeof(es->s_first_error_func));
5994                         es->s_first_error_line =
5995                                 cpu_to_le32(sbi->s_first_error_line);
5996                         es->s_first_error_ino =
5997                                 cpu_to_le32(sbi->s_first_error_ino);
5998                         es->s_first_error_block =
5999                                 cpu_to_le64(sbi->s_first_error_block);
6000                         es->s_first_error_errcode =
6001                                 ext4_errno_to_code(sbi->s_first_error_code);
6002                 }
6003                 __ext4_update_tstamp(&es->s_last_error_time,
6004                                      &es->s_last_error_time_hi,
6005                                      sbi->s_last_error_time);
6006                 strncpy(es->s_last_error_func, sbi->s_last_error_func,
6007                         sizeof(es->s_last_error_func));
6008                 es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
6009                 es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
6010                 es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
6011                 es->s_last_error_errcode =
6012                                 ext4_errno_to_code(sbi->s_last_error_code);
6013                 /*
6014                  * Start the daily error reporting function if it hasn't been
6015                  * started already
6016                  */
6017                 if (!es->s_error_count)
6018                         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
6019                 le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
6020                 sbi->s_add_error_count = 0;
6021         }
6022         spin_unlock(&sbi->s_error_lock);
6023
6024         ext4_superblock_csum_set(sb);
6025         unlock_buffer(sbh);
6026 }
6027
6028 static int ext4_commit_super(struct super_block *sb)
6029 {
6030         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
6031
6032         if (!sbh)
6033                 return -EINVAL;
6034         if (block_device_ejected(sb))
6035                 return -ENODEV;
6036
6037         ext4_update_super(sb);
6038
6039         lock_buffer(sbh);
6040         /* Buffer got discarded which means block device got invalidated */
6041         if (!buffer_mapped(sbh)) {
6042                 unlock_buffer(sbh);
6043                 return -EIO;
6044         }
6045
6046         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
6047                 /*
6048                  * Oh, dear.  A previous attempt to write the
6049                  * superblock failed.  This could happen because the
6050                  * USB device was yanked out.  Or it could happen to
6051                  * be a transient write error and maybe the block will
6052                  * be remapped.  Nothing we can do but to retry the
6053                  * write and hope for the best.
6054                  */
6055                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
6056                        "superblock detected");
6057                 clear_buffer_write_io_error(sbh);
6058                 set_buffer_uptodate(sbh);
6059         }
6060         get_bh(sbh);
6061         /* Clear potential dirty bit if it was journalled update */
6062         clear_buffer_dirty(sbh);
6063         sbh->b_end_io = end_buffer_write_sync;
6064         submit_bh(REQ_OP_WRITE | REQ_SYNC |
6065                   (test_opt(sb, BARRIER) ? REQ_FUA : 0), sbh);
6066         wait_on_buffer(sbh);
6067         if (buffer_write_io_error(sbh)) {
6068                 ext4_msg(sb, KERN_ERR, "I/O error while writing "
6069                        "superblock");
6070                 clear_buffer_write_io_error(sbh);
6071                 set_buffer_uptodate(sbh);
6072                 return -EIO;
6073         }
6074         return 0;
6075 }
6076
6077 /*
6078  * Have we just finished recovery?  If so, and if we are mounting (or
6079  * remounting) the filesystem readonly, then we will end up with a
6080  * consistent fs on disk.  Record that fact.
6081  */
6082 static int ext4_mark_recovery_complete(struct super_block *sb,
6083                                        struct ext4_super_block *es)
6084 {
6085         int err;
6086         journal_t *journal = EXT4_SB(sb)->s_journal;
6087
6088         if (!ext4_has_feature_journal(sb)) {
6089                 if (journal != NULL) {
6090                         ext4_error(sb, "Journal got removed while the fs was "
6091                                    "mounted!");
6092                         return -EFSCORRUPTED;
6093                 }
6094                 return 0;
6095         }
6096         jbd2_journal_lock_updates(journal);
6097         err = jbd2_journal_flush(journal, 0);
6098         if (err < 0)
6099                 goto out;
6100
6101         if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6102             ext4_has_feature_orphan_present(sb))) {
6103                 if (!ext4_orphan_file_empty(sb)) {
6104                         ext4_error(sb, "Orphan file not empty on read-only fs.");
6105                         err = -EFSCORRUPTED;
6106                         goto out;
6107                 }
6108                 ext4_clear_feature_journal_needs_recovery(sb);
6109                 ext4_clear_feature_orphan_present(sb);
6110                 ext4_commit_super(sb);
6111         }
6112 out:
6113         jbd2_journal_unlock_updates(journal);
6114         return err;
6115 }
6116
6117 /*
6118  * If we are mounting (or read-write remounting) a filesystem whose journal
6119  * has recorded an error from a previous lifetime, move that error to the
6120  * main filesystem now.
6121  */
6122 static int ext4_clear_journal_err(struct super_block *sb,
6123                                    struct ext4_super_block *es)
6124 {
6125         journal_t *journal;
6126         int j_errno;
6127         const char *errstr;
6128
6129         if (!ext4_has_feature_journal(sb)) {
6130                 ext4_error(sb, "Journal got removed while the fs was mounted!");
6131                 return -EFSCORRUPTED;
6132         }
6133
6134         journal = EXT4_SB(sb)->s_journal;
6135
6136         /*
6137          * Now check for any error status which may have been recorded in the
6138          * journal by a prior ext4_error() or ext4_abort()
6139          */
6140
6141         j_errno = jbd2_journal_errno(journal);
6142         if (j_errno) {
6143                 char nbuf[16];
6144
6145                 errstr = ext4_decode_error(sb, j_errno, nbuf);
6146                 ext4_warning(sb, "Filesystem error recorded "
6147                              "from previous mount: %s", errstr);
6148                 ext4_warning(sb, "Marking fs in need of filesystem check.");
6149
6150                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6151                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6152                 ext4_commit_super(sb);
6153
6154                 jbd2_journal_clear_err(journal);
6155                 jbd2_journal_update_sb_errno(journal);
6156         }
6157         return 0;
6158 }
6159
6160 /*
6161  * Force the running and committing transactions to commit,
6162  * and wait on the commit.
6163  */
6164 int ext4_force_commit(struct super_block *sb)
6165 {
6166         journal_t *journal;
6167
6168         if (sb_rdonly(sb))
6169                 return 0;
6170
6171         journal = EXT4_SB(sb)->s_journal;
6172         return ext4_journal_force_commit(journal);
6173 }
6174
6175 static int ext4_sync_fs(struct super_block *sb, int wait)
6176 {
6177         int ret = 0;
6178         tid_t target;
6179         bool needs_barrier = false;
6180         struct ext4_sb_info *sbi = EXT4_SB(sb);
6181
6182         if (unlikely(ext4_forced_shutdown(sbi)))
6183                 return 0;
6184
6185         trace_ext4_sync_fs(sb, wait);
6186         flush_workqueue(sbi->rsv_conversion_wq);
6187         /*
6188          * Writeback quota in non-journalled quota case - journalled quota has
6189          * no dirty dquots
6190          */
6191         dquot_writeback_dquots(sb, -1);
6192         /*
6193          * Data writeback is possible w/o journal transaction, so barrier must
6194          * being sent at the end of the function. But we can skip it if
6195          * transaction_commit will do it for us.
6196          */
6197         if (sbi->s_journal) {
6198                 target = jbd2_get_latest_transaction(sbi->s_journal);
6199                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6200                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6201                         needs_barrier = true;
6202
6203                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6204                         if (wait)
6205                                 ret = jbd2_log_wait_commit(sbi->s_journal,
6206                                                            target);
6207                 }
6208         } else if (wait && test_opt(sb, BARRIER))
6209                 needs_barrier = true;
6210         if (needs_barrier) {
6211                 int err;
6212                 err = blkdev_issue_flush(sb->s_bdev);
6213                 if (!ret)
6214                         ret = err;
6215         }
6216
6217         return ret;
6218 }
6219
6220 /*
6221  * LVM calls this function before a (read-only) snapshot is created.  This
6222  * gives us a chance to flush the journal completely and mark the fs clean.
6223  *
6224  * Note that only this function cannot bring a filesystem to be in a clean
6225  * state independently. It relies on upper layer to stop all data & metadata
6226  * modifications.
6227  */
6228 static int ext4_freeze(struct super_block *sb)
6229 {
6230         int error = 0;
6231         journal_t *journal;
6232
6233         if (sb_rdonly(sb))
6234                 return 0;
6235
6236         journal = EXT4_SB(sb)->s_journal;
6237
6238         if (journal) {
6239                 /* Now we set up the journal barrier. */
6240                 jbd2_journal_lock_updates(journal);
6241
6242                 /*
6243                  * Don't clear the needs_recovery flag if we failed to
6244                  * flush the journal.
6245                  */
6246                 error = jbd2_journal_flush(journal, 0);
6247                 if (error < 0)
6248                         goto out;
6249
6250                 /* Journal blocked and flushed, clear needs_recovery flag. */
6251                 ext4_clear_feature_journal_needs_recovery(sb);
6252                 if (ext4_orphan_file_empty(sb))
6253                         ext4_clear_feature_orphan_present(sb);
6254         }
6255
6256         error = ext4_commit_super(sb);
6257 out:
6258         if (journal)
6259                 /* we rely on upper layer to stop further updates */
6260                 jbd2_journal_unlock_updates(journal);
6261         return error;
6262 }
6263
6264 /*
6265  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6266  * flag here, even though the filesystem is not technically dirty yet.
6267  */
6268 static int ext4_unfreeze(struct super_block *sb)
6269 {
6270         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
6271                 return 0;
6272
6273         if (EXT4_SB(sb)->s_journal) {
6274                 /* Reset the needs_recovery flag before the fs is unlocked. */
6275                 ext4_set_feature_journal_needs_recovery(sb);
6276                 if (ext4_has_feature_orphan_file(sb))
6277                         ext4_set_feature_orphan_present(sb);
6278         }
6279
6280         ext4_commit_super(sb);
6281         return 0;
6282 }
6283
6284 /*
6285  * Structure to save mount options for ext4_remount's benefit
6286  */
6287 struct ext4_mount_options {
6288         unsigned long s_mount_opt;
6289         unsigned long s_mount_opt2;
6290         kuid_t s_resuid;
6291         kgid_t s_resgid;
6292         unsigned long s_commit_interval;
6293         u32 s_min_batch_time, s_max_batch_time;
6294 #ifdef CONFIG_QUOTA
6295         int s_jquota_fmt;
6296         char *s_qf_names[EXT4_MAXQUOTAS];
6297 #endif
6298 };
6299
6300 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6301 {
6302         struct ext4_fs_context *ctx = fc->fs_private;
6303         struct ext4_super_block *es;
6304         struct ext4_sb_info *sbi = EXT4_SB(sb);
6305         unsigned long old_sb_flags;
6306         struct ext4_mount_options old_opts;
6307         ext4_group_t g;
6308         int err = 0;
6309 #ifdef CONFIG_QUOTA
6310         int enable_quota = 0;
6311         int i, j;
6312         char *to_free[EXT4_MAXQUOTAS];
6313 #endif
6314
6315
6316         /* Store the original options */
6317         old_sb_flags = sb->s_flags;
6318         old_opts.s_mount_opt = sbi->s_mount_opt;
6319         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6320         old_opts.s_resuid = sbi->s_resuid;
6321         old_opts.s_resgid = sbi->s_resgid;
6322         old_opts.s_commit_interval = sbi->s_commit_interval;
6323         old_opts.s_min_batch_time = sbi->s_min_batch_time;
6324         old_opts.s_max_batch_time = sbi->s_max_batch_time;
6325 #ifdef CONFIG_QUOTA
6326         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6327         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6328                 if (sbi->s_qf_names[i]) {
6329                         char *qf_name = get_qf_name(sb, sbi, i);
6330
6331                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6332                         if (!old_opts.s_qf_names[i]) {
6333                                 for (j = 0; j < i; j++)
6334                                         kfree(old_opts.s_qf_names[j]);
6335                                 return -ENOMEM;
6336                         }
6337                 } else
6338                         old_opts.s_qf_names[i] = NULL;
6339 #endif
6340         if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)) {
6341                 if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6342                         ctx->journal_ioprio =
6343                                 sbi->s_journal->j_task->io_context->ioprio;
6344                 else
6345                         ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
6346
6347         }
6348
6349         ext4_apply_options(fc, sb);
6350
6351         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6352             test_opt(sb, JOURNAL_CHECKSUM)) {
6353                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6354                          "during remount not supported; ignoring");
6355                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6356         }
6357
6358         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6359                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6360                         ext4_msg(sb, KERN_ERR, "can't mount with "
6361                                  "both data=journal and delalloc");
6362                         err = -EINVAL;
6363                         goto restore_opts;
6364                 }
6365                 if (test_opt(sb, DIOREAD_NOLOCK)) {
6366                         ext4_msg(sb, KERN_ERR, "can't mount with "
6367                                  "both data=journal and dioread_nolock");
6368                         err = -EINVAL;
6369                         goto restore_opts;
6370                 }
6371         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6372                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6373                         ext4_msg(sb, KERN_ERR, "can't mount with "
6374                                 "journal_async_commit in data=ordered mode");
6375                         err = -EINVAL;
6376                         goto restore_opts;
6377                 }
6378         }
6379
6380         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6381                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6382                 err = -EINVAL;
6383                 goto restore_opts;
6384         }
6385
6386         if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
6387                 ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6388
6389         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6390                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6391
6392         es = sbi->s_es;
6393
6394         if (sbi->s_journal) {
6395                 ext4_init_journal_params(sb, sbi->s_journal);
6396                 set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6397         }
6398
6399         /* Flush outstanding errors before changing fs state */
6400         flush_work(&sbi->s_error_work);
6401
6402         if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6403                 if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
6404                         err = -EROFS;
6405                         goto restore_opts;
6406                 }
6407
6408                 if (fc->sb_flags & SB_RDONLY) {
6409                         err = sync_filesystem(sb);
6410                         if (err < 0)
6411                                 goto restore_opts;
6412                         err = dquot_suspend(sb, -1);
6413                         if (err < 0)
6414                                 goto restore_opts;
6415
6416                         /*
6417                          * First of all, the unconditional stuff we have to do
6418                          * to disable replay of the journal when we next remount
6419                          */
6420                         sb->s_flags |= SB_RDONLY;
6421
6422                         /*
6423                          * OK, test if we are remounting a valid rw partition
6424                          * readonly, and if so set the rdonly flag and then
6425                          * mark the partition as valid again.
6426                          */
6427                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6428                             (sbi->s_mount_state & EXT4_VALID_FS))
6429                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
6430
6431                         if (sbi->s_journal) {
6432                                 /*
6433                                  * We let remount-ro finish even if marking fs
6434                                  * as clean failed...
6435                                  */
6436                                 ext4_mark_recovery_complete(sb, es);
6437                         }
6438                 } else {
6439                         /* Make sure we can mount this feature set readwrite */
6440                         if (ext4_has_feature_readonly(sb) ||
6441                             !ext4_feature_set_ok(sb, 0)) {
6442                                 err = -EROFS;
6443                                 goto restore_opts;
6444                         }
6445                         /*
6446                          * Make sure the group descriptor checksums
6447                          * are sane.  If they aren't, refuse to remount r/w.
6448                          */
6449                         for (g = 0; g < sbi->s_groups_count; g++) {
6450                                 struct ext4_group_desc *gdp =
6451                                         ext4_get_group_desc(sb, g, NULL);
6452
6453                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6454                                         ext4_msg(sb, KERN_ERR,
6455                "ext4_remount: Checksum for group %u failed (%u!=%u)",
6456                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6457                                                le16_to_cpu(gdp->bg_checksum));
6458                                         err = -EFSBADCRC;
6459                                         goto restore_opts;
6460                                 }
6461                         }
6462
6463                         /*
6464                          * If we have an unprocessed orphan list hanging
6465                          * around from a previously readonly bdev mount,
6466                          * require a full umount/remount for now.
6467                          */
6468                         if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6469                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
6470                                        "remount RDWR because of unprocessed "
6471                                        "orphan inode list.  Please "
6472                                        "umount/remount instead");
6473                                 err = -EINVAL;
6474                                 goto restore_opts;
6475                         }
6476
6477                         /*
6478                          * Mounting a RDONLY partition read-write, so reread
6479                          * and store the current valid flag.  (It may have
6480                          * been changed by e2fsck since we originally mounted
6481                          * the partition.)
6482                          */
6483                         if (sbi->s_journal) {
6484                                 err = ext4_clear_journal_err(sb, es);
6485                                 if (err)
6486                                         goto restore_opts;
6487                         }
6488                         sbi->s_mount_state = (le16_to_cpu(es->s_state) &
6489                                               ~EXT4_FC_REPLAY);
6490
6491                         err = ext4_setup_super(sb, es, 0);
6492                         if (err)
6493                                 goto restore_opts;
6494
6495                         sb->s_flags &= ~SB_RDONLY;
6496                         if (ext4_has_feature_mmp(sb))
6497                                 if (ext4_multi_mount_protect(sb,
6498                                                 le64_to_cpu(es->s_mmp_block))) {
6499                                         err = -EROFS;
6500                                         goto restore_opts;
6501                                 }
6502 #ifdef CONFIG_QUOTA
6503                         enable_quota = 1;
6504 #endif
6505                 }
6506         }
6507
6508         /*
6509          * Reinitialize lazy itable initialization thread based on
6510          * current settings
6511          */
6512         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6513                 ext4_unregister_li_request(sb);
6514         else {
6515                 ext4_group_t first_not_zeroed;
6516                 first_not_zeroed = ext4_has_uninit_itable(sb);
6517                 ext4_register_li_request(sb, first_not_zeroed);
6518         }
6519
6520         /*
6521          * Handle creation of system zone data early because it can fail.
6522          * Releasing of existing data is done when we are sure remount will
6523          * succeed.
6524          */
6525         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6526                 err = ext4_setup_system_zone(sb);
6527                 if (err)
6528                         goto restore_opts;
6529         }
6530
6531         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6532                 err = ext4_commit_super(sb);
6533                 if (err)
6534                         goto restore_opts;
6535         }
6536
6537 #ifdef CONFIG_QUOTA
6538         /* Release old quota file names */
6539         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6540                 kfree(old_opts.s_qf_names[i]);
6541         if (enable_quota) {
6542                 if (sb_any_quota_suspended(sb))
6543                         dquot_resume(sb, -1);
6544                 else if (ext4_has_feature_quota(sb)) {
6545                         err = ext4_enable_quotas(sb);
6546                         if (err)
6547                                 goto restore_opts;
6548                 }
6549         }
6550 #endif
6551         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6552                 ext4_release_system_zone(sb);
6553
6554         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6555                 ext4_stop_mmpd(sbi);
6556
6557         return 0;
6558
6559 restore_opts:
6560         sb->s_flags = old_sb_flags;
6561         sbi->s_mount_opt = old_opts.s_mount_opt;
6562         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6563         sbi->s_resuid = old_opts.s_resuid;
6564         sbi->s_resgid = old_opts.s_resgid;
6565         sbi->s_commit_interval = old_opts.s_commit_interval;
6566         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6567         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6568         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6569                 ext4_release_system_zone(sb);
6570 #ifdef CONFIG_QUOTA
6571         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6572         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6573                 to_free[i] = get_qf_name(sb, sbi, i);
6574                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6575         }
6576         synchronize_rcu();
6577         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6578                 kfree(to_free[i]);
6579 #endif
6580         if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6581                 ext4_stop_mmpd(sbi);
6582         return err;
6583 }
6584
6585 static int ext4_reconfigure(struct fs_context *fc)
6586 {
6587         struct super_block *sb = fc->root->d_sb;
6588         int ret;
6589
6590         fc->s_fs_info = EXT4_SB(sb);
6591
6592         ret = ext4_check_opt_consistency(fc, sb);
6593         if (ret < 0)
6594                 return ret;
6595
6596         ret = __ext4_remount(fc, sb);
6597         if (ret < 0)
6598                 return ret;
6599
6600         ext4_msg(sb, KERN_INFO, "re-mounted %pU. Quota mode: %s.",
6601                  &sb->s_uuid, ext4_quota_mode(sb));
6602
6603         return 0;
6604 }
6605
6606 #ifdef CONFIG_QUOTA
6607 static int ext4_statfs_project(struct super_block *sb,
6608                                kprojid_t projid, struct kstatfs *buf)
6609 {
6610         struct kqid qid;
6611         struct dquot *dquot;
6612         u64 limit;
6613         u64 curblock;
6614
6615         qid = make_kqid_projid(projid);
6616         dquot = dqget(sb, qid);
6617         if (IS_ERR(dquot))
6618                 return PTR_ERR(dquot);
6619         spin_lock(&dquot->dq_dqb_lock);
6620
6621         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6622                              dquot->dq_dqb.dqb_bhardlimit);
6623         limit >>= sb->s_blocksize_bits;
6624
6625         if (limit && buf->f_blocks > limit) {
6626                 curblock = (dquot->dq_dqb.dqb_curspace +
6627                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6628                 buf->f_blocks = limit;
6629                 buf->f_bfree = buf->f_bavail =
6630                         (buf->f_blocks > curblock) ?
6631                          (buf->f_blocks - curblock) : 0;
6632         }
6633
6634         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6635                              dquot->dq_dqb.dqb_ihardlimit);
6636         if (limit && buf->f_files > limit) {
6637                 buf->f_files = limit;
6638                 buf->f_ffree =
6639                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6640                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6641         }
6642
6643         spin_unlock(&dquot->dq_dqb_lock);
6644         dqput(dquot);
6645         return 0;
6646 }
6647 #endif
6648
6649 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6650 {
6651         struct super_block *sb = dentry->d_sb;
6652         struct ext4_sb_info *sbi = EXT4_SB(sb);
6653         struct ext4_super_block *es = sbi->s_es;
6654         ext4_fsblk_t overhead = 0, resv_blocks;
6655         s64 bfree;
6656         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6657
6658         if (!test_opt(sb, MINIX_DF))
6659                 overhead = sbi->s_overhead;
6660
6661         buf->f_type = EXT4_SUPER_MAGIC;
6662         buf->f_bsize = sb->s_blocksize;
6663         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6664         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6665                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6666         /* prevent underflow in case that few free space is available */
6667         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6668         buf->f_bavail = buf->f_bfree -
6669                         (ext4_r_blocks_count(es) + resv_blocks);
6670         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6671                 buf->f_bavail = 0;
6672         buf->f_files = le32_to_cpu(es->s_inodes_count);
6673         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6674         buf->f_namelen = EXT4_NAME_LEN;
6675         buf->f_fsid = uuid_to_fsid(es->s_uuid);
6676
6677 #ifdef CONFIG_QUOTA
6678         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6679             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6680                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6681 #endif
6682         return 0;
6683 }
6684
6685
6686 #ifdef CONFIG_QUOTA
6687
6688 /*
6689  * Helper functions so that transaction is started before we acquire dqio_sem
6690  * to keep correct lock ordering of transaction > dqio_sem
6691  */
6692 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6693 {
6694         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6695 }
6696
6697 static int ext4_write_dquot(struct dquot *dquot)
6698 {
6699         int ret, err;
6700         handle_t *handle;
6701         struct inode *inode;
6702
6703         inode = dquot_to_inode(dquot);
6704         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6705                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6706         if (IS_ERR(handle))
6707                 return PTR_ERR(handle);
6708         ret = dquot_commit(dquot);
6709         err = ext4_journal_stop(handle);
6710         if (!ret)
6711                 ret = err;
6712         return ret;
6713 }
6714
6715 static int ext4_acquire_dquot(struct dquot *dquot)
6716 {
6717         int ret, err;
6718         handle_t *handle;
6719
6720         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6721                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6722         if (IS_ERR(handle))
6723                 return PTR_ERR(handle);
6724         ret = dquot_acquire(dquot);
6725         err = ext4_journal_stop(handle);
6726         if (!ret)
6727                 ret = err;
6728         return ret;
6729 }
6730
6731 static int ext4_release_dquot(struct dquot *dquot)
6732 {
6733         int ret, err;
6734         handle_t *handle;
6735
6736         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6737                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6738         if (IS_ERR(handle)) {
6739                 /* Release dquot anyway to avoid endless cycle in dqput() */
6740                 dquot_release(dquot);
6741                 return PTR_ERR(handle);
6742         }
6743         ret = dquot_release(dquot);
6744         err = ext4_journal_stop(handle);
6745         if (!ret)
6746                 ret = err;
6747         return ret;
6748 }
6749
6750 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6751 {
6752         struct super_block *sb = dquot->dq_sb;
6753
6754         if (ext4_is_quota_journalled(sb)) {
6755                 dquot_mark_dquot_dirty(dquot);
6756                 return ext4_write_dquot(dquot);
6757         } else {
6758                 return dquot_mark_dquot_dirty(dquot);
6759         }
6760 }
6761
6762 static int ext4_write_info(struct super_block *sb, int type)
6763 {
6764         int ret, err;
6765         handle_t *handle;
6766
6767         /* Data block + inode block */
6768         handle = ext4_journal_start_sb(sb, EXT4_HT_QUOTA, 2);
6769         if (IS_ERR(handle))
6770                 return PTR_ERR(handle);
6771         ret = dquot_commit_info(sb, type);
6772         err = ext4_journal_stop(handle);
6773         if (!ret)
6774                 ret = err;
6775         return ret;
6776 }
6777
6778 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6779 {
6780         struct ext4_inode_info *ei = EXT4_I(inode);
6781
6782         /* The first argument of lockdep_set_subclass has to be
6783          * *exactly* the same as the argument to init_rwsem() --- in
6784          * this case, in init_once() --- or lockdep gets unhappy
6785          * because the name of the lock is set using the
6786          * stringification of the argument to init_rwsem().
6787          */
6788         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6789         lockdep_set_subclass(&ei->i_data_sem, subclass);
6790 }
6791
6792 /*
6793  * Standard function to be called on quota_on
6794  */
6795 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6796                          const struct path *path)
6797 {
6798         int err;
6799
6800         if (!test_opt(sb, QUOTA))
6801                 return -EINVAL;
6802
6803         /* Quotafile not on the same filesystem? */
6804         if (path->dentry->d_sb != sb)
6805                 return -EXDEV;
6806
6807         /* Quota already enabled for this file? */
6808         if (IS_NOQUOTA(d_inode(path->dentry)))
6809                 return -EBUSY;
6810
6811         /* Journaling quota? */
6812         if (EXT4_SB(sb)->s_qf_names[type]) {
6813                 /* Quotafile not in fs root? */
6814                 if (path->dentry->d_parent != sb->s_root)
6815                         ext4_msg(sb, KERN_WARNING,
6816                                 "Quota file not on filesystem root. "
6817                                 "Journaled quota will not work");
6818                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6819         } else {
6820                 /*
6821                  * Clear the flag just in case mount options changed since
6822                  * last time.
6823                  */
6824                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6825         }
6826
6827         /*
6828          * When we journal data on quota file, we have to flush journal to see
6829          * all updates to the file when we bypass pagecache...
6830          */
6831         if (EXT4_SB(sb)->s_journal &&
6832             ext4_should_journal_data(d_inode(path->dentry))) {
6833                 /*
6834                  * We don't need to lock updates but journal_flush() could
6835                  * otherwise be livelocked...
6836                  */
6837                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6838                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal, 0);
6839                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6840                 if (err)
6841                         return err;
6842         }
6843
6844         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6845         err = dquot_quota_on(sb, type, format_id, path);
6846         if (!err) {
6847                 struct inode *inode = d_inode(path->dentry);
6848                 handle_t *handle;
6849
6850                 /*
6851                  * Set inode flags to prevent userspace from messing with quota
6852                  * files. If this fails, we return success anyway since quotas
6853                  * are already enabled and this is not a hard failure.
6854                  */
6855                 inode_lock(inode);
6856                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6857                 if (IS_ERR(handle))
6858                         goto unlock_inode;
6859                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6860                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6861                                 S_NOATIME | S_IMMUTABLE);
6862                 err = ext4_mark_inode_dirty(handle, inode);
6863                 ext4_journal_stop(handle);
6864         unlock_inode:
6865                 inode_unlock(inode);
6866                 if (err)
6867                         dquot_quota_off(sb, type);
6868         }
6869         if (err)
6870                 lockdep_set_quota_inode(path->dentry->d_inode,
6871                                              I_DATA_SEM_NORMAL);
6872         return err;
6873 }
6874
6875 static inline bool ext4_check_quota_inum(int type, unsigned long qf_inum)
6876 {
6877         switch (type) {
6878         case USRQUOTA:
6879                 return qf_inum == EXT4_USR_QUOTA_INO;
6880         case GRPQUOTA:
6881                 return qf_inum == EXT4_GRP_QUOTA_INO;
6882         case PRJQUOTA:
6883                 return qf_inum >= EXT4_GOOD_OLD_FIRST_INO;
6884         default:
6885                 BUG();
6886         }
6887 }
6888
6889 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6890                              unsigned int flags)
6891 {
6892         int err;
6893         struct inode *qf_inode;
6894         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6895                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6896                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6897                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6898         };
6899
6900         BUG_ON(!ext4_has_feature_quota(sb));
6901
6902         if (!qf_inums[type])
6903                 return -EPERM;
6904
6905         if (!ext4_check_quota_inum(type, qf_inums[type])) {
6906                 ext4_error(sb, "Bad quota inum: %lu, type: %d",
6907                                 qf_inums[type], type);
6908                 return -EUCLEAN;
6909         }
6910
6911         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6912         if (IS_ERR(qf_inode)) {
6913                 ext4_error(sb, "Bad quota inode: %lu, type: %d",
6914                                 qf_inums[type], type);
6915                 return PTR_ERR(qf_inode);
6916         }
6917
6918         /* Don't account quota for quota files to avoid recursion */
6919         qf_inode->i_flags |= S_NOQUOTA;
6920         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6921         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6922         if (err)
6923                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6924         iput(qf_inode);
6925
6926         return err;
6927 }
6928
6929 /* Enable usage tracking for all quota types. */
6930 int ext4_enable_quotas(struct super_block *sb)
6931 {
6932         int type, err = 0;
6933         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6934                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6935                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6936                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6937         };
6938         bool quota_mopt[EXT4_MAXQUOTAS] = {
6939                 test_opt(sb, USRQUOTA),
6940                 test_opt(sb, GRPQUOTA),
6941                 test_opt(sb, PRJQUOTA),
6942         };
6943
6944         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6945         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6946                 if (qf_inums[type]) {
6947                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6948                                 DQUOT_USAGE_ENABLED |
6949                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6950                         if (err) {
6951                                 ext4_warning(sb,
6952                                         "Failed to enable quota tracking "
6953                                         "(type=%d, err=%d, ino=%lu). "
6954                                         "Please run e2fsck to fix.", type,
6955                                         err, qf_inums[type]);
6956                                 for (type--; type >= 0; type--) {
6957                                         struct inode *inode;
6958
6959                                         inode = sb_dqopt(sb)->files[type];
6960                                         if (inode)
6961                                                 inode = igrab(inode);
6962                                         dquot_quota_off(sb, type);
6963                                         if (inode) {
6964                                                 lockdep_set_quota_inode(inode,
6965                                                         I_DATA_SEM_NORMAL);
6966                                                 iput(inode);
6967                                         }
6968                                 }
6969
6970                                 return err;
6971                         }
6972                 }
6973         }
6974         return 0;
6975 }
6976
6977 static int ext4_quota_off(struct super_block *sb, int type)
6978 {
6979         struct inode *inode = sb_dqopt(sb)->files[type];
6980         handle_t *handle;
6981         int err;
6982
6983         /* Force all delayed allocation blocks to be allocated.
6984          * Caller already holds s_umount sem */
6985         if (test_opt(sb, DELALLOC))
6986                 sync_filesystem(sb);
6987
6988         if (!inode || !igrab(inode))
6989                 goto out;
6990
6991         err = dquot_quota_off(sb, type);
6992         if (err || ext4_has_feature_quota(sb))
6993                 goto out_put;
6994
6995         inode_lock(inode);
6996         /*
6997          * Update modification times of quota files when userspace can
6998          * start looking at them. If we fail, we return success anyway since
6999          * this is not a hard failure and quotas are already disabled.
7000          */
7001         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7002         if (IS_ERR(handle)) {
7003                 err = PTR_ERR(handle);
7004                 goto out_unlock;
7005         }
7006         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
7007         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
7008         inode->i_mtime = inode->i_ctime = current_time(inode);
7009         err = ext4_mark_inode_dirty(handle, inode);
7010         ext4_journal_stop(handle);
7011 out_unlock:
7012         inode_unlock(inode);
7013 out_put:
7014         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
7015         iput(inode);
7016         return err;
7017 out:
7018         return dquot_quota_off(sb, type);
7019 }
7020
7021 /* Read data from quotafile - avoid pagecache and such because we cannot afford
7022  * acquiring the locks... As quota files are never truncated and quota code
7023  * itself serializes the operations (and no one else should touch the files)
7024  * we don't have to be afraid of races */
7025 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
7026                                size_t len, loff_t off)
7027 {
7028         struct inode *inode = sb_dqopt(sb)->files[type];
7029         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7030         int offset = off & (sb->s_blocksize - 1);
7031         int tocopy;
7032         size_t toread;
7033         struct buffer_head *bh;
7034         loff_t i_size = i_size_read(inode);
7035
7036         if (off > i_size)
7037                 return 0;
7038         if (off+len > i_size)
7039                 len = i_size-off;
7040         toread = len;
7041         while (toread > 0) {
7042                 tocopy = min_t(unsigned long, sb->s_blocksize - offset, toread);
7043                 bh = ext4_bread(NULL, inode, blk, 0);
7044                 if (IS_ERR(bh))
7045                         return PTR_ERR(bh);
7046                 if (!bh)        /* A hole? */
7047                         memset(data, 0, tocopy);
7048                 else
7049                         memcpy(data, bh->b_data+offset, tocopy);
7050                 brelse(bh);
7051                 offset = 0;
7052                 toread -= tocopy;
7053                 data += tocopy;
7054                 blk++;
7055         }
7056         return len;
7057 }
7058
7059 /* Write to quotafile (we know the transaction is already started and has
7060  * enough credits) */
7061 static ssize_t ext4_quota_write(struct super_block *sb, int type,
7062                                 const char *data, size_t len, loff_t off)
7063 {
7064         struct inode *inode = sb_dqopt(sb)->files[type];
7065         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7066         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
7067         int retries = 0;
7068         struct buffer_head *bh;
7069         handle_t *handle = journal_current_handle();
7070
7071         if (!handle) {
7072                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7073                         " cancelled because transaction is not started",
7074                         (unsigned long long)off, (unsigned long long)len);
7075                 return -EIO;
7076         }
7077         /*
7078          * Since we account only one data block in transaction credits,
7079          * then it is impossible to cross a block boundary.
7080          */
7081         if (sb->s_blocksize - offset < len) {
7082                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7083                         " cancelled because not block aligned",
7084                         (unsigned long long)off, (unsigned long long)len);
7085                 return -EIO;
7086         }
7087
7088         do {
7089                 bh = ext4_bread(handle, inode, blk,
7090                                 EXT4_GET_BLOCKS_CREATE |
7091                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
7092         } while (PTR_ERR(bh) == -ENOSPC &&
7093                  ext4_should_retry_alloc(inode->i_sb, &retries));
7094         if (IS_ERR(bh))
7095                 return PTR_ERR(bh);
7096         if (!bh)
7097                 goto out;
7098         BUFFER_TRACE(bh, "get write access");
7099         err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
7100         if (err) {
7101                 brelse(bh);
7102                 return err;
7103         }
7104         lock_buffer(bh);
7105         memcpy(bh->b_data+offset, data, len);
7106         flush_dcache_page(bh->b_page);
7107         unlock_buffer(bh);
7108         err = ext4_handle_dirty_metadata(handle, NULL, bh);
7109         brelse(bh);
7110 out:
7111         if (inode->i_size < off + len) {
7112                 i_size_write(inode, off + len);
7113                 EXT4_I(inode)->i_disksize = inode->i_size;
7114                 err2 = ext4_mark_inode_dirty(handle, inode);
7115                 if (unlikely(err2 && !err))
7116                         err = err2;
7117         }
7118         return err ? err : len;
7119 }
7120 #endif
7121
7122 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
7123 static inline void register_as_ext2(void)
7124 {
7125         int err = register_filesystem(&ext2_fs_type);
7126         if (err)
7127                 printk(KERN_WARNING
7128                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7129 }
7130
7131 static inline void unregister_as_ext2(void)
7132 {
7133         unregister_filesystem(&ext2_fs_type);
7134 }
7135
7136 static inline int ext2_feature_set_ok(struct super_block *sb)
7137 {
7138         if (ext4_has_unknown_ext2_incompat_features(sb))
7139                 return 0;
7140         if (sb_rdonly(sb))
7141                 return 1;
7142         if (ext4_has_unknown_ext2_ro_compat_features(sb))
7143                 return 0;
7144         return 1;
7145 }
7146 #else
7147 static inline void register_as_ext2(void) { }
7148 static inline void unregister_as_ext2(void) { }
7149 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7150 #endif
7151
7152 static inline void register_as_ext3(void)
7153 {
7154         int err = register_filesystem(&ext3_fs_type);
7155         if (err)
7156                 printk(KERN_WARNING
7157                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7158 }
7159
7160 static inline void unregister_as_ext3(void)
7161 {
7162         unregister_filesystem(&ext3_fs_type);
7163 }
7164
7165 static inline int ext3_feature_set_ok(struct super_block *sb)
7166 {
7167         if (ext4_has_unknown_ext3_incompat_features(sb))
7168                 return 0;
7169         if (!ext4_has_feature_journal(sb))
7170                 return 0;
7171         if (sb_rdonly(sb))
7172                 return 1;
7173         if (ext4_has_unknown_ext3_ro_compat_features(sb))
7174                 return 0;
7175         return 1;
7176 }
7177
7178 static struct file_system_type ext4_fs_type = {
7179         .owner                  = THIS_MODULE,
7180         .name                   = "ext4",
7181         .init_fs_context        = ext4_init_fs_context,
7182         .parameters             = ext4_param_specs,
7183         .kill_sb                = kill_block_super,
7184         .fs_flags               = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
7185 };
7186 MODULE_ALIAS_FS("ext4");
7187
7188 /* Shared across all ext4 file systems */
7189 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
7190
7191 static int __init ext4_init_fs(void)
7192 {
7193         int i, err;
7194
7195         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7196         ext4_li_info = NULL;
7197
7198         /* Build-time check for flags consistency */
7199         ext4_check_flag_values();
7200
7201         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
7202                 init_waitqueue_head(&ext4__ioend_wq[i]);
7203
7204         err = ext4_init_es();
7205         if (err)
7206                 return err;
7207
7208         err = ext4_init_pending();
7209         if (err)
7210                 goto out7;
7211
7212         err = ext4_init_post_read_processing();
7213         if (err)
7214                 goto out6;
7215
7216         err = ext4_init_pageio();
7217         if (err)
7218                 goto out5;
7219
7220         err = ext4_init_system_zone();
7221         if (err)
7222                 goto out4;
7223
7224         err = ext4_init_sysfs();
7225         if (err)
7226                 goto out3;
7227
7228         err = ext4_init_mballoc();
7229         if (err)
7230                 goto out2;
7231         err = init_inodecache();
7232         if (err)
7233                 goto out1;
7234
7235         err = ext4_fc_init_dentry_cache();
7236         if (err)
7237                 goto out05;
7238
7239         register_as_ext3();
7240         register_as_ext2();
7241         err = register_filesystem(&ext4_fs_type);
7242         if (err)
7243                 goto out;
7244
7245         return 0;
7246 out:
7247         unregister_as_ext2();
7248         unregister_as_ext3();
7249         ext4_fc_destroy_dentry_cache();
7250 out05:
7251         destroy_inodecache();
7252 out1:
7253         ext4_exit_mballoc();
7254 out2:
7255         ext4_exit_sysfs();
7256 out3:
7257         ext4_exit_system_zone();
7258 out4:
7259         ext4_exit_pageio();
7260 out5:
7261         ext4_exit_post_read_processing();
7262 out6:
7263         ext4_exit_pending();
7264 out7:
7265         ext4_exit_es();
7266
7267         return err;
7268 }
7269
7270 static void __exit ext4_exit_fs(void)
7271 {
7272         ext4_destroy_lazyinit_thread();
7273         unregister_as_ext2();
7274         unregister_as_ext3();
7275         unregister_filesystem(&ext4_fs_type);
7276         ext4_fc_destroy_dentry_cache();
7277         destroy_inodecache();
7278         ext4_exit_mballoc();
7279         ext4_exit_sysfs();
7280         ext4_exit_system_zone();
7281         ext4_exit_pageio();
7282         ext4_exit_post_read_processing();
7283         ext4_exit_es();
7284         ext4_exit_pending();
7285 }
7286
7287 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7288 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7289 MODULE_LICENSE("GPL");
7290 MODULE_SOFTDEP("pre: crc32c");
7291 module_init(ext4_init_fs)
7292 module_exit(ext4_exit_fs)